0124080871memory

Human Memory

A CONSTRUCTIVIST VIEW

Human Memory

A CONSTRUCTIVIST VIEW

MARY B. HOWES† and GEOFFREY O’SHEA Department of Psychology, State University of New York, College at Oneonta

†Deceased

Amsterdam • Boston • Heidelberg • London New York • Oxford • Paris • San Diego San Francisco • Singapore • Sydney • Tokyo

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DEDICATIONS To my sister, Bonita Cron.

M.B.H I n loving memory of my uncle, Edward O’Shea, whose sharp recollection of details helped me on many occasions.

G.O’S.

PREFACE This book is intended for the upper-level undergraduate, graduate student, or professional researcher in the field of memory. It summarizes research on a number of fundamental areas of memory and attempts to reexamine these areas through the lens of constructivism, which, simply stated, is the idea that memory content is altered by our cognitions and knowledge of the world.

The constructivist approach to understanding memory phenomena is not new to psychology. Indeed, constructivism is considered to have emerged in psychological research from Sir Frederick Bartlett’s pioneering studies of memory for prose passages in the early 20th century, and later, to have found representation in Piaget’s studies of memory development in children.

In more recent times, constructivism has enjoyed a renaissance across a number of subfields of memory research. Examples of this include Elizabeth Loftus’ research on eyewitness memory, Marigold Linton’s work on the organization of autobiographical memory, and Roger Schank’s theories of the operation of long-term memory. This constructivist renaissance has also spread to a number of other fields dealing with memory phenomena such as criminal justice, history, and education. Thus, because we live in an era where constructivism provides an important foundation to our inquiries into the nature of memory, it is, perhaps, appropriate that constructivism be used as a guiding principle in a memory textbook.

Constructivist interpretation can be applied to two memory processes: encoding and retrieval. When discussing these two dimensions of memory in the classroom, it seems that students have a better grasp of the retrieval process as opposed to encoding. Reflecting this trend, the book moves from discussing retrieval and theories for its operation in the early chapters to discussions of how constructivism affects the encoding processes in the later chapters.

Chapter 1 discusses a fundamental principle of constructivism—that information stored in memory is interassociated or linked—and provides an overview of the various types of links known to operate in memory.

Chapter 2 builds on this idea of memory links and reviews a number of models (including spreading activation), which are based on the principle that memory consists of a web of associated information. ix

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In Chapter 3, another type of link, based on the interassociations of memories along the continuum of time, is reviewed with emphasis on how we organize our memories in a serial order fashion. Specifically, Chapter 3 examines the evolution of serial order models beginning with Ebbinghaus and progressing to the modern oscillator models of Burgess and Hitch (2006) and Brown, Preece, and Hulme (2000). Thus, the early chapters introduce the reader to the fundamental idea that information stored in memory has spatial and temporal properties and that the principles of constructivism operate within this spatial-temporal domain.

Chapter 4 traces the roots of constructivism in memory research, focusing on the aforementioned seminal contributions of Bartlett and Piaget.

Memory is, perhaps, one of the most personal attributes an individual possesses. It orients a person in time by providing a way to view their past, understand their present, and conceive of their future. More importantly, memory makes possible meaningful connections with others by enabling us to make sense of and share our experiences. Chapter 5 explores this more personal side of human memory, and details the role that the mechanisms described in constructivism play in interpreting and organizing our autobiographical memories. The chapter uses some examples of personal memories to illustrate the issues that arise when personal recollection operates on constructivist principles.

Schemas, the building blocks of memory reconstruction, represent how past experiences play a role in creating memories of the present. Although schemas have been implicated in the formation of inaccurate memories, an alternative view is that schemas help to organize and strengthen memory content. Chapter 6 examines this alternative view of schemas, known as the Genevan view or Piaget’s hard-line constructivist approach, and explores the process by which schemas interact with content in long-term memory. Chapter 7 builds on this understanding of schemas and examines the schema-induced changes that can alter episodic memory content, with particular emphasis on the theories of Roger Schank and Elizabeth Loftus.

Retrieval of memory content is, essentially, a decision-making process involving the use of an array of cognitive tools, chiefly among which is inference. A memory system operating on constructivist principles would, presumably, rely on inference during retrieval. In Chapter 8, the role of inference is examined as both a factor in memory alteration and as an evaluative process influencing memory retrievability through such higherorder processes as logical analysis and reality-testing.

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Through Chapter 8, a picture emerges of an active and dynamic memory system reliant on complex, cognitive functions to reconstruct experience. Decision-making processes can be influenced by one’s emotional state. Therefore, constructivist processes in retrieval would also be subject to emotional influence. Chapter 9 explores the role of emotions in such phenomena as flashbulb memories and post-traumatic stress disorder, as well as the relationship between emotions, goals, and self-image in the reconstruction of memories. Chapter 9 also includes discussion on the role played by the amygdala in modulating how we process emotions.

Constructivist thought goes beyond being simply a way to understand how memory functions. Indeed, its principles propose a basis for understanding our capacity for higher-order thinking. Chapter 10 explores the nature of schemas and how schemas become integrated into knowledge structures that function to connect our semantic knowledge of the world to our individual experience. In essence, our experience of the world is mapped onto a rich background tapestry of semantic knowledge that provides us not only with a vast collection of information in memory to draw on, but also with a meaningful view of our experience. We are constantly using schemas as a bridge between semantic and episodic memory. In fact, as also noted in Chapter 10, image and motor schemas provide a bridge to the development of conceptual thought in infants. Thus, a constructivist view of memory is, ultimately, about how memory and thought are deeply intertwined and together, enable us to discover the nature of who we are.

Mary Howes became terminally ill during the writing of this book and unfortunately, was unable to see this book through to publication.

Fortunately, she provided clear instructions for the remaining parts and I was able to complete what she had begun. The ideas in the book are Mary’s and are based on a long career of teaching, research, and thinking about the field of memory research so that this book began, in a sense, many years ago. Her previous academic books, The Psychology of Human Cognition: Mainstream and Genevan Approaches and Human Memory: Structures and Images, laid the groundwork for this current book. Mary and I were colleagues at the State University of New York, College at Oneonta and I worked with her on supplemental materials for Human Memory: Structures and Images, so I was very honored that she entrusted me with the completion of what was her final academic book.

Mary was also a novelist whose book, With the Tide, was, in her own words, “the story of memory, how it hides, or lingers behind doors, only to jump out and startle.” It is my hope that the ideas in our present book may

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yet startle those who read it into thinking more deeply about the elusive nature of memory, how it is at once an integral part of our lives, moving with us, but also moving just beyond.

G.O’S. Oneonta, NY October 2013

ACKNOWLEDGMENT The authors wish to thank Nikki Levy and Barbara Makinster at Elsevier for their helpful suggestions and patience during all aspects of preparing the manuscript.

We would also like to thank Bonita Cron, Shirley O’Shea, and Dr. Michael Siegel who contributed many hours of their time proofreading and whose recommendations proved invaluable to the clarity of the final work.

Additional thanks go to Zoe Hughes and Nick Howes whose expert command of Adobe Illustrator freed up enough time to gracefully finish the manuscript.

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INTRODUCTION One of the most vivid memories of my life involved a time when I traveled with my family to Tangier in Morocco. I was 8 years old.

The first impact came when I saw the Rock of Gibraltar. The colors of that weird shape, the huge lump of mountain, were unlike anything I had seen before. I felt as if some kind of force had picked me up into the air and put me down again. And what followed had the same quality. A ride in a small plane across ink blue water; my father met us at the little airport on the other side. We went out to dinner that evening. The walls of the restaurant were covered in a Technicolor mural of people in (Spanish-looking) fields, carrying sheaves of yellow wheat and fruit and purple grapes, which again impacted me like a hammer. There was deep red wine in glasses on the table. The hotel we went to was called the Isle de France. Our room in the hotel was described as cent-huit in French; so I learned cent-huit, probably with a bit of fast mapping, and knew that it was 108 in English. Also, the sound of huit was like the wheat seen in the restaurant murals.

Our 6-month stay in Tangier brought even more astonishing images and happenings, such that the introduction paled in comparison.

I always knew that I remembered a lot about that time. As an adult I decided to check on the quantity of information. Of course (other than my then 10-year-old sister) I had no way of checking on whether my memory was accurate. But I wrote the material down, and the quantity was indeed very large. Another sign of the power of this particular recollection was the fact that I recalled, after 50 years, the number of the room at our hotel: an achievement I have never duplicated since. And the memories came out in pretty much continuous narrative style: what happened the day we arrived (as described above) and after that while we were at the hotel, and when we moved, and the events that followed later. For a remote memory, this was a lot of information. The perhaps 4 months that we had lived in Dover, in the UK, before the Tangier trip, brings back only a sequence of chimney-pot moments: special events that stand out from a foggy context. Tangier wasn’t like that; it was more of a—long, clear—short story. Across that time I was experiencing something of a state of ongoing happiness and excitement; I loved the place. At eight, I did not see the extreme poverty of the people around me. I saw the donkeys.

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I hope in the present book to make a case for why certain memories like these are very strongly retained, across time, while others are also well retained although they do not involve quite such dramatic events. I also hope to make a case for the critical importance of constructive events: under the view offered here, such events, far from harming our ability to recall through the role of inference, are critical to the remarkable effectiveness and even accuracy of human recall.

I have found, on occasion, that the way memory is understood in mainstream psychology differs slightly from my own understanding. The difference is trivial, but if a wall were measured to run forty feet, under one reading, and forty feet three inches under another, the practical outcome of your choice—between the two measures—could be serious. At any rate, what I hope to do in the present book is to describe the way in which I conceptualize human memory. I am offering a minority position and am aware that many readers will disagree with that position. However, this at least provides a means of raising issues that otherwise might not be considered at all: a way, perhaps, of moving some concerns out of the shadows and into a degree of light.

Sir Francis Galton (1879) famously asked his friends and acquaintances to describe the appearance of their breakfast table earlier in the day. The responses ranged from no imagery at all (i.e. a knowledge of what had been present, but without visual memory “pictures”) to highly vivid imagery.

This appears to be the human range—a large one. I myself generate both memory and mental images, but they are weak: I am a low visualizer. As I walk about in the world, I experience the vivid perceptual input that is common to all humans, but my thoughts and memories are mostly abstract.

Or at least there is a huge quantity of abstract material, accompanied, in the case of memories, by what might be called ghost images.

I was therefore puzzled to read accounts of working memory (consciousness and the domain of material just about to enter awareness) that included structures for maintaining language sounds, and for maintaining sounds in order, and for visual and spatial images—all sensory information—but nothing for abstract meanings. The researchers appeared to take it as given that our awareness did not include abstract thought. Models of this kind have prevailed since the 1960s, and have only recently begun to change. Other areas of research were also puzzling. Cognitive psychologists often cited “context” as a means of accessing a memory, that is, as a means of finding the memory in the long-term store. This did not appear feasible.

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In short, there were a number of theoretical assumptions to which I found myself saying, “But that can’t be right.”

When it comes to philosophical and theoretical models, I am not an empiricist. When I first read the empiricist philosophers, I may have responded as I did (not being converted) because my own cognition leans so heavily toward the abstract. My reaction was that this was beautiful work—very impressive and thought-provoking: and quite wrong. My reaction to Kantian constructivism was different, although I certainly found that work thought-provoking too.

When it comes to psychological models, my orientation is toward hardline constructivism. This includes the approach to memory developed by Jean Piaget. But a strong case—perhaps a very strong case—can be made that the dominant theoretical influence in mainstream cognitive psychology has been empiricist. I believe this is the source of the disconnect—the perhaps three inches of difference in a long wall. At any rate, what I hope to offer in the present book is the other view: a view that understands human memory as being geared to record input from the environment only to a limited degree. Seen in this way, human cognition has other, additional, concerns.

John Locke, generally seen as the father of philosophical empiricism, raised the question (often raised before) of the origins of our ideas. Given that I know what a flower is—how do I know? It seemed clear to Locke that the only source of human knowledge of the outside world must be through our senses—through our eyes and ears and our capacity to touch.

For, what other source could there be? The alternative was, Locke thought, the assumption of ideas simply emerging inside us, as if we could know about the universe without recourse to what we saw or heard or touched.

The notion had the feeling of magic—or, more precisely, in Locke’s day, mysticism: something given perhaps from God (Locke, 1690/1956). As a man who liked the path of reason, and believed that human cognition was a natural process, such a view was not acceptable to the philosopher. It followed, though, from this position, that our ideas must consist of copies of sensory information—images of things seen and heard and touched. It would not be possible to move beyond such images to something else, to abstract meanings, without encountering the same impossible jump: where would the meanings come from?

So, abstract thought, and memories with abstract content, must be rejected. What appeared to be such was really a complex of sensory images.

Further, the organization of the human mind would be largely copied from

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the organization of the environment: the source of knowledge. And just as it appears in perception, the images in the mind were composed from basic, smaller sensory elements: the shape of a leaf, the lines of its veins, the green color. So, ideas and memories were built from units, and the idea as a whole could be understood once the units were understood. The idea was an addition of the units.

Based on an empiricist model, human ideas and thought were also a direct (from the senses) copy of the world outside. Later philosophers in the same line accepted the Aristotelian notion that links (such as identity, similarity, and contiguity links) connect memory representations together.

The emphasis here, though, was on the factor of contiguity: the idea that when two things repeatedly occur together in the world outside, they become linked in memory. So, fork becomes linked with knife, and flower with petal. Here the environment determines the organization of memory content, and contiguity can be expected to play a kind of lion’s role in the work of recollection.

More to the point, though, if human cognition is a copy of the world accessed through eyes and ears, i.e. a fundamental copying function, then processes inside the brain should not come into play to transform the original input. (Some minimal processes were allowed in the case of concepts, such as the additive mixing of original images—a horse and a horn put together to portray a unicorn, for instance: but neither the horse nor the horn, in and of themselves, would alter.) The basic assumption here, when it comes to memory, is one of nontransformation.

Several theoretical positions follow from the nontransformation view.

Most notably, memory content could weaken and fade across time, much like a picture fading from cloth, but, again, the content could not alter.

If you saw a rose, then that particular memory would involve a code for rose, and could never shift to a code for, say, geranium. Memory was like a moving, if dimmed, photograph. David Hume (1739/1965, bk. 1, sect.

1) described this tenet as follows: “Memory preserves the original form in which its objects were presented, and that wherever we depart from it in recollecting anything, it proceeds from some defect or imperfection in that faculty.”

No less important in terms of how memory is perceived, a necessary implication of the present view is that separate environmental experiences will also be held separately in the long-term store. The “true” memory is the input from the world, so it would be harmful to reassociate or reorganize or otherwise shift the original content. For instance, information

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acquired in a particular episode, Episode X, should not become assimilated to information acquired in another episode, Episode Y (see Chapter 7).

Some modern researchers who basically support the empiricist view see the alternative model as rationalism. According to the French philosopher René Descartes, almost all concepts contain abstract components. This is true even of concrete objects that can be easily represented through imagery, such as a table. Descartes’ argument was that even a table cannot be understood without the properties, for instance, of solidity and extension—basically abstract qualities, not given through sensory experience.

The rationalist conclusion, though, concerning this fairly compelling point, was that we are born with concepts already latently present in us.

The concepts need to be activated through experience, but the notion is that we are biologically provided with knowledge of what, say, a rabbit is, requiring only that we encounter a rabbit in the world for the concept to be triggered. Although this view has been defended in the modern age, for instance by Fodor (1975, 1986) and some researchers into artificial intelligence, the difficulties associated with rationalism are quite severe. It can probably be concluded, then, that the real contender against theoretical empiricism involves yet a third view: one that rejects innate ideas (of a rabbit or any other physical “thing”) no less than Locke rejected them. This is Kantian constructivism.

Locke’s model is easy to describe. I think the same can be said for Descartes’ various arguments. But Kant’s (1781/1965) model is not.

Language in his own day may not have served him well, and I am not sure that language is doing any better today. Some aspects of Kant’s thought are expressed in The Critique of Pure Reason; however, Kant can be tentatively described as follows.

We receive sensory experience. Without this, we could never develop ideas or thought or memories. We do not have innate concepts such as a concept of houses or fish or flowers. However, the human mind possesses certain innate capacities. These could be described in modern terms as certain ways of thinking, ways of understanding, or, in the end, ways of interpreting sensory experience. They involve abstract conceptualizations (for lack of a better term). The sensory input to the human mind generally consists of moving and changing lines, contours, colors, sounds, and so on.

The capacity for abstract comprehension enables us to interpret sensory experience of this kind. For instance, when we see one object move and make sharp contact with another object, which then also begins to move, our mind intuits the notion of causality: the first object caused the second

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to move. We never see or hear or touch causality, as such: the mind makes that jump when we see certain kinds of events.

At an even more fundamental level, although what we see directly are shifting line contours and colors, our cognition will interpret certain concatenations of these stimuli as involving individual objects. We construct the idea of objects existing within a space. Again, we directly see lines, but we interpret certain groups of lines as reflecting a “thing,” an object. And when the lines-reflecting-objects change their locations in our visual field in a certain way, we interpret this as movement.

Thus, what we understand about the world is constructed (interpreted) information. The knowledge is not given to us directly through our eyes or ears. Sensory input is, again, essential; it provides the data for the work of construction. But you never see “causality,” or even “number,” as such.

Under this view, concepts of things in the outside world, or concepts of any possible entity, are slowly constructed on the basis of experience. In dealing with spoons or tables the child would see and touch the object, gaining sensory experience, which could be interpreted on the basis of the innate capacity for abstract understanding. It would be discovered that spoons have the capacity to carry food, (capacity for motion and containment) and to be grasped (capacity to be encircled by another thing) and that tables are solid and are used to maintain smaller objects away from the ground, and so on. In this fashion, information concerning the meaning— the nature—of things in the world could be developed.

Under the Kantian model, most concepts in fact involve the synthesis of various different representations into a single functional entity. For instance, we have the concept of a physical body, but that body could be metal or wood or flesh; the single concept “body” allows for many constituents.

“Dog” is the superordinate idea that includes all types of dog. Further, if I encounter a spaniel, the meaning of this entity for me will literally include other representations: dog, animal, living entity, entity. These are not associations with the concept; they are an integral part of the concept, even though each can be distinguished from the other, and employed in quite different contexts from “spaniel.”

Kant’s view was that the objects of perception have been constructed (no less than the objects of thought). The mind was understood as transforming the waves of light or sound received into images: again, acts of unconscious interpretation (processing) were involved. Today, this view appears to be universally accepted when it comes to perception, and models exist that attempt to explain how the visual information is derived

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(Marr, 1982). But the notion of extensive construction in the domain of memory has not been accepted to anything like the same extent.

Shifting now to a modern understanding of the basic ideas of the present model (which is not necessarily a direct copy of Kant’s original views, and takes no account of his particular goals in the Critique), when, again, we see the contours of an object shifting perhaps from left to right across our visual field in a certain way, we do not register just “shifting contours,” but rather what we intuit—conceptualize—is the fact of movement. In this example the thing out there, perhaps a ball, is moving. What we see are changing visual lines; what we understand is the reality of a moving thing.

When one object collides with another, and the second begins to accelerate (in the direction of the applied force), we understand this as causality.

We do not see causality, but the human mind achieves that effective jump.

Locke wrote that understanding could not simply exist somehow in us: we must receive such understanding directly through the senses. He could see no way in which such “given” knowledge could be achieved, short of a literal recourse to the supernatural. But this point, I believe, is less troubling to the modern scientist. The idea that natural functions exist for which we as yet have no model is now generally considered a reasonable idea, and perhaps should be considered particularly so in the case of the human brain with its thousand billion constantly interacting neurons. Certainly, physicists accept this view, in their own field, with no struggle. We do not know as yet how the mind can somehow come to understand properties such as motion, containment, extension, or change—or, say, a condition of not being: but it does.

The tenet that all representation must be of sensory content appears to have been widely abandoned in the cognitive field across the second half of the twentieth century, probably beginning with its abandonment in the area of concepts (Medin & Smith, 1981). It is clear, though, that the influence of the original empiricist model has nonetheless been extensive. For instance, the empiricist tenet that mental functions can best be understood by breaking them down into their units has dominated work in the field of memory since the time of Ebbinghaus. In fact, research involving verbal units [e.g. CVCs (consonant-vowel-consonant pseudowords), words, and numbers] has proved highly successful, not, the case can be made, because the resulting data really do encompass all the phenomena of more complex material, but because such work does tap some of the most critical variables that operate in both simple and complex information. Also, the argument can be made that reducing memory content to its simplest form can, in

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some cases, reveal properties that might be missed (or discovered only after an extended time) in more complicated material. Even so, the overwhelming bulk of research has focused on word item or number item recall, with a relatively trivial quantity of work pursued in the case of memory for material with higher-order meaning, even though such content provides the fabric of our daily lives.

There has also been a long-standing tendency in the field to attribute functions related to memory to a copy of direct, i.e. perceived, environmental qualities, as in the case of the emphasis on environmental context in providing access to learned material. A constructivist in the older tradition would reject the view that context plays more than a trivial role in promoting the recall of, say, a list of words. Something more abstract and more cognitive would be assumed: something like a concept of the list, to which the learned material becomes associated. In short, a kind of continuing environmental bias can be identified in the literature.

Probably the most striking form of this bias, though, involves the following widely held view. It is assumed that events happen in the world, and humans form a copy in memory of these events. Concepts stored in longterm memory (LTM) are indeed activated in the forming of a memory, as may be higher-order interpretation based on background knowledge.

But this copy of an external event is the essential work performed by the memory function: to all intents and purposes, the function ends there. The goal is a copy of experience, of course corresponding to the nature of that experience. If what you saw was a river, then a river will be represented in memory. What is involved at first is the coding of an episode: what happens later is the retrieval of the episode, and the latter embodies the critical work of human memory. This is a copier theory, with allowance for the role of LTM in forming the content of some recollections; but the resulting copy is the point.

The same view would of course be held for non-episodic material, such as memory for the contents of a book or a film, a list of words, and so on.

If the most basic function of human memory is to copy and retain environmental experience, then it would not make sense for the system to permit changes in memory records. The information should be held as it was: an input copy of the world. This would necessarily produce—as it has produced—a strong orientation against the view that memory content, as coded in LTM, can change. And perhaps just as critical, there would also be a bias against the view that the information in a given memory, say for Episode A, could interact with the information in another memory, say

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Episode B. The point of the function is to hold the content of the original episode, and as such interactions between them would violate the most basic principle within the system: that of copying what comes in from the world outside.

In contrast, a view based on a constructivist theory would posit that the basic function of the system is to develop the most powerful or deepcutting information about reality (the world outside) in general. To achieve this outcome, new content needs to be generated—going beyond the immediate conceptual information and images that can be embodied in a memory—and change would be expected. Thus, the hard-line constructivist tradition includes the tenet that content as held in LTM will undergo various transformations: it will change. Also, under the present model, this change is normally adaptive and increases the power of memory, even though on occasion it may lead to error. It is, thus, necessary within this context for information to interact within LTM itself. At any rate, an opposition here between the empiricist and constructivist traditions emerges clearly: under the former, content in LTM itself does not transmute in the sense of leading to further constructed information, while under the latter, it does.

In the present book, I hope to describe some of the work from the mainstream field that I believe is particularly important to achieving an understanding of human memory. I also hope to introduce the major ideas of hard-line constructivism, and connect the two approaches into a kind of “mixed” theory of human recall. I have also used personal recollections throughout to illustrate various points.

M.B.H. Houston, TX August 2012

CHAPTER

1

Links and Cues One summer night in 1999, I heard a thumping noise. I was on the upstairs landing of my house, and the sound came from the front bedroom. It was already dark.

When I entered the bedroom I saw something bang against a window.

It was moving fast, but seemed too large to be an insect. Also there was a clear view, as it swung away, of a long tail. The tail and perhaps the body were apple green, as shown by the artificial light from the house. The weight of the thing—its capacity to thump—was alarming. Heavy like an animal: but green.

In the end I decided that it must have been a moth—a very large one.

But as I first watched this object coming against our screens, I was reminded of a (science fiction) story in which abnormal life forms—mutants—began appearing at house windows: large furred things that wanted to come in.

Later, I learned the name of the creature I had seen. And a while back as I was sitting with a friend drinking coffee, somehow the subject came up. She asked if I had ever seen a luna moth, and as soon as the question was put, the memory of that night came back. And, perhaps a little stranger, a memory of the science fiction story followed on its heels—just as it had when I originally saw the moth.

Next, as I sat with my coffee, a brief recollection came of the second time that I had seen this unusual animal—on the screen of a friend’s house.

But I pushed these memories away; I needed to attend to the conversation of the moment. It was not a time to allow past moth episode after past moth episode to appear in my awareness—as they seemed quite ready to do.

I rejected the extra memories through the process of attention.

MOVEMENT IN MEMORY: THE OPERATION OF LINKS Plato is often quoted as comparing memory to a wax tablet. In fact, the philosopher later rejected this view—with its obvious limitations. He was aware that human recall is not always accurate. Thus, he suggested that recollection might be seen as catching a bird from an aviary, such that sometimes you catch the wrong bird. In other words, you want Memory Human Memory, http://dx.doi.org/10.1016/B978-0-12-408087-4.00001-3

© 2014 Elsevier Inc. All rights reserved.

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A but have retrieved Memory B. Plato thus anticipated the modern idea of source misattribution. And his final attempt at a metaphor (following the birds) was a crude form of the constructivism of the current age, the latter dating back only to the 1900s. But it was not Plato’s insights that informed modern psychology. The major influence came from the equally powerful thought of Aristotle.

Aristotle noted of human memory that it moves. When you recall an event, or other information, the content now recalled changes to other content. There is no kind of freeze-frame, but always a shifting from one recollection or idea to another.

At the level of theory, this movement could be random, or rulegoverned. It is no surprise that Aristotle thought it was rule-governed (Aristotle, 1961). He went on to identify some of the rules, leaving a heritage that in the nineteenth century was adopted by psychologists in their effort to research memory.

One of Aristotle’s discovered rules was that of identity. If you walk into a room and see a parrot, this may remind you of another parrot, encountered on a remote vacation.You then recall the second animal. An identity (parrot → parrot) function has operated.

The idea of this form of movement in human recall has been characterized as involving a link. Identity provides a link between representations in awareness and content in memory. Under the view endorsed in the present book, identity links also move within the memory store itself. In either case, if Constituent A and Constituent B are strongly linked, then the following can be expected. If A is activated, activity will travel along the A-B link in longterm memory (LTM) and result in the increased activation of B. In many cases, if A has first been recalled, this event will lead to the subsequent recall of B. In the example given earlier, being asked about a luna moth led to the activation of the luna-moth concept in my memory (via an identity link), and also to the activation of a memory including a creature of this kind (again, an identity link) and slightly later to the activation of yet another luna-moth memory.

In the original episode, I had thought about a science fiction story while looking at the moth. When some years later I recalled the creature, I next recalled (again) the science fiction story. There are several reasons why this might have happened. One involves what has been widely identified as a temporal link. The events that we experience follow one another in time, and there is a link that catches or exploits this fact. Thus, on the critical night of this event I saw a moth, and just after seeing the moth I recalled

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the science fiction story. The two events followed one another in time, and could therefore have become connected in memory by a temporal link (Brown, Preece, & Hulme, 2000; Linton, 1979, 1986).

Another factor may also have operated. The sight of the moth led originally to the recollection of a story concerning animals coming to windows.

This involved yet a third kind of link, probably centered on a similarity relation. The correspondence here was between a small creature and a larger one, both possessing the qualities of being strange and of coming at night to bang against windows. So the two were similar, and the similarity link could have played through again (autonomously) when I recalled the moth episode in the coffee shop.

Thus, even in this brief example of recall, three major links—moving from one memory to another—can be seen in play.

Links and Retrieval Goals Most research into memory has involved deliberate attempts to recall some target material. The situation described above is different from this. For instance, if you are asked a question, such as “Did you ever encounter X?”, the memory function will in most cases throw up some kind of answer.

This seems to happen automatically, and a great deal of human recall is of this kind. The data suggest that we operate on the basis of background goals, with the goal to answer a question being one of them. In other words, people do not formulate something like, “I now want to remember whether I ever encountered X.” The work of retrieval just occurs.

There are other forms of recall, besides that of the conscious or deliberate work of forming a target, and the relatively automatic retrieval (of which there are also different kinds) described above. However, taking just these two forms of recall for the moment, under what conditions will a memory be successfully retrieved?

First, the memory needs to fit the topic or thought that you want, right then, to pursue. (This includes the fairly broad sense of “want to pursue” described above, such as the probable goal to answer questions.) Second, the content in LTM must be capable of being retrieved.

The episode with the moth met both criteria. I had been asked about this type of creature, so the memory function was oriented toward contacting, and retrieving, the relevant episode. And that episode was strongly coded, since it involved a fairly powerful experience for me. The moment in that bedroom had been strange—odd. And my association with mutated creatures in a story, trying to come in through windows, probably increased

4

Links and Cues

the impact. In the approach to memory of the present book, a strongly coded recollection can usually be recalled.

It is possible that the stimuli that we encounter, and our thoughts, make contact with identical and similar information, of every kind, in LTM, based on the relevant links. Some data support this view (Kintsch, 1974).

However, we do not begin to recollect this great mass of information. It appears that in general certain forms of recall form a target, i.e. the thing “we,” or the system, is oriented at that moment to recall. The target overrides other information—at least in the majority of cases.

It did not surprise me that, when asked, I remembered the night of the luna moth. I was a little surprised, though, to realize that the identical sequence, moth → science fiction story, had played through again in the coffee shop, several years after the original event.

Contiguity, Identity, and Similarity Links Aristotle also identified contiguity, opposition, and (perhaps the most surprising), causality, as cognitive links in human recall. All have been shown to operate as he suggested.The empiricist philosophers who pursued his ideas, however, tended to emphasize some links over others (Hume, 1739/1965; Locke, 1690/1956). Within this context, the contiguity link was notably favored. A contiguity link involves the view that if two things repeatedly occur together in experience, they will become linked in memory. If there is an oak beside a small house that I see every week, the two will become associated together in my mind, such that thinking of one is likely to remind me of the other.

Contiguity here reflects the structure of the environment, and thus fits particularly well with the tenets of empiricist philosophy.

Figure 1.1 illustrates an identity link: moth → moth. A more extended list of variables that can direct the movement of human recall is supplied in Appendix A at the end of the book.

The examples of associative links given above involved object → object links. But if only these operated in human recall, our acts of recollection could be a little restricted. Suppose I am daydreaming, with no particular target memory active. If I then see a filled coffee cup, and if links operated only between objects, I should then begin to recall all the other cups of coffee I have experienced in life. This would surely be a dull exercise, and it is not what happens.

Schank (1982, 1999) noted that identity and similarity links typically operate at a high, generalized level. We move in recollection from one

Human Memory: A Constructivist View

Awareness

5

Memory Content X X

Moth

X Moth

X

X X

Figure 1.1 Identity link. A stimulus, moth, enters awareness and triggers activation of memory content representative of the concept moth. The connection between the stimulus “moth” and the memory representation of moth is known as an identity link.

general theme to another. For instance, reading about a landlord who bought up one property after another, illegally, claiming in each case that this would be the last such predation, might make you think of Adolf Hitler.

Here, there is no identity between individual objects, or even individual actions. There is instead an abstract, high-level identity involving human intent and behavior. Across these two situations, the hostile intent to illegally take control of some entity, for your own advantage, is the same.

Also, the goals involved in memory generally require complex information—an entire event—to be retrieved; so, we do not move from coffee cup to coffee cup.

Links and Memory Strength Until now, links have been described only as involving movement. But they provide yet another property. Under the model endorsed in the present book, they provide a strength factor.

If A and C are linked, and A is activated, the activation moving to C will increase C’s ability to be recalled. C becomes stronger in LTM. This effect has been described here in a certain way: as activity moving along a link. It can be conceptualized, however, somewhat differently—in a manner that turns the notion of “link” into something a little more difficult to imagine.

The issue is examined in Chapter 3.

An example of the capacity of links to increase the strength (capacity to be recalled) of the “receiver” constituents in LTM can be described as follows. Suppose you are asked what you did on Monday afternoon.You do not remember. One strategy would be to try to recall what you did at lunch on Monday, and see if you can move from there to what happened directly

6

Links and Cues

after lunch. You may then remember the early events of the afternoon, although you had been unable to recall them before. We use this approach spontaneously. And it is often successful. If you could recall the lunch, the events following it would be associated with the lunch via (possibly) a temporal link. Moving from recollections of lunch to the time following lunch may strengthen the latter memory.

We also possess, and can use, backward temporal links. I can, for instance, reconstruct the events of this early morning by moving from the present moment to the slightly earlier time when I searched for a missing piece of paper, and back from there to the yet earlier time when I went downstairs to make tea.

CUES It was once widely believed that human memories are of two basic kinds.

The dominant layman’s belief appears to have been that there are the memories you can recall and the memories you cannot recall. In other words, some are strong and some are weak. Thus, successful recollection would depend—entirely—on the internal condition of the relevant memory codes.

On occasion, a memory might be difficult, so that you had to work to get it back. But this could still be understood as falling into the first, juststrong-enough-for-recall, class, although perhaps blocked for a while.

A view that was widely endorsed by psychologists explained strong and weak memories in a different way. Under this assumption, a memory once entered into LTM was present in the long-term store in an absolute fashion. It was “there,” much as a physical object might be present in a cupboard. The problem lay in accessing the memory. Some were easier to find—or access—than others.

Research dating from the late 1960s established that the first way of thinking (i.e. that a memory can be retrieved or not retrieved depending only on its internal state, seen as its strength) is fundamentally wrong. The new insight was established primarily by the psychologist Endel Tulving, in the course of his work centered on the human recollection of random word lists (Tulving, 1974, 1976, 1983; Tulving & Osler, 1968).

Tulving’s insight reflected the relations described in the previous section: the relations that hold between conscious awareness (identified in psychology as working memory) and content in LTM (defined as the capacity to retain information for longer than about 45 seconds). He had found

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that when words on a list were learned, they did not appear to have an autonomous inner state that solely determined whether they could, or could not, be recalled (Flexser & Tulving, 1978; Tulving, 1976; Tulving & Psotka, 1971). In short, the description of memory offered above (strong/ recallable or weak/nonrecallable) did not seem to fit.

Suppose certain items (among others) on the list are ELEPHANT, GOOSE, COTTON, MACAROON, HOUSE, OTTER, BOY, ZOO, HAND, and that the experimenter announces when the list is presented that many of the items are characterized by a repeated letter.

A subject later reports all that she can remember of the list. She fails to recall GOOSE. Following her best attempt at recall, the experimenter reminds her that some of the items had a repeat letter embedded in them.

She then recalls GOOSE. Thinking of the repeat letter at the time of recall (“repeat letter” being a prompt) changed the status of the memory item, shifting it from something that couldn’t be recalled to something that could be recalled.This clearly weighs against the belief that an item will either be remembered, or not, depending only on its intrinsic background strength (i.e. how strongly it has been coded into LTM due to rehearsal, etc.). Tulving’s research uncovered the following patterns. If the subject had noticed the double letters during learning, and recalls this property during the test, then recall will again be facilitated. In contrast, a property that is not noticed during learning will typically not function as a helpful cue at the time of the memory test.

The point for the moment, however, is this. The way an individual is thinking at the time of recall can change the status of memory content in LTM, altering it, in some cases, from a condition in which it cannot be retrieved, to a condition in which it can. If you don’t remember the fact of “repeated letters” when tested, you may not remember GOOSE. Since the way an individual is thinking at the time of attempted recall may determine her success or failure, the goal to remember items on List X does not depend (for a good outcome) solely on some internal property of the List X items.

The contents present in working memory when an attempt is made to recall some target are labeled cues. A cue is anything thought or perceived (or event felt) at the time of the attempt. Cues make contact with material in LTM on an identity basis. (Under certain models, there may be other associative links that also perform this function.) Thus, if you are thinking tree, tree representations will be contacted in long-term store. If you are trying to recall a weak memory, but the representation tree is present in

8

Links and Cues

that memory, someone prompting you with this word could result in your being able to recall the target (even though you could not before). The TREE cue, once provided, will contact and so increase the activation of the tree element in the memory. This increase could lead to the entire target recollection, in which tree is embedded, being recalled.

To summarize, there is a relation between (1) current thoughts and perceptions and (2) memory content. What you are thinking or seeing or hearing at the time of recall can change the internal condition (the activation level) of a memory.

Tulving’s Cue-Dependent Theory of Forgetting Given the discovery of the power of immediate thought and perception to change the status of LTM content (from something that can’t be recalled to something that can, or vice versa), it would be an obvious step to go to the extreme alternative, and conclude that there is no differential strength of material coded into the long-term store. In other words, all content entered into LTM operates at the same level of strength.

This leads to the original cue-dependent theory of recall and forgetting, advanced by Tulving (1976) following his extended research into the role of cues. According to cue-dependent theory, as first posited (but later rejected)

by Tulving, memory content has no internal property that can influence recall. No memory is either stronger or weaker than any other. Instead, success will occur when the operating cues overlap significantly with the target content in LTM. Such overlap activates the content to the point where the entire memory set can be recalled. In contrast, if the operating cues do not overlap with the target, or do not provide sufficient overlap, then the attempt at recall will fail.

A critical point, however, is that the match between cue and memory content depends on how the individual conceptualizes each of these constituents, rather than their external form (Flexser & Tulving, 1978; Tulving & Osler, 1968). Suppose the cue dog is given at learning for the target word OBEDIENT. If at the time of test the subject has just read The Hound of the Baskervilles, and is thinking of dangerous dogs, then the cue may not help.

The cue-dependent theory of forgetting, as described above, was once widely adopted among psychologists; it seems to have found its way into every text on memory. And laymen have also become familiar with it.

Following a graduation ceremony many years ago, I was standing in a small group that included the then-president of the college (he has retired

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now, and so has the president who followed him). He put his hand on my shoulder and gave a brief, competent explanation of the idea that we forget information when we lack the “right” cues. This view was presented as an established fact. I don’t think he knew that my field was memory.

In fact—an important issue—Tulving revised the original theory after encountering data, based on his own work, that failed to support it (Tulving, 1983, chap. 14). He found, among other things, that the same cue and the same target can produce different mnemonic outcomes, depending on the task. Yet cue/target overlap, given the experimental conditions, would have been the same in both.

In modifying the original theory, Tulving abandoned the view that all memory content is the same in terms of the possibility of its retrieval. He suggested that some information stored in LTM has more “quality,” than other information. In the case of high-quality information, only a small or even minimal amount of cue-content overlap is needed for retrieval.

Here, the idea of quality appears to correspond to the concept of memory strength as used in the present book.

It should be noted that the original cue-dependent theory of memory (the hypothesis that success in recall depends entirely on adequate cues) has been rejected by its originator, and there is clear evidence that it is not valid.

Even so, the fact remains that a weak memory can be strengthened by cues.

This is the case, even though the data demonstrate that some memories are strongly coded (or high in quality) and some are weakly coded, and there is an entire range in between.

Nonetheless, with weak memories, cues can make all the difference.

MODELS OF MEMORY RETRIEVAL It is clear that associative links operate between awareness and the memory store. If I see a parrot (a conscious experience), I may then recall another parrot whose representation was coded in LTM. Current models of memory can be divided into two major types. The first holds that links operate only between working memory (awareness and the fringes of awareness) and the long-term store. I shall call these cyclical retrieval models. Under the cyclical retrieval view, links do not operate to associate material within LTM itself.

The second theoretical approach, identified as spreading activation models, posits both links operating between working memory and LTM and links operating within LTM itself, at a nonconscious level.

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Links and Cues

Cyclical Retrieval Models Some approaches within this tradition posit many forms of link operating between awareness and LTM (Gillund & Shiffrin, 1984; McKoon & Ratcliff, 1992; Ratcliff & McKoon, 1994), while others posit the operation only of an identity link (Tulving, 1976, 1983; Tulving & Thomson, 1973).

The term working memory is generally used in the psychological literature to denote awareness and also the immediate wings of awareness (i.e. something that is about to enter this state, but has not yet done so). Thus, cues are understood as operating in working memory.

In cyclical models, it is assumed that a given memory consists of a set of information. For instance, a word in a list of words would constitute a single set. There could be many constituents within that set, comprising the phonemic or semantic features of the word. If the operating cues are associated with the features in the set at a level sufficient to bring a certain critical degree of activation to the set as a whole, then it will be retrieved; that is, the word will be retrieved.

Once a set has been recalled, the features in that set then operate as cues in working memory, and may be capable of contacting other sets in LTM, and so of retrieving them. The same occurs when the next and the next set is retrieved, providing the cyclical aspect of the model. Also, all the retrieved information, and so all the cues, can operate together, a phenomenon that has provided the label compound cue models for approaches of this kind.

Figure 1.2 shows a model of how the association value between multiple cues in short term memory (STM) can determine the success of retrieving related information from LTM. An example from natural memory might be the following. Suppose I am asked who sat next to me at a dinner attended last April. The memory is weak and I fail to recall the answer. This means that the cues, probably “dinner, dinner at Anna’s house, in April, who sat next to me?� have not provided sufficient overlap with the set containing the target memory to activate and retrieve that memory.

I am then reminded that a Frenchwoman had attended the dinner. This additional cue provides activation to a memory set that corresponds to the earlier cues, and also contains information concerning some of the conversation held at the dinner table. Now all of this information is retrieved.

This set of compound cues may be sufficient to contact another relevant memory set (due to the cues overlapping with that set) that contains

Human Memory: A Constructivist View

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RETRIEVAL STRUCTURE DOCTOR-DOCTOR

1.0

NURSE-NURSE

1.0

BREAD-BREAD

1.0

NURSE-DOCTOR

0.5

NURSE-BREAD

0.1

BREAD-DOCTOR

0.1 Doctor

Nurse

Hospital Bread Doctor

Bread Butter

Food Jam

Doctor

Nurse

Hospital Nurse Doctor

Bread Butter

Food Jam STM

LTM

Figure 1.2 Compound cue activation model. Stimuli enter short-term memory (STM). Each item in STM has an association value with items in long-term memory (LTM).

An item in STM has a strong association value with the representation of the same item in LTM (that is, with itself). Semantically related items have an association that is weaker than that of an identity relation, but stronger than that of unrelated items. If NURSE and DOCTOR are presented in sequence, DOCTOR will be strongly associated with itself in LTM, and NURSE will have a medium association with DOCTOR in LTM. As a result, the match with DOCTOR in LTM is made more quickly than usual (a priming effect).

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Links and Cues

information about not only the Frenchwoman and the conversation but also the person who sat next to me at the dinner. The target memory is then retrieved.

This provides a greatly simplified description of the model, intended to convey the general principles involved in the idea of cyclical retrieval.

Critically, all recall depends on cues contacting information in LTM, and that information being returned to working memory, and so possibly contacting LTM again.

A major historical root of cyclical retrieval models can be traced to a computer simulation developed by Gillund and Shiffrin in 1984, which successfully modeled recall and recognition of word lists.These authors in fact posited a small associative activity within LTM, but the essence of the model was again movement between working memory and LTM. A range of other cyclical retrieval models, and related theory, has also been developed (Anderson et al., 2004; Anderson, Bothell, Lebiere, & Matessa, 1998; McKoon & Ratcliff, 1992; Ratcliff & McKoon, 1994; Tulving, 1976, 1983; Tulving & Thomson, 1973).

Cyclical retrieval models may encounter some difficulty, however, in the case of episodic and autobiographical memories. Given that we live each day in a continuous stream of time from perhaps early morning until night, the question emerges as to what function could cut or divide this stream into individual sets, with boundaries. What would the criteria be for establishing a set, especially as it seems that each would have to be quite small? For instance, if “what happened at dinner in April� were a single set, it would be so large that basic specification cues could not overlap with the set sufficiently to activate the set, and so retrieve any information at all.

To some extent all models have the same problem. This is caused by our remarkable capacity to recall episodes on a selective basis. I can retrieve information concerning only breakfast on a certain day, only the content of a talk, or only what happened when a vase tipped over, or I can retrieve information concerning the day as a whole. A spreading activation, associative model can explain this, however, without any assumption of bounded sets, although the explanation does imply a formidable associative capability.

The relevant function is described later in the book. (It is not addressed in the description of spreading activation models below, which is intended only to cover some basic principles.)

Spreading Activation Models Spreading activation models posit the operation of links within LTM as well as between working memory and LTM. In other words, if a representation

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involving a particular person is activated in the long-term store, the activity will spread to other representations concerning that person, and perhaps also to a similar individual, within LTM itself; that is, at a nonconscious level. This material may or may not be retrieved into awareness.

Here, the long-term store can be conceptualized as a vast network of representations, connected by links.These representations are understood as possessing a degree of background activity (strength) that differs from one to the next. Thus, in my case the representation of my dog will have a high level of this background activity, which simply means that my knowledge concerning him is strongly coded. In contrast, my representation of a dental receptionist who I had never met before but with whom I spoke last week will have a low level of activity. I don’t remember her very well.

When cues contact such constituents in LTM, they increase the activity level of these constituents, such that increased activity spreads from the representation that has been contacted, say Representation X, out into the net, via the links leading from X. This spread will increase the background activity level of the representations that receive the activity.

Cues have a particularly strong influence here. An element that is activated above baseline in LTM (perhaps by input from another element, although not by cues) will show an increase in activity. But this increase will be less than would have been provided had this information been contacted by a cue or cues.

Representations (or any body of information) that reach a high level of activity, crossing a certain threshold, will be potentially capable of being recalled. Representations that fail to achieve that threshold will not be capable of being recalled. Roughly, memory content that is coded at sufficient strength, at any given moment in time, under conditions in which the individual wishes to recall it, may be retrieved into awareness.

Activation triggered by cues spreads through the net for a limited period, and then dies out. If this did not occur, the net would be in a constant state of extended activation, and retrieval would become incoherent.

The degree of activation spread through the net, and the speed with which material may be retrieved as a result, is wholly a function of the strength of the links (and those properties, not yet discussed, that provide strength). No constituents are “closer together” or “further apart” in LTM as such. Movement, again, depends entirely on the links and their strength; not on any spatial property within the long-term store.

The concept of a spreading activation was first developed, in the form generally endorsed today, by John Anderson and Gordon Bower (Anderson,

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Links and Cues

1976, 1983a; Anderson & Bower, 1973), and this general model, described above in a highly simplified fashion, has been developed in a variety of forms by a range of researchers (Botvinick & Plaut, 2006; Brown et al., 2000; Burgess & Hitch, 2006; Collins & Loftus, 1975; Kintsch, 1992; McClelland, 2000; McClelland & Rumelhart, 1986; McNamara, 1992; Rumelhart & McClelland, 1986).

A schematic representation of the basic spreading activation model is shown in Fig. 1.3.

Central Node STM LTM Element 1

Element 3

Element 2

Node b1

Node a2

Node a1

Element 6

Element 4

Element 5

Node a3

Node a4

Node a5

Element 8

Element 9

Element 10

Node b3

Node a6

Element 7

Node b2

Figure 1.3 Spreading activation in LTM. When a stimulus in short-term memory (STM) contacts memory content in long-term memory (LTM), activation spreads from a central node along links to associated elements (e.g. Element 1, Element 2, . . .). These elements are linked to associated relevant terminal nodes (Node a1, Node a2, . . .) and irrelevant terminal nodes (Node b1, Node b2, . . .). Movement through the network is determined by the association value of the links between the elements and the nodes.

The relevance of the nodes is determined by the association value of the link between the central node and the terminal nodes. The speed of retrieval from LTM is a function of the strength of the links.

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Interference Effects If all that was involved in spreading activation was a process in which cues strengthened the activation of certain materials in LTM until their retrieval could occur, then understanding success and failure in recall—in a sense, understanding memory—would be an easy task. But this is not the case. Other variables operate. In fact, this almost always obtains when any function related to recall is examined; one type of activity cannot usually explain the outcome.

The level of background activity of representations in LTM was mentioned above. This determines the potential capacity of that information to be recalled (all other factors being equal).What provides this kind of strength in the case of memories with higher-level content is a major theme of the present book, although definite answers here have not been established.

In contrast, in the case of random word items, following 100 years of research the answer to the question has been established. The major factors are background familiarity, imagery content, concreteness, and the degree of associations of one word target with other words within the list (Deese, 1966; Kintsch, 1970; Kucera & Francis, 1967; Noble, 1952; Paivio, 1969, 1991;Thorndike & Lorge, 1944) and of course rehearsal.Thus, if a word on a target list is often rehearsed it will be markedly better recalled; as noted above, other factors that increase its probability of recall include a large number of associations with other words (e.g. “house” as against “gurney”), how often it has been activated in the past, its concreteness (“brick” vs. “extension”), and the degree to which the entity named by the word can be imaged.

In the case of memory content of any kind, it can sometimes be recalled, and sometimes not. The material above focused on the properties that increase the potential for recall. The other factor that plays a huge role here involves the phenomenon known as interference.We forget material due to interference effects, and these operate in a markedly different fashion from the processes involved in spreading activation. And in a spreading activation model, of course, both factors are in play and can work in opposition to one another.

Interference effects can be assumed to be present in any body of memory content that is weakly coded—for whatever reason (lack of attention, triviality, an overload of content, the passage of time, and so on).

Interference has been extensively researched since the 1930s and a great deal is known about its properties. In contrast, a theoretical understanding of the phenomenon remains controversial, with two opposing positions largely dominating the controversy. Appendix B provides an overview of

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Links and Cues

what we know about the phenomenon and some introduction to theory in this area. At the very least, the phenomenon itself is of great interest—and perhaps strangeness.

Applications of Retrieval Models to Everyday Uses of Memory The following example shows how the dinner party memory, described above within the context of a cyclical retrieval model, would be conceptualized under a spreading activation model. This example does not include interference effects; exactly how such effects operate has been explored relatively little within the context of material with higher-order structure, while its operation in the case of random words or random facts has been deeply researched, again, for almost 100 years. But given the relative paucity of our knowledge concerning how interference might operate in a memory of a dinner party, the following example focuses only on the effects of spreading activation as such.

I am asked about a certain April evening. The question involves a dinner. I try to remember, but little comes back. Someone prompts me with, “Remember, there was a Frenchwoman present.” I then begin to recall the dinner—who was there, what was said, and so on.

The dinner memory here can be seen as a vast network of associated representations. Most of the links are weak and just thinking about “that dinner in April” fails to retrieve the full memory. But when I am reminded of the Frenchwoman, this cue contacts and increases the activation of the Frenchwoman content within the network. This material is strongly associated with the content of conversations held at the table. The activation spreads to those conversations, and then out further into the net, until a great deal of relevant information can be retrieved.

Under some models, once increased activity has begun within the net, the activation may loop back from one set of content to another, resulting in an increasing effect (Kintsch, 1974).

Critically, constituents that are highly activated are “stronger,” that is, they are more likely to reach the threshold required for retrieval into awareness. As in cyclical retrieval models, this retrieved information can reenter the net, providing the usual marked additional activity, typical of cues, to whatever content they access.

Within the network, some links that relate one constituent to another are relatively weak and some are relatively strong.Weak links are unlikely to provide sufficient activation to their recipients to provide recall. However, a given constituent can be related to many others, and receive simultaneous “weak”

Human Memory: A Constructivist View

17

input from more than one source. This input will summate (or increase the relevant effect in some way, which could be additive or multiplicative).

An extremely critical aspect of the issue of link strength involves a property identified by John Anderson on the basis of research into the formation of new links (Anderson, 1981). Ebbinghaus had posited that representations in memory do not change in strength, in and of themselves, and are therefore not relevant, as such, to the issue of success in retrieval.

The critical factor must be the strength of the link leading from A to B. Anderson reported data indicating that this “link strength only� hypothesis is not correct. A strongly established memory constituent (such as knowledge of a famous person, as against a newly introduced and unfamiliar person) will result in any links created from the former to other material to have greater strength, from the beginning, than links created from the latter (unfamiliar person). In other words, it is easier to learn new information related to a solid body of known content than to unfamiliar content.

A final point concerning cues is the following. In general, cues determine the content that will be retrieved in any given act of deliberate recall.

The exception involves highly emotional or traumatic content, which may appear spontaneously in awareness, overriding the operating cues. For instance, individuals who saw a frightening accident at the Hyatt Regency Hotel in Kansas City could not later stop remembering the scene, which would force its way into awareness (Wilkinson, 1983).

Retrieving a Long-Term Episodic Memory In 1995 I went on a trip to New Zealand. At the end of some days on that trip, I recorded the relevant events in a journal. Then, in 2008, I tested my memory of that holiday.

Even in very strong episodic recollections, there are always gaps. To be more precise, if the memory is more than 24 hours old, there will be gaps.

Since this one was recalled after 13 years, many of the unimportant details (and, as it turned out, some important ones) had been forgotten. The material below involves a single day, characterized by very poor recollection. It centers on the time we visited a South Island town called Dunedin.

The Memory, as Written in 2008 I recall the spatial layout of our motel room. There was a large French window opposite the door, with the beds on the left-hand side as you entered.

(Confidence level on a 0-5 scale: 3.5.) I recall that I liked the big window and the generally modern, light-filled appearance of the room (3.5). Also, I

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Links and Cues

was thinking that I wanted the same kind of effect in a house of my own one day (5.0).

I am having trouble with what we did that day. We went on some tourist trips. I recall a tour bus and seeing houses built on the side of precipitous green hills (2.0). The bus driver told us about the houses, but I don’t recall that information (1.5). Did he say that Janet Frame had lived in that area? (0). The town was largely closed, but I think we walked there. There was a long main street with—a statue of some kind (1.0) Historical statue? (0). I think we saw some public gardens and maybe a fern-house—but there was not much growing (2.0). It was a bit drab (4.0). Also, the gardens may have been another day. I think I recall a street in the town and some houses on the far side; there was something about the houses—but I can’t recall what (1). We saw this toward evening (1).

It was on the cold side (3). I think I have drawn on things we did across the weekend there.

I can’t get anything else back.We ate in the restaurant at the motel (4). It was quite crowded and there was something noticeable about a waiter, but I can’t recall what (1.5). I am not sure that the waiter or crowd belonged to that particular day. I think we ate fish or other seafood (1.0). That’s it.

A Stronger Cue A few days after my attempt at the Dunedin recall, I was walking along Main St. in the town where I live. There was a sport shop and in the window I saw a piece of polished wood. It was carved in the shape of a seagull’s wing. I have included the weak recollection of the Dunedin weekend because of what happened next.

When I noticed the seagull-wing shape of the wood, I thought: it’s like the wing of an albatross (similarity link). And then the missing content from the Dunedin memory, concerning some “tourist trips” came back—at once.

Albatross! We had gone out on a boat to see albatross nesting.

What followed, a thing that is highly typical of episodic memory, was this: once I recalled the albatross-boat-ride cue, a wealth of further detail came back. I recalled the beach where we had waited for our ride. I recalled little rivulets of water running down the beach. I recalled that it had been cold, going up a kind of ladder into the boat, that we had drunk coffee, a little about the appearance of other people on the boat—and much more.

I also recalled that the albatross, nesting on a cliff, were shown to us, but I couldn’t really see them. They were too far away.

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A point of interest here was the cue: the piece of polished wood. At first what happened may appear fairly obvious. It was an albatross → albatross link, certainly. But in what way? It was not, for instance, a link based on direct perception. The shape of the polished wood did not match with my episodic memory. This is because the birds at Dunedin had been too distant for me to actually see their wings.

What I found in the sports shop window was a shape that I knew to correspond to the outline of an albatross wing. So the wood shape had made contact with a generalized albatross-wing shape stored in my memory (perceptual information), which presumably led to the abstract concept (the idea: albatross), which made brisk contact with the content, also stored in LTM, that we had gone on a boat ride to see albatross on the cliffs. The final step, then, was an abstract, conceptual (identity) albatross → albatross link. (In fact, all I had seen on the cliff were some pale blobs.)

When I had made the original attempt (after 13 years) to recall the target Dunedin day, I had recalled that we went on some tourist trips. But when I asked, “What trips were they?”, this cue failed to activate the boat episode. Yet the fact that the episode involved a tourist trip was certainly embedded in the memory. Apparently the links in LTM between the two (Dunedin tourist trip → boat at Dunedin etc.) were not strong enough.

Yet when I simply thought “albatross,” the recollection came back immediately. What then constituted the difference, with regard to the cues?

CHAPTER

2

Spreading Activation Under the traditional empiricist model, the structure of our thoughts and memories matches the structure of the environment. It follows from this belief that contiguity links should play a major role in human recollection.

If I repeatedly see some blue morning glory on a particular porch, then thinking of the porch (or seeing it again) is likely to remind me of the flower.

In the same way, it could be assumed that a memory would normally be associated with the outside context in which the memory was formed.

These being widely held assumptions of cognitive psychologists throughout the 1900s, the issue of context—and the role of contiguity links—was researched in some depth. It was expected that these factors would play an important role, even the major role, in recollection.

If I am sitting in a room with blue walls and long windows, and memorizing a list of words, then the walls and windows and other stimuli around me (the context in which this new memory will be formed) should become associated in long-term memory (LTM) with the words being learned. This involves a straightforward contiguity link: the various environmental stimuli occur in my experience at the same time as the words. It follows that if I am tested in the same room, and see the blue walls and long windows again, these cues will contact their representations in LTM. These representations are now linked in the long-term store with the words that I learned earlier, and so should lead to the activation of the words and the retrieval of the memory. In this fashion, “context” can be seen as providing recall. Figure 2.1 shows this sequence of events.

It is posited in the present model that each word would become individually linked to the environmental stimuli. Depending on factors such as attention, some items would enjoy stronger links to the context than others. It is also posited that the series of words become associated with one another, possibly on the basis of a contiguity link (one word would appear next to another, and so on) or on the basis of a temporal link. Thus, environmental context would be expected to play a major, but not the only, role in the process of recollection. The present description conforms to an associative, spreading activation model.

Human Memory, http://dx.doi.org/10.1016/B978-0-12-408087-4.00002-5

© 2014 Elsevier Inc. All rights reserved.

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LIST X ROBIN LIGHT BLUEBIRD TABLE ROSE

WORDS LEARNED ON MONDAY

Figure 2.1 Contiguity links for word retrieval. Illustration of the links established between a learning situation and the environmental context in which the learning occurs. While learning a list of items, the figure at the desk also learns the layout of the environment in which this learning takes place and associates in memory certain features of the environment such as the window and the door with items on the list. The box at the lower right of the figure indicates the associations that form between words on the list and features of the environment in which the learning occurred.

Cyclical retrieval posits the same outcome, in a slightly different way.

Here, the word items and the stimuli reflecting the room would be entered into the same memory set (having occurred together, and with the room stimuli being attended to some degree). As a result, the window stimulus or the wall color stimulus, etc., if present at recall, would make contact with the target memory set and so increase the level of overlap between cues and target, and again aid in recall.

MEMORY AND CONTEXT In further support of this view of the importance of contextual elements, such associations have been shown to operate in human infants. Infants who learned to kick when seeing a certain mobile—since the kicking

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action caused the mobile to turn—were significantly more likely to recognize the mobile, and so to kick, if the object was presented in the room in which learning had occurred (Rovee-Collier, 1999; Rovee-Collier, Hartshorn, & DiRubbo, 1999). Perhaps the walls had, again, been blue.

If so, the color became associated with the learned kicking response. (It should be noted, though, that this response could involve conditioning, rather than true episodic recognition: even so, the influence of context is clear.)

Concerning adult recall, S. M. Smith examined what happens when a list of words is learned in a certain room and later tested in the same room, as compared to the test occurring in a different location (Smith, 1979).

Recall was slightly stronger in the same-room condition, and the difference was significant. There was even a small, but also significant, improvement when participants were tested in a different room but were instructed to imagine the context that had been present at the time of learning (Godden & Baddeley, 1975; Smith, Glenberg, & Bjork, 1978).

Subsequent studies examined a range of situations in which the (internal or external) environment at the time of learning either matched or did not match the environment at the time of the test. These included the physical context and the mood or physiological state. With regard to the last variable, the assumption would be that if you experienced, for instance, stomach ache during learning, the feeling of stomach ache should help you to recall the material at the time of the test.

The overall results were mixed. In the case of mood, some studies found slightly improved recall when the mood states were the same at learning and at testing (Bower, 1981), while others reported no effect; the same mixed pattern emerged for physiological state matching (Bower & Mayer, 1985; Gage & Safer, 1985; Wetzler, 1985). Other studies failed to find improved recall in the case of matched physical contexts, thus failing to replicate Smith’s original data (Saufley, Otaka, & Bavaresco, 1985; Smith,Vela, & Williamson, 1988). Also, researchers established that an effect for mood matching may be found when two lists are learned in succession, but not when a single list is learned (Blaney, 1986; Ellis & Ashbrook, 1991). And, of particular importance, effects of matching did not emerge in the case of content with higher-order meaning, as against random word learning.

In all, what conclusions can be drawn from these data? The basic issues here involve how LTM is accessed following learning (does the context in which learning occurs play a major role in contacting information in

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the long-term store?), and what provides successful recall. We humans are efficient at entering information into memory, and to some considerable degree are also efficient at recalling that information. But, clearly, general context is not the factor that provides this ability. A reasonable conclusion would be that contiguity effects (between the external or internal conditions at the time of learning, and the learned material) play a role in determining retrieval; but a very weak role. Under many conditions, the effects cannot be seen at all, while under others, the effects do appear, but more reliably with random item material than with “natural” content possessed of higher-order meaning. The causal factors that primarily enable our memory function must be sought elsewhere.

Even so, some matching states, such as physiological matching effects, are not without interest. It was found that when individuals were drunk at the time of learning, they recalled the target material better when they were drunk again, as against sober, thus providing evidence for anecdotal tales concerning how to find the keys you lost after several beers. The good news, though, was that people who were sober both at learning and test did better than those who were drunk on both occasions (Goodwin, Powell, Bremer, Hoine, & Stern, 1969).

As noted earlier, these data provided by adults contrast with findings in the case of babies and animals. Rats are notoriously context dependent in recognizing stimuli, and it appears that human infants show a similar pattern (Boller, Grabelle, & Rovee-Collier, 1995; Richardson, Riccio, & Axiotis, 1986). Apparently—hardly a surprising outcome—new functions come into play as the cognitive system matures. Contiguity links are real enough, but other factors play the stronger role.

A model concerning the fashion in which memories are in fact accessed at the time of retrieval (given that context does not provide the basis of this function) is described below.

Anderson and Bower’s FRAN Model of Spreading Activation In 1973 Anderson and Bower published their model of spreading activation, in the form of a computer program called FRAN (Free Recall from an Associative Network). FRAN was the seminal approach to spreading activation, with the ideas developed in this work influencing the field from the 1970s to the present day. She could learn (encode) the word items on a list, and later recall or recognize them, providing generally accurate output, and indeed output similar to human recall. (Given the name, I always see FRAN as female—clearly an example of gender bias.)

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Something must begin—launch—a deliberate memory search. Probably again due to historical influences, Anderson and Bower conceived this factor to be context: the context in which a target list of items had been learned. This included everything that might be present and experienced at the time of learning: the physical appearance of the words, perhaps in large letters and dark ink; the stimuli present in the room, such as white walls and a blackboard, or the smell of flowers through an open window; and thoughts present at the time. Assuming that the word list had been memorized earlier, this complex would launch the relevant memory search.

It might at first seem that the idea outlined above must be quite untenable, given that it seems to imply that a memory could only be retrieved— the search would only be launched—if the context of learning were reinstated, i.e. if you were in the same place where you had memorized the target words. But, as I understand the early emphasis on context, what was assumed to operate was a mental rather than a physical reinstatement. You could be in any environment, and perhaps an experimenter might say, “I want you now to recall that list you learned earlier.” Under this model, the concept of “that list” is the set of environmental stimuli that had prevailed during learning. Therefore, when you are asked for recall, you activate the idea of the list, which is in fact a complex of images of the words and the room and so on, and the target items are associated in LTM with that complex (due to the associative, contiguity-based events that occurred at learning). This environmental complex then contacts the target memory.

Attempts to embody a concept, such as “that list I learned,” in the form of sensory images were abandoned in the years that followed FRAN. That our ideas must be constituted of imagery was of course the basic LockeanHumean position. But a simple alternative exists: it involves the generation of an abstract cognitive representation, carrying the same information as the words, “that list I learned.” This, rather than environmental context, could be the cue that launches the work of contacting a memory.

Theoretically, of course, moving to the assumption of such a nonsensory, abstract cognitive element is a giant step. But it appears to have been taken without much concern for the implications: a shift from traditional empiricism into either rationalist or constructivist theory (because an abstract representation of this kind is not accepted within the traditional empiricist tradition). Regardless of this background issue, Anderson and his colleagues today support the view that abstract representation does exist in human cognition, and have even developed a widely endorsed model of such representation (Anderson et al., 2004).

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Modeling the Memory Search Process In the FRAN model, Anderson and Bower (1973) noted that when you want to recall a certain memory, there must be something coded in LTM that identifies the body of content that is your target, distinguishing it from other, unwanted, content. Otherwise we could not recall the material we wish to recall—and memory would be a pretty random process.

Earlier models had assumed that, for a given memory, the information that was coded most strongly would be retrieved. These were called “strength” theories, and were rejected on the basis of the 1970s research.

(This may be why psychologists often avoid the term “strength” when dealing with the potential for LTM content to be recalled. But it is an intuitively straightforward term, and I like to use it.)

Is the strongest element in a memory the one that will be retrieved, or can we override strong codes in favor of a perhaps weaker target?

Bower and Clark (1969) required their participants to learn a series of random words by embodying them in sentences. For instance, HAT might be woven into the sentence, “The man wore a tall black hat.” It was found that at the time of recall the participants could distinguish the target words (HAT) from other words in the sentences (MAN, etc.), although there was no reason to assume that the targets reflected stronger codes than the other elements in the sentences. The conclusion was that we do indeed designate particular, desired content in some fashion.

The issue can be readily described within the context of natural memories, too. Suppose a young woman, Jane, goes for a country walk and encounters a goat, clearly a young one, that comes to the fence around its pasture.The animal allows Jane to pat it through the fence, and raises its head to display its large yellow goat eyes. This creature was by far the most strongly coded element in her memory of the afternoon. But if Jane is asked,“Did you see flowers in pots on that big stretch of land at the top of the hill?” she should have no difficulty in replying. Perhaps there were no flowers. Thus, we can clearly recover target information that is not the dominant element in a memory.

Any adequate model of human recall must account for this phenomenon. In FRAN, the issue was handled through the concept of list tags. Here FRAN would enter the lexical component (i.e. the vocabulary) of LTM, and then travel from that point via the available links through the network, searching for items on the target list. In other words, activity would travel through the net. The spread of activation here was seen as being essentially random, although in some cases a link might be designated a “good path to follow.” As each word in FRAN’s lexicon was reached, it would be checked

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for a tag. The tags had been created during the learning process, and indicated whether a given word had been on the list. For instance, if APPLE had been a target item, the APPLE node in LTM would be tagged with the information “present on List X” (X would be designated in the form of context). FRAN would retrieve an item if it had the right tag.

The random movement through the network was described as a “search.”

This raises the critical question: does human memory in fact identify the nature of its content, and so desired targets, on the basis of specific information, whether described as a tag or not?

The Bower and Clark study outlined above cannot fully clarify the issue, because the task of distinguishing a target word from an entire, nontarget sentence is clearly different from the task of memorizing a list of words. In the latter case, every item is a target. Thus, different cognitive processes are likely to come into play in the first task as compared to the second—particularly if it assumed that the memory function operates in an adaptive, “intelligent” way. (The study did indicate, though, that the memory function can designate specific information as a target, when this is needed, and may do so routinely.)

A second, wholly critical, issue concerns the role of cues. It was mentioned earlier that cues strongly activate the information in LTM that they contact. In fact, their influence is so marked that the contacted information normally dominates other content, in terms of potential retrieval. This is the case even when the background activity level of this material is not particularly high. As a result, the information contacted by cues will— briefly—be the most strongly coded of all the information in a given memory. When Jane is asked, “Did you see the flowers in pots on that big stretch of land?” the question embodies a cue that will result in the flowers-in-pots content becoming (for the moment) the most highly activated element in her recollection of the morning—more so even than the yellow-eyed goat.

Ironically, it seems that the original strength theorists were right after all.

It should probably be mentioned that the spreading activation tradition has conceptualized the effect of cues in terms of increased activity level (of the material that they contact), as described above, and this may well be the correct interpretation. But other possibilities also exist. For instance, it could be the case that when cues contact information in LTM this moves that information into what can be conceptualized as a special processing channel, which is designed to retrieve content into awareness. Under this view, the effect would also operate for material contacted by the cues in LTM, on the basis of spreading activation within the net.

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Accessing Long-Term Memory Content Through Headers What follows forms the basic—if somewhat minimal—skeleton of a theory that will be pursued in the present book. It can, at least, be applied both to random word learning and to natural events. A critical concept here involves what is being called a header.

When an individual learns a list of words, a concept is formed of the list, as suggested above. It might be understood as, “The list I learned in Room 110, as part of an experiment; the list I learned on Monday, the first list of this kind I have memorized; the list I learned that day it rained so hard”— and so on. But the memory function will include what could be termed a summary or descriptive header, coded during learning into LTM itself. This should involve the most fundamental comprehension of the thing represented. It would be something like, “The List I am Learning,” which with time would transmute to, “That List I Learned.”

The descriptive header, then, is coded into the long-term store. The act of learning involves the forming of associations with the header, with the associations leading to the items on the target list.

There is evidence from autobiographical memory that we do indeed generate headers for the sets of information that we code concerning our lives, as well as further proof from daily experience (Barsalou, 1988; Burt, Kemp, & Conway, 2003; Conway, 1995, 2005; Linton, 1975). We use them too in the act of communication, and seem to generally converge on the same kind of phrasing. For instance, at the time of the test the experimenter is likely to say something like, “I want you to recall that list you learned on Monday.” As a header, this appears to make sense both to the experimenter and to the participant.

Thus the experimenter’s request provides the cues needed for recall. For the participant, the request becomes both a set of cues and a goal: “I want to recall that list I learned.” Thus, the cues will correspond to the descriptive header (“that list I learned”) formed in LTM at the time of learning.

Under the present view, access is achieved on an identity basis (between cues and the header in LTM), and the memory function “goes” directly to the target material. Once the header is activated, the associations formed during learning, between the header and the words on the target list, will play through if they are at sufficient strength. If this does occur, the now highly activated memory content (the items on the list) will be retrieved.

This is how access is achieved into the long-term store, and how we are able to recall a target memory as against one of the vast number of nontarget sets from that store. It is not achieved in most cases via context, nor

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is it achieved by reading a tag. It simply involves a match between a cue or cues and a descriptive header. Once the header is activated, this will lead to the activation of the target material via (header → content) associations formed during learning. Just how these associations are developed constitutes a major topic in Chapter 3.

Some Questions To summarize the material presented above, a question that any model of human recall must answer involves explaining how a target memory can be distinguished from the vast number of memory sets present in LTM, such that the desired memory is retrieved. This is effected by means of cues, which specify that memory, and the fact that the cues will correspond to a header in LTM if the target information is in fact present. Access then occurs on an identity match basis. The memory is the body of information subsumed under the header. In fact, as will be seen, this form of access does not always work perfectly, but it does work.

The second question concerns the retrieval of the target memory.

Since cues appear to supply some kind of particularly strong activation to the material that they contact, that material (even though it may reflect a relatively weak memory compared to others) becomes the most highly activated at the time of retrieval, and is therefore retrieved. It is in this sense that the original strength memories could be described as correct.

Something that becomes noticeable here is the extent to which memory codes show more flexibility than language. If a participant hears, “I want you to recall that list you memorized,” “I want you to recall those words you memorized,” or “I want you to recall the items you saw during Monday’s experiment,” then the same idea will be conveyed, and the appropriate cues generated. The memory function appears to have no difficulty in registering that all the statements listed above refer to the same thing.

Although the assumptions described above, concerning cues and headers, are not normally spelled out, they underlie most current models of memory involving computer simulation. For instance, the approaches to order recall described in Chapter 3 almost all implicitly posit access from cues to target memory on an identity basis, as do FRAN’s many descendants.

Intriguingly, I have noticed that some authors still refer to descriptive headers as the context for the list. This seems to be just a kind of historical shadow: there is no indication that environmental stimuli—actual context, things outside the nature of the list itself—are posited. Perhaps if a term has been around long enough, it gains a kind of legitimacy, and simply continues.

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MEMORY RETRIEVAL AND SPECIFICATION CUES The material above leads to the idea of specification cues. As the term is used here, a specification cue is a summary description of some desired memory content—or, to put it a little differently, it is an exact specification of that memory. “What happened at dinner last Friday?,” “Where is the wellhead on your land?” “Do you know whether lilacs can survive in a hot climate?,” or, of course, “That list I learned,” and so on. From this viewpoint, at any time when we deliberately try to recall some body of memory content, our cognition generates specification cues; as described above, these correspond to the descriptive headers in LTM—if the desired information is indeed coded in LTM. Other factors, such as, for instance, contiguity links relevant to the learning environment, play little, or more often no, role. The specification cue is the lion here; it is the true causal force in the work of retrieval.

As described above, there was a period when it was posited that environmental stimuli were indeed influential in determining recall. From this point of view, we forget across time (as we surely do forget) because the stimuli present during learning change across time. But this view no longer holds when it is posited that the critical agent that provides entry into LTM, and contact with a target memory, is a descriptive header. These do not change across time. It seems that other causes must be sought for the hard fact that we do forget information with the passage of weeks or years.

That a specification cue may find its target (if there is a target) does not mean that the memory will be recalled.This second factor depends on the strength of the associations formed between the descriptive header and the desired memory content, as well as the background activity level (strength) of the memory itself.

The opposite view was popular perhaps from the 1960s to 1980s: if the memory function could “find” the target, then the target would be recalled.

But this does not seem to be the case. Suppose after a year a participant in a word-learning study is asked to recall that material. He may not remember a single word. But if he does remember that he learned a list, as a fact, the header is still present in LTM and can be accessed (if not, he would be unaware that he had ever participated in the list-learning event). But the associations with the header are too weak for recall to follow.

When I opened this chapter, I had decided not to use the term header as I have used it above. I later changed my mind because the word does at least give a good intuitive idea about what it is meant to denote. But “header” may imply a large body of material, and this is not necessarily the case. A descriptive header can be any information that subsumes other information.

That is, it can encompass a large body of content or a very small body of

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content. If I am asked, “Did you see any pink rocks on the beach?” then the specification cue is aimed only at information concerning pink rocks, in a certain location. This is not likely to involve extensive content.

A further important point is that a header is not a separate kind of entity from the general content of a recollection—not at all, for instance, like the title of a book. It is part of the target memory content. But it has information subsumed under it, and it indicates the presence of that information.

Also, as suggested above, it appears that any component of the concept formed during learning, and which is deployed as a header, will provide the appropriate access. For instance, “Those words I memorized” will be part of the “That list I learned” complex.

Specification Cues in Everyday Recall Incidentally, following the previous paragraphs, as an exercise concerning specification cues, I asked myself whether I could recall pink rocks from a visit to a beach at Galveston. The first sense I had was: I don’t think so.

My memory had perhaps failed to find “pink rock” information (a header) within that context—there had been no match. But the cues kept going.

The noticeable thing about the question I had posed myself was the fact of unusual color—rather than of rocks. Color must have begun to operate as an idea here (whether as a cue or just a process of spreading activation) because I next recalled that I had seen blue shells on the Galveston beach.

Images followed. Next came a memory of a pinkish rock found on a shore in Massachusetts. It was really a large pebble, with a compound of pinkish and yellow-white color; I could see it clearly in the act of recall. At this point—my memory was starting to provide information concerning where the blue shells were now, having been brought to a relative’s apartment—I shifted my attention back to writing this chapter!

Note how nonrandom the process of spreading activation tends to be, even for the most casual effort. “Unusual color” leads to memories involving unusual color; a search for a pink rock at Galveston may throw up a pink pebble from Massachusetts.When you fail to recover the correct target (perhaps because there is none), other related material is likely to appear instead.

So a “header” can be any information at all. An astonishing thing about human memory is that it can tap material from the most generalized to the most specific. It seems that all content in the long-term store shows associations with the relevant subset content. I can think about an entire, 5-day journey, retrieving (probably in temporal sequence) a huge number of events, or I can (if the memory is recent) retrieve just the events of the last day or just the

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moment when I caught my sneaker on a nail. At every level, there are subset links from the descriptive header to the relevant material. How this is achieved, even by the formidable capacity of the human brain, is difficult to imagine, for the number of associative, apparently overlapping, links, must be very large.

A final point for this section concerns the associative links that operate between awareness (working memory) and LTM. Under the present model, they would probably have to only involve identity relations, as posited by Tulving (1983). This is the case because the cues determine the contact with target, as against nontarget information.Thus, if you want to recall a house on Rose St., it would not be functional if, say, a contiguity link played through and you recalled instead a large oak that happened to be positioned next to the house. Links other than identity could come into play within LTM, once the target had been contacted, but they would not be very adaptive in providing the original access.

Headers and Memory Intrusions When a list of words is recalled, it typically happens that, in addition to the items on the list, which are remembered correctly, participants report items that were not on the list (McGeoch, 1942; Melton & Irwin, 1940).

Sometimes (not always) the items appear to come out of the blue: there is no apparent reason for retrieving them. Further, this outcome generally occurs without awareness that the items are not correct. The long-established data on this point suggest that a careful test, or reading of a tag such as “present on List X,” is not a prerequisite for retrieval in the case of list memorization.

As described above, when a header, such as List X, is contacted, it appears that certain associative functions come into play and begin to activate the items on the list (as coded in LTM). Once activated beyond the threshold level, these items are retrieved.The participant has reason to believe that the material being recalled is the target material, since in most cases this is true.

(Also, it feels that way.) It is widely assumed that the mysterious intruding items (as against those whose source can be identified) are recalled because they reached a high level of activity at the time, due to what is called random noise or random fluctuations of coding strength within the system (Burgess & Hitch, 1999; Estes, 1972, 1985; Houghton & Tipper, 1994).

This interpretation does not mean, however, that more exact information concerning list membership is not coded: it means only that there is a function that “throws up” material on an associative basis after a header has been contacted.The function here may be relatively dominant. But, as noted earlier, it does not mean that other processes cannot also be in play.This issue is examined later.

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Anderson’s ACT Model The early FRAN model of spreading activation was later developed across a series of computer simulations, beginning with ACT (which stands for Adaptive Control of Thought) in successive forms A, B, C, D, and E, and later ACT* and ACT-R (Anderson 1983a, 1983b, 1989a, 1989b, 1990; Anderson & Schooler, 1991; Anderson et al., 2004; Byrne & Anderson, 2001). ACT-R is primarily concerned with reasoning and how different cognitive functions interact, but also has implications for recall and recognition. The various embodiments of ACT encompassed not only spreading activation, but also the opposing function: interference.

Across these progressions, early tenets that had proven to be incorrect were abandoned, and some critical new insights were developed. The assumption in FRAN that the system enters LTM and then moves randomly along links from the entry point was dropped. All such movement is nonrandom: the memory function activates links leading from the point of entry to other material, and these links are geared to produce useful content. For instance, they will lead to content similar to, or otherwise related to, the information contacted by the cues. A second important theoretical position (with supporting data) was noted in Chapter 1. In those cases in which there is a body of extended content, new links can be formed more easily—retention is better—than occurs with isolated facts, or sets with less extension.

A third aspect of the ACT model involves the rejection of any spatial organization in LTM (Anderson, 1983b).

Many earlier spreading activation approaches had assumed that certain representations must be nearer to, or further from, other representations in the long-term store (Collins & Loftus, 1975).Thus, SPARROW and BIRD, as concepts, might be considered to be close together since the former strongly and quickly activates the latter. But in fact there is no spatial organization in LTM. The strength and speed of activation depends uniquely on the strength of the links between different representations or bodies of content—a situation not always easy to conceptualize. For example, in my case I once asked for the name of a certain tree and was told, “That’s a tulip tree. That’s rubbish.” I did not share this opinion, but the statement was surprising enough to make an impact, such that now if I encounter “tulip tree,” I promptly recall, “rubbish.” But there are no elements in my LTM that are close associates of each of these words, and also close associates of one another, as would occur if the organization were actually spatial.

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EMPIRICIST VERSUS CONSTRUCTIVIST VIEWS OF MEMORY The two great philosophies concerning human cognition, empiricist and constructivist, view memory differently on the following point. For the empiricist, memory involves a copy of perception, with what might be described as a minimum of other functions (other than the direct images of perception). There are associative links connecting the memory content.

For the constructivist, even after the complex processing work involved in perception is finished, the memory function will be engaged in generating other codes: the imagery will be interpreted and entirely new cognitive elements will be generated. This occurs at a nonconscious level. Thus, the data supplied by the outside world will undergo transformations, based not on an attempt to duplicate the properties given directly through the eyes and ears, but on other (highly adaptive) functions provided by our cognition. In short, there will be an enormous engagement of cognitive activity, outside of awareness: more than—thread-like—links are involved.

These background assumptions lead to tendencies for some psychologists to prefer a model of memory in which the relevant content more or less faithfully reflects perception, and in which cognitive functioning is minimal, versus a leaning toward the transformation of content and the view that cognitive functioning related to memory is complex, and not directly apparent.

The following material relates—although the reason for this may not be immediately obvious—to the issue outlined above.

Hard-Line Empiricism As the notion of links was originally conceived, a link connected one memory representation with another. Under the Ebbinghausian model, which is a hard-line empiricist model, when we hear or see items on a list, we connect them together on the basis of a contiguity link (i.e. we experience each item in contiguity with the next item, and so on).

Given that Ebbinghaus worked with nonsense syllables, the learning of the series: WOL HYF MIR KUG YOT involved seeing (or hearing) WOL and HYF together, and HYF and MIR together, and forming links (called threads) between them on, again, a contiguity basis; as well as weaker, remote links between WOL and MIR; and yet weaker links between WOL and KUG, and so on (Ebbinghaus, 1885/1964). The resulting phenomenon in memory would thus be:

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WOL—HYF—MIR—KUG—YO Or, more exactly, given remote links: WOL—HYF—MIR—KUG—YOT Today, models that explain the sequential recall of items based on the assumption of links between the items are known as chaining models.

Approaches that also include remote links, as an explanation for such recall, are called complex chaining models (Henson, 1998).

When we recall a list of words, we typically recall them in roughly their original order. The material below describes how this ordered recall was traditionally understood and current questions concerning the accuracy of the older view. The question of the order in which memory content returns to awareness also extends, though, to natural or episodic memory. If asked about a plane trip I took yesterday, the content of that event is likely to return to me in temporal order: what happened at the airport, what occurred when the plane was boarded, what followed at take-off, and so on. So the issue here concerns how the memory function moves from one constituent of recall to the next.

Questioning Empiricism Returning to the list of Ebbinghausian items, is it really the case that WOL becomes attached to HYF, and HYF to MIR, down the series? Does each entire constituent get threaded to the next entire constituent, perhaps, or the tail of one to the beginning of the other (i.e. the final neural activity of one item to the beginning neural activity of the next item). However this might be imagined, it seems that some psychologists began to question the model quite a while back. Are there really threads (even conceptualized as neural activation) connecting item to item directly—or is something else going on? There was no debate about the fact that if WOL and HYF are in fact strongly linked, then the activation of WOL will lead to the recall of HYF. Rather, the question centers on how this occurs.

Baddeley (1968) developed a series of items for short-term recall that alternated in confusability (items that sounded alike) and nonconfusability (items that didn’t sound alike). In short-term memory, the primary code is phonemic (based on language sound), and similar sounds create interference effects.

An example of the lists composed by Baddeley would be: BMGQTJ. (B, G, and T all possess an /ee/ sound and produce mutual interference effects.) Using this type of material, Henson, Norris, Page, and Baddeley (1996) later examined

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several phenomena. It emerged that, as would be expected, nonconfusable items were recalled better than confusable items. However, the critical finding for the present book was this: recollection of a given item was generally independent of whether the previous item had been recalled. Under a chaining theory, this outcome would hardly be predicted.

To translate the finding into the recall of a series of words, in a string such as BOY ROSE TIGER LIGHT HAND TREE, forgetting TIGER would not make it more likely that you would also forget LIGHT. Equally, recalling TIGER would not make it more likely that you would recall LIGHT. So a direct link between the words was clearly not critical in determining recall.

Other data have indicated the same pattern. It is also consonant with familiar aspects of episodic recall. Weak episodic recall is characterized by gaps. You remember some part of a car trip, then forget what happened next, but recall another episode from later during the trip. Of course, other variables could be at work to explain this phenomenon in the case of personal episodes. Even so, when it comes to the human ability to recall content in sequence, if memory content is not directly linked in the case of verbal items (but something else is happening), then this will almost certainly be true of other forms of material, such as your memory of going to Minnesota (last summer) or of your dog developing car sickness (yesterday).

It might be posited that when an item is not recalled, some representation of the item is still there in LTM, and it is this submerged representation that provides a link to the next item. For instance, TIGER may not be capable of being recalled, it may be activated at a nonconscious level and pass “normal� activation on to LIGHT. This remains a possibility. However, other explanations have been advanced and successfully modeled in the form of computer simulations.

Suppose there is a stretch of your memory for the Minnesota trip mentioned above. It involves a dark station platform where sounds rattle against a glass roof. Then you see the lights of the train approaching and hear the noise, ending in squealing brakes. According to a chaining theory (here involving temporal links), recollecting the dark image of the platform led you to recall the appearance of the train lights, because the earlier images were directly linked to those that followed. But if chaining theory is wrong, then another explanation for this steady movement of memory content must be found.

Chapter 3 provides various models that explain our ability to recall things in an ordered series, but without the assumption that the memory

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content for, say, the first of these elements becomes directly linked to the memory content for the second, and so on.

The focus of interest here is not word or letter or phoneme recall. As suggested above, it is likely that the principles that underlie such recall can be extrapolated quite exactly to recollection in natural contexts.

Years ago, it struck me that the functions I had been calling links were more like scoops. They were entities that picked up memory content, and held that content available for recall. But, to aim for exactness, “links” involve several properties (e.g. increasing the likelihood of an item’s recall, or strengthening it, the leading from one item’s activation to another item’s activation, the providing of information, etc.) and no single descriptive word appears to cover them all. These properties, and a new attempt at naming, will be introduced in Chapter 3.

Beyond Empiricism The model of access into LTM offered in this chapter is the model endorsed in the present book, and will be pursued in later chapters. A figure illustrating this approach, and some of its tenets, is shown in Fig. 2.2.

Critically, these assumptions are expected to hold for natural memories, as of daily events, no less than for the recall of words from a list.

A Barrow Memory Some months ago I was reading a novel and came across the word “barrow.”

I then recalled an event from the distant past. I would have been about 12 years old. We had gone on a school trip to see burial mounds. We were standing around outside, presumably near a mound, and the weather was cold.

These mounds were called “barrows.” That identity relation (the word “barrow” in a book to an event involving “barrows”) had opened the memory. But why? I do not usually jump to episodic memories as I read phrases in a book.

I think we were standing in a small group. What I recalled, though, the part that came back first—quickly followed by the context described above—was another girl. She was not in my class but in another of the same age level. She had fine, light brown hair and she was grinning. She said, “What are we going to see, miss? Bones?”

She was grinning because of the “bones” element. I had never seen a smile quite like it—very broad and showing a row of little teeth and an entire line of pink gum above the teeth. The teacher responded negatively.

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STM

Retrieval Goal: I want to recall that list I learned

LTM

Header: “That list I learned.”

Target memory: Items on the list

Figure 2.2 Model of access into LTM. A retrieval goal in short-term memory (STM; e.g. I want to recall that list I learned) accesses a header in long-term memory (LTM; e.g. that list I learned) via an identity link. The header provides specification cues that are associated, via subset links, to the target memory (e.g. the items on the list). The subset links may be in the form of contiguity, similarity, temporal, or other types of links. Each target memory has a particular level of strength, compared to the background activity level, which influences the probability that it will be recalled against nontarget material.

I don’t remember which teacher it was, but I do recall that she was one of the young, pleasant ones. So her response was unusual.

It came to me next that she told the apparently annoying student to get back in line. But no—that can’t have been right. We were standing in a group: not a line. And formal as we were in those days, I don’t think we would have formed a line outside a barrow.

I was mixing up this memory with another. The other showed a number of similarities with the present recollection. It was a school memory,

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from about 3 years earlier (and a different school, the High Street school) in which a question had been asked by one of the pupils, of a young and very popular student teacher. The teacher—most unexpectedly—had been negative. She simply told the girl to get back in line. I had retrieved, and briefly incorporated, the “get back in line” component into the barrows memory.

I tried while writing this to recall more about the barrows episode, but nothing came back. What did occur, though, were further memories concerning the student teacher, and another recollection entirely that concerned standing in line in the High Street school. It involved a friend called Rosalind.

With the original, involuntary return of the barrows memory, some of the cues that had come into operation were: “school context”; “waiting”; “waiting to see barrows”; “outside”; “cold”; and “young teacher normally pleasant not being pleasant to pupil.” This was the information I had remembered at that point.

The combination of “school context, waiting, pupils, young teacher normally pleasant not being pleasant” matched well with an event from some 3 years earlier, at the High Street school. The High Street memory was then retrieved. But the cue-memory match was only partial. It did not include the fact of visiting the barrows, or the outdoor scene, and so on.

So a memory can return when it matches only some of the present cues: even when the alternative, perfectly matching, episode is also available.

(Note that these phenomena fit with the “descriptive header” assumption for access described above.)

I believe there is a reason, in addition to the partial-match phenomena, why a nontarget memory returns on occasion. Obviously, the strength of the memory is critical (a stronger partial match episode may return before a weaker full match episode). But the variables that may provide particular strength to an episodic memory need to be examined, and they appear complex enough to require more space than is available here. For instance, I don’t believe either of these small episodes had ever been rehearsed or recalled until I read the word “barrows” in a novel.

I met Rosalind at a reunion lunch recently. I wanted to know if she recalled the episode when we had been standing in line at the High Street school. She had no recollection of this at all. She asked, in turn, whether I remembered the day we had picked apples from a tree on someone’s land and the angry tree owner had appeared. I didn’t.

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CONCLUSIONS I gave this chapter and Chapter 1 to a friend, who is a good critic and has no academic background in memory.

After reading, she told me that, as far as she knew, her own thoughts did not jump from content to content on the basis of identity or similarity relations. She would not read a word like “barrow” and then have a barrows memory.

About a week later, she contacted me again with the following description. “The other afternoon I had worn a pair of shoes in the garden. I took them off and put them on a table. It struck me that I shouldn’t put dirty shoes on a table. I then remembered going to a particular small store when I was about 11 years old. I’d bought some bottles of cleaning fluid for my mother, and the man who ran the store told me I should not put the bottles directly on any furniture, as they could mark it.”

Her conclusion was that her mind did jump from content to content based on identity or similarity relations, and that she had never noticed this until she mentally watched for it.

The memory was also of particular interest in that the link had operated across a period of 50 years.

Also of interest, the link had not been the literal “you should not put shoes on a table,” but the more generalized, “you should not put things that could mark, on a piece of furniture/a table.” So, the events apparently involved: dirty shoes → dirty things should not be put on a table → they might mark the table → episode involving cleaning fluid that was also something that should not be put on furniture, since it could mark the furniture, with the matching element in LTM dating back half a century.

CHAPTER

3

Processing Structures Chapter 2 examined how we enter new information into memory based on a form of header or brief description of that information. The present chapter focuses on a model of the events that occur during learning, that is, the functions involved in linking the relevant information to the header.

RATIONALE FOR PROCESSING STRUCTURES One of the most deeply researched topics in human memory involves the recall of a list of verbal items, such as words. When an individual learns and recalls a list of this kind, the most common pattern is to recall the words in their original order—with some errors (McGeoch, 1932, 1942). This tendency can be understood as the use of a highly effective capacity that we develop across childhood; in fact, tests for the ability to see and copy several actions in the sequence in which they were seen is one of the basic elements of intelligence testing in young children. What is involved at a general level is the capacity to remember not only actions but also objects, entire events, or words, in order. In fact, any effort to recall a word list by moving randomly about in that list does not work well at all. There is something about following the original order that significantly strengthens our ability to recall the target list.

This is hardly surprising, given the essential role played by this capacity in daily life. You couldn’t make a cup of coffee without being able to recollect the order in which you must proceed: filling the coffee pot, filling the basket with coffee, applying heat, waiting until the water boils, pouring the coffee into a mug, and so on. Forget the correct sequence and things would not go well. In the same way, if you want to remember the events of your morning, you will probably start with the time you woke and move through each subsequent small episode in sequence. Thus, how we recall words in a list (the strong tendency toward order recall) offers a model of one of the most critical functions in our daily lives.

As described in Chapter 2, current research has indicated that forgetting an item in a series of items does not impair our ability to recall the remaining letters, words, or numbers. This finding raises some difficulties Human Memory, http://dx.doi.org/10.1016/B978-0-12-408087-4.00003-7

© 2014 Elsevier Inc. All rights reserved.

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with chaining models: the traditional Ebbinghausian view of associative links connecting each item with the next. If under this view a link fails, the memory function should be weakened. It is possible to develop theoretical approaches that still posit links connecting the target items to one another (for instance, remote links, i.e. between nonadjacent items, might play a relatively large role), or to assume that the forgotten word or letter is in fact present in long-term memory (LTM) but simply cannot be retrieved. An alternative view, though, is offered in the present chapter. Here it is assumed that a function is involved that goes beyond associating verbal items (or any other form of information) directly together, in the sense that some of the target content leads on an associative basis to further content, with no other processing being involved.

The approach offered here is that functions that might be described as being “outside” the target content itself are essential for order recall, or indeed for all forms of movement in human memory. Today, a wide range of models have been developed to illustrate how such functions may operate, and the present chapter explores these various approaches. However, one basic idea is present in all: the idea that a form of processing structure picks up content in LTM and provides the associative capacity to move to other content.

Contrasting Models The opposition between the two approaches could be illustrated as follows. I went to see some land a few weeks ago. When I think of the episode now, I remember walking along a road with small trees growing tightly on a hill to my right. I recall the friend who was with me.Then, the recollection involves looking at some water in a ditch and wondering if we could step across it to the land.

Under the traditional (chaining or complex chaining) model, the appearance of the road is connected in my LTM to the appearance of the ditch. Thus, the neural playing-through of the first body of content is directly connected to the playing-through of the next element. In contrast, under the view offered in the present book, there is no place in LTM representation in which the concrete image or abstract idea of the road begins to intertwine (associatively) with the water running beside it. What occurs is a good deal more complex.

As I considered the ditch, in the present example, an extended body of ideas was also in operation, given that all the images were conceptualized by me in a certain way; for instance, “This is land I want to see/might want to buy” etc., and beyond that an entire matrix of personal and social

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knowledge. But handling all this information and understanding how it is related to the capacity to move from one moment in time to another is beyond our science at present. Returning to what happens with a list of word items seems more tractable, and can probably explain or model the basic principles that provide order recall in any context.

Processing Structures and Memory Errors During the 1950s and 1960s, researchers found that a list of items is not always recalled in the original order. For instance, if words belonging to the same conceptual category, such as Sparrow, Robin, Chickadee, and Dove, are presented in separate positions, there is a tendency to recall these items together (Bousfield, 1951, 1953; Tulving, 1966). Highly associated words such as Cat and Whiskers will also tend to migrate to adjacent positions (Deese, 1961, 1966; Jenkins & Russell, 1952). What is happening here, as always in human memory, is that more than a single function is operating, and these functions do not always move toward the same outcome. Under the present view, a processing structure comes into play to code for the order of the words.

There are others that respond to conceptual identity (between say Sparrow and Robin), or to the properties of animals and things (possibly part-whole links). More recently, though, it has been established that in spite of various tendencies that lead to reordering of the items on a list, the most basic pattern is that of recalling the target words in their original sequence, albeit with some errors (Kahana, 1996; Schwartz, Howard, Jing, & Kahana, 2005).

PROCESSING STRUCTURES FOR SERIAL RECALL The following models attempt to explain simply what happens when items are recalled in order, without adding tendencies in other directions. It is a hard enough task to model order recall alone, given that the relevant events appear to be very complex. For instance, in the case of material that is difficult to hold in the memory, such as any string of random verbal items, interference plays a huge, negative role and interacts directly with the capacity to retain the items in their original sequence.

The material in the following sections may be a little inaccessible to readers who are not familiar with cognitive psychology, or related fields.

The next several paragraphs are intended to convey an idea shared by many current models of order recall: an idea that is endorsed in this book. What is presented in the current section can be seen as no more than the barest bones of a theory of this kind; in particular, it does not include many

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properties (particularly errors) that emerge in human recall, and that are accommodated by the more detailed approaches described later. But it should at least provide a basic understanding of the relevant concepts, such that the material presented in subsequent chapters can be followed. In this way, there should be no difficulty if the main body of this chapter (the material within the starred section below) is skipped.

The present model suggests that there exist functions that provide order recall. They can be described as cognitive structures or processing structures. This chapter focuses on our ability to retain items in sequence, but it is assumed that different structures exist to provide other forms of “link” between bodies of content in memory. The present function is offered as one example of the way in which processing structures operate, and as an illustration of their nature—and complexity.

Temporal Models The approach that is probably most dominant today in the case of order recall involves temporal models. It is assumed here that the relevant structures keep track of the passage of time, in the following way. The first item on a list will occur at a certain moment in time, say Time X. The next item will occur at a very slightly later time, and the next at a slightly later time again. Activity begins when the individual begins to learn the list. The structure codes for or establishes a moment in time, Time X, and associates the first item with Time X. The structure then moves on (i.e. activity continues through it, keeping track of ongoing time) to Time X + 1, and the second item on the list is associated with that time. The function continues in this manner down the list. At recall, the original sequence of times is established, and activity moves down through these sequential moments, activating each item on the original list in turn. Sometimes an item is not strong enough to reach the threshold for retrieval. But this does not impair the work of recall, since activity continues autonomously “down” the sequence of moments in time, such that the item following the forgotten item will receive input from the temporal function and be recalled (if coded at sufficient strength) without suffering from the fact that the previous element had been forgotten. Figure 3.1 shows these basic assumptions.

A wide range of models exist concerning order recall. The example outlined above is just one. It has been run successfully, though, in the form of computer simulations to see whether the outcome matches the data from human performance, and the match is good. It is also the case that

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A Learning Phase Sequence:

Item 1

Item 2

Item 3

Item 4

Item 5

X

X+1

X+2

X+3

X+4 Time

B Retrieval Phase Sequence:

Item 1

Item 2

Item 3

Item 4

Item 5

X

X+1

X+2

X+3

X+4 Time

Figure 3.1 Temporal model of order recall. A, When learning a sequence of items, a structure codes each item with a moment in time such that Item 1 is learned at Time X, Item 2 is learned at Time X + 1, Item 3 is learned at Time X + 2, etc. B, During recall, the structure code for this sequence is reinstated according to the temporal order that was coded during learning. As a result, retrieval proceeds sequentially down the list. In the case of Item 4, activation was not strong enough to reach the threshold for retrieval and retrieval proceeded to the next item in temporal sequence, Item 5.

data exist from animal studies indicating a capacity to keep track of time in a manner similar to the functions posited here (Church & Broadbent, 1990; Gallistel, 1990; Treisman, Cook, Naish, & MacCrone, 1994).

As described above, if a list of items including BOOK TREE DAFFODIL HOUSE is learned, then the learner is likely to report BOOK TREE DAFFODIL HOUSE in the original order. The historical assumption here had been that the word items are linked directly to one another, on the basis of contiguity. But it has been established that forgetting a given item does not impair the recall of the next item to any

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significant extent: the individual who forgets TREE is in general just as likely to remember DAFFODIL as the individual who remembers TREE (Baddeley, Conrad, & Hull, 1965). Given this discovery, probably the majority of psychologists in this area believe that the various word items are not directly linked to one another. That is, there is no “thread” leading from the representation of BOOK to the representation of TREE in the learner’s LTM. Owing to these and some related findings, new models have been developed. Researchers, or some of them at least, went back to the drawing board.

If the items are not directly associated together, then it has to be explained how TREE follows BOOK quite reliably. The claim that the functions that provide ordered recall are the same across many forms of memory has been supported by analysis of the errors that occur across different kinds of task. An order error involves some constituent being recalled in the wrong position. The same pattern that obtains in verbal item recall has been found in the case of errors in human speech (Brown & Vousden, 1998;Vousden, Brown, & Harley, 1997). For instance, letters in a given position in a series will quite reliably transpose to the same position in another group (Ellis, 1980; Henson, 1998; Nairne, 1991; Ryan, 1969a, 1969b). Thus, if I am trying to recall GYR BKO XCW, presented as groups of three letters, a typical error would be to recall the second group as BYO, swapping the second letters of the first two groups. But an error that would be very rare would be to swap B and Y—items in different positions across the groups. In speech production, spoonerisms (and many other known errors) appear to reflect the same kind of mistake. An imaginary example here would be the indignant professor speaking to his student: “Not only have you hissed all my mystery lectures, but you have tasted a whole worm!” (first position consonants being transposed on two occasions, in each case supported by LTM in that the changes conform to real words).

The present chapter examines models of ordered recall for words, and other verbal material, and makes the case that a certain kind of approach works best here. The issues relevant to this general theory (of processing structures that come into play to direct the movements of human memory) are revisited at the end of the present chapter in the "Conclusions" section, and all readers should peruse that section. However, the material in the following sections contains a more detailed exploration of the ideas and data, and is intended for those readers interested in furthering their understanding of temporal models. Later in the book, similar ideas will be applied to episodic memory. The question then is of how well they fit.

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THEORIES OF SERIAL RECALL Much of the work on serial (order) recall has been pursued in the area of immediate recall, also characterized as short-term memory (STM). Here, a string of items is presented, and the individual recalls them either at once or after a delay of only seconds. The items have not been learned; they are simply being held in memory for a brief span.

Conrad’s Boxes Model As far back as the 1950s, Karl Lashley had urged that memory items cannot be directly linked together (Lashley, 1951). Pursuing this insight, Conrad (1965) urged an alternative view (alternative to direct linking) within the context of STM. He suggested that each item was coded inside a “box.” At recall, the system steps through the boxes, retrieving the item in each. This process would move forward from the first box (although it could begin at a later point). Thus, serial order recall would be provided by the boxes. It would have to be assumed here that the boxes were linked together, determining the correct sequence. The basic idea is shown in Fig. 3.2.

This was a promising start, but we make mistakes in order recall. A rigid sequence of boxes would not predict this outcome. Also, of all the mistakes, the most common involves two adjacent items switching places; in general, when items do migrate to new positions in the list (as against two items transposing), the new places are close to the original positions (Healy, 1974; Henson, 1998, 1999).

Estes’s Perturbation Model Given these findings, Estes (1972, 1985, 1997), Lee and Estes (1977, 1981), and Lee (1992) developed an approach known as the perturbation model.

Here, it was assumed that target items were not located in boxes, but rather

Sequence:

Item 1

Item 2

Item 3

Item 4

Item 5 Time

Figure 3.2 Serial order recall. Items learned sequentially are fixed according to input order and stored separately in metaphorical boxes that are linked together. During recall, each item is retrieved from its box in a sequential fashion, thus preserving the input order in which the items were learned.

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that associations were established at learning between control nodes—control elements—and the items. Here Control Node 1 would be associated with Item 1, and Control Node 2 would be associated with Item 2, and so on. At recall, activation would travel down the nodes, from 1 to 2 to 3 to the end of the sequence, such that the associated items would also be activated, and in the correct order.

The Estes and Lee model still needed to account for errors in position recall. This was achieved on the basis of the perturbation assumption.

Perturbation involves the view that items shift randomly to some extent, partly due to noise in the system, much as marbles placed in small cavities in a container might shift if the container were mildly shaken. Since the perturbation is indeed usually mild, under the Estes approach, the most common outcome is the transposition of two items; in general, items tend not to move far from their original positions (as error data indicate to be the case).

Models Based on Control Nodes A range of models have now been developed based on the idea of some form of outside factor, such as a control node or control context, that changes as content is entered into memory, and determines order recall (Brown & Vousden, 1998; Brown, Preece, & Hulme, 2000; Burgess, 1995; Burgess & Hitch, 1992, 1999, 2006; Hartley & Houghton, 1996; Hintzman, Block, & Summers, 1973; Hitch, Burgess, Towse, & Culpin, 1996; Houghton, 1990; Houghton & Tipper, 1994). This is the basic conceptualization of order recall shown in Fig. 3.2.

There has been a tendency in research into order recall to favor a timebased model. Here, instead of simply positing the existence of a series of control nodes, it is posited that they (the control nodes) have an internal nature. They code for the passing of time. The basic idea is that the first item on a list is presented, and the next item necessarily follows it at a later time point. In the same way, the third item follows the second at a yet later moment in time. A function that keeps track of this temporal progression could serve to provide the context or state of the system (the control node) to which each item becomes associated. Here, Time X (State 1) would be most strongly associated with Item 1, and X + more time passing (this being State 2) would be most strongly associated with Item 2, and so on. In temporal models, there is of course no claim that an actual time is recorded by the memory function (corresponding for instance to our concepts of “three o’clock,” etc.), but what is coded is simply the passing of time, beginning at some starting point.

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The fundamental concept across these various formulations, however, is that something outside the target material provides our ability to retain sequences in order.

These entities have been described as control nodes, control elements, bins, learning contexts, context states, and slots. When I first noticed something of the kind, I thought of it as a scoop. This was because this “something” has the power to strengthen a representation in memory. In the present case, if, say, Item 3 has received activation from Control Node 3, then it stands a significantly better chance of being recalled (than under a condition in which order recollection was not possible). In short, the item has been “picked up” by the control element, or scoop. It seems that all these terms must be taken as metaphors.

There are two ways in which control elements or slots might function.

First, the outcome of their work could be produced on a strictly physical, noncognitive basis. In other words, there could be a behavioral result (the tendency to recall content in a certain order), but no information present in the system that specifies the basis for this ordered recall. In other words, the system here has no code for “time at start,” “later time,” or “first position, second position,” etc. I believe that most current models favor this view.

The alternative position is that cognitive representation involving order recall does exist within the system; by “the system” is meant the LTM store and its various functions. Here it is assumed that a control node, for instance, not only has an internal nature (which could be a set of unique oscillators) but also has an internal nature that embodies content, and as such is not simply a physical state of the system. This corresponds to Anderson’s (1983b) claim that links carry information.

There exists a large body of data supporting the view that behavioral responses can be decided by strictly physical events occurring among neurons (or within the brain, if the creature in question has a brain).

Conditioning is a case in point, given that Aplysia, a sea snail, can be both classically and instrumentally conditioned (Kandel & Squire, 2001). These data can be seen as supporting a physical model, too, for such events as order recall.

But an alternative case can be made equally well. Aplysia has no ideas and certainly no concepts of temporal or positional relationships. But we do. The question then seems to depend on how “far down” in the system this kind of cognition goes. Given that we clearly do possess such capacities, at some point the physical, neural underpinning must translate into cognitive representation. This is the new thing possessed by creatures with

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complex brains. My own bias leans toward the view that cognitive information is present at a preconscious level, and that the control nodes under discussion here probably code for actual cognitive content. This may be a minority position, though.

A final point may be important. If control nodes or slots do have internal content, if they code for a kind of meaning, then this does not imply that the code is anything like those we experience at a conscious level and communicate in the form of words.

Oscillator Models There exist today a number of time-based (or partly time-based) approaches known as oscillator models. Here the assumption involves an entity, or many entities, that oscillate across time. Time is marked—kept track of—by these oscillations.

Burgess and Hitch (2006), developing a connectionist, oscillator-based model, described the various states as “internal context signals,” and noted that these had some properties that could be described as temporal, but also some that should be described as event based. The temporal aspect involved the pattern of the different signals following one another through time. But, under this model, it is the presentation of the item (an event) that triggers entry into each new (internal context) state, and not the temporal moment when each item appears. For instance, an item could be presented at the rate of one every 30 seconds, or of one every 2 minutes, and the critical factor (causing a change in context state) would not be a set amount of time between the appearance of a given item and the next item in the series, but the fact that it is, precisely, the next item. Thus, if a word is presented every half-second, the system could be operating in such a manner as to form an association following each half-second in time. Under the Burgess and Hitch model, the association would only be formed on the appearance of a new item. A somewhat similar model has been offered by Anderson and Matessa (1997).

POSITION CODING FUNCTIONS IN SERIAL RECALL There is a great deal of evidence supporting the view that the memory function codes for the position of items on a list. For instance, if a series of letters, say BXRDGVTNF, is divided into subgroups, for example BXR DGV TNF, then immediate recall improves overall, but one kind of error

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Group 1

Group 2

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Group 3

Pos. 1

Pos. 2

Pos. 3

Pos. 1

Pos. 2

Pos. 3

Pos. 1

Pos. 2

Pos. 3

B

X

R

D

G

V

T

N

F

Figure 3.3 Transposition errors in memory for a series of letters. A series of letters are remembered in groups of three, with memory coding for the position of each letter within the group. A common recall error is for letters occupying the same position in different groups to swap positions. In the present example, the letters occupying Position 2 in Group 1 and Group 2 become transposed such that BXR DGV is recalled as BGR DXV. This transposition is considered to result from response competition between the Position 2 items such that the Position 2 → G association for Group 1 is stronger than the Position 2 → X association for Group 1.

increases. The error is this: as described above, items in the same position, in different subgroups, tend to swap places. Thus, the series above might be recalled as BGR DXV TNF (Henson, 1998; Ryan, 1969a, 1969b). What seems to be happening is shown in Fig. 3.3.

These data clearly suggest that a function coding for the position of each item in a series is established, such that each position is associated with a target word or letter (perhaps without time-passage information, or perhaps working in concert with time-passage information). Thus, the “control nodes” here could reflect position, with activity moving down through Position 1 to Position 2 and so on throughout the series. In the case of grouped items, such as BXR DGV, the memory function would identify headers such as “Group 1” and “Group 2,” and return to the First Position node for D as DGV was presented, and the same for the T of TNF. In the example shown above, in which BXR DGV transposes to BGR DXV, Position 2 in Group 1 has become associated with both G and X, such that the system may confuse these items in the process of recall. (This could be seen as an example of direct response competition, with the Position 2 → G association being stronger at the moment of recall than the Position 2 → X.)

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Position Coding Errors In further support of the hypothesis of position coding, there is also evidence that when a series of lists are learned, errors may occur on the basis of items switching position across the lists (Conrad, 1960). For instance, the item in Position 7 on List 1 may swap places with the item in Position 7 on List 2 (more often than should occur by chance). In the case of these loner lists, involving learning as against immediate recall, there is also a tendency for the position codes to weaken in the middle of the list, thus producing more errors, very probably due to interference effects (proactive interference from the beginning of the list and retroactive from the end of the list).

Under this view, the small effect of failed recall of any given item is explained in the same fashion as with temporal models. Activity moves down the structure providing position recall, from control node to control node, and activates the remaining items in the series in an ordered sequence.

It is also possible to see position information as being provided by an oscillator function, as extended from the direct mapping of passage of time to that of mapping position.

The Associative Hypothesis Oscillator models and/or other control node models handle the problem of errors in order recall primarily on the basis of the following assumption. Any given control state is associated most strongly with the corresponding item (State 1 with Item 1 etc.), but is also associated, although more weakly, with the other items in the series.The association is strongest for items close to the one currently in the focus of attention, and weakens progressively for more remote items (e.g. State 1 is associated with Item 2, more weakly with Item 3, even more weakly with Item 4, and so on).The basic idea is shown in Fig. 3.4.

There are two major sources of order errors in human recall. One, as described above, involves the fact that items that are close together not infrequently switch positions, and indeed nonadjacent items may also transpose. This phenomenon is handled by the associative hypothesis described in the last paragraph.

Coding Similarity The other source of error involves coding similarity. This second factor can be described as a classic interference effect. If the target items in a series are similar to one another, similarity-based interference occurs. In immediate memory the dominant code is phonemic, such that items with phonemes

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Oscillators Slow Oscillators

Learning-context vector

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Item vector

Π Π Π

Π Fast Oscillators

Π

Figure 3.4 Oscillator model of order recall. Ordered recall of a series of items is achieved through a dynamic process in which each item (item vector) is associated with a control node or state (learning-context vector) and a background level of activity (oscillators). Retrieval of the sequence of items, therefore, depends on activation of the control states associated with each of these items and the specific background level of activity for these items. Each control state for a particular item embodies information related to the context of the learning situation for that item. The strength of association between the control state for an item and later items in the sequence becomes progressively weaker through the series of items. The background activity for an item can be influenced by such factors as the amount of rehearsal devoted to an item, the degree of attention used during learning, and (in the case of words) the imagery value. Oscillator models explain a number of error patterns in ordered recall such as those based on similar coding of items. Source: Brown et al. (2000). Reprinted with permission.

that are similar in sound produce impaired item recall, but also, and strikingly, impaired order recall (Conrad, 1965; Ellis, 1980; Healy, 1974; Wickelgren, 1965a, 1965b, 1966). In the case of LTM, where the primary code for a series of word items is semantic, the basis of interference is semantic similarity (McGeoch, 1942). Here, order recall is affected, since items as such can often be recalled based on inference (for instance, if various flowers are involved, plausible candidate names can normally be generated).

Overall, the items most likely to show position errors are items that share coding similarity with other items in the series.

Control node models provide several possible explanations of these interference effects. For instance, it can be posited that the repeated use of

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the same coding element weakens that code, such that an item may fail to reach threshold as activity from the (perhaps temporal) processing structure reaches it. This would produce an omission. Equally, if two items again share the same coding element, the following could occur. Suppose the letters FGYBHT have been presented. An intriguing idea emerging from both the older and the current literature is that the components of a target item may be capable of being associated individually with other items or components in a target series (Wickelgren, 1966). Thus, F would be associated during learning with G, including the individual /ee/ sound of G. Once this association has been formed, it should hold for F → /ee/ in any context. Thus, there is a weak association between F and the /ee/ sound of B. Perhaps something (possibly random noise in the system) operates to activate B more strongly than G at the time of test, thus producing a transposition.This effect could only operate between items with similar phonemes, thus explaining the difficulties that emerge within the context of coding similarity.

Further Factors Affecting Serial Recall It was stated earlier that control state models handle the fact that an omitted item does not break the chain of activation that provides recall across a series of target items. This introduces the question of why some items fail to be recalled. The present approach posits that activity continues steadily through the sequence of control nodes or control states, providing input to each item in order. Clearly, however, this input is not sufficient to activate all the items to the threshold of recall (under typical testing conditions). The assumption here is that each item has its own background level of activity, which combines with input from the control states to determine whether the item will be retrieved. A wide range of factors can influence the level of background activity of a word or letter or number target. Degree of rehearsal is obviously one of them. Degree of attention could be another. Some properties of words (e.g. high imagery potential) also make them easier to retain; yet another factor (to be examined later) involves background associations with other material.

And interference effects provide a major source of impairment in the capacity to recall an item, and also to recall an item in its correct position.

Brown, Preece, and Hulme’s Oscillator Model A specific model of order errors was developed by Brown et al. (2000) on the basis of a temporal, oscillator assumption. The approach is of particular interest in that it provides a tentative explanation for why periods of time

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close to one another are more likely to be confused than periods remote in time from one another.

The same ideas could be extrapolated to other cognitive representations in which certain elements seem to be “more similar” than others. Number would be one example. For instance, you might recall journal volume 16 as volume 17 (as I did recently), but probably not as volume 50.

In the Brown, Preece, and Hulme hypothesis, the movement of oscillators codes for the passage of time, such that they would be in a certain state as each target item was presented. As in the basic control-node approach, activity moves down through the various control states, associating each new item with the current temporal state. In this approach, order errors (i.e. transpositions of items) can be explained as follows. The oscillators move at different rates to keep track of different aspects of the passage of time.

This approach parallels the situation with the two (and sometimes three) hands of a clock. The large, hour hand notes relatively extended periods of time (two o’clock, three o’clock, etc.), while the small hand notes subdivisions of those longer stretches, such as minutes, and the second hand even smaller subdivisions. In the present model, four oscillators work to provide a unique control state or “learning context” to which the current item will be associated during learning. In fact 20 context states are developed to represent the time state obtaining as each new item is learned.

A critical idea in the present model is the following. A given moment in time, as coded by the oscillators, is relatively similar to the moment in time that follows it, and slightly less similar to the next moment in time again, and slightly less similar again to the next moment in time. In short, the time code—the type of movement of oscillators, or however the representation of time may operate—has an internal nature, with the capacity for varying degrees of similarity with other temporal states. Several effects follow from this.

For purposes of explanation, imagine the time states to be symbolized by letters. State 1 might be ABCDEFGHIJ. State 2 will be nonidentical, but similar, to it. State 2 might be EFGHIJKLMN. As the system moves to State 2, EFGHIJKLMN will become most strongly associated to Item 2, and so on down the list.

Critically, the elements EFGHI (a subset of the constituents of State 2) are now associated with both Item 1 and Item 2. They are present in both states. This means that State 1, which includes EFGHI, has become associated not only with Item 1 (most strongly), but also with Item 2 (a little less strongly). In other words, given that the elements EFGHI have

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State 1

Time-State Constituents: ABCDEFGH

State-Item Associations:

Item 1

State 2

State 3

State 4

EFGHIJKL

GHIJ KLMN

CDEF GHIJ

Item 2

Item 3

Item 4

Figure 3.5  Shared associations among states and items.  The functions that determine the order in which items will be recalled are shown. Oscillators working together to code for time, generate State 1 at the beginning of learning. Activation moves from the beginning states created at learning, across the subsequent states, such that a series of time-state constituents are associated with each item. Further, the time-state constituents associated with each item overlap with the time-state constituents associated with adjacent items, creating state-item associations. State 1 is most strongly associated with Item 1, but is also associated with Items 2, 3, 4, and so on, at decreasing levels of strength for each item (arrows indicate the associative connections among these items). The same associative pattern holds for State 2, State 3, and so on. At recall, the states play through in order. Each state will generally provide the strongest activation of the item directly associated with it. However, due to noise in the system, items closest to the target are the most likely to be recalled in the original position of the target.

For example, an item at second-remove from the target can be recalled first if both previous items currently have lowered activation due to the noise factor. As a result, items may switch positions at recall from the original order. The figure here shows only a series up to Item 4, but the same patterns would hold for later items.

been associated during learning with both Item 1 and Item 2, whenever a temporal state that includes EFGHI occurs, the relevant associations will play through to both Item 1 and Item 2.

Equally, when any of the constituents of a time state occurs (perhaps, later down the list, GH, HI, LM, or L), and that constituent has been associated with an item, or in fact many items, on the list, the relevant associations will play through.

In this fashion, State 1 will become associated not only with Item 1 but also with Items 2, 3, 4, etc. Each association will be a little weaker than the last. An identical pattern will also occur for State 2, State 3, and so on. (They will each become associated with all the items on the list, at different levels of strength.) The basic idea is shown in Fig. 3.5.

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At recall, the system is typically set back to the beginning state (in the present model, the “learning context”). The various temporal states will then play through in order: State 1 leading to State 2, State 2 leading to State 3, and so on through the series. This provides generally accurate order recall. However, since each state is associated with all the items, “noise” in the system (random fluctuations of associative strength) may on occasion cause a given item to become more activated than the correct next item, leading to recall of that item out of order. This is more likely to occur for words or letters next to the correct target, because in, say, the case of Item 4 (correct target), Item 5 will be the one most strongly associated with State 4 of all the other items. (Those that have already been recalled are inhibited, so in the present example Item 3 will not be recalled again.) Immediately following the temporary effect of noise in the system, however, Item 4 should be the most highly activated item, and so be recalled. The result of all of this is the common pattern of transposition of two items.

A critical datum is the finding, described in Chapter 2, that if an item completely fails to be recalled, then it has little effect on successful recall of the next item. If Item 4 is forgotten, then Item 5 will be the most strongly activated at that moment in time, and will be recalled.

Hierarchical Coding of Order A final property of the present model is that order information possesses hierarchical structure. For a single list, there is an order code for the list as a whole. But if the list is broken into groups, such as AHF Y TR MNB, etc., then there will be a code representing the ordering of the groups: Group 1, Group 2, and Group 3. And there will be a code representing the position of items within each group (Group 1: Item 1, Item 2, Item 3, and so on).

Further, Nairne (1991) reported data indicating that the order code at each level works autonomously. In other words, there is a separate code for each level, independent of the others. The position code for perhaps nine items will run 1–9, while if the items are grouped in threes a separate position code will establish 1–3 for each group.

In further support of a hierarchical assumption here is that individuals learning a list may recall that an item was “toward the beginning” or “toward the middle” of a list although they cannot identify the particular position (e.g. Item 5) of the item on the list. A more general or encompassing position code appears to operate in this case. As described above, more specific position codes have been shown to exist, although these do not generally result in conscious awareness. That is, the individual may not be

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able to say, “That item was in fifth position,” although when two lists are learned, the two items in fifth position may transpose during recall.

The present hierarchical property is of particular interest because a large body of research supports the view that human memory operates in a hierarchical fashion not only in list learning but also in many other domains, including conceptual structure and episodic recall.

Context States As described above, current approaches do not posit that one control state of the system becomes uniquely associated with one item. This would lead to perfect order recall, which Conrad believed did in fact occur. He thought apparent errors in order memory were due to incorrect reconstructions—at the time of retrieval—of items “really” in the correct position (Conrad, 1965). This does not appear to be the case, however.

Various approaches have been taken to address the issue of how the oscillator-derived states become associated with the target items. In the examples outlined above, the emphasis was on each individual context state being activated in sequence. But other assumptions are possible. Burgess and Hitch (1999), for instance, posited a steadily changing shift of activation across a series of control states working together, moving from those at the beginning of the target series to those at the end. Here Context States 1, 2, and 3 might be activated together, with the activation shifting to 2, 3, and 4, and to 3, 4, and 5 across the series.

Across all models of the present kind, however, the states change: one leads to the next.

If context states have an internal nature, such that each has a relatively high degree of similarity with the one that follows, then the movement from state to state could be explained as reflecting identity links.

The issue here is this. It could be posited that State 1 is linked, due to the inherent, genetic organization of LTM, to State 2, such that activation will move from 1 to 2 to 3 in the required fashion. Here you can imagine a connection as much preestablished as one piece of metal riveted to another.

But the view suggested above is that this is not the case. The movement is not hardwired. Instead, movement will occur because State 1 has an internal high degree of overlap with State 2. The content of the two is similar.

Identity links based on that overlap will then produce the movement. This plays back to Brown et al.’s (2000) intriguing notion that in human cognition a time just following Time X will be similar, in internal code, to Time X, while a remote time will be less similar.

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Additional Considerations The models described above posit that any given state of the system is associated not only with the immediately “correct” item but also with other items on the list. Might this seem a bad plan? After all, if the arrangement were one state only per item, order errors would not occur, or would be very rare.

However, if this were the case, we would be able to recall the position of a given target in the sequence but would have no sense of positional relationships over larger distances. For instance we would have no code indicating whether certain items were close together, widely separated, or presented early or late on a list. There is empirical data in support of the claim that we do in fact code for distance information. For instance, if subjects are asked to judge which of two items appeared more recently on a list, they show some capacity to identify this information, and are more successful when the items are widely spaced (Brown, 1973; Hacker, 1980).

Other Approaches to Serial Recall Emphasis in this chapter has focused on models involving dynamic, changing control states, such as oscillator models. It should be noted that many other approaches to the issue of order recall have also been developed.

Some of these support a chaining hypothesis (Elman, 1990; Jordan, 1986; Lewandowsky & Murdock, 1989; Murdock, 1995). Others, as with dynamic changing-states models, posit factors outside of the items themselves as providing order recall, but emphasize the role of the beginning (and sometimes both the beginning and end) of the list in providing computational anchors on the basis of which order information can be established (Henson, 1999; Page & Norris, 1998). Others again explain serial recall on the basis of the degree of activation of each item at a given point in time (Anderson, Bothell, Lebiere, & Matessa, 1998; Botvinick & Plaut, 2006).

CONCLUSIONS It has been emphasized in the present book that information retrieved from memory constantly changes. Traditionally, this shift has been described as the function of links, connecting each set of information to the next. This chapter has focused on one such “link,” the process that generates order recall, since order memory has probably been researched in greater depth than any other form of recall.

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Under the traditional view, bodies of content were seen as being linked or associated together in a direct fashion.The function involved here seemed relatively simple, and is certainly easy to conceptualize: that of forming a connection between two or more elements. But when the large body of our knowledge concerning the properties of order recall is considered (including omissions, transpositions, and intrusions), it emerges that the relevant functions are in fact highly complex. A goal of the present chapter was to demonstrate the complexity of this particular function. A further claim is being advanced here: that movement of other kinds (i.e. other kinds of “links”) involve equally complex functions. These latter remain to be identified.

Processing Structures A term that seems to express this function well is processing structure. Processing structures can be seen as capacities that recognize material appropriate to their nature, provide a shift from the current information to the next information set, “pick up” the next, appropriate, content and strengthen it, and in many (or perhaps all) cases provide information. For instance, in a welllearned list if two words appear together, perhaps APPLE HAT, the processing structure will provide movement from the item APPLE, just reported, to the item HAT; will strengthen the capacity to recall HAT (above what would have been the case had this temporal or positional or order structure not been in play); and in some cases provide the information to the learner that the item following APPLE was indeed HAT. Processing structures are clearly selective. Two entities must be similar for a similarity link (similarity processing structure) to come into play. And encountered material must have the property of “elements occurring one after the other” for the structure that provides order recall to be mobilized.

How the memory function identifies the appropriate information remains unclear. In some cases, such as similarity, the process may be hardwired. But the property of “elements one after the other” seems to imply a more flexible or cognitive-type function.

The present view of memory implies that intricate cognitive processes occur to establish and retain information in LTM, all of which operate at a nonconscious level. Under the present formulation, conscious awareness and consciously generated strategies play a relatively small role.

Temporal Versus Positional Processing Structures It was described above that claims for both temporal and positional structures have strong empirical support. Our capacity to monitor the passage

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of time may strengthen our ability to recall a list of items: the data clearly indicate that in the case of list learning the memory function codes for position information. Thus, a position-processing structure, as against a temporal structure, could be the function that provides ordered list recall.

But a different claim was made at the beginning of the present chapter. It was suggested that the process that provides ordered recall of a list of words may well be, and probably is, the same process that provides our ability to remember the events of our lives in sequence. Thus, if I first drive a car and then enter a café, order tea, receive, pay for, and drink the tea, and next drive to a grocery store, then my ability to remember the order in which these events occurred may be provided by a processing structure operating in the same way as the control state models described in the present chapter.

Several issues emerge here. Position recall is relevant only in the case of content that displays clear boundaries, as words or letters or numbers do, such that you can think of each unit as having a position. This does not conform to the experiences of our daily lives. If John eats breakfast, he will not conceptualize his coffee as being in Position 1, or his getting up from the table as being in Position 2. Thus, while clearly operating in list recall, position codes are not directly involved or implied in the recall of events (episodic memory). And in fact most researchers in the area of biographical recall posit temporal links to explain our human ability to recall the events of daily living in order (Conway 1996; Linton, 1975, 1979). This temporal structure moves from an earlier period in time to a later one, and so to a later time again. I have a personal bias concerning this issue, though: I believe there exists some kind of literal order coding function, which plays the dominant role in both list item and episodic recall. This would be a processing structure that could identify the information, “first constituent, next constituent, next, next, next.” Here, “next” does not mean the passage of time, but rather “there was C, and following C came F. ” Other than this content assumption, the processing structure could be assumed to operate in the way described for temporal models in this chapter.

The hypothesis noted above would not imply that temporal structures do not also come into play in both contexts. As we learn more, it will probably emerge that any and all forms of processing structure that can be applied to pick up Information X will automatically be activated when Information X is encountered, and that all operate together. In support of this view, it could be noted that very weak links between the environmental context in which items are memorized and the items themselves have been demonstrated to exist, as described in Chapter 2. However, the overriding

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processing structure in this form of learning is still some form of capacity to retain items in their original order.

Descriptive Headers and Position Coding It was also described in Chapter 2 that we form descriptive headers corresponding to our understanding of some entity or event. As noted then, the term header is not meant to imply something different from the other content established in LTM: just that it will subsume some body of information (and lead associatively to that information). As will be seen later, evidence of a function of this kind has been described within the context of episodic recall. An interesting example of the tendency has also emerged from research into list recall, as described in this chapter. When a series of target items are subdivided into groups, as with EGF WCY LPO, the memory function identifies the spacing in a way that could be described verbally as the headers Group 1, Group 2, and Group 3, and generates position codes specific to each group.

The idea of headers raises the question of whether, given the establishment of, say, a “List X” header, the items on the list become associated based on a subset link to the header. The material presented here might suggest that this is not the case, since the entire emphasis has been on the operation of a temporal (or perhaps order) processing structure that basically provides our ability to recall the target items—or at least greatly increases that ability.

Subset Links A subset link means a structure that identifies information relevant to the header and associates that information with the header. This function would be expected to operate in both directions, i.e. from the header to the subset information, and also from the subset to the header (a superordinate link). For instance, if I am told that my friend Harry had discovered in himself a talent for music, this datum would be assimilated to my concept of Harry. Now if I am asked about Harry the information about his musical interest will be available (subset link), and if I am asked whether anyone I know has musical talent, I may think of Harry (superordinate link).

One of the central tenets of the present book is that the memory function develops appropriate subset links automatically: indeed, that this is one of the principal characteristics of human memory. The position is taken here, then, that subset links do form between a header such as “List X” and the items present on that list. But lists of random items are difficult to learn and retain; in other words, the relevant subset links can be understood

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as being weak. In contrast, the temporal or order structures that generally dominate this form of recall are considerably more effective. In support of the claim of subset links operating for List X, if an individual thoroughly overlearns a list of say 20 items and is then asked whether certain foils or certain real targets were on the list (was “owl” on the list?), it emerges that an answer can be given instantly. In other words, the learner does not have to run down the 20-word sequence to discover whether “owl” was present or not. In this case, subset links appear to have grown strong enough to operate directly.

The issue of subset links will be pursued again in later chapters. One of the central arguments involves the hypothesis that such links operate across all bodies of memory content. For instance, if I meet a neighbor in a coffee shop and learn that his dog is called Zeus, I will not have to access the memory of the coffee shop in order to recall the dog’s name. Although this might appear an uncontroversial assumption, it emerges that it is in fact highly controversial. One major tradition urges that the dog’s name is lodged in the coffee shop memory and never becomes directly assimilated into my concept of a large black-coated animal first seen in a garden. The issue is examined in Chapter 7.

CHAPTER

4

Constructivism Under one view of memory, our recollection of a given event is understood as a copy of what had been seen and heard (or touched or tasted, etc.) during the event. The copy is weaker than the original experience—less vivid—but if you saw a silver kettle on a stove, the corresponding memory would be a representation of that silver image (and of course the image of the stove). This is of course the traditional empiricist view.

ORIGINS OF CONSTRUCTIVISM In the early twentieth century, two prominent authors introduced an alternative approach: constructivism. Constructivism derived from Kantian tenets, and as such was on something of a mild collision course with certain then long-established ideas within mainstream psychology. It was at first vigorously opposed (Alba & Hasher 1983; Bekerian & Bowers, 1983; McCloskey & Zaragoza, 1985; Zaragoza, McCloskey, & Jamis, 1987). Today, however, many researchers in the field of memory identify themselves as constructivists. Even so, this form of the theory is generally different in some ways from the original: it seems to have blended with the older, copier, tradition and undergone a shift toward empiricist tenets.

Constructivism in Psychology The two researchers who introduced constructivism into modern psychology were Sir Frederick Bartlett, widely read in mainstream memory research, and Jean Piaget. Piaget does not appear to have been absorbed much into the mainstream, if at all. It was Piaget, however, who wrote that, while he agreed with all of Bartlett’s theoretical positions, he was taking the approach a little further. At any rate, I shall call the basic position endorsed by both men, but including Piaget’s one step further, as hard-line constructivism, and the recent less Kantian views as simply constructivism.

A basic definition of the meaning implied by constructivism involves the following: when we live through an event, what we see and hear is interpreted, or constructed, by us. As Bartlett described the idea, we form an Human Memory, http://dx.doi.org/10.1016/B978-0-12-408087-4.00004-9

© 2014 Elsevier Inc. All rights reserved.

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understanding of the event, and the understanding, as well as the images immediately seen and heard, is the content entered into memory.To understand the event, we draw on information already present in long-term store: the relevant background knowledge. At the time when the memory is recalled, the system is again in contact with relevant long-term memory (LTM) knowledge, and the content of the memory is generated or constructed again, a process widely known as reconstruction. The same functions occur when we enter other forms of content into memory; for instance, when we read a book or watch a film.

Reconstruction Processes Our memory of Event X therefore consists of our understanding of the event, when we lived through it, and the images experienced at the time.

Also, it is possible that when we draw on knowledge in LTM to form this understanding, we draw on all relevant knowledge. Such knowledge can be extensive. So, when a memory is formed, the system makes contact with a great complex of data stored in LTM—not at all a camera-like function. And at the time of attempted recall, contact is again made with this vast complex.

FROM EMPIRICISM TO CONSTRUCTIVISM: EXAMINING THE EARLY PATH OF MEMORY RESEARCH Bartlett had been trained in the model that dominated experimental psychology across the first decades of the twentieth century. This reflected the original Lockean view that ideas and therefore the content of memories consisted of (sensory) units, put together to form images. This function was seen as additive: if several of the elements or units were joined, the result would be an addition of their parts—the sum of their parts. Critical to this view, more complex material did not imply emergent properties. If the principles that guided memory of the single units were understood, then these same principles would apply equally to higher-order content. This view directly informed Hermann Ebbinghaus’s seminal work with nonsense syllables and also research into human recall of lists (or other organizations) of random words, that emerged across the 1920s and has continued—although presumably without the same theoretical underpinning—to the present day.

Hard-Line Empiricism Thus, the men who pioneered experimental work in the field of memory followed an explicitly, hard-line, empiricist model. This directed the form

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of the research. The form became established and continued across the decades until the use of random words seemed as natural and correct— hardly needing examination—as the presence of trees in a forest, even to researchers who might not support the original theory. Had Kantian constructivism been the dominant model among experimental psychologists in the nineteenth century, it is a likely that the path of research across 100 years would have been quite a bit different.

Bartlett at any rate rejected the view that verbal units can be seen as an appropriate material for the study of memory.

Barlett’s Emphasis on Associations His reasons were twofold. First, nonsense syllables and later words had been chosen for research in part because they were believed to involve “pure” units of memory, i.e. uncontaminated by other material. But they don’t. If I see the item WOL, I think of WOOL, or perhaps “Without Official Leave,” and QWE instantly reminds me of Queequeg, from Moby Dick. The (Bartlettian) claim here is that all constituents in memory are associated with other constituents. In short, it is the fundamental nature of human recall that associations move autonomously from one body of content to another. Also, emerging properties do come into play as the memory function moves from random units to material with higher-order meaning. Under this view, powerful variables operate in the latter that are not present in the former.

One of these variables was the store of background knowledge described above. This background provides the critical information used when we live through an event and form an understanding of the event, or read a prose passage, and so on. However, given that our cognition is interpreting the relevant input, the possibility exists that on some occasions the interpretation may be incorrect. This is particularly the case given that the memory function appears to use inferential—reasonable or logical—processes to fill in gaps (weaknesses) in the original memory codes. Plausibility, it seems, is not always enough.

LONG-TERM MEMORY CODES It was stated earlier that under the traditional empiricist view of memory, our recollection of an event, such as seeing a kettle on a stove, involves a copy of the images perceived at the time. Here, the coded information would represent a silver metallic object of a certain size and shape,

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including two extrusions, one above the object although visually connected to it and one leading outward in a curved line. The early assumptions were that this visual image is connected in memory with words, such as “kettle,” that would provide its meaning. (In the 1950s, meaning was often understood as a network of word associations.)

Perceptual Versus Semantic Codes An alternative position here goes as far back as Aristotle, continuing through Kant to later classic-Aristotelian theorists and also to modern hard-line constructivists. It is the view that there exist two fundamentally different kinds of information in human concepts (Bruner & Postman, 1948; Piaget, 1951; Putnam, 1975a): one is sensory or perceptual, while the other centers on semantic codes that provide the stimulus with meaning. In the present example, if I see a kettle on a stove, I will identify the nature of the stimulus. Under this tradition, such identification involves an understanding of abstract kettle capacities. For instance, I will know that I am seeing something designed to hold liquid and withstand heat, such that the liquid can be boiled in it.

This latter information has been constructed from knowledge stored in LTM. It is not present or given directly in the image of the kettle itself.

Thus, from the beginning our understanding of the world (and so the codes of later memories) shifts beyond sensory experience.Yet the result is accurate knowledge. The object in front of me really is a thing designed to boil water, no less than a convex and shiny thing.

Coding for Functional Information Given these tenets, a typical recent memory consists of images, such as the image of a kettle on a stove, but also of abstract information concerning the nature of the object. Within the present tradition, the abstract content is the primary—most important—code relevant to understanding the event as such, and also the most important code for memory. This is the case because a bedrock constituent of meaning codes involves information specifying what the entity can do, i.e. its possible actions, including interactions with other things.This makes the meaning codes particularly adaptive; it matters more that we know what to do with a kettle than that the kettle is silver and shiny. This affects how we think about such objects, and, under the present view, the memory function is also structured to generate and retain the most important (functional) information.

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As we move about in the world, the construction (understanding) of what is happening around us (or other forms of material) occurs at ever higher or more generalized levels. Suppose I attend an outdoor wedding.

I will not only identify the stimuli that I see or hear, as in the example of the kettle above, but I will be aware that this is a ceremony in which two people express a commitment geared toward spending their life together. I will understand that this is a historically religious ceremony that may now be on a civil basis, and also the implications of the vows being made (in terms of a shared home, expected relationships, possibly children, etc.), and also why food is present, why guests are present, and why there are women in special dresses. All of this largely abstract information (and much more) is generated from background knowledge. It moves well beyond images. But again—critically—it is accurate knowledge. If I did not grasp the meaning of what is happening around me in terms of a higher-order understanding of weddings, it would be reasonable to say that I didn’t understand the event at all.

In summary, there has been a long tradition that posits a direct copy of an experienced happening—a moving film of the relevant images—should be seen as a true, accurate memory, while further interpretation, provided by the individual’s cognition rather than by input from the world outside, should be seen as potentially less true. The present model claims the opposite: that understanding events at a higher-order level comes closer to the real nature of the event than could be achieved through noninterpreted imagery.

It might be argued that the definition of the actual, true, recollection should be restricted to the images experienced and their identification at the conceptual level. Perception appears to be highly constrained: for the most part, we see what is actually present and we are unlikely to identify a kettle as a frying pan. (There can be exceptions to this when it comes to the exact contours retained in memory, as noted by Shepard in 1990, but for practical purposes the claim seems reasonable.) Perhaps it could then be argued that inaccuracies would only emerge when higher-level constructions come into play.

But this argument does not work either. It would confine my memory of a wedding to a kind of list of identified objects: tables with plates and glasses, a cake, perhaps various guests, and so on. Imagine how impoverished our mental world would be if we recalled a wedding as “many shining plates, many glasses, many men and women, several yellow dresses, sky,” etc.

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Memory Errors Due to Reconstruction It is true that the work of construction can lead to error. If I see a large dog leap at a man who then screams, I will probably interpret this as an attack. My understanding now is that I have seen an attack, and that datum will be present in the subsequent memory. As always, though, the reality of “attack” was not part of the images I saw—it was not defined or embodied in them. And the idea could be inaccurate. Perhaps I have unknowingly walked into an episode of boisterous play, such that my anxiety turns a wild shout into a scream. The incorrect element will nonetheless be part of the fabric of the memory, and not something added to it or associated with it.

The information that we construct, under the present view, is as much part of the memory itself as anything directly seen or heard. This is doubly the case since almost all of memory content is, in the end, interpreted content.

Errors are more likely to occur at the time of reconstruction than at the time of the first construction. This is the case, in particular, due to the capacity (and tendency) of the memory function to fill in gaps in the original codes on the basis of inference. This is normally a positive function, as will be illustrated below: but it does carry risk. Perhaps a year after that wedding, which took place in a garden, I recall the bride and groom standing on green grass, in front of a kind of bower. But they may in fact have been standing on an area of paved stone. If this datum has been weakly coded in my memory, the fact that it was an outdoor wedding, in a garden, with many areas of grass present, could have led the memory function to infer the nature of that area, too, as consisting of grass. It would be a quite rational inference; but it would be wrong.

EPISODIC RECALL AND MEMORY RECONSTRUCTION: SEPARATING THE TRUE EXPERIENCE FROM DISTORTION It was mentioned earlier that many constructivists today support a softer version of the model than the approach endorsed here. This seems to be due to a kind of shift back toward empiricist tenets. For instance, the following is widely posited. Certain events may occur, and these are experienced and coded during the relevant episode. This involves generally accurate information: the true recollection. But our episodic memory taps into the long-term store at the time of recall, and often at that time retrieves inferred, inaccurate content.

Under this view, there is the experience itself, which reflects the codes for what was seen and heard during the relevant episode, is copied almost

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directly from the world and is therefore accurate; then, there is possible distortion supplied by the reconstructive process. Suppose I am thinking back to a visit to the Smiths, and recall a large oak tree just outside their door. But in fact the tree had been an elm. The memory for the appearance of the tree is weak: all I have strongly coded is the fact that it was large.The memory function infers an oak, and enters this inference into the memory. There is the original, so to speak good, experience itself, and then distortion provided by invalid reconstruction.The following is a quote from Hirt, McDonald, and Markman (1998, p. 62) that effectively summarizes this position: “Although people would like to believe that their memories are veridical, the dominant view emerging from the psychological literature emphasizes the constructivist nature of memory. . . (Bartlett’s) work emphasized the theory-driven nature of memory and the biasing effect that schemas and expectancies have on what information is retrieved.”

The background knowledge (schemas) used in reconstruction are seen here as having a biasing effect. Thus, for many constructivists today the main issue that emerges from the constructivist view is that memory is vulnerable to distortion.

The Value of Schemas This differs from the hard-line theory of both Bartlett and Piaget in two critical respects. First, as discussed above, without the interpretation of episodes (or other material) that is provided by our cognition, human memories would be primitive indeed. Under this view, the work of reconstruction is the same function as the work of original construction; and just as necessary for coherence. The point of the model is that our interpretive capacities supply an understanding of the world that moves far beyond images; indeed, it may be one of the most complex—and useful—“things” under the sun.

The second difference here between the original and softer views of constructivism involves yet another function supplied by schemas. Under both Bartlettian and Piagetian theory, schemas supply memory strength.

This function will be examined in more detail later; however, the essential claim is that when information is constructed by (appropriate) schemas, that information will be better retained than would be the case had no schemas been in operation. Bartlett emphasized higher-order schemas in this role; Piaget emphasized schemas at every level; but the tenet of memory strengthening was the same for both authors.

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There is a corollary to this claim, though. For a schema to supply memory support, it needs to be the “correct” schema, i.e. it needs to be appropriate to the event. If for some reason (possible a clever experimenter’s manipulation) the applied interpretive structure does not fit the material, the input cannot be appropriately assimilated to the structure. Further, a situation such as this can precisely lead to a high level of inferential reconstruction, with the wrong bias. In short, the wrong higher-order (or other) schema will provide bias; the appropriate schema will supply—in some cases very strong—support.

We return now to the issue of the posited reality of the experience itself.

This is the old ideal of our simply registering events as a pure copy of what happened during an event—without interpretation. Under hard-line constructivism, things don’t work that way.We could not receive a veridical copy of the world at all if we did not deploy the capacity to interpret what we are seeing and hearing, even at a perceptual level.That is, we infer not only in terms of conceptual (and higher) meaning, but even in the case of received visual input—and would function less competently if we did not infer.

The issue of perceptual inference is described below.

Reconstruction Through Perceptual Inference Suppose I see an apple tree. The apples are present but largely obscured by leaves. I catch a glimpse of a few rounded, glossy red edges: nothing more.

I then understand that I am seeing apples, and form a memory of seeing apples. But I could not have generated this accurate information if I had not drawn on knowledge stored in LTM: that these things grow on exactly this type of tree, and what they look like, such that even the glimpse of a small part of the apple is enough for the viewer to know what it is. In short, without such knowledge, I could not have identified the reddish round half-contours that I actually saw. Here there is no autonomous experience itself, in which the world presented the clear image of an apple. The world didn’t: it just showed a hint that I was able to construct correctly based on my store of background knowledge. Under the present view, perception routinely works like that (Piaget & Inhelder, 1973).

There is an important corollary of the point made above, which relates perceptual experience to memory. There are two ways in which we might remember an object that we have seen. Suppose the object is again an apple tree. The first possibility is that we do copy into store an image of the outline, size, shape, colors, and so on, of the tree, basically as a camera would.

Later, if the code is strong enough, we may recall that image.

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The alternative view is this. When we encounter the tree, we code into memory some rough information concerning it—size, and perhaps general shape and color. But we do not memorize the image as such. Perhaps we were in a garden and saw the tree for a brief time; we walked past it, and saw it again on the way back. Strong as human recall is, we could not in that time encode the whole image—as a camera could. But we don’t need to because the appearance of this kind of object is already known.We know that there will be a trunk emerging from the ground, branches stretching from the top portions of the trunk, etc. Most of the image can be reconstructed at the time of attempted recall. If this were not the case, we would have a very hard time trying to remember what the garden or the trees or the walls or the house looked like. This, at least, is the insight offered by Piaget (Piaget, 1977; Piaget & Inhelder, 1973).

This influence of theory could hardly be described as bias. We reconstruct an image based on what trees in fact do look like. This goes beyond what could be memorized, as it were, from scratch as we walk past a tree.

If we are presented with pictures of unfamiliar things and later asked to recall them from memory, we do a very bad job of recollection. In contrast, a familiar thing may be recalled quite well. Figure 4.1 shows four pictures, two of a novel, unknown stimulus and two of a familiar stimulus, with images of each drawn from memory only 20 seconds after the pictures had been presented. The material has been taken from a classroom demonstration, with the pictures shown here being typical examples of the outcome.

Piaget’s View According to the Piagetian model, what occurs in the case of familiar memory images is a mixture of original “copied” contours and information provided by the relevant perceptual schema in LTM. For instance, perhaps we have briefly seen an image of a horse whose back is unusually long.This length is atypical, and so will not be inferred from a horse schema, but the length may be retained as a direct visual copy of what was seen. This kind of recall was called figural information by Piaget. It is completely noninterpreted. Schema knowledge will routinely provide other content, with the resulting memory image being a mixture of both figural and constructed information.

Research across the past several decades has supported this general view: memory images typically show some form of exact, noninferable, correspondence to the original, but at the same time are not like photographs, i.e. the memory omits many exact details of the original stimulus and,

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A

B

C

D

Figure 4.1  Memory drawings of familiar and unfamiliar images.  In each set of images, the top left-hand image is the original and the top right-hand image is a copy drawing made when the image was physically present. Images in the lower row of each set were made from memory after a 20-second delay. Panels A and B represent familiar images, and panels C and D represent unfamiliar images. While memory for images tends to be less accurate overall than copy drawings, memory for unfamiliar images, even after a brief retention interval, tends to be markedly less accurate than memory for familiar images. Undergraduate students at SUNY-Oneonta provided the memory drawings.

critically, tends to reflect its known (schema-derived) perceptual characteristics (Carmichael, Hogan, & Walter, 1932; Kosslyn, 1994, 2005; Kosslyn, Thompson, Sukel, & Alpert, 2005; Nickerson & Adams, 1979).

Thus, it is the claim of hard-line constructivism that visual memory works routinely to encode some original aspects of a stimulus, and to supplement this information with knowledge derived from perceptual schemas.

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A point of interest concerns relational information, which in fact is often poorly retained between stimuli, or between a visual object and the frame around it. This content is of course not coded in the schema. I know what a car looks like, but whether, in a specific episode, the car’s nose is pointing to my right or my left is no part of this background knowledge.

A final point centers on the issue of memory strength. The description above focused on inferred content, which is generated routinely to interpret what we see as we walk about in the world. The present model, though, makes a second claim, as mentioned above. If a memory image has been constructed by a perceptual schema (i.e. it concerns an entity whose appearance is familiar to us), then the image will be coded more strongly in and of itself than would have been the case in the absence of schematic support. It will be better retained. (Of course, the same is true of abstract content.) This reflects a position that is fundamental to both Bartlettian and Piagetian theory, but has not been widely accepted in the mainstream.

An Important Exception Under the present view, ( luckily) we humans are not cameras. The exception to this general view may be the people with savant syndrome, once known as idiot savants. In certain areas these men and women can recall stimuli in a literally camera-like or tape-recorder-like fashion. For instance, a book may be read once and repeated back verbatim. But the individual does not understand the content of those thousands of words (Treffert, 1988). Abstract thinking is barely present. It seems we cannot have both— at least not at a high degree of competence, or without severe cost. Given these facts, it appears that the absence of an exact, film-like capacity to record what we see and hear is a good thing.

An Empiricist Memory System: What is Experienced?

Some years ago I read the scientist-writer Gregory Benford’s (1987) terrifying novel, Great Sky River, which described living machine-derived creatures, mantises. At one point, the story moves inside the mind of one of the creatures.This is characterized as the sensorium of the mantis. Benford’s view of the mind appears to be empiricist: the creature’s awareness is a sensorium, filled presumably with shapes and colors—the green rounded contours of the grassy hill on which it stands, the blue above, and so on.

For myself, though, when I stand on a hill, much as I enjoy the stretch of green, I don’t think of my surroundings as “a stretch of green”: I think of them as a hill.

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THE NATURE OF HIGHER-ORDER SCHEMAS It has been noted that when human recollection works perfectly, you learn nothing about memory. There was a stone wall and you remember a stone wall. But if there was a stone wall and you remember a wheelbarrow—now you have a clue as to how memory operates.

Bartlett used this fact as the basis for some of his most important research. As he viewed human recall, the higher-order interpretations that we generate when we live through an event, or read prose (“This is a wedding”), operate to strengthen the subsumed memory content. But what if for some reason the wrong higher-order interpretation is constructed?

Schema Representation and Consciousness Constructivists write about schemas. The term originated with Kant, where it was used to describe the function that connects incoming perceptual experience with abstract interpretive capacity. Bartlett’s use of the word was somewhat different: in his work, as in Piaget’s, schema implies the capacity for interpretation itself, which could range from motor organization to the level of concepts, both concrete and abstract. Thus a table schema would be a body of information coding for the appearance and nature of tables, while a higher-order schema could be the information implied by the term “wedding” or “adventure story.” Under a hard constructivist view, schemas involve functions that are inherently nonconscious: they can be represented in awareness, but cannot themselves enter awareness.

Thus, Bartlett posited that a critical aspect of our capacity to understand and recall involves the automatic generation of higher-order schemas that enable us to interpret an event, or other material. Schemas were also seen as supplying critical strength to memory content. But what if an inappropriate higher-order structure were activated?

It should be noted that in daily life the higher-order schemas that we generate just about invariably do match the material we code into LTM. If I think I am at a wedding, it is a fair bet to say that I really am at a wedding. If I think I’m riding on a train—I am riding on a train. The same is generally true for prose content, films seen, and so on. In the case of prose, though, it is possible to mislead the reader and have the wrong higher-order schemas be activated. This was Bartlett’s strategy.

As noted above, under the constructivist view, the primary code entered into LTM as we live through an episode, or read a story, reflects our understanding of the episode or the story. A second critical tenet, adopted within

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the present tradition (and sometimes rejected by researchers with more of an empiricist/copier orientation) is that human semantic memory is largely based on a hierarchical structure.

The hierarchy is believed to operate for both episodic and conceptual content. In the case of events, there is the generation of lower-level content that is subsumed under higher, more generalized, and more abstract, content. Thus, the higher-order schemas mentioned above are part of the fundamental organization of human memory. If I watch a canoe regatta, the individual stimuli—boats, people, river, etc.—will be subsumed under something like, “A canoe regatta.” If I go on a vacation to Seville, the events will be subsumed under “Vacation in Seville.” In fact, there are likely to be many higher-order descriptions for any single episode. This basic view has been supported by a wide range of current research in the field of autobiographical memory (Burt, 2008; Burt, Kemp, & Conway, 2008; Conway, 2005; Conway & Pleydell-Pearce, 2000; Linton, 1975, 1979; Neisser, 1986; Newtson, 1976; Piaget, 1977; Schank, 1982; Schank & Abelson, 1977; Wagoner, 2008).

Under the constructivist model, the generalized descriptions—the higher-order schemas—are thrown up automatically. We do not have to deploy strategies to effect this (as is the case, for instance, when we learn random words and must deploy a strategy such as rehearsal). And they provide several functions, as described above. First, they enable the work of construction and reconstruction. If I understand that I am watching a regatta, I will be able to establish an entire model of what is currently happening and what is likely to happen—drawn from background knowledge.

They also provide the capacity for inference.

As noted above, the third major claim, within the present tradition and some others, is that when the details of an event (or prose passage) do fit the generated higher-order schemas, this will provide an increase in memory strength for those details (Bartlett, 1932; Bransford & Johnson, 1972; Piaget, 1977; Schank, 1982). (Lower-level schemas also provide memory strength, although the effect is not as great.)

Schemas and Coherence The opposite is also true. If some details don’t fit the higher-order structures brought into play, those details will be poorly retained. The same is true if no higher-order structures exist, as in the case of random words. This leads to a third aspect of the model. Bartlett noted that we have a strong drive to make sense of events, or other material encountered. Under the present view, if the details of an episode do fit the higher-order schemas that have

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been generated, then the episode will be experienced as coherent; it will be viewed as making sense. And of course events are almost always coherent in daily life—in the world out there. If I see money exchanged in a store, this fits my store schema. When I pour a cup of tea, the liquid flows down into the cup: it does not abruptly make a linear stream toward the window.The liquid flowing down in correct fashion fits my knowledge of physical motions in the world. According to Bartlett, our memory function has evolved in such a way as to take advantage of this kind of (both physical and social) predictability. If, however, the details do not seem to fit the higher-order interpretation, then our human drive to make sense of things can lead to an extreme use of inference; in the effort to reinterpret and so provide the missing coherence.

Prose material can be easily altered such that it no longer fits our schemas (“Yesterday my kitchen chair got sick and refused to eat”). And a less dramatic misfit can be provided by cultural differences. It was this second approach that Bartlett pursued in the attempt to lead his subjects to generate the wrong higher-order schemas when reading a brief story. Two outcomes could be predicted under Bartlett’s model: when the details did not fit the higher-order schema, those same details should be poorly recalled; and the drive to make sense of the material (as we are oriented to make sense of the world in general) could lead to an increase in distortion. In the latter case, the distortion would be due to incorrect inferences coming into play in the attempt to impose coherence on the story.

Bartlett wrote that higher-order schemas are like doors (Bartlett, 1932, chap. 3). If you walk through one, there will be a certain body of information available; if you walk through a different door, the information will also be different. Each leads to its own landscape. And the wrong door could provide a quite bad outcome in terms of memory.

A further prediction made by Bartlett was that weaknesses or gaps in memory will in some cases be filled, at the time of recall, by inference.

Critically, the inference would often work at an unconscious level, such that the inferred material would appear to be part of the original memory. (Of course, only inaccurate content could be distinguished from the original; there should be extensive accurate inference as well.)

Bartlett’s War of the Ghosts Study To research these various claims, Bartlett used a translation of an American Indian folk tale, The War of the Ghosts. It is probably one of the most famous passages in the field of memory. His subjects assumed that this was a realistic adventure story (the higher-order schema). But it wasn’t. It was

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a tale involving the supernatural (the correct higher-order schema). About two-thirds of the way through there is a battle scene that, for mainstream American or European readers assuming an adventure story, does not make sense. There is a lack of causal events where there should have been a causal event: a series of inexplicable facts is simply reported. And, as predicted, Bartlett’s subjects showed both weaker recall for this passage than for the rest of the story, and also, on the part of some individuals, an increase in distorted recollection, based on inference. One subject, for instance, incorrectly remembered the enemies in the battle as members of the Ghost Clan.

Bartlett later tested some of his original participants for their memory of the story across time, and found further forgetting of the battle scene, and also an increase in distortion.

There have been claims in the literature that Bartlett’s data had failed to be replicated in the modern era. On reading the claims, I was puzzled, since I had used this same material in classroom demonstrations, very casually, and replicated his immediate-recall results with a degree of ease that was almost startling. I had done this on about 12 different occasions.

In the original story, two young American Indians go hunting on a foggy river. They hear war cries coming from the river, and hide behind a log. Bartlett reported that some of his 20 subjects incorrectly recalled them as hiding behind a tree or a boulder. The deployment of background knowledge is apparent here. The use of reasonable “thought” is also apparent. The subjects had remembered that this was wild Indian territory, that a hiding event had occurred, and that the protagonists were grown men.What might be present in such wild territory, beside a river, and what might be large enough to hide a man? Certainly a boulder or a tree would qualify.

In my classroom demonstrations, on every occasion except one a couple of people recalled the Indians hiding behind a tree or a boulder—exactly as had occurred with Bartlett’s subjects (others either recalled the log, or failed to remember that the young men had attempted to hide). In the same way, the original story mentioned hunting seals, and some of Bartlett’s subjects remembered the men as going fishing. In almost every session, a few of my students also remembered the men fishing rather than sealing. The replication was surprisingly exact.

My students also showed significantly poorer recall for the (incoherent) battle scene than for the rest of the story. In contrast, their recollection of the material other than the battle scene was often remarkably good. I had read the story only once, followed by a (lecture-filled) delay of 12 minutes.

Bartlett had presented his story twice, with a delay of 15 minutes. I had no

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average recall scores from Bartlett (who did not report them), but my sense was that my undergraduates had performed better than his undergraduates.

Of course, this idea could have involved bias.

Nonreplication of Bartlett’s Findings Why then were there claims of nonreplication, when it appeared that replication was so easy? The studies claiming that Bartlett’s data were not accurate had focused on a different aspect of his work: repeated attempts to recall the story across time. But the researchers claiming nonreplication had not used either the original War of the Ghosts story, or material that was likely to cause their participants to generate an incorrect higher-order interpretation of the target information. It is in this way that the idea of “replication” can be seriously misleading.

The materials used ranged from pictured objects, to ordinary story content, to memory for a real episodic event (Gauld & Stephenson, 1967; Wynn & Logie, 1998; Zangwill, 1972). Again, none of this involved the likely generation of an incorrect higher-order schema; nor was the material designed in other ways to promote distortion. And, interestingly, none showed an increase in distortion across time, with repeated testing. All of this occurred, although Mandler and Johnson (1977) did at least note that the Bartlett material was not representative of typical prose!

Bergman and Roediger (1999), aware of the difficulties involved in trying to replicate the War of the Ghosts data with nonmisleading content, conducted a study in which they did use Bartlett’s original material.They also replicated his experimental conditions, so far as it was possible to do this (Bartlett had been vague concerning his exact procedures). They found increasing distortion as the memory was repeatedly tested across long stretches of time. In fact, the level of distortion was high. But they felt that they had not really provided a replication of Bartlett’s study, because they could not be sure that they had exactly copied his procedures (e.g. time intervals).

As a result, the phantom of nonreplication of Bartlett’s data appears to be still haunting the literature.

Repeated Testing and Memory Accuracy: Some Contradictory Findings Research into the effects of repeated testing has thrown up a complex pattern of findings. As described above, in the case of standard materials (not designed to produce problems with interpretation), repeated tests across

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time do not show an increase in distortion. In the case of misleading or confusing content, such as The War of the Ghosts, where distortion is often present from the beginning, it appears that this property may increase with repeated testing across extended periods, that is, with long delays between the tests (Wheeler & Roediger, 1992).

In marked contrast, some conditions of repeated testing lead to improvement in memory. This occurs when the material is tested either immediately or very soon after learning, and repeated tests are given across short periods of time. Although the material has not been presented again, recall improves. The effect operates for random words, but even more strikingly for images and for poems (Ammons & Irion, 1954; Ballard, 1913; Erdelyi & Becker, 1974; Haber & Erdelyi, 1967; Karpicke & Roediger, 2008; Roediger & Payne, 1982; Roediger & Thorpe, 1978). It is known as hypermnesia.

Reminiscence Prior to the discovery of hypermnesia, researchers had found that when more than one test is given for a list of words, some items that had been forgotten on Test 1 are recalled on Test 2. This phenomenon was identified as reminiscence. Generally, though, some previously recalled items were forgotten on Test 2, so the recall score was not necessarily improved.

Reminiscence is also a common outcome in episodic memories, as will be shown in Chapter 5. In contrast to reminiscence, though, hypermnesia involves an overall increase in the information recalled.

It is also the case that with autobiographical material, repeated efforts at recall frequently generate more and more recalled information. There can be marked hypermnesia. It holds true even for remote episodes.

Output Interference There is a phenomenon that leans in the opposite direction from hypermnesia. It does not involve repeated testing, but does involve ongoing testing from the same memory set. It appears within the context of the testing of random verbal items. As more and more items are recalled from a given set, it becomes harder to recall the remaining items. The effect is particularly apparent when the material involves exemplars of the same concept. For instance, if a target list involved many items of clothing, the recollection of a series of these items will produce impairment in the recollection of those that remain, as compared with a control condition. The effect is known as

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output interference, and obtains both in short-term memory and LTM, and in both recall and recognition (Battig & Montague, 1969; Criss, Malmberg, & Shiffrin, 2011; Malmberg, Criss, Gangwani, & Shiffrin, 2012; Raaijmakers & Shiffrin, 1981; Roediger & Schmidt, 1980; Slamecka, 1968, 1969; Smith, 1971). Data have also been provided in support of the view that the difficulty of recalling a large, as against a smaller, quantity of random items does not reflect the difficulty of holding the items in LTM, but rather on the act of retrieval (Dennis, Lee, & Kinnell, 2008).

Thus, there exists a complex web of outcomes related to repeated testing. In some cases, retrieval strengthens an entire body of content; in other cases, it has the opposite effect. The brief outline above probably suggests a difference in outcomes for material with higher-order content—material constructed by higher-order schemas—and material lacking higher-order content. But the divide involves more than just this property, since hypermnesia is also found in the case of random words. The issue will be examined again in Chapter 8.

Bartlett’s Methodological Approach Versus Modern Practices Bergman and Roediger (1999) noted that Bartlett’s methodological approach was quite different from current practice. He tended to describe aspects of his subjects’ recall that he found interesting (such as the inference of a boulder when the original had been a log), but did not always quantify how many subjects recalled the material inaccurately or accurately, and so on. Today it is a cast-iron convention to report all aspects of procedures and the average scores. In contrast, the content of the material is not normally described. A reader might learn how many participants distorted an element of their memories, but not the nature of the distortion itself.

The practice of not reporting content is completely entrenched today.

Yet, although I feel that I acquire important information when I am told how many participants recalled some given material incorrectly, I also believe that much can be learned when the reader is exposed to the recalled, inaccurate material itself. Discovering that people often remember a log as a boulder, although only within a specific context (a certain kind of territory), is surely informative.

Recently a small movement has begun that supports the idea of reporting individual memory content (Mori, 2008; Wagoner, 2008). There are dangers in this practice, since describing content generally involves interpreting that content (if the description is to be useful). But it is also the

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case that misinterpretation can be present in today’s standard methodologies, even though this is not generally acknowledged. An obvious example would be the widespread claim that attempts to replicate Bartlett had failed.

Wagoner noted that until World War II it had been standard to report content when researching memory. This of course involved a description of what single individuals recalled: it was not a composite score. The movement noted above advocates that both individual memory content and average scores should be reported, where appropriate. It seems a good idea.

CONCLUSIONS The present chapter introduced a hard-line constructivist approach to memory. Under this view, the traditional idea that humans can enter into LTM a “true,” i.e. wholly or largely noninterpreted, copy of an event (or other material) is rejected. Inferential processes are used to understand even the most basic perceptual input. We constantly see only edges or parts of things around us, but can often identify the nature of objects based on stored knowledge. Further, interpretive capacities come into play to make sense of experience at the conceptual level, from the concrete object to the most abstract. These provide a powerful and extensive capacity to understand the world. And perhaps the most critical point is that without such functions, our comprehension and memories would be extremely primitive. Also, most of this constructive work is accurate. Therefore, the belief that the point of schemas is that they provide distortion (through a kind of application of theory) cannot be supported.

It is true that the memory function may infer inaccurate content. This occurs mainly because this function takes some risks at the time of retrieval: it will infer a plausible element even though there is no guarantee that the element is correct. (In general, though, this kind of inference appears to operate most frequently for the trivial components of a recollection, such as the color of a dress; high-level information—for instance, the nature of an event in its entirety—appears not to be often misrecalled, under what might be considered standard conditions.) In conclusion, due to the work of inference, memory content can be inaccurate. Even so, the fundamental point of construction is that it provides the enormous power that exists in human understanding, and thus in human recall.

Meaningful information in memory is interpreted on the basis of schemas. In many domains, including episodic memory, these entities possess hierarchical structure. When a schema is used to provide the meaning of

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some body of input, the relevant content is strengthened. Higher-order schemas are particularly effective within this context. Schemas also provide our capacity to interpret the world, to infer, and to anticipate what is likely to happen next—in most situations.

As mentioned earlier, one of Bartlett’s claims was that material that elicits emotion leads to stronger-than-average memory codes. This position again implies the typical constructivist assumption that variables operating within our cognition (i.e. not derived from the world) can fundamentally alter memory. In The War of the Ghosts, there is a scene in which the beings in the canoes urge one of the seal-hunting young men to accompany them to a war. One of the young men makes three excuses not to go, in the following order: I have no arrows; my people do not know where I am; and I might get killed. Bartlett noted that all of his subjects who remembered the fact of excuses recalled the “I might get killed” constituent first. These were young men of military age at the time of the brutal World War I, when many of the officer class (to which these privileged individuals belonged) did not survive. In Bartlett’s view, the knowledge that they might die in the near future, and the emotion provoked by this knowledge, had influenced their recollection of the Indian story.

Again, Bartlett’s data here could have been the result of chance. And research into the effect of emotion on reordering memory content has not to my knowledge been pursued. In fact, the role of emotion in strengthening, or not strengthening, human recall has received surprisingly little attention across the past 100 years. When it comes to memory, we know something about the effects of emotional arousal in rats (there is a large effect), but little when it comes to men and women. Here is one area where Bartlett’s arguments have not been pursued, perhaps because of methodological difficulties, although the reasons for this lack of action remain unclear.

CHAPTER

5

A Personal Memory Across the past 24 years I have kept a journal of various holidays taken both in this country and abroad. I tested my memory for these trips across three different time intervals (for separate episodes). A second attempt at recall was made later, a decade or more after the original event.

In the present chapter, I describe a personal memory taken from these accounts. The object is to examine the content of an actual recollection. It involves a remote event (17 years in the past); as usual, the best light shed on human recall comes from an analysis of its errors.

It is assumed here that when an episodic memory is formed, a new complex of information is established in long-term memory (LTM). The nonperceptual (abstract) information in this complex is drawn from the relevant schemas; that is, if a boat is recalled, the present approach posits that a long-established boat schema was drawn on to provide the meaning of this constituent. It is not known at present exactly how this relationship functions. For instance, the meaning of “boat,” or some part of the meaning, might be copied into the new memory complex. Or some node or token may be created in LTM that involves “pointers” (associative relations) to the relevant schemas, along with information specifying how the elements in the memory interrelate. Various other possibilities exist.

With regard to changed memory content, two possible sources of change can be identified. The first involves a phenomenon in which correct mnemonic information is recalled, but is attributed to the wrong episode. This outcome has been described as source misattribution ( Johnson, Hashtroudi, & Lindsay, 1993; Johnson, Raye, Foley, & Foley, 1981), and also as a time-slice error (Brewer, 1999). Basically, the individual is trying to recall Memory A and retrieves (accurate) information from Memory B, mistaking it for a constituent of Memory A. Both empiricists and constructivists agree that errors of this type occur in human recall.

The second possible cause of changed memory involves what has been called inference. Here the memory function infers or deduces at a nonconscious level what some aspect of a body of content may have been, and inserts this material into the memory (Bransford, Barclay, & Franks, 1972; Glenberg, Meyer, & Lindem, 1987; Johnson-Laird, 1980; Rinck, Williams, Human Memory, http://dx.doi.org/10.1016/B978-0-12-408087-4.00005-0

© 2014 Elsevier Inc. All rights reserved.

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Bower, & Becker, 1996; Sulin & Dooling, 1974; Thorndyke, 1977; Zwaan, Radvansky, & Witten, 2002). This often involves simply constructing background information relevant to the memory, such that this information becomes part of the memory. It can also, however, involve the generation of inferred material at the time of recall. As will be discussed later, some perceptual information is also constructed in this manner. Critically, the inferred content, of any type, cannot be subjectively distinguished from the originally coded content. Constructivists, but not hard-line empiricists, also endorse this view.

A CRITICAL ANALYSIS OF A DISTANT PERSONAL MEMORY For the purpose of this chapter, I attempted to retrieve a memory in the present. It involved the final day of a trip to Morocco taken in 1994. It was chosen because the events of a first or of a final day tend to be distinctive.

Had I chosen, say, the fourth day of the vacation, I would not have been able to isolate the events of that particular period of time. As mentioned earlier, we are very weak at recalling episodic memories based on a temporal marker, such as “fourth day of the vacation” or “March 17” (Friedman, 1993).

This material (but including the entire trip) had been first recalled 4 years after the event, and recalled again 14 years after the event. The present demonstration involved recall after 17 years.

Methods Used in Evaluating the Accuracy of the Memory In recollection, I scored memories for my confidence in the relevant accuracy from 1 to 5, with 1 being the lowest score (think it is accurate, but not very sure) and 5 the highest (complete confidence).

A borderline memory is content that returns, but which you are not certain whether it is accurate or not, even at a very low level of confidence.

I report this kind of content followed by a question mark.

Imagery for the recalled material was scored 0–4, where images were relevant. Lower than 1 (e.g. 0.5) indicates something like the hint or idea of an image rather than an actual image; 1 = a kind of hazy sense of something visual or auditory being present, and a general feeling of imagery, but without the ability to see any detail; 2 = ability to see some detail; 3 = enough detail that I could draw the image from memory; and 4 = the same as 3, but with a sense of definite clarity.

My remote memories are generally characterized by the following kind of imagery. I have a sense of an entire scene, with shapes and colors that

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are appropriate to that scene; but it is more like a suggestion or a daub of imagery than actual, clear imagery. This kind of recall, which is characteristic of most broader scenes that I can remember, I score as a 1. I also tend to recall the quality of the light, if it is distinctive.

I have visited Morocco twice as an adult: once in 1994 and once in 2002. As will be seen, the fact of the two separate trips to the same country introduces particular issues centered on time-slice errors.

Cues can be expected to play a major role in this form of retrieval.

Following Anderson (1983b), it is assumed here that two major goals in the present case could be described as (1) I want to recall the first trip to Morocco; and (2) I want to recall the last day of that trip. It should be noted too that anything further that I might know or understand, or retrieve, about this target could also operate as a cue (Norman & Bobrow, 1979).

The Memory as Recalled in the Present (2011) No content appeared immediately. I knew that we must have left the country from an airport. I recalled then that we had both arrived at and left from the Casablanca Airport (4.8). (Note that my ability to recall did not center on the “last day” information directly. Time tags work very badly in my efforts at recall. Instead it centered on “What must have happened on the last day”).

I then recalled the airport. The actual memory is recorded below.

I see the surroundings fairly clearly (2.0). We were already inside (5.0). The place was large—large rooms—and there had been, I think, a very ornate high-ceilinged first room, and then another with stone, probably marble, floors (3.5). Or possibly both had marble floors. A man was mopping the floor (4.8). He was a lean, older man, wearing a djellaba (4.5). I was very happy to be there (5.0). I had lived for 6 months in Morocco as a child, and was really pleased to be back. There was a glimpse of the outside world through a window or windows (3.0). The view may have included palms (1.0). The windows were on the left-hand side of the long room (3.0). I recalled something awkward related to a visit to the ladies’ bathroom, but not what in particular caused the awkwardness (1.5).

Imagery: for airport physical properties such as size and floor, 2; for the man, 2; for windows, 0.5; for the scene through them, 0; for entrance to bathroom, 0.

At this point in my attempt at recall, I realized that the information I had just recalled, and written down, was wrong. I probably caught the error due

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to recalling the emotion component: “very happy to be back there again” was the thought and feeling. But that would be inappropriate for leaving the country. What I had done, I concluded, was to erroneously recall the airport scene of our arrival. As soon as I thought this, I was sure that I was right.

As we both arrived and left from Casablanca, I registered that I should be trying to remember how the airport looked when we left. I then recalled Casablanca Airport on the day of departure.

I remember the inside of the place (3). It looks different from the scene of our arrival: no huge rooms and marble floors. The building seems to involve a long corridor-like area, maybe a T-shape architecture, with shops (2.0).

Imagery for the scene: 1.

But that would not have been the start of the day. Of the earlier hours, I got nothing that was clear, although I spent some time generating cues and searching. What hotel? What breakfast? What did the airport look like from outside, when we entered?

In this effort, some ideas so vague that I thought, as I wrote them, were probably unreal—false memories—came back.

There was an image of a dining room that had a raised and a lower area, with a cash register near the door? In our hotel. It was not at all fancy or impressive? And our room at a hotel just suggested itself—a wall there? (a spatial sense of it in relation to the bed and the window), a window, a city scene outside?

Imagery: 0.5.

For a while I could get nothing else. Then something did return, quite suddenly.

The taxi driver! He was young and very friendly (4.0), in western dress (1.0).

I think he was tallish (1.0). And he was definitely someone we met on the day of departure (4.5). I think we found him when we were looking in a crowded place—there was a pavement, a broad pavement or space, a crowd, taxis (1.0).

Imagery: for the driver and for the pavement, 0.5.

He talked cheerfully as he drove us to the airport (4.8). He talked about Morocco, asking us how we liked it (2.5). He was married, to a Moroccan

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woman (4.8). He said that Moroccan women were very nice (4.8). He also said that my son might like to marry a Moroccan girl (4.8), and the comment startled me (4.8).

Imagery for this scene: 0.

The driver watched us when we got to the airport, to be sure that we were all right (3.0). He had gotten out of the car to do so (1.0).

Imagery: 0.

I remembered the airport again, with the same image of a corridor-like layout that I had recalled earlier. Next came a memory of going to a cafeteria, at the end of a passage (4.0), which seemed crowded (1.0) and there was something disappointing about it (0.5). I think we drank chocolate? Later, there may have been some kind of complication—about which desk to go to sign in? (1.5). This was hazy and I think possibly belongs to another memory (e.g. Trip 2 instead of Trip 1). I recalled trying to talk to someone behind a desk, with communication problems (3.5 for the fact that this happened, and in Morocco, but 0 for it occurring on the departure day of Trip 1).

Imagery: airport scene: 1; everything else, 0.

Later, we went into one of the stores (4.5). In the store, I had selected a jumbo Crunchie bar for us to eat later (3.5). But at the counter they would not accept my dirhams, the Moroccan currency (4.8). Apparently they only accepted euros in the airport; they would not accept dollars either (3.5). So I had to leave the Crunchie bar behind. I recall thinking that it was very odd that dirhams would not be accepted in a Moroccan airport, dirhams being the currency of the country (4.0). I wondered if the airport was somehow international territory—which also seemed peculiar (4.0). But I again had some doubt as to whether this recollection was from my first or second trip to Morocco.

Imagery: a spatial sense in the store, 0.5.

A memory of buying a toiletry bag in an airport intruded, but I at once identified this as incorrect—from a different episode. I would give a certainty that this event occurred a 5, but I would give a ? to my ability to recall where it occurred.

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We boarded the plane with no difficulty (3.0). I recalled nothing at first of the flight or the landing.

I recalled being on a bus, going from the Port Authority to Oneonta, after a long trip. We were tired and trying to sleep. But there were some very noisy people on a seat at the back of the bus (4.8). However, there was no certainty that this was the bus trip home following Morocco Trip 1,and I would score this as a ? (A memory also intruded at this point concerning a bus ride from the airport into New York that I knew at once, from its content, derived from Trip 2, and rejected.)

A final idea concerning the holiday was this. On the plane, my son was carrying a drum that he had bought in Tangier: a blue and white drum (3). It had not been put in the luggage—too awkward (3.0). But, again, I could not determine whether this memory came from Trip 1 or Trip 2, and would therefore score all this content with a “?”.

As I looked back on this attempt, I felt that the episode in the Casablanca Airport store, with the Crunchie bar, might well be invalid. The only place in which I could remember ever buying Crunchies, apart from the present episode, was the UK. I suspected they were not sold outside of that country (or only in special “British goods” shops). And I could not recall a jumbo Crunchie anywhere. I wondered whether I had confused the airport entirely, with an airport in England. But the sense of place information (that it was at Casablanca) seemed quite strong. Also, if it had been an English airport, I would have offered English money, which would not have been rejected.

I then went back to my journals to check on the accuracy of the present content.

THE NATURE OF AUTOBIOGRAPHICAL MEMORY Before reporting the findings concerning this recollection, I would like to introduce some research concerning autobiographical memory.

It is widely accepted that our personal memories possess hierarchical structure. Further, different authors have reached similar conclusions concerning the nature of this structure. Toward the top of the hierarchy are “lifetime periods,” such as “the time I was married” or “the time I worked for Company X.” Beneath this come “episodes,” which involve particular events, such as a dinner party or going on a hike. Then in some models,

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such as Linton’s, there are “elements,” which are constituents of an event; for instance, the fact that on the hike one individual twisted his ankle, and all that occurred in that scene. Finally there are “details,” such as the appearance of a leaf, or the presence of a bowl of flowers on the dinner table (Barsalou, 1988; Brown, Shevell, & Rips, 1986; Conway, 1992; Conway & Bekerian, 1987; Linton, 1975, 1979, 1986; Neisser, 1986; Schooler & Hermann, 1992; Treadway, McCloskey, Gordon, & Cohen, 1992).

Linton’s Model of Autobiographical Memory Lintons’ model includes two yet higher constituents. At the top of the hierarchy is “mood tone.” This involves a certain feeling or mood concerning the material subsumed under it.You may recall that an event was somehow pleasant, even when you hardly recall anything about the event itself. (I have found the same thing with books read many years earlier.) A similar conclusion was explored by Bruhn (1990), reflecting the way people feel about certain memories. Linton also includes “themes” as her second highest level in the hierarchy.These would involve major issues in your life, such as the theme of work, love, friendship, relations with others, and so on. A simple representation of this kind of hierarchy is shown in Fig. 5.1.

As with conceptual structure, the lowest categories in this kind of organization participate in the nature of the directly superordinate categories.

For instance, seeing a leaf (a detail) could be part of an element when you walked up a tough path, which was part of the hiking episode, which was part of the lifetime period when you worked for Company X. Under the present view, all of this information is active in cognition as you form a memory of the hike or the leaf, and all constitute part of that memory. Also, particular recollections will not infrequently be subsumed under more than one higher-order component: the day of the hike may involve the time you lived in Pennsylvania (lifetime period), which overlaps with the time you worked for Company X, and may relate strongly to a friendship theme.

A critical point made by researchers in this area is that the highest levels of the hierarchy typically involve the content that is easiest to recall and that is often accessed first (Burgess & Shallice, 1996; Conway, 1996; Conway & Hague, 1999).These authors favor the view that complex retrieval strategies, related to goals other than the obvious goal of retrieving a target memory, are involved in the process. It reflects the view that human memory is essentially controlled and directed by the individual’s goals and, further, that these particular goals relate to the individual’s desires concerning his or

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Mood Tone

Themes

Extendures

Isolates

Amalgams

Events And Episodes

Elements

Details Figure 5.1 Linton’s hierarchy of autobiographical memory content. In Linton’s model of autobiographical memory, our personal memories are organized hierarchically with the emotional quality of the memory at the highest level (e.g. Mood Tone).

When we recall a personal memory, we typically access the highest levels of the hierarchy first before recalling the lower levels. Furthermore, there may be considerable overlap between the different levels of the hierarchy for a given memory. Isolates and amalgams are depicted outside of the main body of the hierarchy because they represent, respectively, events and episodes that are not logically related to the experiences of one’s life.Source: Linton (1986). Reprinted with permission of Cambridge University Press.

her self-image (Barsalou, 1988; Conway, 1992; Conway & Pleydell-Pearce, 2000; Markus & Nurius, 1986; McAdams, 1993; McAdams, Diamond, de St. Aubin, & Mansfield, 1997; Sheldon & Elliot, 1999; Singer, 1997; Singer & Salovey, 1993). Under this model, we construct ideas of how we wish to be, and the relevant ideas sometimes contrast with the way we are; or there could be memories suggesting this kind of “dissonance.” Here, the desired

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self-image is seen as controlling autobiographical retrieval; in some models, it operates literally as a control process.

This view is not endorsed in the present book. It is certainly the case that when a very important goal is achieved, the resulting memory is likely to be strong. But the position taken here is that the causal element is not the fact of goal achievement as such. We achieve or fail to achieve minor goals on a daily basis. This produces no particular emotion, and does not enhance memory. For instance, if I need groceries, I go to the store. In contrast, the achievement of a major goal related to the self-image is likely to induce strong emotion: this, not the goal achievement as such, is the critical factor.

The distinction might not be important, except that there are many variables other than events related to a self-image that produce strong emotion, and also interest, in the course of our lives: and these can all strongly enhance memory. Under the present view, then, the role of our personal self-image is not the bedrock on which autobiographical memory is founded.

The present book focuses to a greater extent on the fact that the higher levels are more strongly coded. Under this view, the strategies deployed are simply strategies intended to activate the target memory, usually without any other agenda. For instance, if a memory is somewhat recalcitrant, then a higher-level code is more capable of being activated by the cues, and thus a good means of finally retrieving the target. Once the higher element is activated, activity can then travel “down” through the hierarchical structure, perhaps leading to successful recall of the desired memory.

At any rate, it is a commonplace fact that you will recall that you worked for Company X after you no longer remember the hike, and will typically recall the hike as such when you no longer recall seeing a particular leaf.

A point of particular interest for the present book involves the fact that we can label these components of the hierarchy, and we use these labels communally. That is, if you tell me that you went shopping this afternoon, the “shopping” (episode) label will be perfectly coherent for me, and, critically, I will have a sense of where the relevant events began and where they ended. Thus, researchers into autobiographical memory have noted that we organize our personal memories into event units (or other forms of unit) and can identify “break points,” when one action or series of actions ended, and another began (Anderson & Conway, 1993; Brown et al., 1986; Conway & Pleydell-Pearce, 2000; Newtson, 1976). The same thing operates at a more detailed level: we can separate out, mentally, the individual components of an event, which can be thought about or conceptualized individually (Burt, Kemp, & Conway, 2001, 2003).

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We use language terms to represent each body of content, such as “the hike on Monday” or “the roses on the table.” But in the long-term store the relevant information must be represented in the form of concepts, rather than words. A claim is also being made here that this kind of function operates for concepts of things, as well as for events (going hiking) and percepts (the red roses). When you learn a list of words, the list becomes conceptualized in the same way as “that list I learned.”

Headers and Subset Links Throughout the present book I am calling these labeling constituents headers. It may be a clumsy term, but it seems to convey the essential idea. A header will subsume a body of information. Also, a claim made here is that there exist subset links between the header and the relevant subset material, i.e. that the forming of such links is something the memory system does automatically (without conscious intent). In addition, not only will the mini-events (the elements) experienced on a hike be organized in memory under something corresponding to, “That Hike on Saturday,” but so will any other information, perhaps acquired later, that is relevant to the episode. Perhaps you learned a week after the hike that the steep hill you climbed was the toughest in that county. When you recall the hike now, your memory will include that knowledge.

A further critical point is that a header is not something separate from the general body of memory content. It is not, for instance, like the title of a book. It is simply a cognitive representation that has other content subsumed under it, and exists at all levels of the hierarchy. As we move about in the world, we see various objects and people and immediately construct higher-order interpretations of the meaning of those things, up to the most general of all (Neisser, 1986). As I saw a man mopping a floor in Casablanca, I was aware at that and every subsequent moment that I was in an airport, that I was traveling, that this was a vacation, that this was a trip to Morocco, and indeed who I was, and so on. Headers would operate at all these levels, and any one of them has the potential to access the memory content subsumed under it.

Retrieval of an Episode My Casablanca memory was contacted by an episode header (the last day of Trip 1 to Morocco) and so the strategy of working from a moderately high component in the hierarchy came into play automatically. My task

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then was to recall the elements of that day (the various scenes and minievents that constituted this episode), and the details.

A second pattern of the function involving recall is to begin at the beginning of an episode and work through the episode sequentially (Linton, 1975). This is also an effective way of activating a memory. The links here are generally believed to be temporal links, and the forward order also allows causal relations, which generally involve strong links, to come into play as well (Anderson & Conway, 1993; Burt, Kemp, Grady, & Conway, 2000; Rubin, 1986). As suggested in Chapter 3, however, I believe it likely that both temporal and order processing structures are at work in personal (and also word list) memories.

The patterns of errors in ordered recall for verbal items have been solidly established (Bjork & Healy, 1974; Glanzer & Cunitz, 1966; Murdock, 1962; Nairne, 1991; Serra & Nairne, 2000). This involves the well-known serial position curve, in which items in the middle of a list show the highest level of error. The same pattern, that of increasing errors in the middle of a string of events, has been found in autobiographical recall for a series of photos of scenes encountered in a tourist-like situation (Burt, Kemp, & Conway, 2008). Thus, there is evidence supporting the view that the processing structures in play in both the ordered recall of verbal items and the ordered recall for life events are the same.

Most life events, though, are unlikely to show this tidy pattern. In the case of a series of photos of scenes encountered across a period of time, the scenes will probably not differ a great deal—perhaps a little—in terms of their interest to the participant, or in the patterns of interference operating across them. They are all much the same. Events in daily life, in contrast, are often not the same at all. Some stand out as of greater interest than others, and this variable is like a cannon roaring up to the front—interest will wholly override serial order when it comes to the probability of future recall. The same is true when it comes to interference. Some constituents of an episode may have a far greater potential for interference than other constituents, and thus show a poor level of recall even if they are positioned toward the beginning or end of an episode, as against in the middle. These properties were clearly in evidence in my recollection of Casablanca Airport, which, like the other journaled memories, showed none of the classic serial position effects (either for content memory or for order memory).

The following section covers the scoring component for that episode.

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Evaluating the Episode I had at first confused the airport scene of our arrival with the airport scene of our departure. This was a time-slice error involving different days of the same trip. The following cues and hierarchical organization appear to have been operating at the moment when the incorrect scene was retrieved.

Cues: Day of Arrival info

MOROCCAN TRIP 1, day of departure: remote time Casablanca Airport Day of Departure info

XXX (recalled)

It is assumed here, as with virtually all models of order recall, and models of word recall in general, that, at any given moment, the relevant constituents in LTM that are most highly activated are retrieved.

For some reason, in the present account the “day of arrival” became more highly activated than the “day of departure,” and was retrieved.

This was a fairly typical example of a time-slice error. Here, there is a header or headers of some kind that fit the incorrect information. The header in the present example would be: Moroccan Trip 1, Casablanca Airport.

To describe this in a somewhat different way, the present error was an example of a partial cue match. The full range of cues included “day of departure,” such that this complex (Moroccan Trip 1, Casablanca Airport, day of departure) would have overlapped more completely with the correct target, but it was the partial content match that prevailed. It is assumed here that “Morocco Trip 1, Casablanca Airport” was contacted by the cues and activation led from that point, within LTM, to the nontarget scene.

Tulving (1983, chap. 14) noted this phenomenon too, in word recall.

Sometimes a more complete match between cues and memory content is less effective than a partial match. He attributed this to the variable “quality” of the content being matched. I would be inclined to describe this as the strength of the memory, rather than its quality, but the basic idea is the same. I believe the greater strength of the memory (of the scene of arrival) in the present case derived from the fact that the arrival in Morocco was a moment of strong interest and even emotion for me.

The day of departure was not. Thus, a partial match body of content, with a strong internal strength factor (strong “quality”) can dominate and override a full match.

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In the present example, it might be argued that the day of departure was weakly coded, such that I lacked the ability to recall it. In short, the cues could not effectively find a complete match because the target memory was too fragile for a match to succeed. But this explanation is negated by the fact that once I realized I had made a mistake, I tried again, and this time recalled the correct day.

It is possible that if there had not been a clue in the content of the retrieved memory indicating that it was inaccurate, then I might have accepted it and not made the second attempt to recall my real target.

The present example again fails to support the view of a memory identification “tag” being read as a prerequisite for retrieval. It was the wrong memory and a tag (indicating “day of arrival”), if it was read, should have prevented an error of this kind. The function appears to be rather that of (some) cues contacting matching information and, if there is then a strong association from that point to nontarget material, the latter material may be activated to the point of retrieval. (This does not mean that “day of arrival” was not coded with this memory: it clearly was. The only claim, as stated above, is that the processing of this information was not part of the required events prior to its retrieval.)

Although the airport scene as first recalled was the wrong memory, it was nonetheless an example of episodic recall. I have therefore included an account of the degree of accuracy of this segment, as described below.

Dissociative Elements in Recall My recollection of the general appearance of the airport proved to be accurate, including the mention of windows to our left. However, there was no glimpse of palm trees outside the windows.This proved to be another timeslice error, relating to the day of our arrival. When we had first arrived, flying from Casablanca to Tangier, I caught a glimpse of palms through the window of the small airport in Tangier. Thus, this error involved both the wrong day and the wrong place, although again several elements of the higher-order information fitted the inaccurate content. The header here could be described as “airport in Morocco, airport window.”

A property that emerges very soon in autobiographical recall of this kind is the dissociative quality of our memories. Far from there being some kind of set piece, like an integrated picture, for any given episode, constituents that fit well with a given scene, say Scene X, may be quite reliably transported to Scene X. Thus, my memory did not hold all the elements of the Casablanca-arrival episode inside some kind of bounded

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file or set. Instead, a constituent that seemed to fit well with the airport scene at Casablanca (i.e. seeing palms through a window) was moved from its original context. This phenomenon occurred quite consistently across the journals. One of the striking features of the tendency was how well the transposed element tends to fit with its new frame.

I believe the glimpse of palms was coded with a high level of strength for the same reason as obtained for the Casablanca Airport arrival scene.

Palms were part of my childhood memories concerning the country.

Seeing even a glimpse of them again involved a strong subjective reaction.

I had recalled an old, lean Moroccan man mopping the airport floor.

My confidence level for this element had been high: 4.5. But the journal revealed the following. There had been a Moroccan man mopping the airport floor (and the floor was marble, as I had recalled); but the man had been young.

I had attempted to recall the present target day twice in the past. I checked back on these earlier recollections. In the 4-year recall, the individual was recalled correctly. In the 14-year recall, he was recalled simply as “a man.” Now I had transformed him into an old man. It seems unlikely that this error was due to source misattribution. For this, it would have been necessary for me to have seen an old Moroccan man mopping an airport floor at some other time. I am fairly sure that this never happened. Certainly, there was no such figure, noticed by me, at Casablanca Airport on the target day (as the journal revealed). But need we be that strict? Could a time-slice error involve an old Moroccan man mopping a floor—somewhere?

That might be good enough. So, have I ever seen an elderly individual of this kind mopping a floor? (Note that just an old Moroccan man, seen on another occasion, would not do: in my memory, he is active—he is pushing a mop. And a man really was pushing a mop in Casablanca Airport.) So time slice would require one elderly mop-pushing individual to be lifted from Memory A and slid into Memory B. I think the alternative view here is more likely. I had probably inferred an older man. I have seen many Moroccan workers, and most looked old.

They also showed the lean, dried-out appearance that I mistakenly attributed to the worker.

The other constituents of the airport scene were accurate, although there was a tendency toward generalization. In the present, I recalled feeling some awkwardness over my visit to the ladies room in the airport. But I didn’t know why. The journal revealed that there had been no machine provided at the entrance, to pay, and no visible attendant inside. But when

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I exited I found a young Moroccan girl standing at the door as if she were the attendant. I thought that probably I was supposed to pay her, and did so, but I wasn’t sure. Anyway, that was the awkwardness. In my present recall, all the elements and details had been forgotten, and only the high-level (generalized) single fact “I visited the ladies room” and the accompanying sense of feeling awkward remained. The tendency toward generalization—moving up to a relatively high, summary description of the event—as memory weakens, has been identified both in prose recall and in episodic recall (Brewer & Dupree, 1983; Cohen, 2000; Kintsch, Welsch, Schmalhofer, & Zimny, 1990). This of course fits with the claim that higher-order content is in general more strongly coded than lower-order content.

I tend to believe that the only reason I recalled that scene with the young attendant was because of the emotion it generated: the awkwardness (support for Linton’s view of the enduring power of “mood tone.”). After 17 years, such an otherwise humdrum event is unlikely to have been retained!

The taxi driver was probably a gem. I had been drawing a blank in recall, beyond the—now correct—appearance of the airport, and then he suddenly appeared. In weak memories, there is sometimes a pattern in which nothing can be remembered and then one constituent comes back. This constituent tends to be of particular interest or emotion. Once it returns, other material—previously not available—may then follow. A student of mine, who had participated in a project involving personal memories, noted this same phenomenon. The part that suddenly came back he called a “gem.” In my own experience, it’s more like a chimney pot that appears suddenly through a fog. Anderson and Conway (1993) have described either an identical or a similar phenomenon as “a strong element.” Again, interest or emotion tends (in the view offered here) to be critical. In the case of the taxi driver, his talking with us opened a small window on his culture, and the topic of marriage, given the suggestion that my (9-year-old) son might want to marry a Moroccan woman strongly caught my interest.

I recalled the driver as “tallish.” There was no mention of height in the original journal, and so this constituent was scored as an error (although it may not have been).

I remembered some confusion at the airport, and trying to talk to people behind a desk. This was again a time-slice error, in which the day of arrival was confused with the day of departure: the confusion happened in the arrival episode. (Interestingly, when I first recalled the day of arrival, I failed to recall the scene of confusion. I then mistakenly recalled that scene when I shifted to the correct target day.)

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I questioned the accuracy of the Crunchie element in the goingto-a-store scene, after recalling it and at first accepting it. The journal revealed that the episode occurred, but the Crunchie element was indeed incorrect.

At the end of the report, I tried—pushing memory a little now—to recover other details. I thought of a blue and white drum and a bus ride. In both cases, this material did not seem to qualify even as a “1.” The source of my questions here, though, was different. The Crunchie had returned with a sense of plausibility, embedded in the recollection; however, I realized that it was an unlikely element, based on outside knowledge. In the other cases, there was no feeling of the correct time or place tag: the material returned, but it did not seem right.The drum proved to be another instance of source misattribution: it dated from the return plane ride on Moroccan Trip 2. But it had received a ? during the attempt at recollection.

Of this overall memory, concerning content scored at a 1 or higher (content that I thought might be accurate but with a low degree of confidence), 94% was indeed accurate. 4% involved outright errors (the tall driver and the Crunchie bar), and 2% were source misattribution (timeslice) errors, in which a constituent of the airport scene on our arrival was confused with the departure airport scene. This involved some uncertainty as to how to proceed in the airport and talking to someone at a desk, which belonged to the day of arrival (the flight from Casablanca to Tangier). The material was scored based on propositional units.

I did not include in this count the major time-slice error, in which I began at first to recall wholesale the day of our arrival, because I had rejected it as the correct, target memory at the time.

Input-Bound and Output-Bound Memories Koriat and Goldsmith (1994) and Koriat (2000) distinguished in episodic recall between “input-bound” and “output-bound” measures. The former involve the body of information that is retrieved in the attempt to remember a given episode; the latter involves a judgment process concerning which components of the information should be accepted as being accurate. Clearly, an individual who accepted all or almost everything that was retrieved as reflecting the target memory would often display a high level of invalid content. Thus, the extent to which humans might be measured as recalling the past accurately could vary a good deal (for the same retrieved content between those who accept and those who question). However, there is no evidence that people generally do behave, concerning this issue,

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in a noncritical manner. At least the habit of doubting our weak memories (“Am I remembering that, or imagining it?”) seems fairly universal.

It should be noted that most material that is rejected is not inferred content. It is simply content that corresponds in part to the operating cues, but reflects the wrong event.

Episodic Recall Versus Word-List Recall In the day-of-departure episode described above, the target was defined as beginning at the start of the relevant day. If this definition is accepted, then there were neither primacy nor recency effects here. Also, the same pattern (absence of primacy and recency effects) was shown across all 22 delayed memories that I chronicled. This finding provides a striking difference between episodic memory and word-list recall. In the latter, primacy effects are huge—basically, lynchpins—and recency effects tend to be quite strong too.

The finding here is not difficult to explain, however. The events involved in getting up, having breakfast, etc. are repeated with small variations each day. So the same “getting up” header must be involved across time in thousands of links to both repeated and slightly different actions, on Day 1, Day 2, Day 3,. .. to Day X. This is the classic pattern for producing marked similarity-based interference. Added to that negative influence, the getting-up actions are of very little interest. And breakfast suffers from the same difficulties.

An identical explanation can be offered for my abysmal recollection (from the 4-year-delay period on) of the car, bus, or plane rides that began each trip. Primacy and recency effects would have been offset by high levels of, again, similarity-based interference. Here the same cue (the header) is associated with a large number of similar events, i.e. events that show little distinctiveness, one to the other. The organization of these memories is shown below.

Plane Trip Trip 1 Trip 2 Trip 3 Trip 4 Trip 5 Trip 6 Trip 7 Trip 8 Details Details Details Details Details Details Details Details (all similar).

Mushing Findings of this kind have been reported consistently in the literature on autobiographical memories. Here it has emerged that we recall details from unique episodes quite well, but that details from repeated, similar episodes

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are lost with the passage of time (Linton, 1986; Nelson, 1993). For instance, if you have only taken one major exam in your life, you may well remember that someone kept sneezing, and that a window near you was open.

But if you have taken dozens of examinations, the details of each are soon forgotten. The effect has been called mushing. It is a pretty standard interference effect.

A point of interest, concerning mushing, is that the interference operates across different episodes, and across extended periods of time.

In general, I have found primacy effects in the journaled memories to occur at the point where we arrived at a new place. In contrast, there have rarely been recency effects involving the vacation events of the last day. I have no doubt that both primacy and recency operate in episodic recall, but it emerges that these factors can be overridden by the effects of interference, in particular, and probably low interest value too.

In episodic memory, as noted above, interest, emotion, and uniqueness appear to completely trump other factors, such as primacy and recency.

MEMORY OF THE MOROCCAN TRIP: A SUMMARY BASED ON THEORY The following properties characterized the present memory. They are also characteristic of other remote episodes that I have journaled.

• In trying to recall a memory, nontarget content will often be retrieved.

This content usually involves a partial match with the cues.

• Once content is retrieved, if it appears weak or uncertain, we evaluate it. For personal memories, it is often possible to identify something in the content that clearly shows it comes from the wrong episode.

For instance, when I recalled standing in a corridor inside a school, I realized that this retrieved memory could not be part of the target, in which we were standing outside near some barrows. The other striking finding is that there is sometimes a kind of subjective sense corresponding to “this happened.”This may relate to Tulving’s (1985) idea of noetic experience, in which there is some kind of code indicating that this is indeed an episode through which you, yourself, lived. But this can be very weak, such that it is not safe to rely on it. Yet at other times, it is completely clear.

• The retrieval of incorrect content can occur even when you are potentially capable of retrieving the correct memory and later (after rejecting the false) succeed in this. The explanation I would offer here is that if

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a competitor memory is strongly coded, it may be retrieved as soon as some elements of the cues make contact with it. The strength, under this hypothesis, is often present because the competitor involved emotional material. My substitution of the day of our arrival for the day of our departure at Casablanca, described above, could be attributed to the factor of emotion. I would hypothesize that a distinct sense of interest may have the same effect.

When time-slice errors occur, there is higher-order content (a header) into which the inaccurate content fits. The fit can be highly precise.

There may be a pattern in which, if a context is established, and some material, Y, fits exactly into this context, Y may tend to be transposed into that context.

There are times when an attempt at recall first retrieves nothing, until a special element, or what my student called a gem, appears. This does not typically involve the beginning of the target episode. The finding that beginning to recall content from a memory set leads to the retrieval of other content is in flat opposition to the data on word-list recall, where the recall of some material from a set tends to impair the capacity to recall other material from that set (MacLeod & Saunders, 2008; Malmberg, Criss, Gangwani, & Shiffrin, 2012). These differences require some explanation.

Reminiscence occurs in personal memories.

In both word-list recall and episodic recall, a good strategy for success is to begin at the beginning and move through the material sequentially. The available data are scant, but support the view that the processing structures that achieve this are the same for both. However, several factors can override this function. In episodic recall, if a gem occurs there will be a shift to that content, which may break the ongoing temporal or order sequence. For instance, I was already in the airport (in memory) on the last day when I recalled the (high-interest) taxi driver who had been encountered earlier. Recall then went back to him, and later proceeded again to the airport element. The recall function seems to have no difficulty in moving backward or forward in time to resume the temporal sequence. (Given the power of gems, why did my recollection of this target day begin with the airport scene? A simple answer seems available here. The emotional arrivalday scene had been retrieved first, and included a lot of information about the airport element. When I realized my mistake, “airport” was operating strongly as a cue, having been activated again and again,

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such that it apparently led to the retrieval of the now-searched-for correct airport scene.)

• An incorrect recollection, if it is caught, does not prevent the subsequent retrieval of the correct recollection. This property of episodic memory appears, again, to be somewhat at odds with established patterns in the recall of random verbal items. The issue will be examined again later.

Implications for the Organization of Content in Long-Term Memory There has been a long tradition in memory research in which it is assumed that information reflecting a given event will be coded together, as in a file or single body of content, while information from a different event will be coded in a separate file, and so on. This view fits a copier theory: the experiences occur separately, and so the memory content could be expected to duplicate this characteristic.

Schank (1982) wrote that he had originally accepted the idea described above, of separate and bounded files for separate episodes. By bounded is meant that the information in File A would not form associations with, or interact with, information in say File B. But Schank found that the data on memory did not, in his view, fit this assumption. For instance, you might confuse in memory the appearance of a doctor’s waiting room with the appearance of a dentist’s waiting room. Perhaps there was a fish tank at the dentist’s and you recall it as being at the doctor’s. If the older theory were correct, the doctor visit should all be in the same body of content, and intrusions from another recollection would not be expected. But such intrusions do in fact happen.

The critical factor here, Schank noted, stems from the similarity in the higherorder meaning codes. In other words, a conceptual header such as “medical visit” would subsume medical visits in general, on a semantic basis; associations would lead from the higher-order description to events subsumed under it, often moving for this reason across separate episodes.The idea is shown below.

MEDICAL VISIT A. Doctor visit B. Dentist visit waiting room waiting room

This pattern was found in the present example from personal memory, and has consistently been found in cases of source misattribution across my recorded holidays.

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Does the presence of intrusions, such as the misrecollection of the fish tank described above, provide clear support for the view that memories in LTM do not involve boundaries, across which associative connections are unable to pass? It emerges that these data do not supply certain proof of the claim: researchers oriented toward the more traditional view have been able to interpret the findings based on a cuing assumption. Under this hypothesis, memories are indeed isolated and bounded in LTM, but cues can mistakenly enter a nontarget memory, B, and retrieve its content into awareness. In other words, the doctor office visit remains isolated in the long-term store, but when you are recalling the time you went to the doctor, cues such as “medical visit” might access the dentist memory (moving directly between working memory and LTM) and retrieve a fish tank representation into awareness. This issue is explored in detail in Chapter 7.

Thus, an opposition has developed between researchers who posit that LTM preserves an unchanged representation of a given episode, which remains isolated from other information in the store, and researchers who hold that the memory function is geared more to the development of the most useful information possible (which implies interaction within LTM), rather than to maintaining close duplicates of original experience. The former reflects a position derived from philosophical empiricism, and the latter a position derived from philosophical constructivism. The opposition, though, has been amazingly persistent over time.

Under the present view, the memory function certainly does identify individual episodes as such, and maintains this information to a considerable extent. But this is not achieved by placing individual episodes in some kind of bounded set or file. It is simply coded as information associated with the relevant events. In the example used above, there will be a link between the “Moroccan Trip 1” header and all the events of Moroccan Trip 1.

This provides the information that the subset information came from the same memory: there is no requirement for the information to be stored in some individual file to provide this datum. At times, though, links from the header to related but nontarget content are stronger, and the associative movement passes to the content they have activated. These issues will be explored further in Chapter 7.

It should probably be mentioned that a 94% accurate recall of a time dating 17 years into the past does not imply high levels of distortion in human memory. Distortions certainly occur, but they do not seem to overwhelm the things we remember.

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SOME FACTORS INFLUENCING MEMORY RETRIEVAL Many of the properties identified in the area of word-list recall generalize directly to episodic memory. There is the clear work of temporal or order structures that enhance recall by means of moving from the earliest point at which an episode can be recalled sequentially through the events that followed (as described in Chapter 3, within the context of word-list recall).

While special elements often overrode this factor in my recollection of the Moroccan day of departure, the tendency of sequential movement was also clearly evident.

Positional Coding There is another important property in which random item recall corresponds to our recollection of autobiographical events. This pattern was not shown in the present example, but Burt et al. (2001) have reported a reliable tendency in the case of personal memories for the following. When a given element is not recalled in its original position in a sequence of events, it tends to be recalled very close to that position. This again corresponds to what occurs in the case of random item recall, again as described in Chapter 3.

It is very likely that the exact mechanisms (still being researched) that produce these two results in list learning are the same mechanisms that operate in episodic recall.

Retrieval Cues In other cases, extrapolation from list recall does not work well within the present context. As noted above, recall of some information from a target episodic memory does not impair the capacity to recall more information from that memory: on the contrary, recall is typically enhanced. The opposite is true for word-list recall. And as will be explored in later chapters, retrieval cues in fact often function quite differently within these two contexts.

Another set of issues also emerge from recollections of the kind described above. It is clear that recalled memories do not typically reflect the information with the strongest activation level in LTM at that moment in time. There is content in my own long-term store that is more strongly coded by far than the memory described above. But in a deliberate attempt at recall, what might be called a particular channel for the return of content to awareness is established.This channel is dominated by the operating cues; whatever information in LTM the cues contact that is specific to those cues

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and that develops an adequately high level of activation—that information will be recalled.

Tulving’s lifetime work has demonstrated the following. Given the power of cues to strengthen a memory with weak background activation, the extent to which the cues overlap with target memory content determines the probability of that target being recalled (Eysenck & Keane, 2010; Tulving, 1982, 2002). In contrast, some content with what Tulving calls “high quality” will require only minimal overlap. The issue of high quality is introduced again below.

Discriminability Yet a third factor operates to influence recall. This involves the function of discriminability. Roughly, a unique memory is easier to recall than a memory that exhibits similarity with other memories (as was perhaps all too obvious above). The implications of discriminability have been explored in some detail by Nairne (2001, 2002a, 2002b, 2006) and by Hunt (2003, 2006). Under Nairne’s view, the following is the case. The overlap of cues with the content of a memory is of course a critical factor in recall, but the extent to which a given cue is associated with many different memories inversely correlates with the power of that cue to elicit any of them, including the target. Thus, the basic assumption of cue-memory overlap is that the more extensively cue content matches with a target memory content, the easier it is for that memory to be recalled, in the case of weak recollections, but this is not always true. (Part of this last sentence was italicized because, as noted above, this general rule does not hold for strongly coded memories.) However, returning to weakly coded information, the perhaps counterintuitive implication of discrimination theory is that the following can occur. Increasing cue-content overlap may actually decrease the ease with which a memory can be recalled, if the cues that provide increased contact with, say, Memory X, also overlap with Memories Y and Z. In part because cues are less effective with the more targets they contact, it is possible that a cue or set of cues, say R, that match uniquely with Memory X may provide easier recall of Memory X than cues R and S working together, even though S also overlaps with Memory X. This is because S makes contact with Memories Y and Z as well, and the activation of those potential competitors may slow the point at which Memory X may reach the threshold for recall (or even cause X not to reach that threshold, and so not be recalled). That this former outcome

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does occur was demonstrated empirically by Poirier et al. (2012). One caveat might be mentioned here, however. The materials in the Poirier et al. study involved learned and arbitrary associations between the cues and the targets, as against a form of contact that involves an identity match between cue content and target content. For instance, if a cue is beak and the target memory involves a bird eating a seed, there will be an identity match between the cue and a property of bird almost certainly coded into the memory (e.g. beak). In the Poirier et al. study, participants might learn that being tall and good at mathematics, although not at history, were properties of John, such that these qualities in the test would serve as cues for John. The associations here were arbitrarily learned. However, the data strongly suggest that the same outcome (of distinctiveness issues sometimes overriding cue-memory overlap) would hold for matches that do not involve arbitrary learning.

How well do these claims generalize to episodic memory? The account of “mushing” giving details of multiple similar episodes with the same header (e.g. “taking an examination”) appears to fit well with distinctiveness theory. Here, an identical cue is associated with multiple, similar episodes. And my very bad memory for the various plane trips of the past shows the same pattern of impaired recall.

One of the most striking outcomes of almost any attempt to recall a distant episodic memory involves the return of nontarget information to awareness. These nontarget scenes typically match with the cues, but not of course with the full set of cues. Early associative models such as FRAN posited that word items are recalled when the system reads a “tag” within LTM, specifying that a given word was present on the previously learned list. If the tag is present, then that item will be retrieved. But the strong tendency to recall nontarget information (both in list learning and episodic recall) does not suggest a strong function that selects the material prior to its entry into awareness. Instead, it appears that once the operating cues have been established, they contact material in LTM on a matching basis and if that material is coded at sufficient strength (including the additional activation provided by the cues), it will be retrieved. Thus, partial cue-memory matches frequently result in the recollection of the wrong content. Two possibilities then emerge. In episodic (but not word) recall, the individual can often determine that this material is incorrect based on knowledge relevant to the memory (e.g. it is unlikely that I would not have experienced pleasure over being in a country again on the day of my departure from that country). The second outcome involves something like

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an assessment function. Subjectively, it corresponds to, “Does this feel like the right memory?” In some cases, there is no doubt of the issue. But in others, i.e. the weak memories, the assessment process is needed, and comes into play. It is clear from this pattern that the memory function does code information specifying the relationship between the header for a memory and the relevant content. A header-subset link would be enough to provide this datum. But this would be the equivalent of the “tag” information described above. If such information is present in LTM, why does it not prevent the retrieval of nontarget content? The obvious answer appears to be that the subset links are often relatively weak, while the system’s response when cues match content in the long-term store can be very strong. The former can override the latter.

Coding Strength Tulving (1982) wrote of the quality factor in memories. It is the same property that I have designated simply as strength of coding. In the case of strong memories, there need be only enough cue-memory overlap to specify the desired memory, and that memory will be retrieved; that is, the overlap can be minimal. Thus, a partial cue overlap with a strong but nontarget memory is at risk to retrieve that memory. But what then provides the strength factor? In word-list learning, strength can only be generated through actions such as rehearsal, or other consciously controlled strategies (perhaps the forming of images). But no such strategic work operates in the forming of typical episodic memories. We live through a sequence of unfolding events just once, and the majority of these episodes will not be rehearsed later, although some may be rehearsed (reactivated) briefly in conversation or thought. But, again, episodic memories can endure with no form of rehearsal at all. This is because they are constructed by a matrix of powerful schemas: schemas with multiple inter-associations that provide the capacity to maintain information much as the steel girders of a building may support wood and cement. The function operates unconsciously and easily, and requires no “strategic” work. But in addition to this factor (present in all episodic memories), the argument will be pursued here that both emotion and interest serve to directly enhance the capacity of human memory in its work of retention. The arrival scene at Casablanca was more strongly coded in my own long-term store than was the scene of departure, due to the factor of emotion, and so was able to reach the threshold for retrieval before the episode that fully matched the cues (the day of departure).

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Some Final Thoughts I would like to end the present chapter with some thoughts concerning the Crunchie bar.

I have checked on the issue of the existence of jumbo Crunchies with some friends, and no one has ever encountered one. It seems they do not exist. So my recollection was not a time-slice error. If there are no jumbo Crunchies in the world, I could not have recalled trying to buy one during some other episode.

My journal revealed that I had in fact tried to buy a jumbo Cadbury’s chocolate bar. So the Crunchie was an inference, but a peculiar one. I have encountered far more Cadbury’s bars in my life than Crunchie bars. Why would my memory function deduce a less familiar object, in preference to a more familiar object? In other cases, the pattern of inference has favored familiarity (and, presumably, actual existence).

As I was thinking about the issue, an idea came. It was the notion that a certain (well-remembered) woman, who had traveled with us when I went to Tangier as a child, had given me a Crunchie bar. She had given me the Crunchie in Morocco. And on that trip we had definitely boarded the plane in England. The recollection is so hazy that it could hardly be called a recollection. But if this is the real explanation (and it is a very large “if ”), the implications for human memory—for its sensitivity to very, very weak associative content—seem profound.

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Piaget’s Model Chapter 5 centered on a description of constructivism as offered by Sir Frederick Bartlett. The other great theoretician of the twentieth century, in the present area, was Jean Piaget.

Piaget noted in his 1973 book on memory, written with Barbara Inhelder, that he accepted all of Bartlett’s claims, but would go a few steps further. One of his most important further steps concerned the variable of strength in human memory.

THE GENEVAN VIEW OF HUMAN MEMORY Under the Piagetian (or Genevan) view, when episodic content fits the higher-order, interpretive structures, that content will be strongly retained, compared to content that has no structure into which it might fit (i.e. random information). This was also Bartlett’s fundamental claim. But in addition, Piaget suggested, all the relevant structures belong to a background organization, which will determine the level or degree of strength that they provide to a memory.

When information is to be established in long-term memory (LTM), it is constructed on the basis of schemas. For instance, if an individual encounters a boat, then the nature of the object will be provided by a boat schema in the long-term store. The second critical function of the schema is that it strengthens the relevant memory codes. Under the Genevan view this occurs for all schemas; not just for those described as higher order.

Thus, memory for a thing that can be identified will be stronger than the memory for a thing that cannot be identified, i.e. an unknown object that does not correspond to any established concept.

Piaget’s view was that schemas differ in their potential to supply strength to a given memory: some can supply more strength than others.

This is the case because the schemas themselves operate as part of a background organization in the long-term store. That is, they are interrelated in a matrix of information. Some are more tightly interrelated (with other schemas); some are relatively isolated. The more extensive the connections

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for any given schema, the more strength it can supply to a memory when it is used in the construction of that memory.

According to the present model, when I form a memory of even so simple a thing as a table, my cognition draws on both the table schema, which supplies the object with meaning, and also on the relevant perceptual schema (specifying the appearances, shapes, sizes, etc. of tables). For instance, if the far end of the table is in darkness, I will nonetheless know that it is supported at that end, in parallel with the end I can see, by two legs, and also that its surface continues to be flat in the area that I cannot see.

Note the pragmatic aspect of constructed information. I cannot see the far side of the table, but this does not prevent me from accurately identifying its shape. If someone tries to put books on the further surface, I will not call to stop them. I know that the books will be supported: and they will.

Constructed knowledge is generally accurate in just this way.

Even so, the useful information supplied above can involve a small penalty in the case of recall. For if I remember the table some days after, I may “remember” seeing the entire stretch of flat surface, although in fact I did not see this. Human memory is at risk of reconstructing things as they actually are, rather than those precise aspects of things that were seen or heard, such as half a table. The argument could even be made that constructed information is more accurate, in some fundamental way, than many forms of perceptual information: the table really does have four legs. At any rate, I could incorrectly recall that I saw the entire surface and the two legs at the far end.

This implies that human memory, although it may carry very precise images for a period of time (often a brief period), is not fundamentally oriented toward this kind of camera-like function, i.e. the exact duplication of percepts. It appears oriented instead to the best available knowledge.

The meaning code relevant to the table is more important in this model than the perceptual code. And the two are fundamentally distinct. The first involves “what a table is,” and the second involves the way tables look. Also, the most important codes of the former involve activity information, such as what a table can do, and certainly how humans can use a table. Note that this is again useful information.

Semantic Versus Perceptual Coding In many traditional mainstream approaches to human recall, such as Baddeley’s first formulations of working memory, there exist structures to hold auditory and visual (and perhaps other sensory) information, such that our awareness involves exclusively perceptual content (Baddeley, 1986,

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1990; Baddeley & Hitch, 1974; Baddeley & Logie, 1999). It should be added, though, that semantic information has been included in Baddeley’s most recent formulation (Baddeley, 2002).

In contrast with the emphasis on sensory information that has characterized Baddeley’s work, in the Piagetian model the most important aspect of our thoughts and memories centers on meaning (semantic) codes. These are the major functional players in human awareness. Again, it is more critical, if I am looking at, say, a kettle, that I understand what it is (instrument for boiling water) than that I grasp the details of its shiny convex visual outline, or any of its perceptual features. It is also the case that in the act of recall, under both Bartlettian and Piagetian theory, I may well remember that there was a kettle on the stove without being able to recall its individual appearance.

The importance of meaning codes, however, is just the beginning of the story.

If I am visiting a friend’s kitchen and see a kettle, the kettle will relate to everything around it on the basis of my background knowledge. I know that these objects are typically found in kitchens, and also on the surface of stoves. The concept fits into the somewhat wider kitchen context. The latter involves an extended body of information.

Under the Piagetian view, the more a stimulus fits into a complex of background knowledge, then the stronger will its representation be in the long-term store. I may see the kettle just once but be able to recall it fairly well. If recalling its appearance is the issue, part of this capacity could be inference. But the assumption here is that in addition to the possibility of inference, the fact that the kettle did fit into a matrix of other schemas will serve to strengthen its coded representation in that particular memory.

Of course, most objects that we encounter in daily living also fit into a background context. So it might be argued that the context provides no particular strength; it is just “normal.” And it is normal; however, this function can be contrasted with our ability to recall a series of random objects shown on a screen or a series of random words. These items carry individual meaning (they represent concepts), but fit into no extended context.

As a result, our capacity to retain them is weak; we have to rehearse the objects to remember them later.

The Role of Higher-Order Schemas As the information entered into memory extends to higher, more generalized and extended levels, so the matrix of schemas supporting that information provide greater support. It has been solidly established, for example,

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that personal memories are organized in a hierarchy of more general to more specific information, and that the higher-order, more general levels tend to be (considerably) better retained than the lower details (Barsalou, 1988; Brown, Shevell, & Rips, 1986; Conway, 1996; Conway & Bekerian, 1987; Linton, 1979; Schooler & Hermann, 1992). The Piagetian view here provides an explanation of why this should be the case. Higher-order content is constructed by schemas, each of which is integrated into the extensive manifold of schematic content below it.

Another function of the higher-order schemas is of course to provide the capacity to anticipate events and actions. If I see a friend pick up an empty kettle (especially if he has just asked me whether I would like coffee), I will expect him to go to the tap for water, and back to the stove, and turn on the stove, and so on. The same holds for the bulk of actions that we see around us. And, again, these predictable actions will be significantly better supported in memory than a series of random actions; the latter would lack the same schematic support.

It is true that a single event that does not fit expectation is likely to draw our attention to it, and so be remembered. If my friend picks up a kettle and then puts a book in it, I shall remember. But the real weakness of such events in human recall is demonstrated when an entire series of nonexpected (i.e. higher-order schema-violating) events are encountered. Special attention cannot be maintained for so long.This does not occur in everyday living, but can be modeled in prose (as in The War of the Ghosts battle scene).

Knowledge Structures Researchers working in a quite different tradition, that of computer simulation, reached the same conclusion as the original constructivists. The attempt here was to develop programs that could handle ordinary prose, in the sense of answering questions appropriately. Paul Abelson and Roger Schank noted that earlier attempts in the field of linguistics had failed because the models had not included extended background knowledge (Schank & Abelson, 1977). Such knowledge, the authors concluded, was essential. Even simple sentences (“The policeman held up his hand and stopped the car�) cannot be understood without it. Further, when, and only when, encountered information fits the background knowledge (called knowledge structures by these authors), it makes sense to the individual and, again, the capacity to remember the information is strengthened.

Here, there are background structures, and content that can be assimilated to them is strengthened in memory. The structures can supply

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inference, and thus could provide distortion in some cases, but their primary role is positive—just as schemas, including higher-order schemas, are seen as providing a positive role in the hard-line constructivist tradition.

What of schemas that cannot integrate to any great extent with other schemas? The information they construct would be poorly recalled. The lower-level constituents of an event, the details, normally fall in this category. Perhaps Jane went with friends to visit a museum 6 months ago. The fact of going to the museum will probably be recalled after the 6-month period; the museum schema involves a large body of integrated knowledge.

She may even recall that an attendant asked her to stand back from one exhibit, behind a designated line. And perhaps the attendant’s uniform was a pale green. After this period of time, though, Jane probably won’t recall the color of the uniform. This fact integrates with nothing: the uniform could have been blue or beige or brown. There are few constraints on memory here; color concepts have very little in the way of extended, “fixed” (invariant) relations with other concepts. In summary, arbitrary elements in a memory have minimal schematic support, while nonarbitrary elements do enjoy support of this kind.

Under the present model, behind each human memory lies a vast body of (for the most part) nonarbitrary information. Each participating schema typically involves a highly extended body of knowledge, and what is involved, as we live through an event, is not an additive accumulation of the codes provided by the schemas, but coherent integration among them. Rehearsal is not needed to retain the content of episodic memories; many such episodes are remembered across a limited period of time, and other content can be retained across long periods, sometimes extending to the end of life. This contrasts markedly with our capacity to retain a list of words, where rehearsal or other conscious, strategic processes are needed for memorization. This, again, is because the list lacks any integrated support of one item with another, or any word with background knowledge beyond the concept for the word itself. Critically, however, under Piaget’s model, while all these coherent relations hold for an actual episode, say Episode X, in addition to such relations the background integration of each schema with other schemas (schemas that may play no role in Episode X) is also a determinant of the strength of the constituents in the memory.

In the forming of memories in daily life, we rarely rehearse, or use other conscious strategies to retain the relevant information. Retention is automatic. If I am told there is going to be a major rainstorm at five o’clock, I

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do not need to decide how to hold this information and, perhaps choosing rehearsal, walk down a hall repeating, “Major rainstorm, five o’clock; major rainstorm, five o’clock.” Thus, within a tradition that emphasizes the power of schemas to maintain information in LTM, there is less emphasis on the role of conscious activity, or “control processes” in the work of memory as such, as compared to the emphasis that has emerged from the study of random verbal items. Conscious activity, under the hard-line constructivism view, is something of a second fiddle.

It has been established that under certain conditions of damage to the brain, including many forms of senility, it is the “lower,” more concrete concepts that are lost first. An individual who no longer possesses ideas such as “pig” or “deer” will continue for some time to understand “animal,” or if ideas such as “hammer” and “pliers” are no longer functioning, will still understand “tool.” As the brain deteriorates further, the higher-level concepts are lost too ( Warrington & Shallice, 1984). These data also support Piaget’s claim.

Non-Divorce Hypothesis The Genevan position necessarily implies what might be called a nondivorce hypothesis. When schemas construct information in the form of a memory, there is no point at which the associative contact between the schemas and the memory content ends: the contact is always there. And, again, it is always critical to the issue of memory strength.

A conclusion might be helpful here. Under the Piagetian model, a body of interrelated schemas in LTM provides greater strength to a newly formed (or an old) memory than does an isolated schema or a set of relatively isolated schemas.

This function involves both the degree of internal coherence of material in a given episode, or prose passage, or any other medium. It also involves the extent to which the schemas involved in the memory display extended, as against limited, background integration within the system of schemas in the long-term store itself.

VISUAL CODES IN MEMORY: FIGURAL ELEMENTS AND PERCEPTUAL SCHEMAS As outlined in Chapter 4, under Piaget’s model a visual memory consists of two separate components (Piaget, 1969; Piaget & Inhelder,1971). They involve fundamentally different kinds of code. There is the “figural” element, which reflects a capacity to retain noninterpreted lines or colors: a camera-like, but weak, function. By “weak” is meant that although a general

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sense of the lines of a visual stimulus may be maintained, this tends not to be precise or exact, and in and of itself would be quickly lost across time.

The other component of a visual memory is provided by the relevant perceptual schemas, which supply knowledge concerning the appearance of the stimuli; knowledge of the appearance of, say, a table or a cat. Critically, the two (i.e. figural and perceptual schema-supplied) components then work together to generate the experienced visual percept. Prior to that time, the activation of the perceptual schema will also activate the associated concept schema (Piaget, 1969, 1977). This general model of the cycle of processing has been supported by extensive research within mainstream work in the area of perception, including the view that these events unfold at a preconscious level until the point where both the visual image and awareness of the identity of the stimulus appear in awareness simultaneously (Broadbent, 1977; Howes, 1990; Kahneman, 1973; Treisman, 1970).

In contrast, the claim that figural information is routinely supported by perceptual schema content even at the time of encoding (as well as at retrieval) has not been widely explored in the mainstream; nor has the view, outlined below, that concept schemas literally strengthen the capacity of visual memory content (as well as semantic content) to be retained in LTM. According to the latter position, a stimulus that can be identified will enhance the capacity to recall the visual aspects of the stimulus.

Although this may be obvious from what was said in the last sentence, it is not the case in this model that visual and conceptual memory are simply inter-associated, so that the activation of one will lead to the activation of the other: the meaning codes for an object literally provide strength to the relevant perceptual memory images, i.e they have a supporting function.

I once framed some photographs of undersea life of various kinds, but such that I could not have looked at the images and identified the nature of even one (i.e. that it was, say, a polyp). Some while after I was asked about the pictures, and discovered an astonishing inability to visualize them. I could not possibly have drawn them from memory. And although I am a low mnemonic visualizer, if I am shown pictures of identifiable objects, I can do a fairly good job of drawing from memory.

An important point is that there is no camera-like function here, under any circumstances. If visual or auditory information can be interpreted, it will be interpreted at the time the memory is formed. In short, there is never a situation in which potentially meaningful lines or sounds are picked up and coded “by themselves.� There is no pristine memory that does not involve construction, nor any memory record that is not the product of

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earlier construction, with the exception of random lines or random noises, or some less-utilized sensory stimuli (e.g. touch) that do not normally activate concept schemas.

When Concepts Influence Percepts in Memory: Carmichael, Hogan, and Walter’s 1932 Study One of the most famous demonstrations of the relation between ideas and imagery was provided many years ago by Carmichael, Hogan, and Walter (1932), who showed how a label (reflecting a concept: a schema) can shift the relevant memory image in the direction of the concept. If the label is “pair of glasses” the memory image will emerge as somewhat like a pair of glasses; if the same picture is labeled “dumbbells,” the migration is toward a dumbbell-like image. The material is shown in Fig. 6.1.

Some Reproductions

Label List 1

Original Stimuli

Label List 2

Curtains in a window

Diamond in a rectangle

Crescent moon

Letter “C”

Some Reproductions

Eyeglasses

Dumbbells

S e ve n

Four

Ship’s wheel

Sun

Figure 6.1 The influence of schemas on memory imagery. Carmichael, Hogan, and Walter (1932) found that participants viewing a neutral image, two circles connected by a line, would later reproduce the image as a drawing from memory based on the label applied to the neutral image. For example, if the image was labeled “eyeglasses,” as in List 1 above, then participants’ memory drawings would migrate toward the eyeglass image above on the left. Similarly, if the image was labeled “dumbbell,” as in List 2 above, then participants’ memory drawings would resemble the image above on the right.

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Mainstream models have difficulty with these findings. The traditional explanations tend to involve different “paths” taken to locate the target in LTM, as in Paivio’s (1969, 1991) work. In contrast, the Piagetian view predicts just these results.

Another critical prediction of the present model is that, as in the sea-life example offered above, we humans show poor recall for visual stimuli that do not correspond to any concept, as compared to stimuli that do. This is of course because when we see a familiar object, we do not commit the entire set of line contours to memory, but rely heavily on the underlying perceptual schema. As noted above, though, it is the case that some literal “copying” of a familiar stimulus is achieved. In contrast, for a meaningless image, only the figural copying function is available (see Fig. 4.1).

Figural memory does not possess the property of integration. One set of line contours does not inherently relate to other sets. As far as their internal codes are concerned, any contour could be connected to any other contour.

This is in sharp distinction with the schemas that provide meaning codes, as described above. It may be why figural recall alone tends to fail so quickly.

In conclusion, even the idea that there could be a level of recollection involving visual content only and derived solely from experience (i.e. from potential information in the light waves entering our eyes) can be seen to be false. Even the images that we recall incorporate knowledge derived from the long-term store, and therefore knowledge that has been provided by the human mind and not acquired from the world. It’s a mixture.

GENEVAN AND MAINSTREAM VIEWS OF EPISODIC AND SEMANTIC MEMORY In the condition known as the amnesic syndrome, again resulting from damage to the brain, individuals lose the ability to form new episodic memories (so-called anterograde amnesia) and there is often extended loss of memory for certain stretches of time in the past (retrograde amnesia). These conditions can co-occur, or one form of amnesia may be present without the other (Butters, 1984). In contrast, semantic memory, involving concepts and general information (“Paris is the capital of France”) typically remains unimpaired in these amnesias (Albert, Butters & Levin, 1979; Moscovitch, 1992; Parkin, 1987; Squire, 1981; Winocur & Kinsbourne, 1978). Semantic memory appears in general to be far more robust than episodic memory: when you acquire a new concept, it is most typically retained, even across years, while memories for many events in the past are forgotten.

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Core Properties of Concepts Under the Piagetian view, semantic memory enjoys a higher level of schematic integration than is the case for episodic memory (Piaget, 1926b, 1972; Piaget & Inhelder, 1973). Piaget’s model of conceptual (schematic) structure falls to some extent in the neoclassic Aristotelian tradition, which has been unpopular within the mainstream field almost from the onset of research in that field. (A few exceptions, such as Jerome Bruner’s 1957 work can be cited.) Under the Genevan view, however, concepts both operate in a hierarchy, and show strict logical relations among the various levels (and sometimes within levels). Thus, a concept involves a class of objects, a class being defined as requiring a specific property or set of properties on the part of exemplars if they are to qualify for class membership.Thus, all members of a given concept (schema) will possess the qualifying properties for membership, even though a very large amount of additional information may also be present. Within this tradition, the qualifying properties almost always involve functions, i.e. the capacity to perform certain actions (that necessarily involve interaction with other entities). These are often labeled as the core properties of the concept (Putnam, 1975a, 1975b).

Core properties partly integrate the conceptual schema hierarchy in the following way. The core of each lower-level class includes the cores of all the relevant superordinate classes, i.e. those classes positioned directly above it. Thus the organization of “tree sparrow” can be described as: Tree sparrow → Sparrow → Bird →Animal → Living Thing → Thing.Thus, a tree sparrow “is” all of the classes nested above it, and possesses the core properties of each. (This does not of course work going down the hierarchy.) The present organization implies other logical relations among the classes and information relevant to them. For instance, if there are 50 sparrows and 60 chickadees in a given aviary, there must be more birds in the aviary than there are sparrows—a point wholly obvious to an adult, but not to a young child (Piaget, 1926a, 1926b). Concepts also show certain logical relations within the same level of the overall structure. There is a good deal more to the tradition than has been described here, but the result is an extended matrix of information with strong interrelations among its constituents, and strong constraints on those relations. This tends to provide a powerful supporting capacity for information absorbed into this tightly interrelated matrix.

It should probably be noted that in the case of living things, core information is often derived via biological evolutionary lines. Thus, a bird is a bird because it belongs to a particular group of genetically similar animals

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that specialized in the function of flight many millions of years ago; and specialized in a certain way. Function remains critical here: animals of the same species perform a set of life functions in ways that differ from animals of other species. Under this view, in contrast to the currently popular tradition of various prototype and featural models, any bird belongs absolutely in the bird concept. None is conceptually “more bird” than any other, e.g. an owl is no less bird than a robin. Certain opposing models often emphasize typicality, and would urge that a robin, for instance, is in our cognition “more bird” than an owl (Rosch, 1975; Rosch & Lloyd, 1978).

There have been claims of failure to support the present neoclassic model on the basis of research. However, a typical approach taken in these studies was to ask participants to identify certain “features,” corresponding to what in the neo-Aristotelian tradition would be understood as the core of a concept, which all members of a given conceptual class share in common, and which distinguished them from members of other concepts (Rosch & Mervis, 1975). The instructions led the participants to search for “features” that involved perceptual properties or individual parts. In the case of TABLE, for instance, the search was for something unique such as has four legs (but many tables don’t), has legs (but many non-tables do), “has a flat surface” (but so do many other objects), and so on. The conclusion reached was that there are no core properties (properties shared in common across all exemplars, and that define conceptual-class membership). The problem here of course is that core properties involve functions.

Requesting “features” provided the wrong context. And while schematic content is not believed to correspond directly to words, the core of T ABLE would correspond to something like “this is a free-standing artifact designed to provide a flat surface, held above the ground, to allow people to place diverse objects on that surface (for their greater convenience)”. It remains mysterious how extensive research investigating the Aristotelian neoclassic model could have been performed by researchers who apparently did not understand the basic tenets of the model. Worse, their invalid conclusions have been widely disseminated.

At any rate, under the Genevan view, semantic memory involves a tightly knit organization, while episodic memory, although there is certainly extended integration, is much “looser,” and indeed typically involves a great deal of non-constrained content. For instance, in an actual event, all the particular actions and relations tend to be unique. They are constrained to some degree, but not throughout the entire matrix. On Monday, Jane may have worn a yellow dress and walked quickly to her table at lunch,

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tossing her coat onto a chair. In another episode, Jane will be dressed differently and her behavior will differ. This is also true of every person in every event coded into LTM, and also largely true of the objects with which these persons interact (Boden, 1977). Each episodic memory has to code for a very large variety of separate actions and, to make things even less rule-governed, in general all of the actions could have been different!.

Thus, under the present model, semantic memory tends to be more robust than episodic memory because of the higher internal integration of its content.

CONSCIOUS PROCESSES AND MEMORY CONTENT: A GENEVAN VIEW Piaget made a distinction between the nature of conscious representation, and representation in LTM (Piaget, 1951). Piaget worked explicitly in the Kantian tradition, and under the Kantian view the two aspects of cognitive functioning are different in kind (Kant, 1781/1965).

I have found Piaget’s language here very useful in the attempt to conceptualize memory content, and will use some of his language throughout the present book. Critical ideas include the following. The body of information in LTM that codes for a given memory is called the memory significate. Thus, the stored information concerning what happened at dinner last night is the memory significate for that particular episode.

Signs The schemas in LTM that code for a memory (or other information) possess properties that are (profoundly) different from the representations that appear in awareness. These latter, under the Piagetian view, take the form either of images, or of what Piaget called signs. The term sign is used here to designate the same thing as symbol in the field of computer science. It is an entity that represents some other entity, but does not participate in any way in the nature of the designated entity.Thus, words and images are signs.

CAT represents a certain kind of animal, but the word itself possesses no cat properties. If there were a social convention to use the sign * to designate the same animal, this would do just as well.

Images in this terminology are literally images. Thus, an individual might picture a house that she has seen, the picture being maintained in awareness. This is a memory image. It is also possible to form mental images; that is, generated imagery that does not correspond to a memory.

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I could, for instance, form an image of a river making a sharp zigzag shape, although I have never seen a river like that (and have been told they don’t exist).

Symbolic Images Piaget also identified symbolic images as another form of consciously experienced representation. Here the image does not directly represent the thingsignified, but represents it in symbolic form. Thus, in a dream a tiger image might stand for a sense of danger or aggression. Here the word “symbol� corresponds to its use in clinical psychology and in literature, as against its now standard meaning in the field of computer simulation.

Conscious representation then involves either images or signs. Both represent underlying (nonconscious) schematic information. Of particular importance, in the case of a sign it can be seen as a kind of simple token standing for the relevant meaning (which is present only in the nonconscious schemas). Images and signs together are described as signifiers.

Awareness has a limited capacity to represent information. If you are reading the middle of a story, the opening passages will not be simultaneously present at the center of awareness. Information here is expressed in linear form (one body of content after another). The same is true of percepts. If you are looking at a house, you will not be able to simultaneously form an equally clear image of the sides and back of the house. Thus, information in awareness (and, in current psychological terms, in working memory) is something resembling a simplified token of the underlying codes in LTM. Schemas encode an entire body of information. The perceptual schema for a house includes information relevant to the appearance of houses in general. So does the concept schema for HOUSE code a very large set of information. Critically, these highly extended bodies of (simultaneously coded) content cannot be experienced in awareness as such. The stage of our consciousness does not possess this kind of capacity. It represents in the form of signifiers, indicating the presence of the nonconscious schemas below. The schemas alone directly embody meanings.

The underlying meanings of the signs are tapped, though; they are active when the relevant signs are active. As a reader forms a memory of the content of a book, the resulting complex of schemas and perceptual information codes for all the relevant information, and all the codes are present simultaneously. To be more exact, the system will code on an ongoing basis for all the information that is at sufficient strength to be maintained.

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The Genevan View of Schemas The schemas themselves are not signs, nor are they an intricate compilation of signs. Thus, the Piagetian view differs from many currently dominant models of representation in which concepts themselves are seen as signs, or more exactly as interrelated associations of signs (as noted above, called symbols in the computer and other current cognitive literatures). Under Piaget’s view, schemas can actually code for meanings, i.e. they are not arbitrary forms of representation such as CAT or *. His assumption was that the human brain has some means of coding directly for activity information (the basis of meaning codes), as well as for perceptual information (the basis of percepts).

Here a matrix of perceptual information, size and shape information, and activity information (none of it involving signs) exists in a concept schema.

The meaning codes involved in schemas, in the present model, are probably some form of analog representation, just as the higher levels of sensory coding, and experienced perception, are clearly an analog form of representation. It was posited at one time within the mainstream that perception at a nonconscious level involved symbols, in the computer sense (Pylyshyn, 1973), but subsequent research, particularly by Kosslyn, has established that both perception and visual memory do involve analog codes, just as appears subjectively to be the case (Kosslyn, 2005, 2006; Kosslyn, Ball, & Reiser, 1978; Kosslyn & Pomerantz, 1977). That is, if I am looking at a road that extends physically to the right of the space outside me, I will experience a percept that extends in the same way from left to right across the visual field. The cognitive code corresponds directly to the external object, as against involving signs describing that object.

Further, a schema cannot itself, given the complexity of information that it embodies, enter awareness. Awareness could not hold it.

B. F. Skinner once advanced the argument that concepts (as representations of meaning) do not exist because, when asked, we can’t describe them (Skinner, 1974). The Piagetian view here is clearly that since the schemas (concepts) themselves cannot enter awareness, obviously we cannot describe them on the basis of introspection.

Developmental Processes in Schema Representation It was noted above that under the Genevan view, memory images consist of some figural (literally copied) line contours and input from the relevant perceptual schemas.

The perceptual schemas also act in concert with abstract conceptual schemas. For instance, if I see a series of vertical lines of equal length, the

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visual information will lead to the conceptual interpretation, “Those are lines of equal length.” If I am asked to recall the stimulus, then my cognition will establish, “It was a series of lines of equal length.” At that point, the original figural codes (that they were, perhaps, short lines, spaced close together) will operate in concert with my general perceptual schema for “lines of equal length” to reconstruct the image.

If visual memory works in this way, what would happen if the conceptual schema changed?

Of course, conceptual schemas normally change very little. The idea of lines of equal length has probably undergone no alteration in my LTM since I was 3 or 4 years of age. However, before that point, there was surely change in the relevant concept, and certainly many ideas relating to the properties of things do develop—and so change—across the preschool years.

Piaget and Inhelder’s Research on the Development of Seriation This fact led Piaget and Inhelder (1973, chap. 1) to an explanation of some quite curious data. They had found that in certain circumstances the memory of a visual image would improve across time, in the case of children ranging from 3 to 6 years. That is, a child would see a stimulus and draw it from memory. Then, without the stimulus being shown again, the child would be tested on a second occasion some months later. In a large number of cases, the memory image was more conceptually accurate after the longer delay.

Note that this was not the standard hypermnesic effect. The children had not been shown the relevant images, and then tested repeatedly directly after exposure.

Piaget and Inhelder (1973) hypothesized the following. Suppose a preschooler has reached a cognitive stage where an abstract understanding (the schema) of certain properties is about to develop, or just beginning to develop. Say what is involved is a series of lines, ranging from longest to shortest. If the child sees a series of lines prior to the development of the schema to a higher level, and is asked to draw what he has seen from memory, then the relatively immature cognitive schema will underlie the drawing. If then across the next 6 or 8 months the schema develops to the next higher level and the child is then asked again to draw what he saw some months back, the drawing could improve. This is because the underlying abstract schema (involving in this case comprehension of an ordered series) has improved.

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The research began when some children happened to indicate that they remembered something shown to them 6 months earlier.

There are many forms of abstract comprehension that develop to increasingly sophisticated levels across the preschool and early school years.

They include not only “simple” seriation (i.e. a series of things ranging from smallest to largest, shortest to longest, etc.) but also more complex forms (multiple lines that form a shape, such as the shape of an M); relations between the number of elements and the horizontal space they fill; the quantity of a liquid and its height in containers of different widths (e.g. wide vs. narrow); class intersections, and so on. All of these relations can be conceptualized by the adult (and to a more limited extent by a young child), and all of them can be shown in the form of visual images. Piaget and Inhelder tested possible memory change (reflected by drawn memory images) for them all.

The research involving simple seriation is described below (Piaget & Inhelder, 1973, chap. 1).

Stages of Development in Seriation Ability For the adult, seriation involves an ordered series of stimuli, such as sticks ranging from longest to shortest or, say, potatoes ranging from largest to smallest. Any given stimulus has its exact place in the series. The younger preschool child does not typically possess this understanding (although the abilities appear to be developing earlier today than was the case 50 years ago). At any rate, Piaget divided the advancing cognition into four stages.

In Stage 1, the earliest, the child does not appear to register size differences.

Thus, if a series of sticks are shown, the child understands “There were many sticks,” but without considering the length of the sticks.

In Stage 2, relative size is noticed, and the understanding is something like, “There is difference in size: big and little ones.” Next comes the idea “Big, medium, and little.” Once this idea is present, the child can order three individual sticks correctly, but cannot manage an entire series (i.e. more than three sticks).

In Stage 3, the idea of an entire series is present, but the child, if attempting to copy a physically present model, has to keep moving the sticks around until he can see they “look right.” For instance, he may put a longer stick to the left of Stick X, and then see that it is too long for that position, and try it in another position until he gets the series correct. Also, if the series has been completed, and a new stick is given, the child does not know where to put it in the series.

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Stage 4 is a full, abstract comprehension of seriation, corresponding to the adult’s comprehension. The child knows where to place each stick, and if, after completion of the pattern, a new stick is presented, he will look for the one that is just slightly shorter, and place the new stick to its right (assuming smallest to largest, going left to right).

The stages (reflecting the child’s comprehension of an ordered series) are shown in Table 6.1.

Piaget and Inhelder (1973) conducted a study in which 62 children were shown a series of rods, placed in order from smallest to largest. The children ranged from 3.5 years to 6.5 years in age. This reflected the period across which other children studied by Piaget had developed the seriation concept.

Eight days after seeing the model, the children were asked to draw what they had seen. Controls were included for drawing ability, that is, to ensure that any changes across time in the drawings were not due to increasing drawing competence.

The younger children produced memory pictures that reflected their level of understanding of the model, rather than its actual appearance. Thus, the picture drawn from memory might be of long rods and short rods, or of long, medium, and short rods. Older children came closer to recalling the actual contours they had seen.

Table 6.1 Stages in the Development of Seriation

Stage I Stage II Stage IIA Stage IIB Stage IIC Stage IID Stage IIE Stage III Stage IV

Ordination is not really attempted.

Understanding of relative size (e.g. bigness, smallness), but difficulty ordering more than three items.

Uncoordinated groupings of pairs containing large and small elements.

Uncoordinated groupings of triplets (e.g. one large, one mediumsized, and one small element).

Arrangement based on aligning the upper parts or tops of the rods without attention to the lower parts.

Arrangement of rods in an ascending fashion in resemblance to a “roof ” (or vice versa).

Successful seriation via trial and error learning, but limited to three to six rods.

Successful seriation via trial and error learning, but unable to add new elements without reconstructing the entire series.

Operational seriation: complete abstract comprehension of seriation with systematic ordering of elements and the ability to insert new elements into the series without delay.

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The children were tested for a second time, 8 months after the original presentation. They were not shown the model again, but drew from memory. Eight months was a long enough period for a child to be likely to move from one level of comprehension of seriation to a higher level.

As noted above, under Piaget’s model, the memory would consist of literally retained (“figural”) line contours, supported by an abstract understanding of the model. The memory image would be the result of these two interacting factors.

The results were dramatic. Eight months after seeing the model, the memory drawings (of the children who did recall the model) had either not changed, or had improved (in the sense of getting closer to displaying an ordered series). Twenty-two had advanced from a lower stage to a more advanced stage. Examples of the changes found are as follows: a child who had drawn a picture indicating no size discrimination might draw lines showing two size classes in the 8-month-delayed test. A child who had drawn three lines of increasing size, followed by another three lines beginning at the shortest again and increasing in size, might in the second test draw the whole series in order. But this child, in a test, would be unable to place a new physical rod in the series without placing it randomly and seeing if it looked right. Finally, a child who showed drawing seriation but could not pass the previous test after another 8 months, might show this ability, having fully achieved the seriation concept. The various patterns involved here are shown in Fig. 6.2.

An important point is that the improved but still lower-stage drawings did not look more like the actual model than the earlier drawings. That is, it was not literal, figurative memory that was strengthening. Improvement came from the developing comprehension of an ordered series. It came from a changing concept schema memory that had been entered into the original significate.

Piaget and his colleagues showed similar improvements in image recall in multiple other areas that involve the development of cognitive understanding.

Thus, memory images can be seen as involving an interaction between figural (literal, camera-like in that it is a copying function, but not cameralike in that perfect images are not retained) and construction based on an abstract understanding of what has been seen. This occurs from the first years of life. If there is some yet more primitive memory that is only figural, it has not been possible to go back to that point in an infant’s development.

Based on recent research, in any case, the age would have to be amazingly

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Stage III or IV

Stage IID

Stage IIA

Stage IIE

Stage IIB

Stage IIC

Stage I Figure 6.2 Developmental patterns of drawing seriation in children. Patterns of drawing seriation in children based on Piaget’s four stages in the development of seriation.

See Table 6.1 for a description of the stages.

young, perhaps birth to 2 months—and possibly with a memory function lasting only seconds.

CONTEXT AND CODING IN LONG-TERM MEMORY In the course of a long series of research into human memory for words, Endel Tulving found that the context in which word items were presented affected how they were coded in LTM (Tulving, 1966; Tulving & Osler, 1968; Tulving & Thomson, 1973). For instance, if experimental participants

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were thinking of the item BIRD within the context of spider-eating birds, the codes for BIRD were identifiably different from the codes representing the same animal but within the context of thinking about eagles.

Tulving endorsed the view that when we learn a list of words, or other content, a new complex of information is established in LTM. This contrasted with the earlier position that the long-established word items in long-term store were tagged with information corresponding to “present on List X” (see Chapter 2). The idea of a new-memory complex is now widely and perhaps universally accepted. Thus, if thinking of spider-eating birds, the individual would select “features” from the bird concept reflecting creatures of this kind, and enter these into the memory for the word item, while other bird features would not be included. (The new memory formed when an individual learned BIRD as part of an experiment would correspond to the memory significate for that item, in Piagetian terminology.)

The context, then, in which an item was presented influenced the codes of the relevant new memory.

Tulving’s position here conflicted with ideas that currently dominated the field. He came under some attack. The accepted view was that if you encountered, say, the item TREE on a list, TREE meant TREE, in any context whatever. It could not mean anything else.

It would be theoretically possible that when we memorize TREE on a word list, the corresponding memory is literally the word TREE (represented as here in visual, or else perhaps in auditory form). In fact this had been Ebbinghaus’s own view. But what Tulving had discovered, as had McGeoch before him, was that the primary code for a word such as TREE is not a copy of the percept TREE, but a code representing the meaning of the word (or, in Tulving’s view, some part of that meaning).

It is of interest that when we encounter a word to be learned, such as TREE, our cognition activates the semantic code for the word, and establishes this code as the memory.Yet, at recall the semantic information must be translated back into the appropriate word. Things are not as simple as they might appear.

When McGeoch (1942), through some ingenious experimentation, discovered the role of the semantic code here, he assumed that this form of representation was the code for words in human long-term store. It was also of some interest that McGeoch admitted he had no model for what a semantic (meaning) code might be. However, it clearly existed. Later, other researchers, unwilling to move quite so far from the Ebbinghausian view,

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established that there are also weaker sensory codes for the word items, that is, a memory of how they looked or sounded (Underwood, 1969).

However, the dominant—by far the strongest—code is semantic.

Tulving had discovered that the information in the relevant memories differed (depending on context) when he found that certain cues were successful in providing recall when, say, Context X had been present at learning, but these same cues were not successful when Context Y had been present at learning. Successful cues correspond to—or match—the content of a memory. His data meant that the memory significates were different under Context X as compared with Context Y.What was probably his most famous study involving this factor (as well as issues centered on recall and recognition) is described below.

Retrieval Cues Tulving and Thomson (1973) presented their experimental participants with cue-target pairs. The cues were weak associates of the targets.

“Associates” of words have been established by presenting a word, Word X, to a large number of people and asking them to recall the words that come to mind when they see Word X (Kucera & Francis, 1967).

A strong associate is a word that is often reported in this situation. For instance, BONE would be a strong associate of DOG. A weak associate is a word that is occasionally reported. For instance, BATH sometimes elicits the associate NEED, and BIRD sometimes elicits the associate SPIDER. Thus, in the present study, participants were presented with target items, linked to their weak associates, as in: Path—TREE Spider—BIRD Participants learned a list of words, presented in this fashion, to a criterion level in Stage 1 of the experiment. In Stage 2, a different experimental session, they were presented with strong associates of each target word. For instance, they were presented with the word EAGLE (a strong associate of BIRD). I will call these strong associates the Stage 2 list. They were then asked to look at each item in the Stage 2 list and provide the words that first came to mind (free associations) in response to these items.

In Stage 2, the free associate responses to EAGLE might be SOARS, TALONS, BEAK, MAJESTIC, BIRD, WINGS, GOLDEN, etc.

In Stage 3, participants were asked to look at the list of associates that they had provided, and determine whether they recognized any of these

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words as having been presented as a target during the learning session in Stage 1. A significant number of participants failed to recognize BIRD. In Stage 4, the original cues were provided to the participants and they were asked to attempt to recall the associated word that had been learned in Stage 1. Thus, “spider” would be presented as one of the cues. Many participants who failed to recognize BIRD in Stage 3 were able to recall BIRD in this final, cued act of recall.

In the study, these findings were roughly the same, across all stages, for the original target words.

The Divorce Hypothesis What had been shown by these data is that how an individual is thinking about a given item, at the time of learning, influences the nature of the semantic codes established to represent the learned item in LTM. Thinking about BIRD in the context of spiders (some small and medium-sized birds eat spiders) establishes one body of information. Thinking about BIRD within the context of an eagle, a large fierce creature, establishes a different body of information.

Tulving interpreted the data as follows. He suggested that any given word corresponds to a concept that contains an extended body of information. He labeled this information as involving “features” (e.g. the features of different birds). The context in which a target item is learned determines which features are coded into the new memory (the memory significate for that word item). Relevant features from the overall concept will be coded into the memory significate. Features in the concept that are not relevant will not be entered into the new memory.

Tulving’s research indicated that certain cues (those relevant to the context) can then elicit the memory, while other cues (those not relevant to the context) will fail. Under Tulving’s view, this outcome is due to the fact that only some of the conceptual features have been entered into the new memory, and only cues that correspond to those features will be helpful. Also, and critically, once the new memory has been formed, contact no longer exists between the background conceptual representations and the new memory. In other words, once a set of say small-bird features have been coded into the newly formed memory, the connection between that set of features and the permanent, background bird concept, is severed. I shall call this the divorce hypothesis.

Replications of Tulving’s data have been provided by a range of researchers (Dong, 1972; Fisher & Craik, 1977). However, focus has also

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been given to the predictions of the older, classic-associative model [as embodied in FRAN (Free Recall from an Associative Network) or ACTE (Adaptive Control of Thought version E)] and the present divorce hypothesis. Under the former view, all material in LTM is inter-associated, such that there would remain associative connections between the memory for a given item and all the relevant conceptual features (e.g. all features in the BIRD concept if BIRD had been memorized), including those not actively considered during learning. This is also the position supported by the Genevan model, and in the present book.

The question here reduces to the following. Could a “feature” of the relevant concept that was unlikely to have been thought of during learning, nonetheless operate as an effective cue? Because if this were the case, then the divorce hypothesis would fail to be supported.

The findings here have been that a cue that does correspond to something probably thought of during learning tends to be the most effective in eliciting the correct target, as Tulving had claimed. But cues that involved ideas that were probably not considered during learning will in some cases also elicit the target (e.g. “soars” for the original item BIRD presented as insect-BIRD).These latter cues are less effective and less reliable; but sometimes they work (Nelson & McEvoy, 2002).

Tulving’s divorce hypothesis can nonetheless be defended. For instance, it is not possible to know what items might be activated in an individual’s thoughts when he or she learns a list. If on occasion “soars” works as a cue even for an insect-eating bird, it is of course possible that the learner did think of how birds soar, during the time the list was being memorized. This would explain the occasional success of unlikely cues of this kind.

Chapter 9 provides an alternative explanation of these data, based on a non-divorce hypothesis.

How then can the data on cueing be explained?

A Genevan Explanation of Cueing Piaget did not address the role of cues within this or other contexts. One possibility under the Genevan view, however, is the following. Suppose a new memory significate is formed, and it involves a boat. The boat is relatively small. Thus, in the conceptual representation—the schema—providing the meaning of boat, the information relevant to this particular kind of boat becomes highly activated, and delineated. That is, the relevant information in the memory involves a small boat. But this body of information, centering on a small boat, is permanently associated, if only at weak or

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medium strength, with the overall boat schema. As a result, if some different aspect of the boat schema is contacted at the time of testing (e.g. by a cue such as “ocean liner”), spreading activation could lead to X, and an unlikely cue would then prove successful.

In addition, the relations obtaining between the boat schema and other information in LTM will also play a role. The more extended the relations, the better the chances of successful recall.

Some implications of the present hypothesis, and how it relates to certain critical aspects of representation, are pursued in Chapter 9.

Schema Integration and the Capacity of Working Memory A final brief note seems needed concerning the span of consciousness, or what in the mainstream literature is labeled working memory.

The capacity of working memory was established on the basis of our ability to recall a series of random items, and is well known as ranging from 5-9 with an average of slightly under 7 in the case, at least, of Americans and many Europeans (Miller, 1956). Piaget’s view here was that the capacity to maintain information in awareness depended on the strength of the schemas used to construct that information. Random items would therefore show a very weak memory span. In support of this view, it is known that when grammatical sentences are presented, the memory span jumps dramatically to something closer to 15-21 items.

Under the Genevan view, the more integrated the schemas in play support target information, the more this capacity will extend. Here it is posited that we could maintain much of the content of an event that has just unfolded, and maintain that content simultaneously; that is, if we wished to think directly about any well-coded aspect of this body of information, it would be instantly available, having been in the wings of consciousness (much like the end of a telephone number as we recite the beginning). The more integrated the operating schemas, the more information can be held in this state. Thus, here working memory does not have a fixed span.

An adequate test of the span, though, would need to involve the meaningful and interrelated content itself, and not random items, or even the last (unrelated) words of a series of sentences. But the latter has been the approach taken in the mainstream, leading to underestimations of the human capacity to maintain information “to be thought about.”

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CONCLUSIONS The model described in this chapter may seem to imply a level of complexity, concerning human recall that is beyond what could be achieved in the natural world, i.e. nothing like this under the moon. Certainly, in the past, the tradition has been rejected by quite a few due to this daunting quality.

The logic seemed to go: a thing as intricate as this, and with capacities like this, would have to be mystic. But today I think we are more tolerant of the idea of huge complexity here, possibly beyond our current understanding but not, hopefully, beyond understanding as such. At least I believe myself that models positing memory as a simple thing, working on the basis of very simple functions, are certain to be proved wrong.

CHAPTER

7

Altered Memories The present chapter examines the nature of memory content that has changed from its original form. Perhaps last year you saw a brown house with a garage attached to the left-hand side; perhaps now, with some reason to recall the building, you remember the house as white, with the garage not attached.

David Hume wrote that memories never change (Hume, 1739/1965, chap. 2): they are like pictures taken of the world outside. If the picture shows a brown house, that image cannot transmute into a different image.

The picture might fade and grow holes, but a brown house cannot turn white.

Psychologists worked primarily within this (empiricist/copier) tradition into at least the latter half of the twentieth century. Today it has been established that experienced memories do change. I know this all too well—having moved a large clock tower across a street, in recollection, and in fact altered a medium-sized house not too distant from the road to a small house tucked well down into a valley. The defense today of the original model is that memory content stored in long-term memory (LTM) does not change (other than to weaken). It shows no transmutations. However, as noted earlier, experienced memories can show alteration, when (accurate), retrieved memory content B is mistaken for the target memory content A. Again, under the empiricist view, this kind of error and change in awareness does occur, but the codes in LTM remain veridical.

ALTERATIONS IN EPISODIC MEMORY: THE MISINFORMATION EFFECT In the 1970s, Elizabeth Loftus and her colleagues provided evidence of changed memories, with this work being later extended both by Loftus and other researchers across a range of contexts (Christiaansen & Ochalek, 1983; Lampinen & Smith, 1995; Loftus, 1977, 1979a, 1997, 2004; Loftus, Altman, & Geballe, 1975; Loftus, Feldman, & Dashiell, 1995; Loftus & Hoffman, 1989; Schooler, Gerhard, & Loftus, 1986; Schreiber & Sergent, 1998; Tousignant, Hall, & Loftus, 1986; Tversky & Tuchin, 1989). Loftus’s Human Memory, http://dx.doi.org/10.1016/B978-0-12-408087-4.00007-4

© 2014 Elsevier Inc. All rights reserved.

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original research is well known and will only be mentioned briefly here.

Perhaps the most famous study involved a series of slides that included a traffic sign, such that half the participants saw a stop sign and half saw a yield sign (Loftus, Miller, & Burns, 1978). Participants were later asked a series of questions. In the “nonmisled” (control) condition, the questions provided no misleading suggestions. However, in the “misled” condition, participants were subtly misled. Here participants who had seen a stop sign received a question such as, “Did another car pass the red Datsun while it was stopped at the yield sign?” During the subsequent recognition test, pairs of slides were presented, of the yield and stop signs, with the requirement that the sign seen in the original slides be chosen.

The results were that 75% of the control, nonmisled participants recognized the correct sign, while only 41% of the misled participants did so.

The Empiricist View Under the traditional copier view, all memories retain their original codes.

This means that they cannot interact with one another. For instance, new, postevent information should not be able to change or even influence the original memory as coded in LTM. As noted in Chapter 5, the situation has often been viewed as involving separate sets or files. In the present case, the original slides would be stored in one file and the experimental session, in which some misleading information was presented, in another. These files were seen as bounded; again, the two should not be able to interact.

The Constructivist View Under a constructivist view, it is rather a bedrock property of the system that information, often gained across different episodes, does interact. At the time when a memory, say Memory X, is formed, much or all related background information will be activated, and some of this will routinely enter the memory itself, as against being simply associated with the memory (de Vega, 1995; Gernsbacher, Goldsmith, & Robertson, 1992; Haenggi, Kintsch, & Gernsbacher, 1995). In the same way, at the time of recall all information relevant to this target comes into play, including postevent information. A memory is then generated, based possibly on the entire body of available data.

The usual term, as noted in earlier chapters, is that the memory is reconstructed.

The experienced memory of the misled participants in the study described above had clearly changed. So, the battle was on. Had the nonconscious codes in memory been altered, or not? And if altered, in what way?

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Factors Influencing Memory Change The early research in this domain established some other important principles. Only a weak memory can be altered by misleading postevent (or other misleading) information. Strong memories cannot normally be shifted in this fashion (Greene, Flynn, & Loftus, 1982). Also, it was established that warning participants to the effect that some of the provided information might be untrustworthy slightly reduced the likelihood of the false content being recalled (Dodd & Bradshaw, 1980).

Memory change can also be effected for biographical events. Again, the events must be weakly coded; for example, information remote in time (Braun-LaTour, LaTour, Pickrell, & Loftus, 2004; Heaps & Nash, 2001; Hyman, Husband, & Billings, 1995; Lindsay, Hagen, Read, Wade, & Garry, 2004; Loftus, 1993; Loftus & Pickrell, 1995; Nourkova, Bernstein, & Loftus, 2004; Ost, Foster, Costall, & Bull, 2005; Porter, Yuille, & Lehman, 1999).

The studies have included both unusual and even dramatic events, such as an animal attack or almost drowning; they do not simply show distortions for trivial elements. And false memories can emerge with no experimental manipulation, as in the case of recollections of alien abduction (McNally, Clancy, & Barrett, 2004). Across the experimental studies, it is usually about 20-30% of participants who show altered memories. Such memories may emerge only after repeated testing for them (as against emerging on the first test), and there is also a pattern, once the false recollection is first generated, for the memory function to begin to reconstruct inaccurate details that were not originally suggested.

Even so, the act of reconstruction appears to include some properties that could be described as reflecting reason or logic. For instance, the function does not tolerate contradictory information. If the misled individual has coded both “a stop sign” and “a yield sign” as being present during the target event, some amalgam of the two (for instance, a stop-yield sign or the presence of two signs in the same location) will not be recalled. Only things known to be real or possible are reconstructed in the form of an experienced memory. But a situation involving some constituents that could (in reality) be mixed together provides a different outcome. Loftus (1977) again presented slides to her participants. In the slides, a green Datsun passed the scene of an accident; misled participants were exposed (again subtly) to the suggestion that the car had been blue. A subsequent recognition test resulted in some misled participants recalling the car as green, some as blue, but—most critically—some as blue-green. In contrast, the majority of the control group recalled it correctly as green.

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A further intriguing finding is that when participants are hypnotized, they become more vulnerable to the misinformation effect (Scoboria, Mazzoni, Kirsch, & Milling, 2002). The reason for this is not understood at present. However, it is known that good hypnotic subjects show severe impairment in reality testing of memories (Hilgard, 1965; McConkey, 1992; McConkey, Labelle, Bibb, & Bryant, 1990; Orne, 1962), and it may be that hypnosis diminishes the tendency to be strict about assessing memory content, including time-and-place information.

An important question regarding altered memories concerns whether the misinformation is simply remembered as a fact, without being embedded in the target episode (which would support the view of that misinformation being recalled from the wrong file), or whether it is recalled as an integral part of the target memory (Zaragoza, McCloskey, & Jamis, 1987).

Zaragoza and Lane (1994) found that both these outcomes can occur, with the embedded property being more common when their participants had answered questions about the target. Loftus and Pickrell (1995) reported that of their participants who recalled the false information, 32% remembered the information as being specifically encountered (embedded) in the slides, while others remembered that they had read about it during the second session, just felt it seemed familiar, or were guessing.

The Replacement Hypothesis for Memory Change: A Reexamination Probably, the most intuitive explanation of a changed memory is that the false information has replaced the true in LTM. This view was advanced by Loftus and Loftus (1980).The argument will be made here that the relevant memory significate has changed when an experienced memory changes, but that the events involved in this change are complex and do not reduce to a simple replacement hypothesis.

A critical factor with regard to testing memory, either on the basis of recognition or of recall, is that the test itself provides cues, and these may directly influence the condition of the memory in LTM. The standard testing procedure in the case of changed memories involves presenting the original, target item and the falsely suggested item in a forced choice recognition task. McCloskey and Zaragoza (1985) introduced a different approach, the modified test (MT). In studies of this kind the original, target item, such as a hammer, is presented (usually by being shown in a set of slides) and misinformation is given later, such as the suggestion that the object had been a wrench. In the MT, the target item is presented along

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with a new item (not the item that had been suggested in the misled condition). For instance, the recognition test might be between “hammer” and “pliers”. Under conditions of this kind, given a fairly standard form of (short) retention interval, the misled group performs as well as the control group (that has not been subjected to misinformation). This outcome has been replicated in other studies (Bonto & Payne, 1991; Loftus & Hoffman, 1989). McCloskey and Zaragoza took the data as indicating (1) that the misleading item had not replaced the target item in LTM, since the targets under the misled condition were still capable of being recalled and (2) that there had been no interaction between information in the misleading episode and information in the target episode.

What had been clearly demonstrated by these studies is that at the time of test, in the case of a short retention interval, both the target and the false (misleading) information are present in LTM. Again, the false item has not literally replaced the target item.

The Loftus and Loftus (1980) original suggestion had been that when a false item is recalled, the true item may be replaced in LTM. Under the MT, it was shown that replacement had not occurred. However, it should be noted that under the MT, the false item is not available as a response, and has not been retrieved. Thus, the fate of the true item when the false has indeed been selected, and recalled, remains uncertain.

Additional Factors in Altered Recall Two factors have widely been cited as possibly explaining altered (inaccurate) recall. Zaragoza and McCloskey (1989) suggested that the standard test data might be explained by guessing. For instance, participants who do not recall the target items will have to guess. In the misled condition, some may recall the misleading item, even though they do not recall the target.

So they will choose (guess) the misleading item in the test. Here, the false information has not changed the original memory in any way.

The other interpretation involves social compliance, or what has been called demand characteristics. Here, it is posited that the participants may recall the target, but also recall that the experimenter had mentioned a different item. They may decide to conform to the experimenter’s wishes, as they understand these wishes, by reporting the false item.

I am not going to pursue either of these issues further here. It has been shown that neither guessing nor social demands can explain the full extent of the misinformation effect (Belli, 1989; Belli, Lindsay, Gales, & McCarthy, 1994; Belli, Windschitl, McCarthy, & Winfrey, 1992; Chandler,

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1989; Lindsay, 1990; Payne, Toglia, & Anastasi, 1994; Schreiber & Sergent, 1998). A strong case has also been made against the social demands view by the findings, achieved through highly ingenious testing techniques, that 3-month-old babies (Rovee-Collier, Borza, Adler, & Boller, 1993), rats (Harper & Garry, 2000), and most notably pigeons (Schwartz, Meissner, Hoffman, Evans, & Frazier, 2004) also show the misinformation effect!

Time-of-Occurrence Information A critical point within the present area centers on identifying the episode in which an event occurred, or some information was learned. I’ll call this timeof-occurrence (TOC) information. When we have just lived through an episode, our memory for its content tends to be very good. But it has emerged that TOC recollection for details is often lost (or becomes nonusable) after quite a short period of time. For instance, if you are told in a coffee shop that you can find a shoemaker on Elm St., for a while you will remember where you learned this information, but perhaps a year later will still recall where the shoemaker works, but not where you first heard about him.

In the case of experimental participants who have been misled, it is critical that so long as the TOC information is still adequately coded in their memories, and can be used, they will recall the correct item. But if that code is weak, especially if it is weak for both experimental sessions, then the content in LTM will be something like “There was a stop sign; there was a yield sign,” without any means of differentiating when this information was acquired.

In conclusion, given that available TOC information (for the target session) almost ensures accurate recall, the fact that a significant number of participants select the false item means that usable information of this kind, at least for certain material (such as where the individual saw the true/ accurate item), has been lost, often within 20 minutes or so, although a great deal of general content (what happened in each session etc.) is retained.

MODELS OF EPISODIC MEMORY CONTENT It has been established that the contents of memory can be altered through a variety of factors, ranging from presenting misleading postevent information, to increasing vulnerability, to presenting misleading information through hypnosis or social compliance. These factors affecting memory alteration provide us with a framework with which to understand the nature of episodic memory and why its content can be changed. Such a

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framework is important because it enables us to propose models for the operation of episodic memory.

The Noninteractive Hypothesis In the present context, the position of nonconstructivists is that each episodic memory exists in a bounded set or file: it is separate from other memories.

Slides might have been shown in which a man picked up a hammer. This information would be coded in the set relevant to experimental Session 1.

In experimental Session 2, it might have been suggested that the item was a wrench. This information would be entered into a separate set coding for the events in Session 2. At the time of the test, participants would be asked a question such as, “In the slides, what did you see the man pick up: a wrench or a hammer?” The question, as a cue, would be capable of contacting both memory sets, since the question cue (“What did the man pick up?”) corresponds to information in both. Given that contradictory items are not normally recalled in human memory, the system must then select one item and reject the other. Now, under the independence/noninteractionist model the items in the two memories can be seen as competing to emerge.

Also, within the noninteractionist camp, it is widely believed that once an item is retrieved, this act of retrieval serves to block the other, competing, item or items, so making it even less likely that the competitor will be retrieved in future tests (Bekerian & Bowers, 1983). This interpretation is of course applied to other memory content, and not just to verbal items.

What is being suggested, then, is that when cues tap two different memories, the contacted information competes to be retrieved, with one constituent therefore being recalled, and the other not being recalled.

The content in LTM does not interact directly, under this hypothesis.

For instance, the material in Episode 2 does not provide interference with the material in Episode 1, nor does Episode 1 interfere with Episode 2.

Interference would imply direct interaction between the two bodies of information, an outcome that is prohibited by the present theory. This is a long-standing, nonconstructivist position; it might be called the traditional view within this context. The model is shown in Fig. 7.1.

The Interactive Hypothesis Chapter 5 provided a brief overview of the assumption of hierarchical structure in autobiographical memory. It is an assumption with strong empirical support. Under this view, higher-level content is associated via

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Long-Term Memory

Retrieved Information

Episode 1 CUE Episode 2

Episode 2

Figure 7.1 Model of the traditional (nonconstructivist) view of retrieval from LTM. Under the traditional view of retrieval from long-term memory (LTM), the memory content in LTM does not interact directly such that when a cue contacts two different memories (Episode 1 and Episode 2), there is no interference between these memories.

Rather, the contacted memories compete for retrieval, with only one of these memories being recalled (Episode 2).

subset links to the relevant lower-level content, and access to the latter can often be achieved by contacting the higher-level information and moving “down,” via the links, to the target. This is an effective process because the higher content is usually coded more strongly than the lower content, and so can be contacted more readily. In the type of study involved in the misinformation effect, the following structure can be assumed: Experimental Sessions Session 1: Seeing Slides Session 2: Reading Narrative Information in slides Information in narrative.

A hierarchical assumption underlies the body of material described below.

The previous section described the noninteractive hypothesis, according to which encountered episodes are stored in separate memory files. The alternative interactionist/constructivist approach posits that all information in LTM is capable of interaction, and does normally interact (within LTM).

In other words, the contents of different episodes are not isolated from one another, but instead show associative relations just as obtain within a single episode, and just as obtain between awareness and LTM. If different memories do not operate within separate, bounded sets, as posited above, then the present model needs to explain how the system

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distinguishes between such memories. How does the system establish that a given scene occurred, say, in Episode A and not Episode G? Here it is assumed that the critical factor is associated information. For a given episode, say going to the beach on Monday, the episode as a whole will be identified by associated TOC information: “This happened when we went to the beach.” One straightforward view concerning how an outcome of this kind can be achieved is to assume a header (Visit to the Beach) with subset links to all the content relevant to that visit, such that the links would automatically provide TOC information.

Thus, while an independence hypothesis posits that TOC data are provided by means of files (all information in a single file relates to a single episode), the present view posits that TOC content is provided by associative links, as also obtains with the general set of information in a memory.

Here there are no boundaries to the memory, and information within it can contact other information in LTM on the basis of the usual links (i.e. identity, similarity, temporal, subset relations, etc.)

As noted earlier, the same capacity, involving header and subset information, is present for any body of content identified in our cognition, including small sets such as “what happened when I got my feet wet.” It should be noted that bodies of material in LTM do not have a single header: any material that has subset information will operate in the same way.

A Subset-Relation Hypothesis It is posited in the present book that human memory is fundamentally geared to process information and, as noted above, all information within LTM is (1) capable of interaction and (2) geared to interact, based on the associative links described earlier. It is further assumed that content related to a header will be automatically subsumed under that header, either in all or in most cases. The origin of that content—where, in what episode, the information was acquired—makes no difference.

To restate: a header is simply some information under which other information is subsumed.

An Example Using Subset Links I might learn, for instance, that Gareth, the family dog, on finding himself near the ocean went into the water and enjoyed the waves. I may not have seen this myself, but was given the information in a vacation rental house.

Under the present view, my concept of Gareth can be seen as a header to which the new information concerning him will be automatically

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associated. That is, the Gareth-Family-Dog representation in LTM, if activated, has subset links to the body of information that I know concerning Gareth, which now includes his response to the ocean, such that my memory function could directly access this content (“downwards”) via the Gareth-Family-Dog representation. This means that if I were asked how he got on with the ocean, it would not be necessary for me to access my memory of being in the vacation rental house where a relative first told me that he had been unafraid of the sea; in other words, it would not be necessary for me to retrieve the target information from the rental house episode.

The present approach extends to the experimental work on changed memories in the following way. Suppose various individuals participated in two experimental sessions. In the first, they see slides that depict a man holding a hammer; in the second, they read a narrative in which it is suggested that the object was a wrench.

In Session 1, the participants in the study would see an individual holding a hammer, such that this content would be subsumed (as part of the relevant memory significate) under What Was Seen in the Slides. In Session 2, the misled condition, which involved reading the narrative, the participants would encounter the suggestion that the man had held a wrench. This would be subsumed under the Session 2, Reading Narrative header, supplying the information, “I read that the man held a wrench.” As noted above, information concerning the episode in which information is encountered involves associative links with the relevant headers, rather than the presence of the information in a distinct file.

The present assumption is that the input “The man in the slides held a wrench” would also be associated, when first encountered, with the “What was Seen in the Slides” header (since it is clearly information relating to what was seen in the slides). When the memory content is strongly coded, “I read this in the narrative” would also be associated with the Slides header. These TOC codes being weak, however, the latter datum would soon, in many cases, either be lost or weakened to the point of not being capable of being utilized. The significate for the Slides episode would then contain both items of information (hammer and wrench), with no means of distinguishing which was the correct item in response to, “What did you see in the slides?” At this point, the two contradictory items would again compete with each other at the time of retrieval, except that under the present model the Slides header would lead directly to the activation of both items (in other words, they exist in the same memory significate).

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Note that under this view, the memory significate for the Slides episode has changed; that is, the pattern of associative information in LTM has altered from the time when the Slides episode was originally coded. There has not been replacement of one item by the other, but the addition to the Wrench constituent of information directly subsumed under the header for that episode.

The Fate of Nonselected Items in Memory At the time of retrieval, the memory function will generate one of these items, and fail to generate the other (assuming that a response is given).

It is generally believed that the item that is more strongly coded will be “selected.” Many variables may influence the processes involved when one item is retrieved, and the other is not (some of these variables are examined below, and some in Chapter 8). The fate of the nonselected item is not currently known. It has been widely posited that it continues in its original state in LTM, but that it is “blocked” in some fashion by the retrieval of the successful competitor ( Bekerian & Bowers, 1983). An alternative view is that the codes for the nonretrieved item may be weakened in LTM. Under a consolidation model, for instance, the system engages in active processing to maintain content in the long-term store (McGaugh, 2000; Wixted, 2004). A nonselected item might enjoy less subsequent processing for maintenance than a selected item. At any rate, there is evidence that it is extremely difficult to recall the nonselected item once retrieval of its competitor has occurred (Loftus, 1979b).

A final theoretical point concerns the following. If a participant is asked, “What did you see when viewing the slides—a hammer or a wrench?”, which memory significate (the Slides session, or the Narrative session) is more likely to be tapped by these cues? The present model would suggest that access is more likely to be achieved first through the Slides header.This is the case because it corresponds directly to the question, and also because the header is at a higher level in the hierarchy of information, and thus more easily activated, than subset information. To access Session 2, it would be necessary to make contact with the information “you saw a wrench in the slides,” which is subset information. Thus, the chances are that for most participants the Slides session is contacted first, and the competition between items occurs under that header.

An interactionist model, including the Subset Association hypothesis, is shown in Fig. 7.2. Because a figure is involved, the LTM content is shown

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Cue

Long-Term Memory

Target Episode

Subset Links

Associated Episode A

Retrieved Information

Associated Episode B

Associated Episode C

Recollected Episode

Figure 7.2 Model of the interactionist view of retrieval from LTM. Under the interactionist view of retrieval from long-term memory (LTM), a cue contacts a target episode in LTM. Through subset links, episodes associated with the target episode become activated. Elements of these associated episodes can overlap because of shared subset information. An integrated episode, consisting of elements that are the most strongly associated with the target episode, is then retrieved from memory.

in a spatial format. But, as urged by John Anderson, it is important to remember that LTM does not have spatial organization. The factor that relates one representation to another, say A to B, is the type and strength of the link or links between them. Thus, information in a given memory significate, perhaps “What Happened on Morning X” is not stored “together” in a spatial sense: it is integrated on the basis of information specifying that any given event, say eating pancakes, happened on Morning X. It is also

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critical that the same subset information can be linked to multiple different headers, and of course the same header will by definition show subset relations to different constituents.

It is also not possible to show in the figure more than a small number of the vast network of links that would operate in these memories.

Another approach conceptualizes changes in memory that alter the patterns of association in LTM, due to loss of associative links over time, without directly positing that information relevant to a header is automatically associated with that header.

A given individual in the study described above may remember that she heard something about a wrench in one of the experimental sessions in which she participated, although she cannot recall whether it was the first (Slides) or second (Narrative) session.

Schank’s Model for Retrieval Under Schank’s (1982) model, the highest-level headers relevant to a given memory maintain direct links with all the subset content, including the more detailed, lower-level content. Here, Experimental Sessions would involve a subset link to Session 1, and to Session 2 (each of which would also be linked to its direct subset information), but also directly to “Hammer” and “Wrench” at the lower levels. (This assumption is also part of the Subset Association Hypothesis described above.) All this implies is that an individual might well remember that she encountered something about a wrench (or a hammer) in one of the experimental sessions. If, with time, the weak link between Session 1/Slides and hammer is lost, and the weak link between Session 2/Narrative and wrench is lost, the link to either or both of these items from Experimental Sessions may well still be functioning. Activity will then play through “down” from Experimental Sessions to the lower items, with the more highly activated item—in the present example, wrench—being retrieved.

Here, the pattern of associative connections in LTM has altered, due to the loss of some of the weaker links. And the experienced memory has also changed from the original (hammer) information.

It appears that the stronger an individual’s memory is in general, the lower the probability (to a modest extent) that misleading information will produce errors in recall. At the level of groups, elderly participants are more likely to be misled than younger participants (Rybash & HrubiBopp, 2000). A relationship has also been found between working memory

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capacity and the appearance of errors: the greater the measured working memory capacity, the less likely that an original memory will show change ( Jaschinski & Wentura, 2002). What appears to be involved here is variation among individuals in the endurance of T OC content.

VARIABLES THAT INFLUENCE THE SELECTION OF ONE CANDIDATE FOR RETRIEVAL OVER ANOTHER It was noted above that at the time of recall, two opposing items will compete for retrieval. The exact functions that determine the selection of one such candidate for recall over the other remain unclear. It is generally believed that the constituent that is most highly activated at the time of retrieval will be the constituent that is in fact retrieved. This view is also shared by almost all models of word-list recall (Brown, Preece, & Hulme, 2000; Burgess & Hitch, 1992; Estes, 1985, 1997; Glasspool, 2005; Houghton & Tipper, 1994). But what determines strength in this context?

Recency of Information in Memory Session 2, the misleading session, would have the advantage of recency. That recency plays a major role here was established in the early days of research into changed memories. Loftus et al. (1978), for instance, showed a strong misinformation effect when the misleading content was presented directly after the target episode and testing occurred after a short interval (20 minutes), while delayed testing (after 1 week) under these conditions actually eliminated the misleading effect.

Formation of Headers Session 1, in contrast, although lacking recency, would have the advantage of an entire body of information (what was seen in the slides) under an appropriate header. In most studies, this information was also centrally attended, as compared with just an insinuation, and not a direct statement, of some erroneous facts in the misleading session. (In fact one of the more interesting conclusions from the present body of research centers on the fact that casually presented, not centrally attended, information, almost encountered as a throwaway, seems to be reliably entered into LTM). And finally, the target First Session scene, at least if it involved slides, would have the advantage of the presence of visual images.

Other variables, not directly related to strength of coding, also influence the outcome here. They are examined in Chapter 8.

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Interference Effects Appendix B supplies an overview of our current knowledge concerning interference effects and cue overload, and also some material on consolidation. This material is relevant to the studies described below, and also to content in later chapters. If the reader is not immediately familiar with this information, the appendix should be read before the remaining sections of this and other chapters.

In a particularly intriguing study, Loftus (1979b, chap. 6) examined what happens when individuals are given the chance to correct a mistake in recollection. Here, participants in the misled group, who had recalled the false item, were told that their answer was incorrect, and given the chance to try again. They still could not recall the target item.

So it appeared that some process, possibly the retrieval of the false item, and possibly another factor, was preventing recall of the correct target, at least for a number of participants. But why should this be the case? In the example of a personal memory outlined in Chapter 5, I had first recalled Casablanca Airport as it had been on the day of our arrival. But, on realizing that this was the wrong episode, I was able to search again and to retrieve the correct scene from LTM. What then constitutes the difference between these two situations?

During the 1970s, researchers began to discover the powerful effects that can operate at the time a memory is retrieved. Output interference and cue-overload effects were established, among others. From that time on, I think it could be claimed that we have been in The Age of Retrieval: examples of interference tend to be explained on a retrieval basis only.

The position taken in the present book is that both encoding-based and retrieval-based interference operate in human memory, and that the kind of changes in memory content described here, within the context of the misinformation paradigm, are in major part the result of encoding interference.

This view contrasts with a widely supported belief that these effects are due to variables operating only at retrieval. Suppose participants, viewing a set of slides, saw a man pick up a hammer, and that under the misleading condition it was suggested that the item had been a wrench. Under a retrieval hypothesis, it could be posited that the fact of having retrieved WRENCH will strengthen the association between the operating cues and WRENCH, such that WRENCH would be more likely to be recalled again in subsequent tests. (As described in Appendix B, the retrieval of content from LTM strengthens that content; there is no debate over

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this.). But, under the present retrieval hypothesis, the fact of retrieving WRENCH will generate an output-interference effect on HAMMER, further diminishing the likelihood that HAMMER can subsequently be recalled (Bekerian & Bowers, 1983). This is seen as a blocking effect.

HAMMER is now being actively blocked from recall. Under this model, until WRENCH was retrieved, the HAMMER item had suffered no interference.

The available data, demonstrating retrieval interference effects, involve the following. When retrieval of multiple items from the same category in a long list occurs, such as say the names of flowers, retrieval of subsequent flower items is impaired (Battig & Montague, 1969; Slamecka, 1968, 1969).

And in the case of three or more rehearsals of a cue-item pair that differs from the target cue-item pair, such as for instance three rehearsals of FRUIT-ORANGE, then recall of the target, say FRUIT-BANANA will be impaired (Anderson, Bjork, & Bjork, 1994). But it has not to my knowledge been demonstrated that the recall of a single item (from the same category as the target item) will provide significant output interference. Thus, although the hypothesis—that this is the case—can be plausibly offered, there appear to be no outside data either to support or refute the claim.

The alternative view to a blocking hypothesis involves events that occur during the time of encoding and the period when the encoded items are held in LTM, as well as events that occur at the time of retrieval. Some background information, provided below, is needed to explore this view.

It was noted earlier that interference effects can occur when target items are exemplars of the same conceptual category (often described simply as similarity effects). This situation does obtain in the studies now under discussion. For instance, both HAMMER and WRENCH are exemplars of the higher-level concept TOOL. A particularly difficult paradigm for retention involves one that can be described as: A-B, A-D. In the case of words, this would imply the learning of responses to prompt items such as HOUSE to two different words HOUSE-CARROT, perhaps on List 1, and HOUSE-LANTERN on List 2. This arrangement produces high levels of interference. That is, responses in this paradigm are particularly hard to recall correctly. The interference involves the period of encoding and maintenance, in that no retrieval of, say, LANTERN is needed to produce impaired recall of CARROT. Also, the effect operates in the case of single-response recall; it does not require multiple exposure to other competing items (as is required for the retrieval effects described above).

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The A-B, A-D paradigm is present in the studies involving misinformation. Here the question, “What tool did the man hold in his hand?” has, under the misleading condition, two possible answers: Hammer and Wrench. It follows that if interference operates directly across the two episodes, as posited by an interaction theory, then the codes for the target item should be weakened by the presentation of the misleading item (and vice versa). Again, this weakening would occur during the period of encoding and of maintenance (prior to retrieval). For brevity’s sake, I am going to call this the period of consolidation.

Here it is posited that the coding of TOOL-hammer and the subsequent coding of TOOL-wrench corresponds to an A-B, A-D situation, just as would occur for HOUSE-carrot and HOUSE-lantern. Note that this effect has been demonstrated to occur under conditions in which retrieval interference is not implicated.

What then can be posited to occur in Session 1 of the misleading information study described here? Participants view a set of slides. The higherlevel information (the general sequence of events shown) should be retained by the time of the test, and longer. Again, higher-order information is more easily remembered than lower-order information. But there is an enormous amount of detail content in a series of slides or a video. No participant could be expected to recall every detail. In fact, some details may not be attended at all, and so not entered into LTM. Given the very large quantity of information presented once over a sequential period of time, significant interference effects would be expected, for details, within the slide-viewing period itself. (Interference can be assumed because if there were just one slide, showing perhaps a brown table with a blue tablemat and a book, participants would normally have no difficulty in recalling this information 20 minutes or an hour later, including the context in which they saw it.) In conclusion, the detail information relating the slides episode would be weakly coded. This is in some sense self-evident, in that misinformation effects are not obtained when the material is known to be strongly coded.

In Session 2, an item is encountered that conflicts with “hammer.”

Now the Tool-hammer, Tool-wrench situation (A-B, A-D) is established, if it is posited that the information from the two sessions interact during the period of consolidation. Thus, a principal interference effect should be functioning across that period. Since this effect, involving weakening of a target due to interference from only one competitor, has been shown to occur during the period of consolidation in the case of word-list items, there exist data that directly support this consolidation-interference

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assumption. Indeed, it is difficult to see why such interference would not occur in LTM during the period of item maintenance, given that it does occur in the case of list learning.

But these conclusions do not explain why recall of the incorrect item makes it extremely difficult, and often impossible, to next recall the target (if given a second chance at recall). One interpretation here could be the following: given that the target has already suffered interference effects during consolidation, a further weakening due to output interference from the incorrect item could move it below the threshold where recall is possible. Here it is posited that while output interference alone, of a single item, could probably not prevent subsequent recall of a target that had maintained its original coding strength, a target already weakened by the powerful effect of coding similarity (A-B, A-D) might simply be moved to a condition below the retrieval threshold.

Form of Memory Test Returning to the research into the fate of target items in the misled condition, it might seem that the MT has demonstrated that misleading information does not produce an interference effect (defined as a lessening of the ability to retrieve the target). In the MT paradigm, the misleading item is not presented as a choice for the test: a recognition test. Thus, if the target was Hammer, and the misleading item had been Wrench, the (recognition) test might involve Hammer and Pliers. In the studies by McCloskey and colleagues, under the MT recall of the target item by misled participants was as strong as the recall of the participants who had not been misled (McCloskey & Zaragoza, 1985; Zaragoza et al., 1987). It would appear, then, that the false item had created no interference effect on the target at the time of encoding.

However, an item that has suffered mild interference might even so be successfully recalled if other factors operate to strengthen it. In other words, under the misinformation condition HAMMER (target item) could have suffered some degree of interference, and yet still be the candidate most likely to be retrieved.

As noted previously, the form of a test can influence the status of items in LTM. If Hammer and Wrench are coded in LTM, and competing at recall, and the test offers Hammer again, this cue should contact (and so strengthen) the Hammer item in long-term store, while there is no Pliers item to be strengthened. Under these conditions, even if Hammer had been

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weakened, but still retains an adequate degree of strength for retrieval, it should successfully out-compete Pliers. Thus, a number of researchers have urged that the procedures used in the original MT experiments were not sufficiently sensitive to demonstrate an interference effect that might in fact have been operating (Belli, 1989; Belli, 1993; Chandler, 1991, 1992; Lindsay, 1990; Lindsay & Johnson, 1989).

The same argument holds for recall tests using the MT. In one such study, the original item was Coke and the misleading item was Peanuts.The test was formed as: “There was a soft drink can next to the keys on the desk.

What kind of soft drink?” Again, under this recall test the misled participants performed as well as the nonmisled (McCloskey & Zaragoza, 1985).

In this case, too, the test itself would be expected to influence the status of the target item in LTM. Given that both the target and misleading information had been assimilated to the memory significate for “what was seen in the slides,” with TOC information too weak to be used, then the following would occur. The content in the memory significate would now include three propositions: “There was a can of Coke,” “There was a can of Peanuts,” and “There was a soft drink” (and all this refers to one can).

Now, two sources of information support Coke, and only one supports the Peanuts. Under either a “selection,” cognitive model, or a higher-activation model, it is likely that Coke would be retrieved, even, again, if the original code had been slightly weakened.

Studies Examining Possible Consolidation-Based Interference Effects in the Misleading Postevent Paradigm Chandler (1989) presented slides showing various scenes, both in the first (target) session and in a misleading session in which a similar scene was presented. The pictures in this study were in fact highly similar. For instance, the same pond might be shown in both the target and misleading session, but with some feathers and dewdrops distinguishing one scene from another. In addition, under one experimental condition the misleading content was presented directly before the test. This would be expected to provide a strong recency effect for the misleading scene.

Under an MT (in which the correct target scene and a new scene, not presented during the misleading session, were offered for recognition), it emerged that misled participants showed significantly weaker recognition of the correct scene than control participants (who had never seen the misleading picture). Control recall here was 7% higher than misled recall.

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The study supported the view that a MT will show equal performance for misled and control subjects when the target material is coded at sufficient strength to match with the test cues, and be the strongest candidate for recall, as described above. But when the target involves particularly difficult material, and if the relevant codes have been weakened by misinformation, then the target will no longer provide a superior match to the cues. For instance, it is likely that when memory content slightly weakens, the higher-level codes can remain unaffected while lower-level details are lost. In notably similar scenes, the higher information (a pond, the shape of the pond) does not discriminate between the target and the alternative candidates, since these are all the same. It is the lower-level details (the distribution of feathers, etc.) that provide the ability to distinguish the correct target. If these are lost or weakened through an interference effect, then the correct target cannot be discriminated. Here, it appeared that a small interference effect was operating between the misleading picture and the target.

Other studies point in the same direction. In the original MT experiments described above, in which recall under the misled condition was as strong as recall under the control condition, there had been a relatively short retention interval between the presentation of the target item and the test. The target item could thus have been quite strongly coded, enjoying the benefit of recency. If it were not as strongly coded, however, it might fail to compete as successfully with the novel test item, such that any weakening due to interference might again become apparent.

Belli et al. (1992) first replicated the earlier MT data using a short retention interval. Here again, there was no difference between the ability of misled and nonmisled participants to recall the target (true) item. But when a long retention interval between the target episodes and the test was employed, there emerged a significant difference, just as in the standard testing paradigm. Now the misled participants were less able to recall the target items than the nonmisled participants. For both groups, the target item had been weakened by the longer retention interval, but some other variable was further weakening the codes for the target in the misled group. This was clearly the earlier presentation of the false item; thus, an interference effect was operating across the two episodic memories.

Several studies, also using the MT, reported impairment of the ability to recall target items in the misled group, but again only when long retention intervals for the target items were involved (Ceci, Ross, & Toglia, 1987; Toglia, Hembrooke, Ceci, & Ross, 1994). Belli (1989) provided further support for the impairment view (the view of interference within LTM

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between competing items) in the form of single-item tests. Here, the target item was presented alone and a novel item was presented alone, with the requirement in each case that the item be accepted or rejected as the target. It emerged that the presentation of the false item under the misleading condition had slightly but significantly impaired participants’ ability to recall the target (even though the misleading item was not presented as a candidate for retrieval). Similar findings have been provided by Chan, Thomas, and Bulevich (2009), Chandler (1991, 1992), and Frost (2000).

Other data further support the view that the target item can be impaired under conditions in which the misleading item is not recalled as an answer to the test question. Lindsay (1990) found that specific warnings that the constituent presented in Session 2 was incorrect led to the experimental participants being aware that this item should not be selected, and few of the misled participants did report it.Yet these misled participants still showed impaired memory (compared to the nonmisled group) for the correct target.

Schreiber and Sergent (1998) and Eakin, Schreiber, and Sergent-Marshall (2003), providing even more exact warnings and even offering specific cues as part of the warning, found that participants almost never reported the incorrect item, yet still showed impaired memory for the target.

CONCLUSIONS The models described in the present chapter offer two notably different stories concerning the nature of human memory. Under the first, as in Hume’s original approach, we experience the outside world in awareness and then hold that experience in the long-term store, unchanged from what was originally provided by the world, except for the frequent weakening or loss of this information. This is the noninteractionist position.

Under the second, memory is not geared simply to hold the experiences provided through our senses, but also—and more critically—to interpret them in the most effective way available. This involves, at least for an adult, the bringing into play of large bodies of information already stored in LTM, such that the “memory itself ” is not confined to direct experience. Here, extensive processing occurs outside of awareness, within the long-term store. Also, given the constructive and reconstructive nature of these functions, memory significates can change. It should be emphasized that these processes provide an adaptive and powerful interpretation of the world in most cases. But they can also lead to error—even if the error may be largely confined to details.

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The empirical evidence covered in this chapter makes, I believe, a good case for the interactionist position—for processing and changes within LTM itself. But it probably cannot be said that the argument for transmutation within LTM has been proved beyond question. Perhaps interference effects do operate directly between different episodic memories; however, the opposing position, with its emphasis on blocking of accurate, unchanged content, can also be maintained.

Under the traditional empiricist view, content in LTM might be seen almost as a piece of cloth with images painted on it. The cloth does not consist of dissociable components: it is a fixed body. As a result, if there are red roses to the right and white roses to the left, the red flowers can never turn white, nor can they swap positions. Given the view of nontransformation, the properties of memory could be seen as resembling the properties of the physical world—where (living) red roses do not indeed turn white.

Memories, however, involve information and not objects; this is perhaps the aspect of the debate that has proven the hardest to accept.

Chapter 8 continues the present topic with an examination of the dissociable (as against the whole-cloth) nature of memory, and of variables other than the memory content-itself that appear to influence retrieval.

CHAPTER

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Dissociative Memory, Variables that Influence Reconstruction, and Propositional Coding Under the constructivist model offered here, memory is not photographlike, particularly in the following way. If I walk along a city wharf and see a replica of a clipper sailing ship moored in the water, I should later be able to recall the appearance of the ship. I could probably also draw it from memory. But I had not memorized its appearance in the 2 or 3 minutes in which I walked past the clipper. I know what sailing ships look like, and after gaining a general impression of this particular exemplar I would be able to rely on my knowledge of such objects to recall a coherent image and even produce a (hopefully) recognizable picture. Human memory supports the passing impressions of daily life in this fashion; we could not retain the properties of all the objects we see as we walk about in the world if this required memorizing from the ground up.

An easy demonstration of the extent to which this is true can be provided if an equally complex, but wholly unfamiliar, stimulus is presented. As described in Chapter 6, the resulting memory images tend to be very poor, and in fact often unrecognizable as corresponding to the original object.

What this means, though, can be described as follows: it is the natural mode of human recall to fill in weak codes with already established information, and on occasion the function goes beyond “what must have been there” to generate inferences that are not accurate. (It may be the case, though, that there are constraints on this process.)

THE DISSOCIABLE NATURE OF MEMORY Memory can also be described as involving dissociative information. An abstract recollection consists of representations (ideas) connected together by relational properties. If I recall, “The fog was concentrated on the hill” (as a fact, not in terms of images), then a relational property, described in language as “was concentrated” has linked the representation “fog” to Human Memory, http://dx.doi.org/10.1016/B978-0-12-408087-4.00008-6

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a particular location. Under a dissociative model, though, these relations can change. If one weakens, an inference may come into play, and if fog is usually found in the valleys of that area, I might later misrecall what I had seen, remembering the fog as being in the valley. Thus, the components of a memory can be fitted and matched together in new patterns. Spatial relations are also dissociable, which explains why memory images often shift in orientation.

Unconscious Inference: Nickerson and Adams’s Study on Memory for Common Objects The empirical evidence in support of spatial relational change is strong. For instance, in a famous 1979 study conducted by Nickerson and Adams, participants were asked to draw the images on common coins (quarters, pennies etc.) from memory. A frequent error was to reorient the head shown on a coin to the opposite direction; for instance, Lincoln’s head, in fact facing to the right, would be drawn facing to the left. A favored nonconstructive interpretation of alterations in memory is of course that the recalled image is a true memory, but reflecting some other object seen in the past (source misattribution). But the idea that there exist other penny coins, in which Lincoln’s head faces left, can be excluded here. The original spatial relation had failed to be retained, and the system had inferred, and substituted, another.

Recent work has further begun to identify the locus of unconscious relational inference in the brain, with (not surprisingly) the hippocampus playing a major role (Reber, Leuchinger, Boesiger, & Henke, 2012).

Alterations in Memory for Syntactic Relations When events occur, our cognition interprets them on the basis of a wide range of abstract relations, which connect the target representations in an organization that supplies higher-order meaning, as in the fog on a hill example given above. Here, following the practice with propositional models, the term syntactic relations will be used.The evidence for syntactic alteration in memory is also quite strong. For instance, Wagenaar and Groeneweg (1990) interviewed internees from the Nazi concentration camp, Camp Erica, some 40 years after their incarceration. The study was of particular interest because the camp had been abandoned by the Germans in 1943, and the Dutch authorities had then interviewed the released prisoners.

Thus, there was an account of the camp dating from the time it had just been operating, and another account made many decades later. Wagenaar and Groeneweg found highly detailed and accurate recollection to be the

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most common pattern, although errors were also made. One such type of error involved syntactic relations among the participants in a given event.

For instance, Y might have attacked X (as established during the original interviews), but the 40-year-later memory of an observer of the event might be that X attacked Y. Here, the relations specifying the causal agent of the action, an individual toward whom the action had been directed, had weakened to the point of not being available, and a different set of relations been inferred.

A few years ago, I tested my recollection of a trip to New York that had occurred 6 months earlier. I had journaled the trip and, since I did not intend any subsequent testing, scored the results. On one leg of the trip back, I had been seated next to an unpleasant young man, arguably the worst such companion I have encountered. The details of the experience were correctly described in the 6-month recall test, except that I recalled having mistakenly taken the young man’s assigned seat when I first entered the plane. The journal revealed that in fact he had taken mine. Here, the syntactic relations corresponding to the agent of the action, X, (“X was in the wrong place”) had failed to be maintained.

Direct change in representations has also been widely documented. In the Wagenaar and Groeneweg (1990) study cited above, a question was asked concerning the hair color of a particularly brutal kapo at the camp.

Most of the ex-internees correctly recalled it as dark, but a few recalled it as fair. And in Stern’s (1904/1982) study of a casually attended event, the color of a visitor’s jacket was reported accurately by some of the participants, while others remembered colors that were not correct (although all would have been appropriate for a man’s jacket). The same range of memories occurred when these same participants recalled whether the visitor had a mustache or beard, or was clean shaven. The original memory codes here were weak, due to a lack of central attention, and various unconscious inferences apparently came into play.

Inference Versus Memory Replacement As described in Chapter 7 in the context of misinformation presented after a target event, it is generally posited that the two contradictory sets of information compete to be retrieved at the time of the test.This position is endorsed by nonconstructivists and constructivists alike. Under the view endorsed here, however, information relating to the target event (perhaps seeing some slides) would be associated with that event when the information was encountered, regardless of its source. The result would be two contradictory

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items operating within the same memory significate, and competing with one another for retrieval. In this case, there has been no replacement of one item with another; rather, both are maintained, and, assuming an answer is given to the test question, the reconstructive process will in the end result in one of them being recalled, while the other is not. If, however, an inference is made within the system, because the original information is too weak to be recalled, could this imply actual replacement within long-term memory (LTM) of the original code by the newly inferred code?

It is generally accepted today that the physical basis of a memory involves patterns of facilitated neural firing within LTM (Kandel & Squire, 2001). If the facilitation is so weak that it can never reach the threshold for retrieval, the argument could nonetheless be made that it is still there—it is a real pattern—in LTM, and has not been replaced. But equally, if it is assumed that with the passage of time all such facilitation is lost, then the code for the original relation (or representation) is not present in the memory significate, while the inferred code is present; it might then be said that literal replacement has occurred. If the facilitated neural patterns reflecting a memory do in fact vanish with time under certain conditions, then (in some cases) when we recall a brown house as white, or roses in a new location, the LTM codes have indeed altered. In the original memory significate, the house was coded as brown, and now, in the same significate, it is coded as white, with the brown representation no longer present.

RETRIEVABILITY OF MEMORY CONTENT: THE ROLE OF INFERENCE When two sets of information compete for retrieval, it is widely held that the content enjoying the strongest association with the operating cues will be retrieved (Anderson, Bjork, & Bjork, 1994; Bekerian & Bowers, 1983).

But other factors also influence the likelihood of retrieval. These same factors can be cited as influencing the probability that a given set of memory content will be retrieved even if it is not in competition with other content, and also our judgment as to whether a “memory,” presented from outside, is real or not.

Evaluative Processes in Retrieval As described earlier, one such factor involves the rejection of logically contradictory material, which appears to come into play during the process of reconstruction. We do not recall an object as being both a wrench and

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a hammer, even if certain content in LTM suggests both. A second factor involves plausibility. It appears that some kind of evaluative function, centered on plausibility and what might be called general reality testing, occurs prior to the retrieval of content from LTM. And as noted above, this factor also influences the likelihood of some content being accepted, or rejected, as an actual memory.

In a study conducted by Conway, Collins, Gathercole, and Anderson (1996), the first two authors kept journals across a period of time and were later presented with the true journal entries mixed with fabricated material.

In the case of entries that had been wholly fabricated, but involved highly plausible events (i.e. events that were likely to have occurred at that time), there was a 23% level of false recognition; that is, the authors felt that they remembered the event.

In some cases, though, instances of wholly plausible but false events were rejected. It is clear from data of this kind that, not surprisingly, human memory of actual episodic events includes information providing the knowledge that “this happened.” It is not known what form this information takes. It could in some cases be a simple strength factor, or it might also involve more specific content. The outcome of the Conway et al. study appears to suggest that the absence of content of this kind can sometimes enable the individual to identify a false memory even if it is highly plausible.Yet of course none of the false memories in the study enjoyed a “this happened” factor, and yet some were accepted. How the evaluation occurs, then, needs further clarification. But the presence of a form of realitytesting function is clearly evident.

In this same study, episodes that had occurred were generally identified as accurate. But this capacity appears to be deeply vulnerable to the passage of time, at least in some cases. Lindsay and Read (2006) selected participants who had kept journals over long periods. When the journals were read again after the passage of years, participants found that they did not recall many of the events described, even though at the time of their occurrence they had been considered important events. Here, even reading again about a given episode or person did not change the status of the memory; to the considerable surprise of the journal authors, it remained forgotten, as if it had never happened.

The work of inference appears at times to rely on an assessment of what is plausible (as against definitely known). McKoon and Ratcliff (1989) found that when participants were exposed to content that involved squeezing a fruit to make juice they tended to show a high false recognition

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for “orange” as the fruit. Anderson et al. (1976) presented sentences such as, “The animal shook hands with its paws.” The memory function is likely to “know” the kind of animal that is taught to shake hands, and have this confirmed by the fact that animal has paws, and so conclude that the creature was a dog. And when cues were given, it emerged that “dog” was a better cue than the original input, “animal.”

Certain other variables have been identified that may operate like the functions described above; in that, if they are present, we seem more likely to accept some given content as a true memory, and these may also lead to a greater likelihood of a given set of information in LTM being reconstructed, as against not being reconstructed. If Content X has been retrieved in the past, for instance, we are more likely to accept it as a true memory than would otherwise be the case, an outcome known as the illusion of truth (Ozubko & Fugelsang, 2011). The effect was first identified on the basis of repeated acts of recall (Arkes, Hackett, & Boehm, 1989; Bacon, 1979), but it can be found even after a single retrieval. A widely accepted explanation here is that retrieval increases the sense of familiarity (or “facilitation”) of the material, and familiarity tends to be assessed as implying truth (Jacoby, 1983). In a related pattern, our evaluation of the accuracy of returning content is influenced by the ease with which the content can be retrieved: the easier the act of recall the more likely we are to assume the content is accurate (Hawkins & Hoch, 1992). However, it isn’t clear at present whether a variable of this kind may also operate, like plausibility, to influence the likelihood of the same information being retrieved, as against not being “selected,” from LTM.

Memory as an Active Information Processing System Under the original empiricist model, the work of memory involves receiving information from the outside world and holding that information, unchanged, in the long-term store. But when the now very extended body of data concerning inference, the use of background knowledge, the avoidance of logical contradiction, and the role of reality testing is considered, the picture that emerges appears fundamentally different from a holding function. On hearing of an animal taught to shake hands, the system generates the idea of a dog; that idea, rather than the hazier notion of an animal, then comes to dominate the associated memory. The real picture is, again, of an active information-processing system geared to generate the most coherent, and so the most useful, understanding of the information that it encounters.

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Neurological Damage and Retrieval A striking insight into the role of reality-checking functions can be found in clinical studies of individuals suffering from damage to the frontal lobes.

Here, both the checks involving “this happened” and reality testing in general can be severely impaired (Baddeley & Wilson, 1986; Burgess & Shallice, 1996; Kopelman, Guinan, & Lewis, 1995; Moscovitch, 1989; Moscovitch & Melo, 1997; Parkin, 1987; Talland, Mendelson, Koz, & Aaron, 1965). In some cases, individuals recall entire events that never took place, although the events themselves are not bizarre. In other cases, the memories are bizarre. Within this context, Dalla Barba (1995) reported the case of a person who recalled that he had won a race and been given, as his prize, a steak, which he put on his knee. Other accounts include that of a man who had married recently but also claimed to have, with his new wife, several children in their twenties. When the difficulty with this view was pointed out, his explanation was that the children had been adopted (again, in their twenties). The generation of false memory content is identified by the term confabulation, and when individuals with frontal damage confabulate, the brain seems to be throwing up material almost at random, or at best under the impetus of loose similarity, and other, links. But no matter how strange the content, the content is accepted as an actual memory.

Extended Activation Within Long-Term Memory Concerning the disorganization of confabulated material, it appears likely that at any given moment in time multiple cues (both from the external world and from the individual’s thoughts) are operating to contact material in LTM. Further, the various links described earlier are known to come into play automatically between working memory and LTM; under the present model, they operate within LTM as well. (That is, if I think, “Did I ever see a fire ant?,” the now conscious representation “fire ant” will make contact with “fire ant” representations in LTM, and, under the present model, similarity, temporal, and other links, if present and strong enough, will play through from the LTM “fire ant” constituent to other content in the long-term store.) It is also the case that ambiguous stimuli will activate both (or multiple) meanings relevant to them, at a bottom-up level. Kintsch and Mross (1985), for instance, were able to show that if an item such as “mint” is presented in a sentence, both meanings of the word are activated at first, with activity reflecting the correct interpretation (as defined by the context) growing in strength as the sentence is understood, until it comes to dominate its competitor.

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What emerges is a picture of extended activation even at “low” levels of the content within LTM, which comes increasingly under the control of cues; the cues constrain the information to relevant material—overriding the irrelevant. This is of course a description of retrieval in the case of someone whose memory is functioning normally. In the case of frontal lobe damage, it appears that it is the higher-order levels (the constraining work of cues) that fails, with one or more (probably many) functions being impaired, such that the relatively random, uncontrolled associations operating at a lower level are permitted to emerge as memories.

Conway and Pleydell-Pearce (2000) have suggested that in the case of frontal lobe damage, what is revealed is the underlying set of the memory function to tailor memories to a particular goal: that of the acceptable selfimage. Here, it is assumed that with normal functioning, the system generally rejects “desirable” but unreal information, and that this capacity is lost under certain forms of brain damage, such that any generated (and, from the individual’s point of view, desirable) content is accepted as a memory. The position taken here is that the failure in normal recollection is more extensive than this, although the reality-checking capacity, which would in many cases reject untrue memory content, is certainly not functioning. It is also the case that while confabulated material can emerge in the form of a pleasing fantasy, this does not always happen. The material can simply be odd.

With regard to frontal lobe dysfunction, though, the important point under the present argument is again a picture of memory as involving complex, cognitive functioning, except that here the functions are impaired.

Obscure Content in Long-Term Memory: A Possible Role in Retrieval Under the present view, any datum relevant to understanding an event (or other content) is likely to come into play at the time of both memory encoding and retrieval. An interesting question concerns whether information that is obscure, in the sense of being weakly coded, and thus unlikely to be consciously recalled, can play a role here.

Suppose John and Anna are discussing memories of their high school, situated in a town that neither has seen for many years. John recalls that the road leading up from the low-lying school to Main St. had only a single pavement, placed on the right-hand side, such that students would always walk up the hill on the right. Anna agrees that the street had only one pavement, but recalls it on the left-hand side, with a similar memory of the students walking on the left.

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In fact, some years ago a decision had been made to provide only single pavements in that area of the town (due to restrictions of space), with a further requirement that the pavements consistently be situated on the right. John had heard of this when he was fourteen, but, at least at the moment, has no conscious memory of the fact. The information is still coded, although in his long-term store (such that strong cues might serve to retrieve it). Is it possible that this background knowledge may have played into his attempt to recall the orientation of the pavement?

The question will need to be resolved empirically. In theory, however, such obscure content might serve either to increase or decrease the likelihood of some given information being recalled.

To take another example from The War of the Ghosts, Bartlett reported that none of his participants recalled the line “Behold, I accompanied the ghosts, and we went to fight.” In classroom demonstrations involving this story, I found the same. Although, across the years, a few individuals did recall the line, it emerged as the least memorable of any statement in the passage. But why should this fairly clear fact—not part of the confusing battle scene—be so difficult to remember? One answer may be this: the passage contained repeated descriptions of the beings in the canoe (those whom the young man accompanied to the war) as “men” and as “warriors.” Since in both mainstream American and in British culture ghosts are not identified as men, and even people in stories do not participate in their activities, the repeated emphasis on what would have been understood as “live human being” may have weighed against the plausibility of a weakly coded statement, within LTM, to the effect that they were ghosts. Perhaps the statement therefore failed to be reconstructed.

THREE POINTS CONCERNING HUMAN RECALL In this section I would like to introduce three points, concerning human recall.

The Memory-Forcing Effect The first involves what might be called a memory-forcing effect. The most accurate recollection of a weak memory is likely to occur when the individual simply decides to recall this target, but is subject to no additional pressure. In contrast, when even as mild a further stimulus as questions are involved, errors tend to increase. Stern (1904/1982) for instance, in his

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study cited above, found that errors doubled under a condition in which he posed questions, as against offering a free recall task.

As is well known today, if it is suggested repeatedly that a certain remote event occurred, and the individual is asked to imagine it—thus generating imagery for the event—and if this exercise is repeated, the result can be the construction of an entire false memory or false scene (Hyman, Husband, & Billings, 1995; Loftus & Ketcham, 1994). Here, the memory function is being forced to an extreme degree. (It should be noted that not all individuals generate false recollections under these conditions, but the possibility is there, particularly it seems under conditions of emotional distress.)

When hypnotized and asked to retrieve a given memory, subjects frequently show some improvement in recall as compared to their performance when not hypnotized, but may also report a body of content that is inaccurate. Stalnaker and Riddle (1932), for instance, tested their participants’ recall of Longfellow’s poem “The Village Blacksmith,” and found both increased accurate recall and an increase in errors. Showing the same pattern, Perry, Laurence, D’Eon, and Tallant (1988) and Nash (1987) found that when subjects are age-regressed under hypnosis, they tend to recall a mixture of fact and fantasy. According to one interpretation of the hypnotic state, the retrieval function pushes particularly hard to reconstruct a target memory, thus opening itself to a high level of inaccurate reconstruction. This tendency is increased by the fact that reality testing is largely suspended, such that false content is not rejected (Orne, 1962; Stuss, 1992).

In support of this view, Whitehouse, Dinges, Orne, and Orne (1988) compared recall between a group of hypnotized subjects and a nonhypnotized group that had been told that they must respond to all the questions by making up an answer in those cases where they could not recall the original content. The two groups performed at the same level, except that those who had been hypnotized were confident in their answers; members of the nonhypnotized group, of course, were not.

In the case of good hypnotic subjects (but, again, not all individuals), suggestions provided in the hypnotic state can lead to “memories” of a false scene or event that cannot be distinguished from true memories, even when the individual is no longer hypnotized (Hilgard, 1965; McConkey, 1992; Sheehan, Statham, Jamieson, & Ferguson, 1991). Here, the retrieval function appears to have been forced to an extreme degree.

It can be concluded that inference in human memory does not operate in a fixed way. That is, there does not seem to be a kind of standard

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boundary condition that holds in every case (with some individual differences). Instead, the degree to which the function of retrieval is “pushed� can alter the extent to which inference comes into play, and perhaps also the tendency to accept retrieved material as a true memory.

Strong Memories With Weak Details: A Paradox for the Validity of Recollection Some memories appear particularly strong. For instance, a given episode may be retained across many years and perhaps for life, while tens of hundreds of others have been forgotten.

A memory of this kind does not imply that every detail will be accurate, however. The recollection as a whole may be a true recollection, but this does not exclude the possibility of an occasional inferred, inaccurate detail or details. This seems worth mentioning because some researchers and perhaps laypersons appear to lean toward rejecting a memory if they discover some element in it that is not accurate.

Neisser (1982, chap. 4) described a personal memory dating from his fourteenth year. He had been listening to a baseball game on the radio and the broadcast was interrupted with news of the bombing of Pearl Harbor.

But it occurred to him in middle age that baseball games are not broadcast in December. His conclusion was that what had appeared to be a clear, flashbulb memory of a startling event was in fact false. Under the present view, though, even if no further clarification of the episode had become available, the inaccurate recall of a detail (baseball game) should not be considered evidence that the entire recollection was invalid.

Clarification was provided, however. Thompson and Cowan (1986) were struck by an interview heard of the National Public Radio Morning Report, in which commentator Red Barber noted that it was ironic that the Army Navy game was scheduled to be played on the anniversary of the bombing of Pearl Harbor. He added that on that same day, years back, he had been covering a game between the Giants and the Dodgers, which at that time were the names of two football teams. He had heard about the bombing at half time. Neisser’s inference, presumably developed some while after he heard the broadcast, was thus a reasonable one; in spite of the incorrect detail, the memory was apparently accurate.

This episode is interesting for another reason. Neisser had remembered hearing a baseball game on the radio, but did not mention the names of the teams. He may not have recalled them, but they were clearly present in his LTM, in that they influenced the work of memory reconstruction. This

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is an example of content that is not available for retrieval but which can nonetheless influence the material that is retrieved—a possibility discussed earlier.

Constraints on the Function of Inferential Reconstruction In the tests of my recollection of vacations, measured against the original journal entries, a scene that involves source misattribution (confusing one episode with another) could of course reflect any level of the autobiographical hierarchy introduced in Chapter 5 (emotional tone, themes, periods of life, episodes, scenes, and details). But almost every example of inferred content operated at the level of detail, with a few extending one step up to scenes. In short, the inferences involved material right at the bottom of the hierarchy. Thus, in the episode recounted in Chapter 5, I recalled a jumbo Cadbury’s bar as a jumbo Crunchie bar, and a young man as an old man.

These memories involved events that had occurred when I was an adult, while it appears likely that the greatest changes in our recollections involve episodes dating back to early childhood. Also, the journal material centered on vacations, and as such in most cases these were not deeply emotional events, another possible source of heightened error. And there was no “forcing” of the memories. So this kind of content is probably not much prone to change over time. Even so, if the data here are found to generalize to memories of this type (not deeply emotional and formed in adulthood), then the finding that some 95% of inferred, inaccurate content involves this level of detail, and rarely anything higher, is an outcome worth noting. It was mentioned above that there may be some constraints on the function of inference; what appears to be operating here is some constraint to the lowest levels of the hierarchy.

PROPOSITIONAL CODING The processing structures described up to now have involved functions that provide movement from one body of information to another. An identity structure can provide movement from material in working memory to the corresponding information in LTM: if you are asked, “Did you watch the Easter parade?” this will access a possible “Easter parade” recollection. If you see a striking red flower in a store this may remind you of some red lilies you had displayed a while back in your living room: a similarity link.

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But these, in a sense, global links will not provide the needed associations “within” either a body of episodic content or a body of linguistic information such as speech or prose. Considering episodes first, a memory may include perceptual images but will also involve a large body of abstract information (Brewer, 1986, 1999). If Jane went on a hike last summer, she may recall the following: “It was a long hike, longer than I had anticipated.

The three couples who hiked began to be spread out along the trail, and at one point I was concerned because the trail seemed to fork and I did not know which was the right path. At that time, no one else was with me,” and so on.

There may have been imagery present in Jane’s recollection, but much of the information is abstract. Clearly the various aspects of the memory must be integrated together, such that they form a coherent body of information expressed in the above passage. The propositional model has application here to Jane’s understanding of the original event (as against her description of it). But what processing structures achieve this?

Parallels with Language One theory within this domain is that the organization of our thoughts, and of abstract memories, reflects basically the same underlying organization as human language. The formal rules that govern the linkage of concepts in language have been studied for centuries, and as a result could provide an extensive foundation for this new hypothesis. The posited, language-like, codes are identified as propositional codes, and demonstrate the following properties.

A proposition can be characterized as a unit of information, in thought or memory. Many propositions are integrated in our cognition to form more extended content. Propositions consist of concepts, related to other concepts on the basis of syntactic functions. The latter provide the particular role that the concept plays, with regard to how it connects to other concepts in the proposition. Two major types of structure can be identified here (and there are of course many others). In the first, there is an active entity of some kind: an “agent” that performs an action. Then there is the action performed. Finally, there is an entity that is acted on. In English, these constituents would be described as the subject, verb, and object of a sentence, with the underlying function (the type of link to the other constituents) being supplied by word order; for example, “The dog chased the cow” conveys a different meaning from “The cow chased the dog.”

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In propositional models, the abstract information corresponding to, for instance, “agent,” is supplied by a syntactic function (a processing structure) that “picks up” information concerning the agent in perhaps an actual life episode, and appropriately relates this entity to the other information in the mental proposition. If I notice that a man just posted a letter, the “man” representation will be connected with the activity of posting and the letter as the “thing acted on”, in my understanding of this small event. The second major type of higher-order syntax in propositional models involves an entity that is described, as in, “The rose was red.”

A proposition is generally defined as a basic unit of higher-order information that cannot be broken down into two smaller units or “facts.” Thus, “The dog chased the cow” would consist of one proposition, while “The dog chased the brown cow” would be considered as two propositions: “The dog chased the cow,” and “The cow was brown.”

The syntactic relations that operate in language involve complex forms, and the same complexity can be posited for propositional thought.

Thus, propositions can be related to one another causally, with a cognitive syntactic structure corresponding to the relation “because.” Or a multitude of spatial and temporal relations can be provided by a cognitive syntax corresponding to prepositions in language. Other syntactic forms can set the stage for time information, (the equivalent of the word item “when”), or indicate that some entity was given an object by some other entity. Thus, syntactic functions, indicating relational roles among the elements of a thought (or memory) provide the “links” that combine the various individual concepts together into a whole that embodies higher-order meaning. Under the model presented here, these syntactic “links” are processing structures that identify and code for the appropriate relations in the understanding of an unfolding event, or in the process of thought.

It was noted above that propositional descriptions can handle the events that occur during a life episode. It might seem a strange form of circularity to say that they can also code for the meanings carried in language, since the theory itself derives from language syntax. But what is posited here is that the thought being expressed in words has a certain propositional structure, which is to some degree mirrored by the language forms.

Difficulties were encountered, however, in the development of propositional models, with the assumption that our thought would directly correspond to linguistic grammar. For instance, it can occur that two different “deep” grammatical structures can operate to express exactly the same

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thought. The intuition of the early theorists was that the same meaning would involve the same cognitive syntax; the reason why language does not always operate in this way remains obscure. In view of these concerns, Fillmore (1968) developed a case grammar, which identified the invariant roles played by linguistic syntax, such that the same meaning would invariably be expressed in the same fashion. Later propositional models have typically employed one form or another of a case grammar.

Two well-known propositional models of representation in the field of memory were developed by Anderson (1983a, 1983b) and Kintsch (1974, 1992, 1998), and pursued by Kintsch and van Dijk (1978) and Kintsch and Buschke (1969). These propositional approaches have proven effective at representing abstract content of various kinds, related both to memory and to human thought. The approach is also identified with certain theoretical claims concerning the nature of the constituents involved in propositional representation.

Two Types of Codes for Representing Thought One form of representation deployed by humans—and computers— involves what is today almost universally called a symbol. A symbol is an arbitrary designator. By “arbitrary” is meant that a symbol stands for, and so represents, something, but shows no relationship with the “something” designated. Words are symbols. CAT does not resemble the actual animal we call a cat, nor display any cat-like properties. It is posited within the present tradition that the constituents involved in propositional thought (both in the case of concepts and of syntactic functions) are symbols. These are sometimes conceived of as states of the brain; that is, a brain in a particular state (neurons perhaps playing through in a certain pattern) could be the symbol for the animal, cat. Critically, it is not generally believed within the cognitive field that these symbols are words; they are rather cognitive elements of some kind. (It should perhaps be noted that Piaget used the term “sign” to designate the entity called “symbol” in the mainstream field, retaining “symbol” for a form of representation that does involve some inherent connection with the thing that it represents.)

One of the difficulties with a symbolic model of representation involves the question of why a certain arbitrary state of the brain would mean, say, “cat,” while another would mean, say, “water.” What would determine the associated meanings, since the symbol itself does not incorporate any specific content? This has led a minority of theorists back to the early rationalist position in philosophy: the view that the meanings of cognitive

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symbols are determined innately (Fodor, 1975). But the problems with this position are extensive.

A second form of code involves analog representation. Here, there is again an entity that represents something, but in this case the designator does share some properties in common with the thing designated. A map, for instance, is an analog representation of spatial properties; longer lines on the map designate longer distances in the space being represented. In human cognition, perception involves various analog properties. If we see an object, X, to the right of Object Y in the visual field, this is because Object X is to the right of Object Y in the world outside. If a balloon is inflated, perception will directly show its growing size, corresponding to the growing size of the actual balloon. Although a vigorous debate occurred across the 1970s and 1980s between those who believed that perception involves analog codes and others, such as Pylyshyn (1981), who urged that the codes that provide vision were symbolic, the issue has now been settled: we do generate images, and images involve analog representation (Kosslyn, 1994, 2005, 2006). The debate was always puzzling, in that symbolic codes are an extremely inefficient method of representing visual information, while analog codes are extremely efficient; the presence of analog representation in awareness is, for most of us, a moment-by-moment reality. Both mental and memory images—analog forms of representation—clearly exist.

Many researchers today favor the view that abstract/semantic conceptual representation (and so all abstract representation in memories) consists of symbolic codes, both at the level of awareness and “all the way down.”

This position is compatible with the view that analog codes providing for instance visual images also exist; that is, semantic (abstract) and perceptual information are of two different kinds. With regard to abstract representation being wholly symbolic “all the way down,” however, alternative views have also been developed, notably by Piaget himself. The issue will be covered in Chapter 10.

Propositional representation and propositional thought are terms often used today simply to indicate a human capacity for abstract cognition, using symbolic codes. Propositional thinking is reasonably posited to be efficient, since symbols are clear-cut entities that lend themselves to lawful manipulation. In other words, they are good for the purpose of reasoning. At any rate, issues involving propositional thought have now extended into new domains. There has been, for instance, a long debate concerning such basic aspects of “memory” as classic and operant conditioning. Under one view, conditioning is an automatic and unconscious process in which certain

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forms of stimulation will produce certain forms of response, due strictly to neural paths leading (although in a complex fashion) to the activation of specific muscles. And this is certainly the nature of conditioning in the case of lower animals, such as the famous and quite easily conditioned sea snail, Aplysia (Squire & Kandel, 1999). Under a second view, however, in the case of humans, even conditioned responses involve awareness and thought (Lovibond & Shanks, 2002; Mitchell, DeHouwer, & Lovibond, 2009). Under this view, controlled reasoning processes are necessary for any form of learning: contiguity of stimuli (as between a bell and food) is not enough. The reasoning processes here involve propositional thought, implying the establishment of beliefs expressed in propositional form (e.g.

“When a buzzer sounds, a light will follow”).

Data have been established that support both views: i.e. that of automatic responses with no beliefs involved; and that of the essential role, even in conditioning, of conscious belief. Perruchet (1985) found that when a tone was either followed by an air puff or no air puff, human participants would begin to expect an air puff if none had occurred in the previous four trials. The belief was there, but the participants did not produce a conditioned response if no air puff occurred on the fifth trial, thus supporting the view of an automatic process not driven by belief. But there is also evidence that if participants have incorrect beliefs concerning the relationship between one event and another (as with tone and air puff, or bell and food), then their “conditioned” responses tend to correspond to their beliefs rather than the actual sequence of events (Parton & Denike, 1966).

For our present purposes, though, the important point concerning propositional models is that they supply an adequate theory of the processing structures that can interpret and code for an event, and those that underlie our comprehension of the meanings provided in language. Even so, just how symbolic representation may operate in all this is a topic for another chapter.

CHAPTER

9

Memory and Emotion In the introduction to this book, I described a memory dating to the time just before my ninth birthday. It is among the most vivid of my life; it is also a detailed memory. As noted earlier, the level of detail extended to the number of the room in which I stayed at a hotel on our arrival in Morocco.

The episode was one of deep emotional engagement. I found this new world exciting and wonderful, and full of color. I believe this is why I have retained such a clear recollection of that long episode. At any rate, the case for a heightened memory capacity due to emotion will be made below.

Are the extended episodes that I recall from that time accurate, or fully accurate? I have no way of determining this. An older sister has been able to confirm a range of the events, but does not remember some of them; moreover, certain of the most vivid moments occurred when I was alone (making friends with a dog, or discovering an empty beach near the house we had rented).

With regard to the variables that can enhance our ability to recollect some incident or other material, rehearsal (or the reinstatement of content in any form) appears to be universally accepted. The second factor, under the view offered here, involves the schemas that construct memories: the more extended and integrated these background schemas are, the better the target information will be retained. (The issue of schema integration will be covered in Chapter 10.) The third factor is affect.

THE EFFECT OF EMOTION ON RECALL Bartlett (1932) advanced the thesis that an emotional event will be better retained than a neutral event. And of course this conforms to daily human experience. Who does not remember the period of time when he or she fell in love, or recall a tragedy that has befallen their family? Yet when it comes to experimental psychology, there has been extensive research into this issue in only two areas. In contrast, parallel work within the physiological domain has been extensive. Even within the former context, though, the emerging data seem clear.

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Many years back, Yerkes and Dodson (1908), working with mice, advanced the thesis that increased “arousal” heightens the memory function up to a point, but that when the arousal grows too intense, the memory becomes impaired. The term arousal has the advantage of being neutral, but perhaps the disadvantage of ambiguity. If an animal experiences a foot shock associated with learning, it can be taken that the animal’s arousal increases; but does it feel anxiety or fear? Most researchers working with animals in natural settings report that their subjects are, in fact, emotional creatures (Darwin, 1872/1998; Lorenz, 1963). Under this view, extremely strong, negative, emotion would be expected to disrupt the memory function. Still, it has been suggested that the Yerkes-Dodson Law should be abandoned, since it cannot be put to an empirical test and may by false (Christiansen, 1992).

There exists a large body of data today indicating that moderate and strong emotion improves memory (Bluck & Li, 2001; Brewer, 1988; Linton & Melin, 1982). Emotion also tends to enhance the vividness of episodic recollections, in the case of both positive and negative affect (Reisberg, Heuer, McLean, & O’Shaughnessy, 1988; Rubin & Kozin, 1984). And there is evidence that we can retain accurate and detailed recollections even of highly stressful events (Reisberg & Heuer, 2004). At the far end of the continuum here, though, when the level of stress becomes intolerable, such that the individual suffers emotional trauma, memory tends to be impaired, and impaired in multiple ways (McNally, Clancy, & Barrett, 2004). Thus, human performance does appear to correspond with the Yerkes-Dodson position, if it is allowed that the stress needs to be extremely high, at least in some cases, before the memory function is affected.

It is important within this context to distinguish between a poor, disrupted, or fragmented, capacity for recall, and amnesia as such. In the case of amnesia, nothing is remembered. There are cases on record in which extreme shock or stress has produced actual amnesia (Arrigo & Pezdek, 1997). But such cases, now widely attributed to biochemical reactions in the brain that disrupt the consolidation process, are rare. The typical outcome for a traumatized individual is to remember that horrifying events had occurred and their general nature, although the memories can lack the organizing frames characteristic of normal human recall (Janet, 1904).

Memory for Stressful Events With regard to our capacity to recall stressful events, researchers have examined memories formed by people who have witnessed a crime. The data have been mixed: in some cases, the recollections are quite detailed and

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accurate, while in others they are weaker than would be expected in the case of an emotionally neutral episode (Hosch & Bothwell, 1990; Kuehn, 1974;Yuille & Tollestrup, 1992). One of the difficulties here is that given the same frightening external circumstances, some individuals may not cross the threshold into extreme anxiety, while others may.

A second approach to the issue of strong emotion involves presenting a film or slides to experimental participants, with two different versions of the material. At some point in the presentation, one version shows a sudden, shocking scene, while the other shows an equivalent but neutral scene. Probably the best known of these is the surgeon/mechanic paradigm first developed by Heuer and Reisberg (1990), in which a boy goes to visit with his father. In one version, the father is a doctor and the boy is exposed to a grisly situation involving graphic surgery; in the other the father is a mechanic and the boy sees some difficult auto repair. The findings have been that the emotional scenes produce superior recall of the central, important information, but weaker recall of the peripheral information, as compared to a control condition in which no strongly emotional scenes were present. By “peripheral� here is meant content unrelated to the scene involving emotional shock. This occurs whether the peripheral material is shown centrally, or as background detail (Burke, Heuer, & Reisberg, 1992; Wessel & Merckelbach, 1997, 1998). In the same way, details that relate to the central (emotion-inducing) event are well recalled even if they are seen in the background of the film or slides, as against being presented centrally.

While the majority of studies indicate enhancement of memory for emotional content or emotional events, some have not. Baddeley (1972) conducted a study in which servicemen were given detailed instructions concerning a (simulated) emergency. One group believed the emergency to be real, and this group exhibited weaker memory for the instructions.

Kramer, Buckhout, Fox, Widman, and Tusche (1991) reported that their participants showed weaker memory for graphic, upsetting images than for neutral images. And Kramer (1984) reported that the victims of violent crimes, such as rape or assault, recalled fewer details concerning the attacker than did the victims of less violent crimes, such as robberies.

With regard to the Baddeley study, however, a distinction can perhaps be made between the effect of trying to process important instructions, where anxiety about following the content could be a factor, and living through a life episode in which events need to be understood but detailed instructions do not have to be followed. And the Kramer (1984) study is

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likely to have involved events capable of producing fear at a traumatic level, where disruption of memory can be expected.

In contrast to the data reported above, Christiansen and Hubinette (1993) and Hosch and Bothwell (1990) found superior recall for victims of a crime as compared to bystanders. And Yuille and Tollestrup (1992) reported that witnesses to murder showed a very strong memory function, extending to accurate recall of details.

Attentional Factors in Eyewitness Memory: The Phenomenon of Weapon Focus It was noted above that when a violent or shocking scene is encountered, material related to that scene is recalled at a superior level, while nonrelated details are more weakly recalled than under a control condition (in which no shocking element was present). A perhaps more extreme example of this involves the phenomenon known as weapon focus. In the case of individuals who are present at a crime scene, if a gun is shown, the subsequent memory appears to fix overwhelmingly on this source of danger, such that other, even important, details may not be recalled (Loftus, Loftus, & Messo, 1987; Stanny & Johnson, 2000; Steblay, 1992). The question has been raised as to whether the effect is due to attention (all attention being given to the gun), as against emotion in and of itself. At present, the data indicate that both factors are involved (Kramer, Buckhout, & Eugenio, 1990; Maass & Köhnken, 1989; Peters, 1988).

Thematically Based Emotional Memories As described above, there has been an extensive body of research involving sudden exposure to a troubling scene or a particularly troubling object. A consistent finding here is that the memory function is heightened for that single, focusing element at the cost of other details. Reisberg and Heuer (2004) noted, however, that the majority of highly emotional events in the course of our lives are probably not of this kind; that is, they don’t involve sudden, visually presented, shocking scenes (although of course something like this can occur). Most powerful emotional events do not center on a single constituent—an image of some kind—but rather a situation, one with many associations and a personal frame, in some cases continuing through time. Happiness or grief is usually involved, in a matrix of extended information. Given these large differences, the effects on memory of what Reisberg and Heuer identify as a thematic source of emotion (as against an unexpected shocking stimulus) could show a pattern unlike that found in the research described above.

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For thematic emotion, there would usually not be a single, brief moment into which the emotion would be focused. It appears likely that memory could be enhanced for much of the surrounding context of the relevant theme, both cognitive and physical. Thus, if memories characterized by strong affect do tend to be of this latter type, a rich field of research remains to be opened. Relevant to this issue, Laney, Heuer, and Reisberg (2005) asked their participants to recall emotional events from their lives, and the reported events were coded as either thematically induced, or as induced by a visual stimulus. In one student population, the thematic memories constituted 82% of the whole, while in another population, involving a wider range of subjects in age and educational background, the number was 71%.

Laney, in an unpublished study, derived stories in which either a troubling emotional situation was slowly unfolded, or in which the events remained emotionally neutral. The former situation could be seen as corresponding to a range of thematically based emotional memories in daily life.

The findings were that the emotional story was retained significantly better than the neutral, but—in contrast to the data on sudden visual impact— both central and peripheral details showed the enhancement effect.

All the research described above, though, involves participants experiencing emotion in a diluted form. An individual may read a moving story and respond with some degree of feeling, but a story or series of pictures can (in most cases) only induce a relatively mild affective response, which does not begin to approach the impact of the powerful emotional events that we experience, at one point or another, across our own lives.

In autobiographical recall, content high in the hierarchical organization is retained better than content that is low in the hierarchy. But in some cases a low-level constituent is remembered well, even across long periods of time, these constituting the “special elements” described in Chapter 5, or what my student identified as “gems.” A well-known example here concerns Conway’s record of an experimental participant who remembered “dancing with Angela” (a relatively low-level constituent) on a particular evening (Conway, 1995).

EMOTION AND MEMORY IN EVERYDAY LIFE A database of facts has been established concerning emotional memories.

Negative and positive memories appear to show the same pattern of focusing on central as against peripheral elements in the case of sudden, disturbing visual stimuli. Issues have also been raised as to whether physiological

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arousal (for instance, such as would result from exercise) could have similar enhancing effects on recall, but the data so far indicate that this is not the case (Libkuman, Nichols-Whitehead, Griffith, & Thomas, 1999).

Heuer and Reisberg’s Study on Emotion and Rehearsal It could be urged that emotional response is not the real causal factor in strengthening memory, but that emotion leads the individual to rehearse or think about the relevant content more than would obtain with neutral memories. In response to this issue, Heuer and Reisberg (1990) compared memory performance under four separate conditions. These involved watching either an emotional or a neutral set of slides, watching the neutral version with instructions to memorize the material (thus encouraging rehearsal), or watching the neutral version for a particular event, to examine the effects of close scrutiny. The emotion group displayed a significantly higher memory function than the three others. As will be seen later, research involving animal studies in which emotion-simulating drugs are provided at moderate levels subsequent to learning also leads to enhanced memory performance, an effect that in the case of animal subjects obviously cannot be explained by rehearsal (McGaugh, 2000).

Emotion and Goals Another variable that has been explored within the context of memory and emotion is that of goals. With regard to goals as such, theory in this area has taken two major, differing forms. Under the first, advocated by Schank and Abelson (1977) and Schank (1982, 1999), virtually all of our activities across the day are motivated by goals. We might have the goal of going to work, then of performing activities relevant to that work, and so on—constantly. Further, under this model we possess extended bodies of knowledge (memory organization packages), which provide information concerning the ways in which a goal can be achieved. Thus, our goals determine the information that is retrieved from long-term memory (LTM) on an ongoing basis, throughout each day. This function provides not only knowledge of what we need to do, at any given moment, but also anticipation of the relevant events (we expect scheduled trains to stop, etc.) and the ability to read the behavior of other people as they, too, pursue their goals. The theory further includes some intriguing possibilities concerning the role of causal relations in human memory, encompassing physical, social, and psychological domains. These large bodies of knowledge can be understood as

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constituting a major part of the higher-order schemas that operate when we form and retrieve memories, and the model (run as a successful computer simulation) is probably the most detailed account of these schemas to be developed up to the present time. It is not concerned, however, with the role of emotion.

The other approach to the issue centers on the view that the strength of memory codes, and the reasons for success or failure in recalling a memory, is fundamentally controlled by our goals and, more precisely, the emotions associated with them (Barsalou, 1988; Markus & Nurius, 1986; McAdams, Diamond, de St. Aubin, & Mansfield, 1997; Sheldon & Elliot, 1999; Singer & Salovey, 1999). As mentioned above, a popular form of this approach posits that the most critical goals center on the individual’s selfimage. Here the desired self-image is seen as controlling autobiographical retrieval in general; it can be understood literally as the control process for human recall (Conway, 1992; Conway & Pleydell-Pearce, 2000). Further, if a deeply desired goal is achieved, this will provide an accessible, vivid memory; the same may occur if there is failure to achieve a goal of this kind, due to the corresponding distress. Here goal achievement (or failure) normally provides a memory that will endure. If, in contrast, the failure is very deeply felt, the episode may (under the Conway model) be inhibited from the process of retrieval.

Critically, the role of the self-image is seen here as the basic function controlling the work of autobiographical recollection.

This view is not endorsed in the present book. Achieving goals, as such, occurs repeatedly across a typical day, and clearly does not, in and of itself, lead to enduring memories. If the goal relates to a major aspect of the individual’s self-image, then success or failure is likely to lead to distinct emotion, which is seen here as the causal factor relating to the memory function; that is, emotion provides the real explanation of why events that involve success or failure related to the self are so well remembered.

Under the present view, while the self-image can be important, it is just one among many factors capable of eliciting strong affect, and is not the bedrock function that controls human recollection.

Emotion and Early Memories In further support of the present emotion hypothesis endorsed here, it has been established that the first memories of life (usually very brief, “fragment” scenes) are typically characterized by distinct affect (Dudycha &

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Dudycha, 1933; Waldfogel, 1948). Freud (1916–1917) claimed that human memory is weak across the first years of life, but that strong emotion can significantly strengthen its capacity, to the point even of providing permanent recall. Of course, Freud thought that the emotion here was invariably traumatic (with the trauma, however, being often generated through ideas rather than external events). In contrast, most researchers today who support an emotion hypothesis would hold that either positive or negative affect can have this same effect. Also, in studies involving the first years of life, the reported emotion varies between positive and negative. In a study at SUNY Oneonta, participants recalled their two earliest memories, as best these could be identified, and parents were asked to provide an account when possible of the same event, without having heard or read the report of the participant. It was found both that the majority of the memories were accurate and that positive recollections were confirmed at as high a level as negative recollections (Howes, Siegel, & Brown, 1993). Of course, parental input was possible for only a subset of the memories. It should be noted, though, that the earliest recalled moments of life are not called “fragment memories” for nothing; they are often very brief, such that there is not a great deal of content that might provide inaccurate detail. For instance, one participant recalled seeing a snake under her bed.This was the entirety of the recollection. Her mother confirmed the episode, noting that the participant had been badly frightened. However, the snake was a toy.

A strong case can be made that these small events or scenes are retained from the beginning years because, in most cases, they involved emotion. It needs to be remembered that small children can be subject to very strong emotional reactions, often to stimuli that would produce no reaction in the adult. And sometimes the stimuli are wholly perceptual; the simple appearance of something, often involving color, may strike a child forcefully (Bruner, Goodnow, & Austin, 1956). In the Howes et al. study, a handful of memories consisted of no more than the participant looking at something, or seeing something, with no other content. One individual recalled a floor that consisted of white, green, and orange squares. Her mother confirmed that the family had once lived (during the first years of the participant’s life) in a house in which the kitchen floor consisted of a pattern of white and green squares: but no orange. However, this was clearly not a false memory, given the correspondence of green and white, and geometric shape, with the original floor. It seems that an extra color had been somehow inserted into the image. Here the memory, perhaps prompted by emotion,

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is enduring (in all probability, permanent) and basically accurate, but also contains an edge of inferred content.

As noted above, some researchers hold that the presence of emotion, typically reported in earliest memories, does not in and of itself explain the long life of these recollections (Neisser & Harsch, 1992), but rather that the emotional quality of the experience leads to rehearsal of the scene or event, such that rehearsal is in fact the true causal agent in overcoming infantile amnesia—across a period when the individual is amnesic for most happenings. My own view is that rehearsal on the part of a 3-year-old child would not have an effect so powerful that it would stamp a memory into LTM for life. Human memory is weak in infancy, strengthening across childhood until late adolescence or perhaps the earliest adult years. At the age of three, it is still weak within the context of episodic recall or general information recall. (In contrast, it is of course very powerful when it comes to the acquisition of words and grammar.) But the idea that hearing her family talk about some event, or perhaps her own thinking about the event, would lead to its recollection some 15 or 70 years later, seems unlikely.

Also, memories of this kind (the color of a floor) are probably not the type to provide extended discussion. Other recollections included knocking over a cup of juice, playing in some puddles, driving past horses, seeing some kind of large (possibly barn) door, and picking up pieces of broken china in a garden.

Flashbulb Memories Another area of research concerning emotion and recall involves the phenomenon known as flashbulb memories. In 1899, Colgrove reported a study in which 179 participants were asked to describe their recollections of the moment when they heard of President Lincoln’s death, 33 years earlier. A striking finding was the extent to which these individuals remembered where they had been (context) when the news came. A typical response was, “I was setting out a rose bush by the door. My husband came in the yard and told me.” This participant was 79 years old.

Brown and Kulik (1977) pursued the issue further, positing that unexpected news carrying very strong emotion might produce an atypical form of memory. They tested their participants concerning recall of the moment they had heard of the assassinations of various prominent figures, and also moments of shock based on personal news. President Kennedy’s death, in particular, elicited memories of context (in all but one participant), and

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sometimes the recollection of trivial sensory details present at the time. A colleague of Brown’s, for instance, remembered that when he had heard the news he was walking up some steps at his college, and he could still recall the particular feeling of the steps under his feet 13 years later.

With regard to context, of course we often recall the context of where we heard some news, for a period of time. But normally this form of recollection does not last long: Larson (1992) found that, in his own case, context information for nonemotional news was at chance level after 2 months.

Certainly it is not retained for the 30 years recorded in Colgrove’s data.

A large number of studies were conducted following the Brown and Kulik article, but these often involved the individual hearing of some public disaster or some good or bad news, having an emotional reaction, and either recalling or misrecalling the relevant context after a relatively short period of time, ranging from 6 months to 3 years, but not decades (Bohannon, 1988; Christiansen & Engelberg, 1999; Lee & Brown, 2003; Neisser & Harsch, 1992; Schmolck, Buffalo, & Squire, 2000; Wright, 1993).

It was noted later by some researchers that these studies might not involve actual flashbulb memories. We hear of disasters on an almost daily basis, and an emotional response to news of this kind will not normally provide the same intense impact as that involved in the murder of a U.S. president. Also, the very long-term retention of context had not been measured. A further issue here is that in the case even of striking disasters, such as the loss of the Challenger space shuttle, some individuals may respond with flashbulb memories and others may not, such that the data would reflect a mixture of, possibly, two different kinds of recollection (Gaskell & Wright, 1997).

Brown and Kulik had explicitly noted that flashbulb memories were not photograph-like, in that many details of the context scene weren’t recalled later. They had coined the term flashbulb because of the peculiar property of the memory function catching some trivial sensory element, as if a flashbulb (focusing on some small aspect of the scene) had gone off. There was no implication, though, of retention being like a photograph. It has been widely claimed that flashbulb memories are highly detailed (which might imply a photograph-like process). But it is not clear that the data support this view. Kulik, for instance, remembered the context in which he had heard of Kennedy’s death (13 years after the event), of his teacher crying; however, he did not recall either her hairstyle or her dress. It is hard to see how this could be interpreted as a detailed recollection.

The idea that flashbulb memories include a great deal of information concerning context may have been generated because some completely

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trivial, sensory content is sometimes retained; the assumption might be that if stimuli as unimportant as the feeling of the steps under your feet, or the pattern of marks on a wall, are remembered, then surely more important imagery would also be remembered. But this is precisely what does not happen with flashbulb recollection.

A final claim made by Brown and Kulik was that flashbulb memories appear to have so great an impact that the content that is retained across time may be strictly accurate, (enabled by a kind of “Now print!” mechanism). Most researchers today believe that this claim has not been supported (Schmolck et al., 2000). A difficulty with interpretation here, though, is that the data showing inaccuracy in context recall may have involved memories that were not of the flashbulb type, as described above.

When Bohannon and Symons (1992) examined their participants’ memories of the Challenger disaster, they found that individuals who reported high levels of distress showed significantly more accurate recall of context information than individuals who reported low levels of distress, after a period of 3 years (location at 93% for the high-distress group, and at 18% for low distress group). In addition, Er (2003) tested participants who had been present in the 1999 Marmara earthquake for their recall of the event, and found 100% correct recall of their location after a year, while those who had only heard about the quake showed significantly poorer recall.

Still, it might be expected that victims of such a frightening event would retain information concerning it for at least a year, even if no flashbulb effect were present.

Under the view advocated in the present book, given that all memory content involves inference (even if the inference is normally accurate), and the belief that emotional memories are more subject to change than neutral memories, it still seems unlikely that flashbulb recollection would be strictly accurate, in all cases, across extended periods of time. The outcome might be something more like my student’s memory of a white, green, and orange floor, when the original floor had been only white and green.

An extremely important finding in the Bohannon and Symons (1992) study was that the high-distress individuals recalled the context information over time at a higher level than they recalled the semantic information (i.e. what they had actually heard concerning the Challenger disaster). This enhancement of peripheral over central information reverses the normal pattern of adult episodic recall.

Some researchers today hold that flashbulb memories are simply emotional memories, and as such do not differ from other emotional memories.

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But a case can be made that flashbulb phenomena in fact involve an unusual kind of affect-driven recall. In the experimental studies outlined above, in which emotional content seen in slides was compared with neutral content, participants in the emotional condition recalled the central, “important” information at a relatively high level, but recalled peripheral details poorly. Yet one of the striking properties of flashbulb memories involves the arguably permanent recollection, in some cases, of a few wholly trivial, peripheral details (the feeling of steps under your feet). The argument was made earlier that thematic memories might well include a wider range of happenstance information, associated with a strongly emotional event. But this posited effect also differs from the arbitrary but very strong recollection of just a few, random, sensory details—indeed as if a flashbulb had gone off, but involving a strangely narrow focus.

In short, it is possible that flashbulb memories constitute an unusual form of memory that requires a distinct kind of impact, and that changes the usual patterns seen in the case of both neutral and (most) emotional recollections. The change is that they can, perhaps in their more extreme forms, “stamp in” memory for general context, and also hold and retain random sensory details. Yet the data seem to indicate that recall of the central, important information is not enhanced (note the Bohannon and Symons article described above). This is particularly significant, in that the standard pattern, even in emotional memories, is that important information tends to be retained at a higher level than trivial information. In this, flashbulb memories appear particularly unusual.

Memories of Traumatic Experiences Memories of events proven to be traumatic necessarily reflect situations in which extreme stress and anxiety are in play, and the memory function might be expected to decline.

Severely traumatic memories, involving what is known today as posttraumatic stress disorder (PTSD), also show the characteristic of retaining imagery in an unusual way (Janet, 1904, 1911; van der Kolk, 1996). The memories of trauma are characterized by a higher level of sensory content than obtains in nontraumatic memories. In the most extreme cases, what returns to the individual may consist of images without the normal abstract/semantic information that would structure such memories (e.g. aspects of order, temporal awareness, and causality). Here, the remembered content is necessarily disorganized, and characterized by gaps (Sargent & Slater, 1941, p. 760).

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There exists physiological evidence that memories of trauma show different patterns of brain activity from neutral memories. Rauch, Savage, Alpert, Fischman, and Jenike (1997) found increased right hemisphere activity, related to visual and affective coding, when veterans read a written record of traumatizing events that they had experienced. There was also decreased activity in brain areas associated with speech production.

It has also been found that the content of the intrusive memories that characterize PTSD in general, although basically accurate (involving traumatic events that did occur) can contain inaccurate, nightmarish elements and inaccurate details (Frankel, 1994; McCurdy, 1918). As mentioned earlier, powerful emotion may increase the tendency to infer content. Thus, there appears to be some link between certain kinds of very strong affect and the retention of imagery at an unusual level, with the presence of some distortion also implicated. Another characteristic is the extreme longevity of traumatic memories: they have been described as indelible. It may even be the case that flashbulb phenomena operate at the very mild, weak beginning of this continuum, showing similar properties to PTSD (long life of the memory and heightened sensory content) in a diluted form.

It was noted earlier that under the Yerkes-Dodson Law high levels of stress would impair the ability to remember something learned, or an experienced event. But the issue becomes complex within the domain of human recall. Traumatized individuals have difficulty in acquiring and remembering new general information, and every student probably knows that high anxiety (far short of trauma) can impair the ability to do well in an examination. But memory for general, deliberately learned content can be distinguished from the memory of experienced events. Rubin, Feldman, and Beckham (2004) tested veterans diagnosed with PTSD for their recollection of the episodes that had proved traumatizing, and found that the gaps and disorganization reported in many earlier studies were not present; the participants here remembered the target events well. The implication may be that the level of stress needs to be very high indeed before episodic memory is significantly impaired. The veterans in this study did, however, show the heightened sensory content characteristic of traumatic memories, and marked emotional reactions.

A final point is that traumatic memories endure, and indeed are so strong that they push into awareness even when attempts are being made to exclude them (Krystal, Southwick, & Charney, 1995). Thus, in the most severe cases, what emerges is a partial amnesia for the critical events and a diminished level of abstract structure, but also the capacity and tendency to

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retain the memory vividly, if in truncated form, for decades, and probably for life. Full amnesia for the traumatizing events is, in contrast, rare. The pattern of recall also fails to support the notion of a psychological defense mechanism, since the troubling aspects of the memories are retained. As mentioned earlier, this has led many researchers to believe that the weaknesses shown in the case of traumatic memories is probably due to the effects of stress on biochemical mechanisms in the hippocampus, and possibly other sites, leading to disruption of the consolidation process (Payne, Nadel, Britton, & Jacobs, 2004).

THE PHYSIOLOGICAL BASIS OF MEMORIES CHARACTERIZED BY EMOTION It has been established for several decades that declarative memories are consolidated and stored in the medial temporal lobes of the brain, with these functions centering on the hippocampus and its overlying cortical structures, and the diencephalon (Parkin, 1987; Scoville & Milner, 1957). The term declarative memory refers to the type of memory covered in the present book: information that can be retrieved into awareness.

Nondeclarative memory, in contrast, involves conditioning, habit forming, and implicit memory, as well as motor, perceptual, and possibly cognitive, skills (Eichenbaum & Cohen, 2001; Schacter & Tulving, 1994). Declarative memories that date back for long periods of time appear to be stored in additional locations, perhaps the prefrontal lobes, although probably still with some engagement of the hippocampus.

The Role of the Amygdala in Emotional Memories The amygdala, a structure located close to the hippocampus, has been found not to be involved in memory storage in either monkeys or humans (Baxter & Murray, 2000; LeDoux, 2000). However, in both these groups, the amygdala influences emotional responses, and in the case of humans these structures modulate the consolidation and ongoing storage of emotional content in the hippocampus. Activation of the amygdalae in response to some event or other information has been shown to influence activity in the hippocampus (and other regions), resulting in enhanced memory function (Anderson & Phelps, 2001; Buchanan & Adolphs, 2004; Canli, Zhao, Brewer, Gabrieli, & Cahill, 2000; Gold & van Buskirk, 1975; LeDoux, 2000; McGaugh, 2000, 2004; Ă–hman & Mineka, 2001; Roozendaal, 2000; Weiskranz, 1956; Zola-Morgan, Squire, Alvarez-Royo, & Clower, 1991).

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The amygdalae exhibit close associative connections with many other structures, including the hypothalamus, brain stem arousal centers, and basal forebrain. There are also bidirectional associations within the neocortex (Packard & Teather, 1998; Pitkänen & Amaral, 1994). In addition, the amygdalae receive sensory input both on a rapid, and on a slower, more complex, basis, thus providing the possibility of both quick and more nuanced responses (Amaral, Price, Pitkänen, & Carmichael, 1992; LeDoux 2000). Both body and brain react to emotional stimuli, and it is believed that multiple structures are involved in a kind of extended network, with the amygdalae playing a central role, probably also in multiple stages.

Studies of brain activity have further supported the claims made above.

Using positron emission tomography, Cahill, Babinsky, Markowitsch, and McGaugh (1995) showed that the higher the activation of neurons in the amygdala, the stronger the retention of emotional content, while this same neural activation showed no relation to the retention of neutral content.

Some gender differences have been found in response to emotional stimuli. In the case of female participants, emotional as against neutral stimuli led to increased activation in the amygdala and the frontal cortex, while male participants showed only increased left amygdalic activity (Cahill et al., 2001). Both groups, however, reported the same subjective emotional reaction, implying that any differences in the memory function were due to events involved in the consolidation of the target material, rather than the immediate experience of that material.

It might be thought that individual words could carry so little affect that no significant influence on memory would emerge when “emotional” verbal items were compared with neutral verbal items. But significant effects have in fact been found. There is typically no difference between the recall of emotional and neutral words under immediate testing; however, emotional words are recalled better after a delay. It is also the case that although negative items are recognized more slowly under immediate testing, this effect reverses after a week (Kleinsmith & Kaplan, 1964).

Based on the majority of studies, emotional pictures (such as a mutilated face) are also recognized significantly better than neutral pictures, and the same is true for images depicted in slides or videos. These patterns obtain for individuals who have not suffered any form of brain damage.

However, a disorder known as Urbach-Wiethe disease causes bilateral deterioration of the amygdala (deterioration in both the left and right hemispheres). Herpes simplex encephalitis, caused by assault from a virus, can also damage the amygdala. A range of studies have shown that when

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control subjects (with intact amygdalic function) and individuals who have suffered bilateral damage to the amygdala are exposed to emotional and neutral stimuli, such as pictures or slide shows, the emotional stimuli are better retained than the neutral for control subjects, but there is no difference between the two in the case of the subjects with amygdalic damage (Adolphs, Cahill, Schul, & Babinsky, 1997; Hamann, Ely, Grafton, & Kilts, 1999; Markowitsch et al., 1994; Tranel & Hyman, 1990). Asked about subjective experience, one individual with amygdalic damage reported feeling emotion upon exposure to the stimuli, but this effect did not transfer to the enhancement of subsequent recall or recognition. The pattern differs in the case of partially amnesic subjects, where there has been damage to the hippocampus (involved in memory consolidation and storage), but not to the amygdala: here, recall of both kinds of material is lower than occurs in the control group, but emotional input is still remembered better than neutral (Hamann, Cahill, McGaugh, & Squire, 1997).

Blocking of the relevant receptors in the amygdala also eliminates the enhancement of memory for emotional content.

Cahill, Prins, Weber, and McGaugh (1994) exposed their participants to a story told through slides, with one version involving violent material and the other involving neutral material. Following this exposure, the subjects in the experimental group were injected with propranolol hydrochloride, a drug that inhibits the adrenergic system and so inhibits amygdalic activity. When tested a week later for their memory of the slides, controls showed the usual enhancement of recall for the emotional content, while the experimental group showed equal recall of the emotional and neutral images.

Increased amygdalic activity has also been associated with the retrieval of autobiographical memories (Markowitsch et al., 2000). The authors noted that memories we can retrieve easily may involve affect, a possibility that would explain the engagement of the amygdalae.

It should be noted, though, that we are able to remember neutral autobiographical content, even in the case of very remote memories. From about the age of five, most of us can remember each lifetime period from then up to the present, including very dull times. The bulk of the material recalled is likely to consist of repeated, reinstated facts, events, or people, but these nonetheless qualify as remembered autobiographical content.

For instance, Jane may have worked for the Bellwel Company during a certain, boring, 12-month period, but years later she would normally be able to recall the kind of work that she did, at least some of the people

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with whom she worked, where she lived at the time, and so on. A large body of information should be available, although, as noted above, most of it would involve frequently reinstated content. Memory for individual episodes, in contrast, puts high demands on the memory function. This is the case because the content of each episode involves wholly unique actors and relations: for example, John only spoke about getting to your house through a rainstorm on one occasion, and the three other people present said what they said only on that occasion, and the dinner that was eaten was not duplicated at any other time; nor was the fact that John’s raincoat left a puddle in the hall. Although we can form clear memories of particular neutral episodes, and retain them for some time, it is in this area that distinct emotion is likely to play its most critical role. An emotional memory has the capacity to endure, resisting the massive interference of the many thousands of events that unfold across the months and years. It is therefore likely that when an individual is asked to recall a personal episode, and particularly a remote one, it is the memory carrying affect that will frequently appear in the awareness, along with the associated amygdalic activity.

The factor of interest may also play a fairly central role in the strength of memories. Content or events that interest you tend to be well retained, as compared to neutral content, even if they pass fleetingly, such that rehearsal is not in play.

CONCLUSIONS The case for the role of emotion in human memory appears to have been established on the basis of both experimental and physiological research.

The few studies that show no effect or impairment (not counting stress or anxiety) will probably find explanation as our knowledge deepens.

Some Unanswered Questions As suggested above, it is more than likely that a personal event that is emotional for us will have a greater impact than a narrative, slides, or pictures that also tap emotion but do not constitute part of our individual life histories. But at present there is no extended body of data concerning the causal role of emotion in natural contexts: that is, the emotion felt, and its impact on LTM, when an individual marries; some major loss is experienced through divorce or death; or some exciting new world is opened.

The idea of a relatively strong or weak memory function appears to be easily understood. Longevity, the presence of detail, and the absence of

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distortion can all be cited as characteristic of a strong memory. But to what extent do these separate factors carry weight when not all are present? My own bias is toward longevity: if information is retained across very extended periods, perhaps for life, I would count this as a strong memory, as in the case of recollections dating from the first year of life—however brief the content of such recollections. In contrast, a memory may be detailed for a period of time, but not endure across decades, and this I would be less inclined to view as a strong memory. Indeed, episodic information is generally recalled in astonishing detail for a day or days following the original event. Finally, with regard to distortion, this variable should perhaps not be heavily weighted. Over extended periods of time, fundamentally accurate memories may pick up certain trivial but inaccurate details, and this clearly occurs even in the case of recollections that we hold for life.

There appears to be a widely held assumption, both among researchers and laypersons, that if some element in a memory is found not to be valid, then the memory as a whole becomes suspect. This idea may reflect the older view of memory as resembling a photograph or film. If an object, say, in the left-hand corner of your film is not the original object, then it seems you are watching the wrong film. But, as suggested above, real personal memories frequently show the following property: the bulk of the information is correct although some details are not. In the personal memory detailed in Chapter 5 here, almost all of the information proved to be accurate, while a few elements were false. In the same way, my recollection of a plane trip from Houston, described earlier, proved accurate except for the detail that I recalled having inadvertently taken someone else’s seat, while in fact the other individual had taken mine. It appears likely that most of our adult autobiographical memories (i.e. those not formed under stressful conditions or conditions that involve forcing) will prove to be of the same kind. In fact, many deeply stressful events may also be recalled with a high degree of general accuracy, as demonstrated by Wagenaar and Groeneweg’s (1990) exploration of the recollections provided by survivors of Camp Erica. In summary, the fact that human recall is indeed reconstructive in nature does not imply massive or routine distortion. (The interpretation of events in a memory, though —such things as recalling an individual’s motivation, intentions, or emotional state—should probably be distinguished here from the recalling of factual content, with the former being more prone to alteration across time.)

With regard to emotion in our daily lives, even some basic questions remain unanswered at present. It is not known whether the intensity of

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the emotion, short of stress, correlates with the amount of central (or peripheral) information that can be recalled, both immediately and across extended periods, nor how the temporal factor relates to the hierarchical levels normally present in autobiographical memory. High-level information (e.g. “I was working at Belwell”) may not change from the time a memory was first formed, with details (“Two people were laid off in the week when I joined the firm”) following their own, less reliable, trajectory.

The relation between recall of semantic and image content also remains something of a blank. Bartlett had claimed that semantic content would typically outlast imagery, but is this the case, and would individual differences perhaps play a role here? All of these questions can also be posed concerning the endurance of memories across time.

The Amygdala Revisited Markowitsch et al. (2000) found that increased amygdalic activity (implying the presence of emotion) occurred when their participants were asked to recall a personal memory of their choice. This outcome probably means that emotional as against neutral memories had been selected. Such a personal memory is also likely to be subjectively more vivid than a neutral memory. In fact, recent findings have provided support for the role of the amygdala in processes that lead to enhancing the subjective vividness of memories (Kensinger, Addis, & Atapattu, 2011; Kensinger, Garoff-Eaton, & Schacter, 2007; Kensinger & Schacter, 2007). Another recent study of interest, using functional magnetic resonance imaging data, compared the brain of an individual with hyperthymesia (or near-perfect autobiographical recall) with those of controls, and found a significantly larger right amygdala and enhanced amygdala-hippocampus connectivity in the hyperthymestic individual (Ally, Hussey, & Donohue, 2013). According to the authors, the amygdala may serve to process autobiographical memory content in the context of emotional, social, and self-referential dimensions.

Further research is needed to determine the extent to which the amygdala functions within a core autobiographical network of brain structures.

A final question regarding the role of emotion in memory, and in particular the amygdala, concerns findings from the animal literature identifying a biochemical reconsolidation process in memory formation (for a review, see Dudai, 2004). Specifically, evidence is emerging to suggest that a memory trace, once consolidated, may not be in a fully mature state and thus may undergo an additional consolidation process during retrieval (Alaghband

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& Marshall, 2013; Auber, Tedesco, Jones, Monfils, & Chiamulera, 2013; Curran & Robbins, 2013; Reichelt & Lee, 2013; Torregrossa & Taylor, 2013). This idea that memories, subsequent to storage, are not fully stable, but are in a labile state when reactivated provides further support to the constructivist position endorsed by the present book.That the amygdala has been implicated as an important structure for this reconsolidation process (Doyère, De˛biec, Monfils, Schafe, & LeDoux, 2007; Sigurdsson, Doyère, Cain, & LeDoux, 2007) highlights the increasingly valuable role for future research into the relation between emotion and memory.

CHAPTER

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Memory and Schemas If John is memorizing a list of words and encounters the item BRIDGE, paying close attention to it, a memory of BRIDGE will be formed in John’s long-term store. But what is the nature of the BRIDGE memory?

How is that memory represented in long-term memory (LTM)?

A similar and also very difficult question concerns how the memory relates to the concept or schema of a bridge which John’s memory “used” to interpret the nature of the word when he encountered it. The schema supplied meaning to the stimulus. But what did that involve?

In current models of word recall, such as the order models described in Chapter 3, this second issue is not generally addressed. It is taken that the system must draw on long-term conceptual/schematic knowledge when encountering a word item, and that a representation of the item is then coded into memory. This is sometimes seen as a token of the concept.

As described in Chapter 2, it has been established since the 1950s that certain properties make it easier to retain a word in memory. These properties include frequency (how often the item has been encountered in the past), association value (the number of associations the item has with other words), imagery, and concreteness.This means that the concept corresponding to the word in LTM does have some influence on memory for the word; for instance, if the concept has been frequently activated, new instances of the concept conveyed by a word will be relatively strongly coded. In short, the background schemas affect how well a new item of information will be retained, even in the simple case of isolated verbal items.

THE ROLE OF SCHEMAS IN LONG-TERM MEMORY: A GENEVAN VIEW The Piagetian view of the relationship between memory content and the background schemas, here with an emphasis on episodic recall and higherorder bodies-of-information recall, is that all schemas exist within a matrix of other schemas in LTM, with some being more tightly integrated into this extended net than others. The greater the integration of any given schema with other schemas (with other bodies of information), the more strength the Human Memory, http://dx.doi.org/10.1016/B978-0-12-408087-4.00010-4

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schema will provide to the material that it constructs. Piaget also endorsed the view that frequency of activation strengthens a schema (strength being defined, again, as the factor that provides the capacity to maintain retrievable information in LTM).Thus, the Genevan model fits with the data on random word recall, to the extent that some properties of the relevant concept (e.g. familiarity) influence the probability of retaining a learned item.

In early word recall studies, association value involved the degree to which a given word has associations with other words (DOG has many; GURNEY typically few). Under the Piagetian model, DOG would, in most adults, enjoy a very extended matrix of content reflecting the individual’s knowledge of dogs; GURNEY, assuming the meaning were known, would have few. Thus, DOG would be better supported in memory, not because a free association test would throw up more items (friend, bone, barks, collar, leash, tail, etc.), but because of the extended matrix of associated, organized information in LTM concerning DOG. The free association property would of course be a side effect of all this content.

Since under the Genevan model abstract schemas of things that can be seen or heard are also associated with the corresponding perceptual information, and each works to support the other in memory, the imagery and concreteness factor that improves word retention is also compatible with Piaget’s argument.

In the case of meaningful prose passages or events, if you are told, “Jane wanted to make pancakes for breakfast this Sunday, but to her amazement she found that her frying pan was no longer in the cupboard,” this information will fit numerous bodies of specific, established content in LTM that are directly related to the construction of the sentence. Under Schank’s (1982) model, for instance, there will be knowledge falling into the following knowledge categories: times when pancakes are most likely to be made for breakfast, with Sunday a high contender; what people eat for breakfast; how the missing frying pan related to Jane’s goal; the various implications of it being missing; where pans are kept; and the nature of human emotion when plans are blocked, and also when a possession is missing. The input sentence fits all of these higher-order schemas (or, in Schankian terms, knowledge structures), and will be supported by them.This is in addition to the individual integration of the various concepts with others in LTM (frying pan, pancake, and cupboard, each with its own matrix of connections).

In contrast, consider a sentence such as, “Jane wanted to lift a coal waffle iron for Sunday, but to her amazement found that her skating board was no longer in the habitat.” The content does not fit with any higher-order schemas, and a series of statements of this kind, as compared to Jane’s ongoing non-pancake plans for breakfast, would be difficult to remember.

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The conclusion here is that for any given event, the relationship between entities that are seen and heard and the nature of the background (LTM) schemas that construct them is critical to the strength of an episodic memory. The same is true for prose and general semantic information.

Bartlett’s original claim had been that when content fits a specific higher-order schema, it would be relatively strongly retained in memory.

Piaget went further. While agreeing with Bartlett, he urged, as described above, that the higher-order schemas have an organization and integration in LTM itself—an essentially permanent organization—that also affects the strength of a memory.

The Standard View of the Role of Schemas in Long-Term Memory The standard approach in mainstream cognitive psychology today does not reflect this view. If, for instance, a prose passage is presented, it is assumed that some of the information in the passage as such will be coded and held in LTM, and that this, in and of itself and with no additional factor, constitutes the memory. There are just two players here: the original passage and its representation in LTM (which may well involve schematic content but in a restricted fashion—only corresponding to the concepts in the passage and their interpretation based on background knowledge). Suppose Participant X has read the following passage: Set A In 1920 Eamonn de Valera, the future taoiseach (head of state) of Ireland, newly escaped from an English prison, left on a trip to the United States in the hope of gaining support for the Irish cause. There had been debate at home over whether he should in fact stay in Ireland, but de Valera believed that he could be more useful in America, both in terms of gaining money for arms and of influencing public opinion, a powerful political force that had arguably saved some of the captured rebels from being shot (executed) in 1916.

What Participant X can recall a week later might correspond to: Set B In the early twentieth century, de Valera, who was later the president of Ireland, went to the United States in the hope of gaining support for the Irish fight against the English. American support may earlier have saved some of the rebels from being shot.

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Under dominant mainstream theory, the relevant content in LTM consists of the information described in Set B, probably wholly in propositional form. That coded set consists of all that is involved, say after 7 days, in the work of maintaining and retrieving the memory, and the schemas brought into play during encoding (and now again at retrieval) are engaged in no other role than the provision of information.

Under Piaget’s view, the situation is more complex. It is complex to the point that it is difficult to illustrate graphically. Each schema brought into play during encoding, from concept level to higher order, is embedded in a matrix of other schemas that are not involved in this immediate memory. For instance, “Ireland” may show strong associations with fiction and poetry written in Ireland, with that country’s relation to Christendom, and much else, but none of this will be drawn on in forming the present de Valera memory. Even so, it will play a role in the support of the de Valera memory, being an extended matrix of information in which the Ireland concept is embedded. The same goes for higherorder interpretations of the target passage itself. For instance, knowledge of how another country’s opinion might influence events in country X, usually because X is dependent on that country in financial ways but also at times in political ways, such as the desire to play a role on the world stage, may all be present in the knowledge structures used directly to construct this passage. Critically, however, this body of passage-relevant information will be associated with other political content that has no direct application to de Valera in the United Sates: but if it is extensive, it will support the schemas used to construct the target. And these other bodies of information in their turn, associate with yet other knowledge— with other schemas.

When you first begin to learn a subject, often the hardest part involves exactly those early stages. You are encoding knowledge, but it does not fit as yet—or not tightly and well—with other knowledge. I used to wonder why students in introductory psychology sometimes complained that this simple material was difficult, while I heard no or few such complaints in courses at the 200 or 300 level—introducing more complex ideas. Now at least I have a theory concerning the issue.

Under the present model (also endorsed in this book), the cognitive representational network is fully inter-associated, in one way or another.

Some information shows tight extended and often duplicated (available from several sources) connections, however, while some are relatively isolated.

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When it comes to the relatively isolated information, if last week you met a friend on the street and she wore a beige dress, and a week later you try to recall the dress, you may fail, or even remember falsely. Almost nothing constrains a color memory: unlike knowledge of political actions that fit or fail to fit your knowledge of political events, the dress could have been green or brown or blue; the only real association it has is with the fact of color, and of the colors in which dresses are likely to appear without exciting surprise. Somewhat “isolated” or trivial facts like this have poor schematic support, and tend to be quickly forgotten.

CONCEPT SCHEMAS IN WORD RECALL AND EPISODIC MEMORY It was stated above that the properties that influence the recall of individual words derive from the concept represented by the word. McGeoch (1942) established that when we memorize a word item on a list of items the primary code deployed in LTM is a semantic code: it involves the meaning of the word. This had been discovered through an examination of similarity-based interference effects. McGeoch had manipulated auditory, visual, and semantic similarity across different lists. High levels of auditory/phonemic or visual similarity had no measured effect on memory; in contrast, semantic similarity produced significant interference in order recall. It is now believed, as urged by Underwood (1983a), however, that although the primary code here is semantic, other, weaker and generally short-lasting, sensory codes are also established.

But this returns us to the question of what aspects of the semantic code (what aspects of concept schemas) are in fact entered into LTM when a word memory is established and maintained. And what aspects of the same entities are involved in meaningful episodic recollections and the learning of bodies of coherent information?

McGeoch’s work showed that what is entered into LTM is not a token of the word, but rather semantic content, and Tulving’s research into the effect of cues further strengthened this position (Tulving & Osler, 1968; Tulving & Thomson, 1973). Tulving’s data also indicated that a fairly extended set of “features” (or body of information) is involved. The way in which the individual thinks about a target item during learning influences the information present in the resulting memory in LTM. If the target is BIRD and a participant memorizes BIRD while thinking about insect-eating birds, the resulting memory significate will differ from that formed if the same item, BIRD, had been encountered within when he had been thinking about eagles (Tulving & Pearlstone, 1966).

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The Divorce Hypothesis Tulving’s interpretation of these data centered on the view that a concept consists of a large set of features possessed by exemplars of the concept. The bird concept would thus include all bird features known to the individual, including those relevant to small and large birds, to insect-eaters, and to birds that prey on animals. When a list of items is learned, the system forms a new-memory complex, reflecting the set of items on the list, in LTM.The particular features entered for each word item into the memory significate depends on the thought context operating at the time of learning. Under Tulving’s model, however, once the new memory (of the target words) has been formed, it no longer maintains contact with the concepts drawn on at the time of encoding. That is, no further association would be maintained with the bird concept following the learning of the list. This was characterized earlier as a divorce hypothesis.

Tulving derived these conclusions from the fact that if the individual was probably thinking of insect-eating birds at learning, then cues relevant to those birds were effective in providing recall of the target item. But cues relevant perhaps to eagles or other birds unlike insect-eaters were not effective. The data thus suggested that the bird concept as a whole was not coded into the new memory. Other researchers, however, showed that while cues not related, say, to insect-eating birds (in the present example) were much less effective, they nonetheless did aid recall to some extent, or in some cases (Nairne, 2002b; Nelson & Brooks, 1974).

The striking discovery here was that the memory codes reflecting the learning of BIRD were clearly not identical across different situations. As described in Tulving’s 1983 book, this view was vigorously rejected by the majority of memory researchers across the 1970s. Apparently, it seemed obvious to them that the item BIRD must mean BIRD, and not a range of other information; similarly, TABLE must mean TABLE, and GARDEN, GARDEN.Yet the implications of the—thoroughly replicated—data were clear. The memory codes across situations were not the same. On first reading this work, I was reminded of a scene from White’s (1958) book, The Once and Future King, in which the boy Arthur meets the magician Merlin in the woods. Arthur wonders why Merlin has an owl—it is called Archimedes—on his shoulder. But it is not Merlin who answers. “There is no owl,” said Archimedes.

But there was an owl, no less than on Merlin’s shoulder, in the case of Tulving’s data. The memory significates formed within different contexts, of the same word representation, differ.

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Under the model of human memory endorsed in the present book divorce of one body of information in LTM from another does not happen. The foundation of the very nature of memory is association; that is, one body of content will make contact with another. So the varying effect of cues needs to be explained on a different basis; that is, not through the assumption of two bodies of content becoming divorced.

One approach to the issue could be described as follows. When a memory, Memory X, is formed, highly activated content within the relevant schema forms the memory X significate in LTM. If an episode is involved, such as “The day we went to Toronto,” then the body of information coded to represent that day will constitute the memory significate. It will be distinguished from other memories. How the system achieves the separation from other memories has not been established, but subset links from headers to the other information could produce this individuating effect, as suggested in Chapter 7. The same situation would obtain in the case of random words. Thus, cues that correspond directly to information in the significate should be effective cues.

Under the present view, when a memory significate is formed, certain information will be coded directly as part of that significate. But associative contact is maintained with content present in the relevant schemas, including content that has not been drawn on as part of that particular significate.

For instance, if John was the person who had visited Toronto, he would be likely to possess knowledge concerning the city that did not come into play across that particular visit. But given the continuing associative connection between the Toronto memory and the Toronto conceptual schema, a cue that contacted some aspect of the Toronto schema would provide the possibility at least of association spreading back into the Visit memory significate. And in the case of a word item such as BIRD, learned within a thought context of insect-eating birds, the cue “talon” might work, for the same reason. But it should be far less effective than a cue such as “crow,” or even “insect.” This interpretation can at least accommodate the data on strong and weak cues described above.

THEORETICAL MODELS OF SCHEMAS This leads to the question of the nature of concepts/conceptual schemas as such. It was suggested above that, for adults at least, they generally contain a large body of information. Also, concepts involve another kind of differentiation. I distinguish my concept of a table from my concept of a chair.

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Similarity-Based and Identity-Based Models When it comes to this kind of differentiation, theoretical approaches fall into two groups: similarity-based models and identity-based models. We consider all tables to belong in the table concept, while chairs do not.

Under a similarity model, the reason that all tables become categorized together is that they share various kinds of similarity across the group as a whole, although there need be no particular property that all share in common. This view, advocated by the positivist philosopher Wittgenstein (1953) has dominated psychological thinking for 50 years, and a wide range of similarity-based models have been developed, from prototype to featural to probabilistic. Some focus on similarity among exemplars, as described above; some posit that we learn the typical features of exemplars of a concept and store this knowledge, such that if, for instance, a newly encountered creature possesses many typical dog features, it will be conceptualized as a dog. The critical point here is that the concept itself is defined and determined by the typical features. A variety of other approaches have also been explored (Osherson, Smith, Wilkie, Lopez, & Shafir, 1990; Smith & Medin, 1981; Smith, Shoben, & Rips, 1974).

The alternative, identity, view posits that we conceptualize all tables as belonging to the same concept because each table has certain properties that qualify it as a table, such that all exemplars of this concept do possess something in common (the qualifying-as-table property or properties).This line of thought traces its descent from Aristotle through Kant and Piaget, and is more compatible than similarity-based models with constructivist ideas in general. Under the identity view, the basis of conceptual membership—the qualifying property—in the case of semantic (as against perceptual) concepts is almost always a function, or a closely related set of functions.

In the case of the table concept, the critical function could be translated into words as something corresponding to “a free-standing object designed to hold smaller objects above the ground on an extended flat surface, for the greater convenience of human use of those objects: elevation from the ground is achieved through legs.” (The translation into words is probably a crude expression of the system’s capacity to represent function.) Under the present model, if an object possesses the property defined above, it is a table. Thus, membership in the concept is determined by the individual nature of the exemplars (an identity principle), as against similarity to other exemplars or similarity to a set of typical features. Since the present line of thought has its remote origins in Aristotle, I will call it the neoclassic tradition here.

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Components of a Concept Recent proponents of the classic tradition widely understand a human semantic concept as consisting of three components (Putnam 1975a, 1975b). First, there is the expression of the critical (“necessary”) function that determines conceptual membership, as in the description of a table offered above: this is often called the core. The core cannot include two or more sets of different properties: it involves a unified meaning. That is, it cannot be either A or B, with A and B embodying different functions.

Current theories assume that a concept includes information concerning all the actions that exemplars could perform (as known to the individual), and not just the core functions; this departs from the original Aristotelian view. Even so, only the core determines conceptual membership.

The second component of a concept, under the present model, involves perceptual information concerning what exemplars of the concept look like or sound like, and so on. This would include size and shape information. (There may also be some abstract codes that also specify possible sizes and shapes.) The third component is a body of general knowledge concerning exemplars of the concept, or other properties relevant to the concept, including all information that the individual knows—in most cases, for the adult, again, a large body of information.

This approach fits constructivist models in that it assumes complex unconscious functions operating in the development of a conceptual schema. For instance, most objects could perform various functions. A table could be used to wedge open a door. But under the present view our cognition is capable of identifying the activity that is most fundamental to the entity—which in some cases may be considerably more obscure than the function provided by tables.

Identity models posit that conceptual schemas operate in a hierarchy, with lower-level concepts nesting directly under their superordinates. For instance, from the lower class to the highest the idea kitchen table shows the following pattern: kitchen table → table → furniture → nonliving thing → thing. In the same way, for the spaniel concept the hierarchy would include: spaniel → dog → mammal → living thing → thing. One critical aspect of this structure is that the lower-level constituents inherit the cores of all representations directly above them in the hierarchy (a spaniel is a dog, is a mammal, is a living thing, etc.). This involves the Kantian view that some concepts depend on others for an essential part of their meaning.That is, although different levels in the hierarchy involve separate representations that can be clearly distinguished from one another (“dog” and “animal” do

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not reflect the same idea), it is critical to the meaning of dog that a dog is an animal. If you did not know this, you would hardly know what a dog was.

As in the case of autobiographical hierarchies, it is believed that content at the higher levels of conceptual organization are coded at greater strength than those at the lower. For instance, John may see some lilies on a kitchen table and later recall that he had seen flowers, but no longer remember the type of flower.

Reevaluating the Misinformation Effect Using Conceptual Hierarchies Pansky,Tenenboim, and Bar (2011) examined what happens in the misleading information paradigm when the target and misled items involve different basic level concepts. The idea of basic level concepts was developed by Rosch, working within a similarity tradition, and has since been extensively pursued (Mervis & Rosch, 1981; Murphy, 1991; Pansky & Koriat, 2004; Rosch, 1973, 1975; Rosch & Lloyd, 1978; Rosch & Mervis, 1975; Rosch, Mervis, Gray, Johnson, & Boyes-Braem, 1976). Under this view, there is a certain level in the conceptual hierarchy that is more “basic” than the others. This involves the highest level at which an image can be formed of exemplars; further claims include the hypothesis that this level reflects the first expression of the concept developed by a child. For instance, Dog, Table, and Boots would be basic level, while Animal, Furniture, and Footwear would not.

Pansky et al. (2011) first replicated the standard misinformation findings, such that the target item might be Gold Ring, and the misleading item, Silver Ring. But under another condition an example of the type of item was: target Gold Ring followed by the misleading information, Gold Earring. Here, there was no misinformation effect: being exposed to Gold Earring did not impair the ability to recall Gold Ring. The authors tentatively attributed this outcome to the fact that Ring is a basic level concept and so would be strongly coded, and available at recall to correct any inclination toward choosing Gold Earring.

Within the body of past research involving the misinformation effect, however, target and misleading items reflecting basic level concepts have been used quite frequently. Hammer and Wrench, for instance, would qualify as basic level concepts, and with these items there was a reliable misinformation effect. Thus, an explanation in terms of basic level properties may not be adequate to explain the Pansky et al. data. Nor did the study involve a concept/superordinate concept structure, since “gold” or “silver”

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are not conceptual subsets of “Ring,” but merely possible properties. Even so, examining the relationship between target and misleading items and their direct superordinates is an intriguing idea, which could open some new avenues of research. And of course the findings of no interference operating between Gold Ring and Gold Earring need explanation.

Contextual Influences Wittgenstein—launching a similarity-based tradition—had urged that members of the same concept could mean entirely different things when encountered in different contexts, thus implying that no core property existed (Wittgenstein, 1953). For instance, if you watched a police dog being trained, and saw the dog fiercely pursue, leap at, and bite the (protected) arm of the trainer, you would be likely to think of dog in this context as something large, fierce, and trained but potentially frightening: with large teeth. If in contrast you watch sheepdogs at a fair, doing their work, you would be likely to think of dog as something of medium size, intelligent, attractive, not aggressive (even with sheep), trained, and not frightening.

The two bodies of information barely overlap; the two meanings of the notion “dog” are, under this view, wholly different.

In Wittgenstein’s positivist philosophy, the meaning of a thing, in any context, depends on the appearance and actions of that thing within that specific context only. Thus, meanings could indeed differ completely from situation to situation. Under the neoclassic (and constructivist) view, in contrast, background information would supply basic general knowledge about dogs in any instance that a dog was encountered. Again, our cognition would go beyond the immediate sensory experience; it would not, on each occasion, operate as if we had never seen a creature of this kind before.

What, then, of the obvious differences in the information activated by the police dog and by the herding dog? Under the neoclassic model, the adult conceptual schema would typically include information concerning the appearance of these (and other) dogs, and also knowledge of their likely activities. When watching the police dog, the knowledge relevant in particular to police dogs would be strongly activated, and the same would occur with the herding sheepdog. The appearance and behaviors of each, as seen, would be entered into the newly formed memory. As this occurs, the incoming information should be matched with the relevant subcomponents of the dog schema. And what was seen would normally be compatible with the specifications of the schematic knowledge (the sheepdog would behave in ways anticipated of sheepdogs, and so on). The result, as

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described in earlier chapters, would be an increase in the strength of the memory (as compared to content that did not match a schema) and the capacity to predict activities likely to occur next.

If this matching process seems unlikely—a kind of constant monitoring of the world against background models—consider the reaction of an adult in this culture who attends a sheep fair in which the sheepdogs arrive wearing colored outfits, line up, howl, and turn somersaults—while ignoring the sheep. At the very least, this should cause surprise.

Activity Models The models of conceptual representation introduced here center on the belief that codes reflecting the actions of objects or abstract entities—what they can do—form the basis of semantic information: they supply meaning.

These could roughly be called activity models.

In line with the argument outlined above, Bransford and McCarrell (1974) suggested that exemplars of a concept can typically perform many different behaviors. Some are active (a man could paint a wall) and some passive (a tree can provide shade). In any given episode, a subset of the actions possible for that entity (all stored in the relevant conceptual schema) will be involved and others will not. Further, the events that unfold in our lives involve a very large quantity of information: there are the objects and actors, and possible movements, each of which will change the spatial relations among all the entities within that spatial context, and ongoing interactions of many kinds. And in almost every case, all these constituents are unique, and so must be recalled without the prop of repetition: we do not live through identical, repeated episodes across time. In the case of actual events, though, all of these motions will be possible or lawful. That is, the activities for each constituent of a memory are possible for that constituent, within that particular context; or else the event could not have happened.

Further, every interaction, say of A and B, must involve not only movements of which A is capable, but also an interchange of activity with B in particular, of which A is capable—and B is capable. And so on for all the other elements of that episode.

The human memory function tracks all this. It would have been difficult to establish the reality of such tracking, except that the rules of what is possible can be violated in prose and speech. Suppose I am told, “John was on the beach when he saw a boat drifting half a mile offshore; he at once picked up a paddle and managed to turn the boat by thrusting the paddle against it.” I will reject this as having actually occurred. I know the

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length of paddles, and other properties relating to an ocean context, and I know that this interaction is not possible. In a famous study involving apparently incomprehensible prose passages, Bransford and Johnson (1972) were able to show that if certain relations and interactions are described, but our cognition cannot interpret or “see” how these would be possible within the particular context involved, the material is perceived as not making sense. And, critically, the resulting memory function is very poor. In short, we map the actions we perceive around us, or read in prose, against schematic knowledge that includes specifications of the motions of which any given entity is capable, and also whether Motion X of Element A can interact with Motion Y of Element B. And critically, when the events as experienced fit with the schematic “rules,” the resulting memory will be relatively strong.

If a friend pours tea into a mug and then turns the mug upside-down, but no tea spills from it, I will trust my schematic knowledge. I will think that I am being tricked, or that I was wrong in thinking the tea had gone into the mug, or perhaps that there is some kind of flap inside.

One critical point here is that the quantity of information involved even in “simple” memories is enormous. And, from older child to adult, schematic knowledge plays a lion’s role.

PERCEPTUAL AND MOTOR SCHEMAS IN MEMORY The neoclassic view holds that a clear distinction must be made between the way a thing looks or sounds (perceptual information) and our cognitive understanding of what that thing is (semantic information). Within this context, Bruner (1957) offered the compelling example of a poisonous mushroom. The mushroom might be large, white, spotted, and fringed. So much for its appearance. But if you ask what a poisonous mushroom “is,” the answer would be something like, “It’s a fungus that can make you sick if you eat it.”

Bruner chose to study only the perceptual aspect of concept exemplars, holding that we know so little about semantic codes that any attempt at research within that context would be premature. Nonclassic researchers, however, later borrowed his methodology under the assumption that perceptual “features” (what a thing looks like) could be applied no less than abstract features to the study of conceptual meaning; in short, that the two kinds were not distinct (Griffiths, Canini, Sanborn, & Navarro, 2007; Love, Medin, & Gureckis, 2004). In contrast, a researcher in the neoclassic

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tradition would suggest the following. Suppose a given individual, Bar, has lived in a culture in which there were no chairs. Bar then travels to America, where he spends a week in a hotel room stocked with several of these objects. By the end of the week he might have an excellent memory image of each chair, and so knowledge of how these things look, and even knowledge of their parts. But if he did not know that we use them for the purpose of sitting, it would be reasonable to say that he did not know what a chair was, and so did not have the concept. Under this view, imagery does not supply meaning.

Schema Development in Infants As Piaget described the development of the semantic component of schemas in infants, the relevant information derives from the child’s own actions (Piaget, 1952, 1954). For instance, the child would discover that when he pushed certain objects, they would move; and when objects showing certain properties, such as roundness, were pushed, they would roll in a distinctive fashion.

Under the Piagetian view, the infant spends perhaps the first 17 months of life (the sensorimotor period) developing a large repertoire of motoric responses to the things seen around him After this point, the motor schemas providing the capacity to act on objects would transform into codes specifying the movements and interactions of which the objects, themselves, were capable. Certain entities can move, and certain entities can roll and some can be physically contained by others. A grasp of many activities of this type provided the primitive building blocks of conceptual meaning—knowledge of the motions and interactions of things in the world.

Under the present view, a spoon schema would include core information specifying an object of a certain size and shape, whose function was to convey small amounts of food or liquid a short distance, from some source (typically a plate or container) to the mouth. Also, the typical means of transportation would be a hand. As the child developed, other functions would also be discovered, along with extended general knowledge (spoons tend to be kept in kitchens). This is of course an identity model: a thing meeting the core properties described above is a spoon, and a thing not meeting those properties (in its natural, undamaged, state) is not a spoon.

Piaget believed that the content of schemas was constructed as the child develops, with almost no innate component beyond the work of reflexes and a cognitive system geared to interact with the world in such a way

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as to gradually build the structures that could interpret sensory experience. This view differed from that of Kant, who held that the interpretive capacities are innate; that is, on encountering certain perceptual information— perhaps seeing an object move—the human mind would have a biological capacity to understand the concept of movement. On seeing one object impact another and change its trajectory, the mind would bring into play an interpretive function involving the idea of causality. In this opposition between the two, Kant is of course closer to the views of Chomsky (1957) concerning our acquisition of syntax, while Piaget’s model emphasizes cognitive development created little by little through interaction with the environment.

Piaget’s body of research makes a strong argument for the view that the various forms of abstract understanding that we bring to experience are not built into us fully developed from the beginning (or appearing as the brain reaches full physical development). Experience influences the competence of our thinking, and this competence further appears to be domain specific.

But the data emerging now seem to indicate that some of the interpretive tendencies are indeed provided biologically, and these go well beyond reflex responses, from the early months of life. The issue is examined in the following section.

As described in Chapter 8, one of the major difficulties confronting a symbolic theory of representation centers on the issue of meaning. A symbol is an arbitrary designator that does not resemble, or exhibit any properties related to, the thing that it designates. ** could be used as a symbol for house, although ** has no house properties.Yet, when we activate concepts, there is a strong subjective sense of meaning. I feel that I know what a house is, and this feeling includes some quality of being real. In other words, while ** does not carry meaning, it seems there is something in my cognition—in my mind—that does.

In Piaget’s model, the young child’s actions on objects become truncated and internalized as the “other side” of those actions, that is, what the object itself can do. These activity-specifying codes, under the Piagetian view, are analog of type. That is, a constituent representing motion embodies motion in some way. It is not a symbol. Thus, the fundamental level at which meanings are built incorporates in some cognitive fashion the actions for which they are the code.

At first, this claim might seem implausible—for how could some form of neural action, or rather the cognitive emergents from that action, directly express containment or movement or physical contact? Yet this is true of

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perception. The percepts that we experience are of course analog codes.

If two things are side by side, and one, A, extends over a larger space than the other, B, in the perceptual field, this is because A in fact extends over more of external physical space in the world than B extends. It is larger.

If a perceived movement brings left-to-right changes in perception, it is because the moving thing being represented is indeed traveling left to right.

We have no model for how analog representation can somehow duplicate or embody properties of the external world in this fashion. But we know through our visual experience that it can. The claim for an analog activity code is therefore not unreasonable. We simply don’t have a model for it at this moment in time (Some would argue that we do have a model, but it isn’t clear that this position has adequate empirical support.)

The Role of Image Schemas in Early Thought Processes Under a long-standing empiricist tradition, it has been widely assumed that the child’s first conceptual representation involves sensory images, that is, perceptual information.This is seen as involving, in most cases, the image of a particular exemplar of the concept. For instance, the child will be told that the family pet is a dog. Thus, the appearance of that particular animal will embody the concept dog, and other entities that strike the child as closely similar will gradually also be incorporated into the concept. Today, issues can be raised concerning whether the original image involves true representation, but the important idea here concerns the view that the memory of an individual exemplar provides the earliest form of the relevant concept.

As research has continued into the cognitive development of infants, it has emerged that many of the abilities first identified by Piaget emerge considerably earlier than Piaget himself had thought. For instance, by 3 months infants understand that the world is divided into objects with boundaries that move independently of their context, such that if you push on say an orange-colored object, A, A will move, but other, non-A, objects will not move (Spelke, 1985).

And by 5 months, the child also grasps that objects are essentially permanent entities; if one vanishes from sight, it still continues to exist (Baillargeon, Spelke, & Wasserman, 1985). But perhaps the most striking discovery of all involves the following. Abstract conceptual representation begins very early, albeit in a primitive form. It can be found in infants as young as 4 months. Also, these abstract meanings appear to be in play well before the infant begins to use a visual image of, say, a dog, within the context of conceptual representation.

This new insight has emerged from the work of Jean Mandler and her colleagues (Mandler, 1988, 1992, 2000; Mandler & Bauer, 1988; Mandler

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& McDonough, 1993, 1998). But how could the internal cognitive world of a 4- or 7- or 9-month-old child possibly be discovered?

Infants become bored if repeatedly presented with the same stimulus, or same kind of stimulus. Thus, if you offer a red object again and again, and then a blue object of the same shape, the infant is likely not to stare at the final red stimulus, but to show interest again when presented with the blue one. At least, if this does occur, the pattern indicates that the child can discriminate red from blue; this technique has been useful in determining what an infant can or cannot perceive. Mandler used the same approach (boredom as against interest) to examine the way in which infants begin to develop conceptual representation.

It emerged that infants are particularly responsive to movement. Also, the first forms of representation—codes that embody meanings—involve content that would operate close to the top of the adult hierarchy of concepts. The process appears to operate top-down, rather than bottom-up.

Mandler established that one of the first distinctions made by babies (concerning the world around them) is the distinction between animate and inanimate things. If the infant is presented with a series of small models of, say, vehicles, there will at first be interest and then lack of interest; the child has become bored. If then a model of an animal is shown, the child’s attention is caught again. The same occurs when a series of animals is first shown, followed by a switch to something inanimate. As the infant becomes old enough to reach and grasp, the tendency is to grasp the interesting, new kind of object—which will be something animate if following a series of inanimate things, and vice versa.

Similarity of appearance plays no role at this stage. If a series of bulky cars and vans were offered, followed by say the model of a turtle with a similar bulky outline, the child will be likely to lose interest in the vans, but to attend again for the turtle (this would hold for children who are familiar with turtles, and have seen them move).

With regard to the emergence of high-level, abstract meaning primitives across this early period of life, it is of interest that if the brain becomes damaged in later years, such that the individual begins to lose conceptual representation, the concrete, lower-level concepts (such as “table” or “lion”) are lost first, while more abstract forms, high in the hierarchy (“furniture” or “animal”) continue to function. If the brain deteriorates yet further, then even the highest-level representations are lost (Wilson, Baddeley, & Kappur, 1995).This appears to reflect a pattern in which the earliest-formed classes are the most resistant to damage, while the later-formed are relatively vulnerable.

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Another point of interest: concerning the early appearance of primitive ideas about animacy and inanimacy, this capacity emerges months before the young subjects show any discrimination between say a dog and a rabbit.

The infant exhibits an early grasp of certain other abstract properties of the world, such as the comprehension of containment and support, contingency, causality, and agency, i.e. the fact that certain entities initiate actions and make things happen (Mandler, 1992). A striking aspect of this extended research is that the capacities emerge while the infant is too young to be able to move about a good deal in the environment, or manipulate objects to the point where he or she can develop a large repertoire of actions.

The cognitive understandings (containment, support, contingency, etc.) are constructed simply on the basis of watching objects and people as they move and interact.

The world of the infant is of course full of movement. Parents pick things up and put them down; they walk with objects in their hands. When things are put down, they are put down on some kind of surface (the object is brought into contact with a surface before it is released). If the infant has siblings, they move about too, as would the family dog. Containment is illustrated when liquids are poured into cups, or toys taken from or put into boxes, or cups and other objects are placed in kitchen cupboards. In short, the child lives in a world in which movement and interaction occur constantly.

Even so, the discrimination of animate from inanimate on the part of a 4- or 5-month-old child seems quite amazing. To interpret these data, Mandler drew on work pursued in the field of cognitive linguistics (Johnson, 1987; Lakoff, 1987; Langacker, 1987;Talmy, 1985). Here a topic of central interest has been the content of the schemas that code for meaning, and in particular the content that operates as the foundation—the primitive basis—of such meaning codes. It had become clear from various areas of research that some form of conceptual representation exists in infants prior to the acquisition of language, or even in the absence of (verbal) language, as in some deaf children (Bloom, 1970; Bonvillian, Orlansky, & Novack, 1983; Bowerman, 1973; Brown, 1973; Newport & Meier, 1985). What form, then, do these preverbal concepts take?

The models emerging from this tradition posit that the infant brain recodes the physical movements of objects in the world into a relatively abstract language of thought. The abstract representation can be seen as being analogous to the physical motions and interactions that have been observed directly. For instance, we form ideas of abstract containment on

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the basis of physical things being contained in other physical objects, as in a box. “Containment” at a nonphysical level can include many forms of understanding. For instance, all cars are “contained” in the car schema (they belong in that class), and also in the “vehicle” schema. Similar parallels can be made across a wide range of abstract thought. It is also urged within this tradition that the “deep” codes used to express both physical movement and interaction, and the operations of abstract cognition, are of the analog type.

The following events are also posited. An infant watches the objects and movements around him or her, and performs what can be called a perceptual analysis on them. This involves a “redescription” of, for instance, individual, specific movements into a general representation of that type of movement. This general representation is described as an image schema.

(Different image schemas will be developed for different spatial conditions or different activities.) The image schema is not an image. That is, in the present example it does not express a particular movement in a particular context, or even a series of such movements (each of which could be seen individually). It involves an abstract code specifying movement as such: it encompasses all possible movements of that type. The image schemas then form the building blocks of conceptual meaning. That is, many such schemas may be integrated together to form a concept.

Mandler (1988, 1992) suggested that the idea of animacy and inanimacy can be built from perceptual observation in the following way. The infant observes numerous movements. She thus develops a primitive comprehension of movement through space. Mandler designates the schema relevant to a moving object as a PATH. A PATH has a starting point and a trajectory.

Infants are particularly interested in movement as against static stimuli, and more interested in self-generated movement than any other form. And— critically—the infant notes that some “things” can move by themselves. No outside entity or force is needed to produce the movement; they just move.

Further, the entity that moves by itself can also spontaneously change direction, and may show erratic shifts too—going this way and that.

In contrast, other things in the world move only when pushed or pulled or picked up, that is, when some other entity makes physical contact with them. This contact involves an image schema known as a link. A link is the cognitive understanding that one “thing” can influence another “thing.”

Here contact has been made with the nonself-moving object (usually by a self-mover) such that it does in fact move. For instance, a parent might roll a ball across some flat surface. The action now, though, tends to be in

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a straight line, and there will normally be no sudden changes or reverses.

Notably too, the nonself-movers tend for the most part not to move at all.

The infant is beginning to distinguish two broad categories of things: the self-movers, and the nonself-movers. Further, they show different kinds of motion. For instance, the animate kind (but only that kind) can show link properties at a distance. The infant discovers that animate things may respond to her smiles or vocalization, even though at that moment there is no physical contact between them. The response is nonetheless contingent: B responds to some activity on the part of A. The way in which this comprehension develops may not always be in the manner anticipated by an adult observer, though.

Concepts are built from combinations of the relevant image schemas.

For instance, an animal concept would emerge from the combination of “moves by itself,” “shows changes in the direction of motion, speed, etc.,” “may contact nonmoving things and then they will move” and “may respond at a distance.” T hus, the first concept of the family dog would center on the presence of these properties, and correspond to animate/animal in adult terms, with a rabbit or a mouse at this stage being considered “the same kind of thing”—not differentiated. These latter may look quite different, but the first primitive meanings involve “what the entity does” rather than its appearance.

Many later refinements will emerge. Apparently it is common for young children to note that animals often show a mildly up-and-down motion when they run, such that the child may make an animal toy or model hop when simulating its movement. The idea at this point appears to be that animals as such move in this way—for fish will be made to hop no less than dogs (Mandler, 1992).

Some grasp of causality (or perhaps just contingent action) also emerges early. As noted above, by 4 months, a differentiation is made between caused and noncaused motion. In further support of this view, infants show surprise when a hand seems to move an object without touching it (Leslie, 1982, 1984). Thus, in the work of understanding the world, the child has grasped that movement is not one of the things that can be caused at a distance.

As noted earlier, Piaget’s research provided clear support for the conclusion that cognitive understanding develops based on input from the environment, i.e. the more a capacity is fed by experience with the relevant materials. (The more a child deals with, say, the transfer of liquid into different containers, the better her understanding of the properties of liquids will

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become.) This means that limited experience of the properties of things in the world is not sufficient to trigger some already fully developed, innate cognitive understanding. The structures need to be developed through extended practice and use. The same has emerged in the case of the first image schemas, such as the SUPPORT schema. Kolstad (1991) demonstrated the following progression: at 3 months, the infant knows that if an object is placed in full contact with a surface, the object will be supported; by 5 months, the idea has developed that support can occur with only partial contact; and by 6 months, the understanding is that support can be partial and still work, or it can be partial, with support not being achieved.

We tend to think of perception as being an automatic and innate process. When we look at a vase of flowers, we see the vase of flowers. There is no conscious direction of the process. But it should be noted that the development of these visual capacities require extended practice on the part of infants. Infants spend a lot of time staring at the world, and so building their visual competence. Mandler favors the view that developing the first image schemas is a more “directed” and voluntary process, but the case can be made that the constructed knowledge occurs in a sense automatically— much like the ability to perceive. The individual needs to attend to the relevant stimuli in both cases. But, given such attention, the assembling of neurons needed for competent perception, and the assembling of neurons that can, say, interpret movement, may simply be something that the brain does—given the right stimulation.

As the child grows older, he will begin to notice the “features” of the things in the world around him. He will notice perceptual features (peas are green) and the parts of objects (tables have legs). At this stage, finer distinctions can be made within the already-developed activity concepts. These should include more detailed information concerning activities and, again, information concerning features. Rabbits tend to be smaller than dogs, have a different body contour, and longer ears. And so distinctions develop between tables and chairs, or rabbits and mice.

Image schemas are believed to involve analog codes. They are represented, though, in the form of the abstracted images that summarize the many different forms of individual movement and interaction that can be observed directly. Thus, a supporter of the image schema approach might say that the redescription from perceptual to semantic information can be explained as a kind of abstraction of experience, based on information provided immediately through the senses, and as such a code at least derived from, or based on, sensory information.

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Symbolic Coding Within this general line of thought, the basic, “deep” codes that provide meaning to our concepts involve the representation of actions. And these are not symbolic: they embody in some fashion the things that they represent. When I understand a spoon as an entity that can be moved in a certain way, I possess a representation of “movement” and of “containment” (for the bowl part of the spoon) that actually embodies, in some cognitive fashion, these properties. In short, I really do know what a spoon is.

But it would be hard to imagine the large bodies of information present in a conceptual schema as entities that could be readily manipulated in thought. There appears, then, to be general agreement that at another level these large sets acquire tokens—symbols—that represent them. Thus, if I am thinking about a certain country, the relevant information will be expressed in symbolic form, and manipulated in thought in that form. If the country is Chile, then a symbol for Chile will be activated. Most psychologists believe that these symbols involve some cognitive state of the brain, and not language as such; that is, the symbol is not the word item “Chile,” although it can be readily translated into a word (Anderson, 1990).

The symbol will maintain contact with the more extended body of information in the conceptual schema, such that aspects of the latter can be brought into play as needed. Also, the words associated with the symbols are capable of conscious representation. This contrasts with the language of the schema itself, which, under hard-line constructivist theory, cannot enter awareness. Even so, symbols representing most aspects of the schematic information can probably be generated.

Thus, at what are generally thought of as the higher levels of a concept, propositional, symbolic coding comes into use.

CONCLUSIONS Piaget believed that the activity representations (forming the bedrock of meaning) were internalized, truncated, and transformed motor codes: the motoric language for acting. Image schema theorists, in contrast, lean toward the view that the mental language here involves redescribed sensory/perceptual information.

The claim that the primitive meaning codes appear before the child has developed extensive motor skills, such that transformed motor codes could not provide the “activity language,” appears fairly compelling. If it is correct, then Piaget’s interpretation is wrong. Equally, however, abstract meaning

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codes (containment, support, causality, etc.) represent states present in the world, and motions. These things do not consist of perceptual information.

For instance, it is possible to see various changing images when one object becomes contained in another object. But these changing images are just that: a series of changing images. They are not a representation of the fact of containment, although they can indicate to the viewer that containment has occurred. If, however, we understand the abstract reality of containment as such—as a concept—then this representation cannot consist of perceptual information, since it is something different from imagery. It is also difficult to see how a recoded image or set of images could become a representation of the abstract fact, unless the recoding provides a qualitatively different form of content.

A third possibility here is that the relevant codes are neither redescribed motoric information nor redescribed perceptual information. The brain appears to be remarkable in its capacity to translate one kind of informational “language” into another. Light waves of various intensities strike the retina of our eyes; these become translated into line contours expressed in a spatial frame—in the end, after a great deal of processing, into bounded images (Marr, 1982). It is possible, then, that certain forms of sensory, visual information, such as that seen when an object moves, become translated within the brain into yet another, qualitatively different, code: one that directly represents motion. And the same is possible of course for other states and conditions: when a ball strikes another ball and causes the latter to move, the resulting perceptual information may be interpreted in the form of a cognitive representation that directly expresses causality. A language of the mind, representing various conditions and forces and motions, may be triggered. This third model is the one endorsed here.

Under the present view, we possess wholly abstract concepts of such things as movement, causality, and so on, because the human brain has the capacity to take visual information and translate it into abstract content that reflects real aspects of the universe. This of course is the position taken by hard-line constructivism, going back to Kant. Using the symbols and knowledge structures built up from this abstract content, we construct narratives of our experience, stored as memories, to better understand the outcome of events and, ultimately, the world around us (Pribram, 1994).

APPENDIX

A

Types of Links in Memory The following is a description of eight kinds of associative links in memory.

IDENTITY LINKS An identity link connects material of the same kind. If I think “rose,” the thought, a cue, will make contact with rose representations in the longterm store. The question, “What did I do yesterday morning?” will access information in long-term memory (LTM) corresponding to “yesterday morning.”

SIMILARITY LINKS Connection is made on the basis of similarity.

For instance, you might be at a gas station and see a woman you have never seen before.You next think of (remember) your niece. This is because the unknown woman and your niece are similar in appearance.

You will also normally become aware of the similarity relation.

CONTIGUITY LINKS A contiguity link forms between two or more elements experienced together. For instance, if you always see that orange cat in your neighbor’s yard, the sight of the yard is likely to remind you (make you recall) the cat.

It has not been established how broadly contiguity operates. For instance, are all the events of a dinner party linked in memory because they occurred in a sense together?

ORDER LINKS Order links indicate the order in which events occurred, or information occurred, or material is required to occur. Order links may underlie our ability to recite the alphabet, or to recall whether we first put the kettle on

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this morning and then put the dog out—or put the dog out first, etc. They may also underlie our ability to memorize language items (such as words, etc.) in order.

TEMPORAL LINKS A temporal link involves recalling events in the temporal order that they were originally experienced. Some psychologists today believe that some of the functions described under “order” may really involve temporal links.

For instance, recalling word items on a list could involve being cued by the time when each item was learned (Item 2 temporally after Item 1, etc.).

CAUSAL LINKS A causal link leads you to recall the outcome that follows, and is caused by, an event. Recalling the onset of a rainstorm will lead to a recollection of getting wet.

SUBSET/SUPERSET LINKS These involve a relation specifying of two constituents that one is a component or subset of the other. The one is related to the other as forming part of it, in an informational (not physical) sense. For instance, for the specification “Jane Eyre,” subset links connect this header specification with the content of the book or film. “What Happened at Breakfast” should involve subset links to the events of breakfast. The links appear to work in both directions, such that if you recall spilling your tea, the memory function is likely to establish that it happened at breakfast (subset → superset information).

PART/WHOLE LINKS These reflect relations between the parts and wholes of objects. If you activate the idea of a chair, the memory function can establish that it has legs and a back. These links probably operate in both directions, as with subset and superset. If the components of a chair are adequately described, the memory function can tell you that the object is a chair.

APPENDIX

B

Interference and Forgetting In its most basic form, our memory system provides us with access to information that enables us to perform our daily activities. We can draw on previously stored information in memory to hold a conversation, follow a route to work, order a favorite meal at a restaurant, recognize a familiar face in a crowd or a family member’s voice on the phone, sing a favorite song, and even reflect on our life’s experiences. Our memory system can also help us to retain new information such as a new procedure required of our job, a new restaurant we have discovered, a new friend we have just met, the melody and lyrics to a new song, or a new way of thinking about ourselves. In short, our memory system stores knowledge that is essential to the success of our everyday functioning and enables us to use this knowledge to not only learn from our experiences but also to enrich the quality of our lives.

Unfortunately, the operation of our memory system does not always help us. We sometimes forget information that was previously stored, as sometimes happens when taking an exam, or we have difficulty retaining new information, such as the name of a person we recently met. In these situations, our memory system fails us, but it is just these experiences that enrich our understanding of how memory works.

Memory theorists studying the process of forgetting have identified two general influences on the quality of our recollection: (1) factors outside of the person (i.e. external) such as the passage of time, the level of distraction present in the environment, or the form of the information to be remembered; and (2) factors within the memory system itself (i.e. internal) such as the relationship between a target item to be retrieved and its associates stored in memory. In the present section, we will discuss the latter of these influences on recollection in an effort to understand how the nature of the memory system itself contributes to memory failure.

The paradox of memory failure due to memory itself is known as interference. The general idea is that there is an interaction between previously stored information in the memory system and new information. In one of the earliest studies on interference, Jenkins and Dallenbach (1924) Human Memory, http://dx.doi.org/10.1016/B978-0-12-408087-4.00019-0

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found that people demonstrated higher levels of retention for information following a period of sleep than after the same period of time in an active, awake state. According to Jenkins and Dallenbach, the sleep period, by reducing memory activity, buffered the memory system from interference and thereby aided retention. Moreover, inactivity was theorized to benefit retention because it allowed neural activity to fix or consolidate the newly learned material into a more permanent representation in the memory system. The idea is that consolidated memories are less susceptible to interference. Importantly, Jenkins and Dellenbach’s early study demonstrated that forgetting is not simply the loss of content from memory, but can be due to the disruption of storage by the operation of the memory system itself.

While a period of inactivity tends to benefit the retention of new information, the quality of memory has also been found to depend on the interaction between incoming information and previously stored information.

Specifically, three forms of interference have been identified based on this interaction between memory and incoming information: negative transfer, proactive interference, and retroactive interference.

NEGATIVE TRANSFER In negative transfer, previously stored information in the memory system suppresses or blocks the acquisition of new information (Griffiths, Johnson, & Mitchell, 2011; Osgood, 1949). An example of negative transfer is when a person attempts to learn a new language later in life and has difficulty learning words in the new language that are similar, either in appearance or sound, to words in their native language. In these situations, attempts to retrieve a target word in the new language will activate similar words in the native language and thereby prevent successful retrieval of the target word. Impairment to learning due to negative transfer tends to be stronger in situations where the stimuli to be learned are similar and the responses required are different (Gibson, 1941; Runquist, 1969; Watson, 1938). Such impairments have even been implicated in workplace fatalities where a previously learned safety procedure conflicts with a newly adopted one (Besnard & Cascitti, 2005).

PROACTIVE INTERFERENCE Proactive interference is a form of interference in which information previously stored in the memory system disrupts memory for recently learned information (Underwood, 1948, 1949). In contrast to negative

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transfer, proactive interference results in the forgetting of information that has been recently stored in memory rather than disrupting the process of learning new information. Proactive interference is generally demonstrated using a paradigm in which participants learn two separate lists of words (List A and List B) in succession. When memory for the words on List B is tested, performance is found to be poorer for those participants who studied List B after learning List A, compared to another group of participants who only studied List B. The decline in memory performance for those who studied both List A and List B is attributed to the proactive interference generated by previously learning the words on List A. As with negative transfer, proactive interference is stronger when the information to be learned during successive sessions is semantically similar (Bunting, 2006; Keppel & Underwood, 1962; Postman & Keppel, 1977; Underwood, 1945; Underwood, 1983b). In fact, proactive interference has been shown to build up as one learns more information that is similar to previously learned information, a phenomenon known as the cue-overload effect (M. Watkins & O. Watkins, 1976; O. Watkins & M. Watkins, 1975). In these situations, retrieval of the learned material becomes progressively poorer with each exposure to information that is similar to what one has recently studied. In order to break this cycle, new material that is dissimilar to that previously studied must be presented. The resulting boost in memory performance due to the introduction of this new, dissimilar material is known as release from proactive interference (Wickens, Born, & Allen, 1963).

RETROACTIVE INTERFERENCE The phenomenon of retroactive interference is the direct opposite of proactive interference; it occurs when information that is most recently learned disrupts memory for previously learned information (Melton & Irwin, 1940). In sleep studies examining consolidation, the effects of retroactive interference are evident when the intervening activity period disrupts memory for the original learning episode (Ekstrand, 1967; Jenkins & Dallenbach, 1924; Yaroush, Sullivan, & Ekstrand, 1971; for reviews, see Paller & Voss, 2004; Wixted, 2010). In everyday life, retroactive interference can be observed when after learning a new e-mail password, we find that we can no longer recall our previous password. Studies have shown that retroactive interference effects are stronger than proactive interference effects (Melton & von Lackum, 1941), and that retroactive interference can be minimized through the use of postinformation cues indicating how

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items on the word lists are related (Bower & Mann, 1992; Gardiner, Craik, & Birtwistle, 1972; Marsh, Landau, & Hicks, 1996).

INTERFERENCE THEORY Explanations for the mechanisms responsible for interference center around two views of forgetting: response competition and the unlearning of associations. In the former view, interference is theorized to arise from competing sources of information in memory, with one source representing previously learned information and the other source representing recently learned information (McGeoch, 1942; Webb, 1917; for reviews, see Keppel, 1968; Postman, 1961; Postman & Underwood, 1973). The alternative view is that interference results from a process by which one set of associations becomes replaced by another set of associations and thus becomes unlearned. The unlearning theory is historically derived from Pavlov’s (1927) studies on conditioned learning in animals. Specifically, Pavlov found that the pairing of an initially neutral stimulus (e.g. a bell) with an unconditioned stimulus (e.g. food) led to a learned association between the bell and the food such that simply ringing the bell in the absence of food would produce the conditioned response, salivation. Through this process, the neutral stimulus acquires the ability to elicit the response in the absence of the food, and thus becomes the conditioned stimulus. Similarly, Pavlov found that the process of unlearning, or extinguishing the conditioned response, required a number of presentations of the bell without the delivery of the food. Over time, the conditioned response to the conditioned stimulus, presented by itself, is gradually weakened until it can no longer be elicited.

The unlearning hypothesis was tested using the paired-associate paradigm, in which participants learn a list of word pairs such that the words on List A are paired with the words on List B. After successfully learning these pairs, participants are given a new list of pairs, List C, to replace List B. Thus, in the first phase of the paired-associate paradigm, A-B learning occurs; in the second phase, A-C learning occurs. Importantly, the pairedassociate paradigm was meant to represent the Pavlovian process by which conditioning (A-B learning) and extinction (A-C learning, or relearning a new set of associates to the words on List A) took place.

Using the paired-associate paradigm, Briggs (1954) found that A-C learning resulted in the extinction of A-B learning consistent with the unlearning hypothesis. Briggs also found an interesting result: A-C learning became progressively worse as the retention interval between A-B learning

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and A-C testing increased. Specifically, participants gave increasingly more B responses during A-C testing as the retention interval lengthened. Briggs interpreted this pattern of responding as evidence for the operation of another Pavlovian concept, spontaneous recovery. In other words, the original conditioned response (A-B learning) undergoes an increase in strength during the retention interval and interferes with the new A-C learning.

While the primary result of Briggs’s (1954) study was that A-C learning extinguished the original A-B learning, it was not entirely clear whether this extinction was due to the unlearning of A-B associations or interference resulting from competition between A-B and A-C learning. In order to test these two explanations of interference, Barnes and Underwood (1959) replicated Briggs’s study and introduced the modified modified free recall test (MMFR) to eliminate the effect of response competition on learning. In the MMFR, during A-C testing, participants are asked to recall both associates to the A-list words. The requirement to recall both associates is theorized to eliminate competition from affecting the results. Using the MMFR, Barnes and Underwood found the same pattern of results as Briggs: A-C learning weakens A-B learning. Given that A-B learning recovers after a period of delay, Barnes and Underwood concluded that the interference effect, due to unlearning rather than competition, represents temporary inhibition of A-B learning.

Despite evidence for the operation of an unlearning mechanism in interference, there were some notable issues requiring further explanation.

For example, DaPolito (1967) found that there was no correlation between recall of B-list and C-list words. If interference were due to the operation of a temporary inhibitory mechanism on A-B learning, then a negative correlation would be expected between recall of B- and C-list words. Similarly, retroactive interference does not appear to depend on the degree of previous learning (Bäuml, 1996). Furthermore, a number of studies using the MMFR paradigm reported proactive interference in which A-B learning disrupts A-C learning, presumably through response competition since the unlearning mechanism would inhibit the effect of A-B learning (Ceraso & Henderson, 1965, 1966; Koppenaal, 1963). Finally, the finding that retroactive interference was reduced using a recognition test, compared to a recall test, could not be explained by an unlearning mechanism because such a mechanism should be expected to exert equal effects on both recall and recognition (Postman & Stark, 1969).

Interference theory accounts represented the dominant approach to forgetting in psychology from the 1940s to the 1970s. Thereafter, however,

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memory research began to change, first by incorporating new structural (Atkinson & Shiffrin, 1968) and procedural models of memory (Baddeley, 1986, 2000; Baddeley & Hitch, 1974), and then utilizing models based on the semantic organization of computer networks (Anderson, 1976, 1983a, 1990; Collins & Quillian, 1969, 1972) and findings from neuro­science (Baddeley, 1982; Squire, 1992). As a result, interest in the locus of inter­ ference effects shifted from temporal accounts to identifying interference within specific memory components in a chain of operations including encoding, representation, retrieval, and processing (Reyna & Mills, 2007). Along these lines, the effects of interference have been examined developmentally (Reyna & Brainerd, 1998) and in individuals with cognitive impairment (Reyna & Brainerd, 2004), as well as in cognitive processes that are closely linked with memory processes such as reasoning (Brainerd & Reyna, 2005; Reyna, 1995). Interference theory has also been enriched through applications to everyday memory phenomena. For example, Loftus’s (1979a, 1979b) research examining eyewitness memory changes, subsequent to exposure to misinformation, can be conceptualized as a specific form of retroactive interference. In summary, interference is less often studied with respect to retroactive interference and proactive interference in modern approaches to forgetting, but is an inherent feature of many models and theories exploring how information is represented in human memory.

REFERENCES REFERENCES Adolphs, R., Cahill, L., Schul, R., & Babinsky, R. (1997). Impaired declarative memory for emotional material following bilateral amygdala damage in humans. Learning and Memory, 4, 291–300.

Alaghband, Y., & Marshall, J. F. (2013). Common influences of noncompetitive NMDA receptor antagonists on the consolidation and reconsolidation of cocaine-cue memory.

Psychopharmacology, 226, 707–719.

Alba, J. W., & Hasher, L. (1983). Is memory schematic? Psychological Bulletin, 93(2), 203–231.

Albert, M. S., Butters, N., & Levin, J. (1979). Temporal gradients in the retrograde amnesia of patients with alcoholic Korsakoff ’s disease. Archives of Neurology, 36(4), 211–216.

Ally, B. A., Hussey, E. P., & Donohue, M. J. (2013). A case of hyperthymesia: Rethinking the role of the amygdala in autobiographical memory. Neurocase, 19, 166–181.

Amaral, D. G., Price, J. L., Pitkänen, A., & Carmichael, S. T. (1992). Anatomical organization of the primate amygdaloid complex. In J. P. Aggleton (Ed.), The amygdala: Neurobiological aspects of emotion, memory, and mental dysfunction (pp. 1–66). New York: Wiley-Liss.

Ammons, H., & Irion, A. I. (1954). A note on the Ballard reminiscence phenomenon. Journal of Experimental Psychology, 48, 184–186.

Anderson, A. K., & Phelps, E. A. (2001). Lesions of the human amygdala impair enhanced perception of emotionally salient events. Nature, 411, 305–309.

Anderson, J. R. (1976). Language, memory and thought. Hillsdale New Jersey: Lawrence Erlbaum Associates.

Anderson, J. R. (1981). Effects of prior knowledge on memory for new information. Memory and Cognition, 9, 237–246.

Anderson, J. R. (1983a). A spreading activation theory of memory. Journal Of Verbal Learning and Verbal Behavior, 22, 261–295.

Anderson, J. R. (1983b). The architecture of cognition. Cambridge, MA: Harvard University Press.

Anderson, J. R. (1989a). Practice, working memory, and the ACT theory of skill acquisition: A comment on Carlson, Sullivan, and Schneider (1989). Journal of Experimental Psychology: Learning, Memory, and Cognition, 15, 527–530.

Anderson, J. R. (1989b). A rational analysis of human memory. In H. L. Roediger III, & F. I. M. Craik (Eds.), Varieties of memory and consciousness: Essays in honor of Endel Tulving (pp.

195–210). Hillsdale, NJ: Lawrence Erlbaum Associates, Inc. Anderson, J. R. (1990). The adaptive character of thought. Hillsdale, NJ: Lawrence Erlbaum Associates, Inc. Anderson, J. R., Bothell, D., Byrne, M. D., Douglass, S., Lebiere, C., & Qin, Y. (2004). An integrated theory of the mind. Psychological Review, 111, 1036–1060.

Anderson, J. R., Bothell, D., Lebiere, C., & Matessa, M. (1998). An integrated theory of list memory. Journal of Memory and Language, 38, 341–380.

Anderson, J. R., & Bower, G. H. (1973). Human associative memory.Washington, D.C:Winston.

Anderson, J. R., & Matessa, M. (1997). A production system theory of serial memory.

Psychological Review, 104, 728–748.

Anderson, J. R., & Schooler, C. J. (1991). Reflections of the environment in memory.

Psychological Science, 2, 396–408.

Anderson, M. C., Bjork, D. A., & Bjork, E. L. (1994). Remembering can cause forgetting: Retrieval demands in long-term memory. Journal of Experimental Psychology: Learning, Memory and Cognition, 20, 1063–1087.

Human Memory, http://dx.doi.org/10.1016/B978-0-12-408087-4.00020-7

© 2014 Elsevier Inc. All rights reserved.

229

230

References

Anderson, R. C., Pichert, J. W., Goetz, E. T., Schallert, D. L., Stevens, K. V., & Trollip, S. R. (1976). Instantiation of general terms. Journal of Verbal Learning and Verbal Behavior, 15, 667–679.

Anderson, S. J., & Conway, M. A. (1993). Investigating the structure of specific autobiographical memories. Journal of Experimental Psychology: Learning, Memory and Cognition, 19, 1–19.

Aristotle (1961). De anima (On the soul). W. D. Ross (Ed.). Oxford, UK: Clarendon Press.

Arkes, H. R., Hackett, C., & Boehm, L. (1989).The generality of the relation between familiarity and judged validity. Journal of Behavioral Decision Making, 2, 81–94.

Arrigo, J. M., & Pezdek, K. (1997). Lessons from the study of psychogenic amnesia. Current Directions in Psychological Science, 6, 148–152.

Atkinson, R. C., & Shiffrin, R. M. (1968). Human memory: A proposed system and its control processes. In K. W. Spence, & J. T. Spence (Eds.), The psychology of learning and motivation: Advances in research and theory (Vol. 2, pp. 89–195). New York: Academic Press.

Auber, A., Tedesco, V., Jones, C. E., Monfils, M.-H., & Chiamulera, C. (2013). Post-retrieval extinction as reconsolidation interference: Methodological issues or boundary conditions? Psychopharmacology, 226, 631–647.

Bacon, F. T. (1979). Credibility of repeated statements: Memory for trivia. Journal of Experimental Psychology: Human Learning and Memory, 5, 241–252.

Baddeley, A. D. (1968). How does acoustic similarity influence short term memory? The Quarterly Journal of Experimental Psychology, 20, 249–263.

Baddeley, A. D. (1972). Selective attention and performance in dangerous environments.

British Journal of Psychology, 63, 537–546.

Baddeley, A. D. (1982). Implications of neuropsychological evidence for theories of normal memory. In D. E. Broadbent, & L. Wesikrantz (Eds.), Philosophical Transactions of the Royal Society of London (Vol. 298, pp. 59–72). London: The Royal Society.

Baddeley, A. D. (1986). Working Memory. New York: Oxford University Press.

Baddeley, A. D. (1990). Human memory: Theory and practice. Needham Heights, MA: Allyn & Bacon.

Baddeley, A. D. (2000). The episodic buffer: A new component of working memory? Trends in Cognitive Science, 4, 417–423.

Baddeley, A. D. (2002). Is working memory still working? European Psychologist, 7, 85–97.

Baddeley, A. D., Conrad, R., & Hull, A. J. (1965). Predictability and immediate memory for consonant sequences. The Quarterly Journal of Experimental Psychology, 17, 175–177.

Baddeley, A. D., & Hitch, G. (1974). Working memory. In G. H. Bower (Ed.), The psychology of learning and motivation (Vol. 8). New York: Academic Press.

Baddeley, A. D., & Logie, R. H. (1999). Working memory: The multi-component model. In A. Miyake, & P. Shah (Eds.), Models of working memory: Mechanisms of active maintenance and executive control (pp. 28–61). New York: Cambridge University Press.

Baddeley, A. D., & Wilson, B. A. (1986). Amnesia, autobiographical memory and confabulation. In D. C. Rubin (Ed.), Autobiographical memory (pp. 225–252). New York: Cambridge University Press.

Baillargeon, R., Spelke, E., & Wasserman, S. (1985). Object permanence in five-month-old infants. Cognition, 20, 191–208.

Ballard, P. B. (1913). Obliviscence and reminiscence. British Journal of Psychology, Monograph Supplement, 1, 1–82.

Barnes, J. M., & Underwood, B. J. (1959). Fate of first-list associations in transfer theory.

Journal of Experimental Psychology, 58, 97–105.

Barsalou, L. W. (1988). The content and organization of autobiographical memories. In U. Neisser, & E. Winograd (Eds.), Remembering reconsidered: Ecological and traditional approaches to the study of memory (pp. 193–243). New York: Cambridge University Press.

Human Memory: A Constructivist View

231

Bartlett, F. C. (1932). Remembering: A study in experimental and social psychology. Cambridge, UK: Cambridge University Press.

Battig, W. F., & Montague, W. E. (1969). Category norms of verbal items in 56 categories: A replication and extension of the Connecticut category norms. Journal of Experimental Psychology, 80(3, pt. 2), 1–46.

Bäuml, K.-H. (1996). Revisiting an old issue: Retroactive interference as a function of the degree of original and interpolated learning. Psychonomic Bulletin and Review, 3, 380–384.

Baxter, M. G., & Murray, E. A. (2000). Reinterpreting the behavioural effects of amygdala lesions in non-human primates. In J. Aggleton (Ed.), The amygdala: A functional analysis (pp. 545–568). Oxford: Oxford University Press.

Bekerian, D. A., & Bowers, J. M. (1983). Eyewitness testimony: Were we misled? Journal of Experimental Psychology: Learning, Memory, and Cognition, 9, 139–145.

Belli, R. F. (1989). Influences of misleading postevent information: Misinformation interference and acceptance. Journal of Experimental Psychology: General, 118, 72–85.

Belli, R. F. (1993). Failure of interpolated tests in inducing memory impairment with final modified tests: Evidence unfavorable to the blocking hypothesis. The American Journal of Psychology, 106, 407–427.

Belli, R. F., Lindsay, D. S., Gales, M. S., & McCarthy, T. T. (1994). Memory impairment and source misattribution in postevent misinformation experiments with short retention intervals. Memory & Cognition, 22, 40–54.

Belli, R. F., Windschitl, P. D., McCarthy, T. T., & Winfrey, S. E. (1992). Detecting memory impairment with a modified test procedure: Manipulating retention interval with centrally presented event items. Journal of Experimental Psychology: Learning, Memory and Cognition, 18, 356–367.

Benford, G. (1987). Great sky river. New York: Bantam Books.

Bergman, E. T., & Roediger, H. L. III, (1999). Can Bartlett’s repeated reproduction experiments be replicated? Memory and Cognition, 27, 937–947.

Besnard, D., & Cascitti, L. (2005). Interface changes causing accidents: An empirical study of negative transfer. International Journal of Human-Computer Studies, 62, 105–125.

Bjork, E. L., & Healy, A. F. (1974). Short-term order and item information. Journal of Verbal Learning and Verbal Behavior, 13, 80–97.

Blaney, P. H. (1986). Affect and memory: A review. Psychological Bulletin, 99, 229–246.

Bloom, L. (1970). Language development: Form and function in emerging grammars. MIT Research Monograph, No. 59.

Bluck, S., & Li, K. Z. H. (2001). Predicting memory completeness and accuracy: Emotion and exposure in repeated autobiographical recall. Applied Cognitive Psychology, 15, 145–158.

Boden, M. (1977). Artificial intelligence and natural man. New York: Basic Books.

Bohannon, J. N. (1988). Flashbulb memories for the space shuttle disaster: A tale of two theories. Cognition, 29, 179–196.

Bohannon, J. N., III & Symons, V. L. (1992). Flashbulb memories: Confidence, consistency, and quantity. In E. Winograd, & U. Neisser (Eds.), Affect and accuracy in recall: Studies of “flashbulb” memories (pp. 65–91). New York: Cambridge University Press.

Boller, K., Grabelle, M., & Rovee-Collier, C. (1995). Effects of postevent information on infants’ memory for a central target. Journal of Experimental Child Psychology, 59, 372–396.

Bonto, M. A., & Payne, D. G. (1991). Role of environmental context in eyewitness memory.

The American Journal of Psychology, 104, 117–134.

Bonvillian, J. D., Orlansky, M. D., & Novack, L. L. (1983). Early sign language acquisition and its relation to cognitive and motor development. In J. G. Kyle, & B.Woll (Eds.), Language in sign: International perspectives on sign language (pp. 116–125). London: Croom Helm.

232

References

Botvinick, M. M., & Plaut, D. C. (2006). Short term memory for serial order: A recurrent neural network model. Psychological Review, 113, 201–233.

Bousfield, W. A. (1951, September). Frequency and availability measures in language behavior. Paper presented at the Annual Meeting of the American Psychological Association, Chicago.

Bousfield, W. A. (1953). The occurrence of clustering in the recall of randomly arranged associates. Journal of General Psychology, 49, 229–240.

Bower, G. H. (1981). Mood and memory. American Psychologist, 36, 129–148.

Bower, G. H., & Clark, M. C. (1969). Narrative stories as mediators for serial learning.

Psychonomic Science, 14, 181–182.

Bower, G. H., & Mann, T. (1992). Improving recall by recoding interfering material at the time of retrieval. Journal of Experimental Psychology: Learning, Memory, and Cognition, 18, 1310–1320.

Bower, G. H., & Mayer, J. D. (1985). Failure to replicate mood-dependent retrieval. Bulletin of the Psychonomic Society, 23, 39–42.

Bowerman, M. (1973). Early syntactic development: A cross-linguistic study with special reference to Finnish. Oxford, UK: Cambridge University Press.

Brainerd, C. J., & Reyna,V. F. (2005). The science of false memory. New York: Oxford University Press.

Bransford, J. D., Barclay, R. J., & Franks, J. J. (1972). Sentence memory: A constructive versus interpretive approach. Cognitive Psychology, 3, 193–209.

Bransford, J. D., & Johnson, M. K. (1972). Contextual prerequisites for understanding: Some investigations of comprehension and recall. Journal of Verbal Learning and Verbal Behavior, 11, 717–726.

Bransford, J. D., & McCarrell, N. S. (1974). A sketch of a cognitive approach to comprehension: Some thoughts about understanding what it means to comprehend. In W. B. Weimer, & D. S. Palermo (Eds.), Cognition and the symbolic processes. Hillsdale, NJ: Lawrence Erlbaum.

Braun-LaTour, K. A., LaTour, M. S., Pickrell, J. E., & Loftus, E. F. (2004). How (and when) advertising can influence memory for consumer experience. Journal of Advertising, 33, 7–25.

Brewer,W. F. (1986).What is autobiographical memory? In D. C. Rubin (Ed.), Autobiographical memory (pp. 25–49). Cambridge, UK: Cambridge University Press.

Brewer, W. F. (1988). Memory for randomly sampled autobiographical events. In U. Neisser, & E. Winograd (Eds.), Remembering reconsidered: Ecological and traditional approaches to the study of memory (pp. 21–90). New York: Cambridge University Press.

Brewer, W. F. (1999). What is recollective memory? In D. C. Rubin (Ed.), Remembering our past (pp. 19–66). New York: Cambridge University Press.

Brewer, W. F., & Dupree, D. A. (1983). Use of plan schemata in the recall and recognition of goal-directed actions. Journal of Experimental Psychology: Learning, Memory, and Cognition, 9, 117–129.

Briggs, G. (1954). Acquisition, extinction and recovery functions in retroactive inhibition.

Journal of Experimental Psychology, 47, 285–293.

Broadbent, D. E. (1977). The hidden preattentive processes. American Psychologist, 32, 109–118.

Brown, A. L. (1973). Judgments of recency for long sequences of pictures: The absence of a developmental trend. Journal of Experimental Child Psychology, 15, 473–480.

Brown, G. D. A., Preece, T., & Hulme, C. (2000). Oscillator based memory for serial order.

Psychological Review, 107, 127–181.

Brown, G. D. A., & Vousden, J. I. (1998). Adaptive analysis of sequential behavior: Oscillators as rational mechanisms. In M. Oaksford, & N. Chater (Eds.), Rational models of cognition (pp. 165–193). Oxford, UK: Oxford University Press.

Human Memory: A Constructivist View

233

Brown, N. R., Shevell, S. K., & Rips, L. J. (1986). Public memories and their personal context. In D. C. Rubin (Ed.), Autobiographical memory (pp. 137–158). Cambridge, UK: Cambridge University Press.

Brown, R., & Kulik, J. (1977). Flashbulb memories. Cognition, 5, 73–99.

Bruhn, A. R. (1990). Earliest childhood memories: Vol. 1. Theory and application to clinical practice.

New York: Praeger Publishers.

Bruner, J. S. (1957). On perceptual readiness. Psychological Review, 64, 123–152.

Bruner, J. S., Goodnow, J. J., & Austin, G. A. (1956). A study of thinking. Oxford, UK: John Wiley & Sons.

Bruner, J. S., & Postman, L. (1948). Symbolic value as an organizing factor in perception.

Journal of Social Psychology, 27, 203–208.

Buchanan, T. W., & Adolphs, R. (2004). The neuroanatomy of emotional memory in humans. In D. Reisberg, & P. Hertel (Eds.), Memory and emotion (pp. 42–75). New York: Oxford University Press.

Bunting, M. (2006). Proactive interference and item similarity in working memory. Journal of Experimental Psychology: Learning, Memory, and Cognition, 32, 183–196.

Burgess, N. (1995). A solvable connectionist model of immediate recall of ordered lists. In G. Tesauro, D. S. Touretzky, & T. K. Leen (Eds.), Advances in neural information processing systems (Vol. 7, pp. 51–58). Cambridge, MA: MIT Press.

Burgess, N., & Hitch, G. J. (1992). Toward a network model of the articulatory loop. Journal of Memory and Language, 31, 429–460.

Burgess, N., & Hitch, G. J. (1999). Memory for serial order: A network model of the phonological loop and its timing. Psychological Review, 106, 551–581.

Burgess, N., & Hitch, G. J. (2006). A revised model of short-term memory and long-term learning of verbal sequences. Journal of Memory and Language, 55, 627–652.

Burgess, P. W., & Shallice, T. (1996). Confabulation and the control of recollection. Memory, 4, 359–411.

Burke, A., Heuer, F., & Reisberg, D. (1992). Remembering emotional events. Memory and Cognition, 20, 277–290.

Burt, C. D. B. (2008). Time, language, and autobiographical memory. Language Learning, 58, 123–141.

Burt, C. D. B., Kemp, S., & Conway, M. A. (2001). What happens if you retest autobiographical memory ten years on? Memory and Cognition, 29, 127–136.

Burt, C. D. B., Kemp, S., & Conway, M. A. (2003). Themes, events, and episodes in autobiographical memory. Memory and Cognition, 31, 317–325.

Burt, C. D. B., Kemp, S., & Conway, M. (2008). Ordering the components of autobiographical events. Acta Psychologica, 127, 36–45.

Burt, C. D. B., Kemp, S., Grady, J. M., & Conway, M. (2000). Ordering autobiographical experiences. Memory, 8, 323–332.

Butters, N. (1984). The clinical aspects of memory disorders: Contributions from experimental studies of amnesia and dementia. Journal of Clinical Neuropsychology, 6, 17–36.

Byrne, M. D., & Anderson, J. R. (2001). Serial modules in parallel: The psychological refractory period and perfect time-sharing. Psychological Review, 108, 847–869.

Cahill, L., Babinsky, R., Markowitsch, H. J., & McGaugh, J. L. (1995). The amygdala and emotional memory. Nature, 377, 295–296.

Cahill, L., Haier, R. J., White, N. S., Fallon, J., Kilpatrick, L., Lawrence, C., et al. (2001). Sexrelated differences in amygdala activity during emotionally influenced memory storage.

Neurobiology of Learning and Memory, 75, 1–9.

Cahill, L., Prins, B., Weber, M., & McGaugh, J. L. (1994). β-Adrenergic activation and memory for emotional events. Nature, 371, 702–704.

234

References

Canli, T., Zhao, Z., Brewer, J., Gabrieli, J. D. E., & Cahill, L. (2000). Event-related activation in the human amygdala associates with later memory for individual emotional response.

Journal of Neuroscience, 20, RC99.

Carmichael, L., Hogan, H. P., & Walter, A. A. (1932). An experimental study of the effect of language on the reproduction of visually perceived form. Journal of Experimental Psychology, 15, 73–86.

Ceci, S. J., Ross, D. R., & Toglia, M. P. (1987). Age differences in suggestibility: Narrowing the uncertainties. In S. J. Ceci, M. P. Toglia, & D. F. Ross (Eds.), Children’s eyewitness memory (pp. 79–91). New York: Springer.

Ceraso, J., & Henderson, A. (1965). Unavailability and associative loss in RI and PI. Journal of Experimental Psychology, 70, 300–303.

Ceraso, J., & Henderson, A. (1966). Unavailability and associative loss in RI and PI: A second try. Journal of Experimental Psychology, 72, 314–316.

Chan, J. C. K., Thomas, A. K., & Bulevich, J. B. (2009). Recalling a witnessed event increases eyewitness suggestibility: The reversed testing effect. Psychological Science, 20, 66–73.

Chandler, C. C. (1989). Specific retroactive interference in modified recognition tests: Evidence for an unknown cause of interference. Journal of Experimental Psychology: Learning, Memory, and Cognition, 15, 256–265.

Chandler, C. C. (1991). How memory for an event is influenced by related events: Interference in modified recognition tests. Journal of Experimental Psychology: Learning Memory and Cognition, 17, 115–125.

Chandler, C. C. (1992). Accessing related events increases retroactive interference in a matching recognition test. Journal of Experimental Psychology: Learning, Memory, and Cognition, 17, 115–125.

Chomsky, N. (1957). Syntactic structures. Oxford, UK: Mouton.

Christiaansen, R. E., & Ochalek, K. (1983). Editing misleading information from memory: Evidence for the coexistence of original and postevent information. Memory & Cognition, 11, 467–475.

Christiansen, S. Å. (1992). Emotional stress and eyewitness testimony: A critical review.

Psychological Bulletin, 112, 284–309.

Christiansen, S. Å., & Engelberg, E. (1999). Memory and emotional consistency: The MS Estonia ferry disaster. Memory, 7, 471–482.

Christiansen, S. Å., & Hubinette, B. (1993). Hands up! A study of witnesses’ emotional reactions and memories associated with bank robberies. Applied Cognitive Psychology, 7, 365–379.

Church, R. M., & Broadbent, H. A. (1990). Alternative representations of time, number and rate. Cognition, 37, 55–81.

Cohen, G. (2000). Hierarchical models in cognition: Do they have psychological reality?

European Journal of Cognitive Psychology, 12, 1–36.

Colgrove, F. W. (1899). Individual memories. American Journal of Psychology, 10, 228–255.

Collins, A. M., & Loftus, E. F. (1975). A spreading activation theory of semantic processing.

Psychological Review, 82, 407–428.

Collins, A. M., & Quillian, R. M. (1969). Retrieval time from semantic memory. Journal of Verbal Learning and Verbal Behavior, 8, 240–247.

Collins, A. M., & Quillian, R. M. (1972). Experiments on semantic memory and language comprehension. In G. Lee (Ed.), Cognition in learning and memory (pp. 117–147). Oxford, UK: John Wiley & Sons.

Conrad, R. (1960). Serial order intrusions in immediate memory. British Journal of Psychology, 51, 45–48.

Conrad, R. (1965). Order error in immediate recall of sequences. Journal of Verbal Learning and Verbal Behavior, 4, 161–169.

Human Memory: A Constructivist View

235

Conway, M. A. (1992). A structural model of autobiographical memory. In M. A. Conway, D. C. Rubin, H. Spinnler, & W. A. Wagenaar (Eds.), Theoretical perspectives on autobiographical memory (Vol. 65, pp. 167–193). Dordrecht, The Netherlands: Kluwer Academic.

Conway, M. A. (1995). Autobiographical knowledge and autobiographical memories. In D. C. Rubin (Ed.), Remembering our past: Studies in autobiographical memory (pp. 67–93). New York: Cambridge University Press.

Conway, M. A. (1996). Autobiographical memory. In E. L. Bjork, & R. A. Bjork (Eds.), Memory (pp. 165–194). San Diego, CA: Academic Press.

Conway, M. A. (2005). Memory and the self. Journal of Memory and Language, 53, 594–628.

Conway, M. A., & Bekerian, D. A. (1987). Organization in autobiographical memory. Memory & Cognition, 15, 119–132.

Conway, M. A., Collins, A. F., Gathercole, S. E., & Anderson, S. J. (1996). Recollections of true and false autobiographical memories. Journal of Experimental Psychology, General, 125, 69–95.

Conway, M. A., & Hague, S. (1999). Overshadowing the reminiscence bump: Memories of a struggle for independence. Journal of Adult Development, 6, 35–44.

Conway, M. A., & Pleydell-Pearce, C. W. (2000). The construction of autobiographical memories in the self-memory system. Psychological Review, 107, 261–288.

Criss, A. H., Malmberg, K. J., & Shiffrin, R. M. (2011). Output interference in recognition memory. Journal of Memory and Language, 64, 316–326.

Curran, V. H., & Robbins, T. W. (2013). Special issue on consolidation, reconsolidation and extinction. Psychopharmacology, 226, 627–629.

Dalla Barba, G. (1995). Consciousness and confabulation: Remembering another past. In R. Campbell, & M. A. Conway (Eds.), Broken memories: Case studies in memory impairment (pp. 101–114). Cambridge, MA: Blackwell Publishers, Inc. DaPolito, F. J. (1967). Proactive effects with independent retrieval of competing responses.

Dissertation Abstracts International, 27, 2522–2523.

Darwin, C. (1872/1998). The expression of the emotions in man and animals. Oxford; New York: Oxford University Press. de Vega, M. (1995). Backward updating of mental models during continuous reading of narratives. Journal of Experimental Psychology: Learning, Memory, and Cognition, 21, 373–385.

Deese, J. (1961). From the isolated verbal unit to connected discourse. In C. N. Cofer, & B. S. Musgrave (Eds.), Verbal learning and verbal behavior (pp. 11–41). New York: McGraw-Hill.

Deese, J. (1966). The structure of associations in language and thought. Oxford, UK: Johns Hopkins Press.

Dennis, S., Lee, M. D., & Kinnell, A. (2008). Bayesian analysis of recognition memory. Journal of Memory and Language, 59, 361–376.

Dodd, D. H., & Bradshaw, J. M. (1980). Leading questions and memory: Pragmatic constraints. Journal of Verbal Learning and Verbal Behavior, 19, 695–704.

Dong, T. (1972). Cued partial recall of categorized words. Journal of Experimental Psychology, 93, 123–129.

Doyère,V., Dębiec, J., Monfils, M.-H., Schafe, G. E., & LeDoux, J. E. (2007). Synapse-specific reconsolidation of distinct fear memories in the lateral amygdala. Nature Neuroscience, 10, 414–416.

Dudai, Y. (2004). The neurobiology of consolidations, or, how stable is the engram. Annual Review of Psychology, 55, 51–86.

Dudycha, G. J., & Dudycha, M. M. (1933). Some factors and characteristics of childhood memories. Child Development, 4, 265–278.

Eakin, D. K., Schreiber, T. A., & Sergent-Marshall, S. (2003). Misinformation effects in eyewitness memory: The presence and absence of memory impairment as a function of warning and misinformation accessibility. Journal of Experimental Psychology: Learning, Memory, and Cognition, 29, 813–825.

236

References

Ebbinghaus, H. (1885/1964). Memory: A contribution to experimental psychology (H. A. Ruger, Trans.). Toronto, Ontario, Canada: Dover.

Eichenbaum, H., & Cohen, N. J. (2001). From conditioning to conscious recollection: Memory systems of the brain. New York: Oxford University Press.

Ekstrand, B. R. (1967). Effect of sleep on memory. Journal of Experimental Psychology, 75, 64–72.

Ellis, A. W. (1980). Errors in speech and short-term memory: The effects of phonemic similarity and syllable position. Journal of Verbal Learning and Verbal Behavior, 19, 624–634.

Ellis, H. C. & Ashbrook, P. W. (1991). The “state” of mood and memory research: A selective review. In D. Kuiken (Ed.), Mood and memory. (Special Issue) Journal of Social Behavior and Personality, 4, 1–21.

Elman, J. L. (1990). Finding structure in time. Cognitive Science, 14, 179–211.

Er, N. (2003). A new flashbulb memory model applied to the Marmara earthquake. Applied Cognitive Psychology, 17, 503–517.

Erdelyi, M. H., & Becker, J. (1974). Hypermnesia for pictures: Incremental memory for pictures but not for words in multiple recall trials. Cognitive Psychology, 6, 159–171.

Estes, W. K. (1972). An associative basis for coding and organization in memory. In A. W. Melton, & E. Martin (Eds.), Coding processes in human memory (pp. 161–190).Washington, DC: Winston.

Estes,W. K. (1985). Memory for temporal information. In J. A. Michon, & J. L. Jackson (Eds.), Time, mind, and behavior (pp. 151–168). Berlin: Springer-Verlag.

Estes, W. K. (1997). Processes of memory loss, recovery and distortion. Psychological Review, 104, 148–169.

Eysenck, M. W., & Keane, M. T. (2010). Cognitive psychology: A student’s handbook (6th ed.).

New York: Psychology Press.

Fillmore, C. J. (1968). The case for case. In E. Bach, & R. T. Harms (Eds.), Universals in linguistic theory (pp. 1–88). New York: Holt, Rinehart, & Winston.

Fisher, R. P., & Craik, F. I. (1977). Interaction between encoding and retrieval operations in cued recall. Journal of Experimental Psychology: Human Learning and Memory, 3, 701–711.

Flexser, A. J., & Tulving, E. (1978). Retrieval independence in recognition and recall.

Psychological Review, 85, 153–171.

Fodor, J. A. (1975). The language of thought. New York: Thomas Y. Crowell.

Fodor, J. (1986). The modularity of mind. In Z. W. Pylyshyn, & W. Demopoulos (Eds.), Meaning and cognitive structure: Issues in the computational theory of mind (pp. 3–18).

Westport, CT: Ablex Publishing.

Frankel, F. H. (1994). The concept of flashbacks in historical perspective. International Journal of Clinical and Experimental Hypnosis, 42, 321–336.

Freud, S. (1916-1917/1963). Introductory lectures on psycho-analysis. In J. Strachey (Ed.), The standard edition of the complete psychological works of Sigmund Freud (Vol. 15–16, pp.

243–496). London: Hogarth Press.

Friedman,W. J. (1993). Memory for the time of past events. Psychological Bulletin, 113, 44–66.

Frost, O. (2000). The quality of false memory over time: Is memory for misinformation remembered or known? Psychonomic Bulletin and Review, 7, 531–536.

Gage, D. F., & Safer, M. A. (1985). Hemisphere differences in the mood state-dependent effect for recognition of emotional faces. Journal of Experimental Psychology: Learning, Memory, and Cognition, 11, 752–763.

Gallistel, C. R. (1990). The organization of learning. Cambridge, MA: MIT Press.

Galton, F. (1879). Psychometric experiments. Brain, 2, 149–162.

Gardiner, J. M., Craik, F. I., & Birtwistle, J. (1972). Retrieval cues and release from proactive inhibition. Journal of Verbal Learning and Verbal Behavior, 11, 778–783.

Human Memory: A Constructivist View

237

Gaskell, G. D., & Wright, D. B. (1997). Group differences in memory for a political event.

In J. W. Pennebaker, D. Paez, & B. Rimé (Eds.), Collective memory of political events: Social psychological perspectives (pp. 175–189). Hillsdale, NJ: Lawrence Erlbaum Associates, Inc. Gauld, A., & Stephenson, G. M. (1967). Some experiments relating to Bartlett’s theory of remembering. British Journal of Psychology, 58, 39–49.

Gernsbacher, M. A., Goldsmith, H. H., & Robertson, R. R. (1992). Do readers mentally represent characters’ emotional states? Cognition and Emotion, 6, 89–111.

Gibson, E. J. (1941). Retroactive inhibition as a function of degree of generalization between tasks. Journal of Experimental Psychology, 28, 93–115.

Gillund, G., & Shiffrin, R. M. (1984). A retrieval model for both recognition and recall.

Psychological Review, 91, 1–67.

Glanzer, M., & Cunitz, A. R. (1966). Two storage mechanisms in free recall. Journal of Verbal Learning and Verbal Behavior, 5, 351–360.

Glasspool, D. (2005). Modeling serial order in behavior: Evidence from performance slips.

In G. Houghton (Ed.), Connectionist models in cognitive psychology (pp. 241–270). Hove: Psychology Press.

Glenberg, A. M., Meyer, M., & Lindem, K. (1987). Mental models contribute to foregrounding during text comprehension. Journal of Memory and Language, 26, 69–83.

Godden, D. R., & Baddeley, A. D. (1975). Context dependent memory in two natural environments: On land and underwater. British Journal of Psychology, 66, 325–331.

Gold, P. E., & Van Buskirk, R. B. (1975). Facilitation of time dependent memory processes with posttrial epinephrine injections. Behavioral Biology, 13, 145–153.

Goodwin, D. W., Powell, B., Bremer, D., Hoine, H., & Stern, J. (1969). Alcohol and recall: State-dependent effects in man. Science, 163, 1358–1360.

Greene, E., Flynn, M. S., & Loftus, E. F. (1982). Inducing resistance to misleading information. Journal of Verbal Learning and Verbal Behavior, 21, 207–219.

Griffiths, O., Johnson, A. M., & Mitchell, C. J. (2011). Negative transfer in human associative learning. Psychological Science, 22, 1198–1204.

Griffiths, T. L., Canini, K. R., Sanborn, A. N., & Navarro, D. (2007). Unifying rational models of categorization via the hierarchical Dirichlet process. In D. S. McNamara, & J. G. Trafton (Eds.), Proceedings of the 29th annual conference of the Cognitive Science Society (pp.

323–328). Hillsdale, NJ: Erlbaum.

Haber, R. N., & Erdelyi, M. H. (1967). Emergence and recovery of initially unavailable perceptual material. Journal of Verbal Learning and Verbal Behavior, 6, 618–628.

Hacker, M. J. (1980). Speed and accuracy of recency judgments for events in short-term memory. Journal of Experimental Psychology: Human Learning and Memory, 6, 651–675.

Haenggi, D., Kintsch, W., & Gernsbacher, M. A. (1995). Spatial situation models and text comprehension. Discourse Processes, 19, 173–199.

Hamann, S. B., Cahill, L., McGaugh, J. L., & Squire, L. R. (1997). Intact enhancement of declarative memory for emotional material in amnesia. Learning and Memory, 4, 301–309.

Hamann, S. B., Ely, T. D., Grafton, S. T., & Kilts, C. D. (1999). Amygdala activity relating to enhanced memory for pleasant and aversive stimuli. Nature Neuroscience, 2, 289–293.

Harper, D. N., & Garry, M. (2000). Postevent cues bias recognition performance in pigeons.

Animal Learning and Behavior, 28, 59–67.

Hartley, T., & Houghton, G. (1996). A linguistically constrained model of short-term memory for nonwords. Journal of Memory and Language, 35, 1–31.

Hawkins, S. A., & Hoch, S. J. (1992). Low-involvement learning: Memory without evaluation. Journal of Consumer Research, 19, 212–225.

Healy, A. F. (1974). Separating item from order information in short-term memory. Journal of Verbal Learning and Verbal Behavior, 13, 644–655.

238

References

Heaps, C. M., & Nash, M. (2001). Comparing recollective experience in true and false autobiographical memories. Journal of Experimental Psychology, Learning, Memory and Cognition, 27, 920–930.

Henson, R. N. A. (1998). Short-term memory for serial order: The Start-End Model.

Cognitive Psychology, 36, 73–137.

Henson, R. N. A. (1999). Coding position in short-term memory. International Journal of Psychology, 34(5/6), 403–409.

Henson, R. N. A., Norris, D. G., Page, M. P. A., & Baddeley, A. D. (1996). Unchained memory: Error patterns rule out chaining models of immediate serial recall. Quarterly Journal of Experimental Psychology A: Human Experimental Psychology, 49, 80–115.

Heuer, F., & Reisberg, D. (1990). Vivid memories of emotional events: The accuracy of remembered minutiae. Memory & Cognition, 18, 496–506.

Hilgard, E. R. (1965). Hypnotic susceptibility. Oxford, UK: Harcourt, Brace and World.

Hintzman, D. L., Block, R. A., & Summers, J. J. (1973). Contextual associations and memory for serial position. Journal of Experimental Psychology, 97, 220–229.

Hirt, E. R., McDonald, H. E., & Markman, K. D. (1998). Expectancy effects in reconstructive memory: When the past is just what we expected. In S. J. Lynn, & K. M. McConkey (Eds.), Truth in memory (pp. 62–89). New York: Guilford Press.

Hitch, G. J., Burgess, N., Towse, J. N., & Culpin, V. (1996). Temporal grouping effects in immediate recall: A working memory analysis. Quarterly Journal of Experimental Psychology, 49, 116–139.

Hosch, H. M., & Bothwell, R. K. (1990). Arousal, description and identification accuracy of victims and bystanders. Journal of Social Behavior and Personality, 5, 481–488.

Houghton, G. (1990). The problem of serial order: a neural network model of sequence learning and recall. In R. Dale, C. Mellish, & M. Zock (Eds.), Current research in natural language generation (pp. 287–319). London: Academic Press.

Houghton, G., & Tipper, S. P. (1994). A model of inhibitory mechanisms in selective attention. In D. Dagenbach, & T. H. Carr (Eds.), Inhibitory processes in attention, memory, and language (pp. 53–112). San Diego, CA: Academic Press.

Howes, M. B. (1990). The Psychology of Human Cognition. New York: Pergamon Press.

Howes, M., Siegel, M., & Brown, F. (1993). Early childhood memories: Accuracy and affect.

Cognition, 47, 95–119.

Hume, D. (1739/1965). Essential works of David Hume. R. Cohen (Ed.). New York: Bantam.

Hunt, R. R. (2003). Two contributions of distinctive processing to accurate memory. Journal of Memory and Language, 48, 811–825.

Hunt, R. R. (2006). The concept of distinctiveness in memory research. In R. R. Hunt, & J. B. Worthen (Eds.), Distinctiveness and memory (pp. 3–25). New York: Oxford University Press.

Hyman, I. E., Jr. Husband, T. H., & Billings, F. J. (1995). False memories of childhood experiences. Applied Cognitive Psychology, 9, 181–197.

Jacoby, L. L. (1983). Perceptual enhancement: Persistent effects of an experience. Journal of Experimental Psychology: Learning, Memory, and Cognition, 9, 21–38.

Janet, P. (1904). L’amnesie et la dissociation de souvenirs par l’emotion. Journal de Psychologie, 1, 417–453.

Janet, P. (1911). L’État mental des hystériques. Paris: Félix Alcan.

Jaschinski, U., & Wentura, D. (2002). Misleading postevent information and working memory capacity: An individual differences approach to eyewitness memory. Applied Cognitive Psychology, 16, 223–231.

Jenkins, J. G., & Dallenbach, K. M. (1924). Obliviscence during sleep and waking. American Journal of Psychology, 35, 605–612.

Human Memory: A Constructivist View

239

Jenkins, J. J., & Russell, W. A. (1952). Associative clustering during recall. Journal of Abnormal and Social Psychology, 47, 818–821.

Johnson, M. (1987). The body in the mind: The bodily basis of meaning, imagination and reasoning.

Chicago: University of Chicago Press.

Johnson, M. K., Hashtroudi, S., & Lindsay, D. S. (1993). Source monitoring. Psychological Bulletin, 114(1), 3–28.

Johnson, M. K., Raye, C. L., Foley, H. J., & Foley, M. A. (1981). Cognitive operations and decision bias in reality monitoring. American Journal of Psychology, 94(1), 37–64.

Johnson-Laird, P. N. (1980). Mental models in cognitive science. Cognitive Science, 4(1), 71–115.

Jordan, M. I. (1986). Serial order: A parallel distributed processing approach (ICS Report 8604). San Diego: University of California, Institute for Cognitive Science.

Kahana, M. J. (1996). Associate retrieval processes in free recall. Memory and Cognition, 24, 103–109.

Kahneman, D. (1973). Attention and effort. Englewood Cliffs, NJ: Prentice Hall.

Kandel, E. R., & Squire, L. R. (2001). Neuroscience: Breaking down scientific barriers to the study of brain and mind. In A. R. Damasio, A. Harrington, J. Kagan, B. S. McEwen, H. Moss, & R. Shaikh (Eds.), Unity of knowledge: The convergence of natural and human science (pp. 118–135). New York: New York Academy of Sciences.

Kant, I. (1781/1965). Critique of pure reason (N.K. Smith, Trans.). New York: St. Martin’s.

Karpicke, J. D., & Roediger, H. L. III, (2008). The critical importance of retrieval for learning. Science, 319, 966–968.

Kensinger, E. A., Addis, D. R., & Atapattu, R. K. (2011). Amygdala activity at encoding corresponds with memory vividness and with memory for select episodic details.

Neuropsychologia, 49, 663–673.

Kensinger, E. A., Garoff-Eaton, R. J., & Schacter, D. L. (2007). How negative emotion enhances the visual specificity of a memory. Journal of Cognitive Neuroscience, 19, 1872–1887.

Kensinger, E. A., & Schacter, D. L. (2007). Remembering the specific visual details of presented objects: Neuroimaging evidence for effects of emotion. Neuropsychologia, 45, 2951–2962.

Keppel, G. (1968). Retroactive and proactive inhibition. In T. R. Dixon, & D. L. Horton (Eds.), Verbal behavior and general behavior theory (pp. 172–213). Englewood Cliffs, NJ: Prentice Hall.

Keppel, G., & Underwood, B. J. (1962). Proactive inhibition in short-term retention of single items. Journal of Verbal Learning and Verbal Behavior, 1, 153–161.

Kintsch, W. (1970). Learning, memory and conceptual processes. Oxford, UK: Wiley.

Kintsch, W. (1974). The representation of meaning in memory. Hillsdale, New Jersey: Lawrence Erlbaum.

Kintsch, W. (1992). A cognitive architecture for comprehension. In H. L. Pick Jr., P. W. van den Broek, & D. C. Knill (Eds.), Cognition: Conceptual and methodological issues (pp.

143–163). Washington, DC: American Psychological Association.

Kintsch, W. (1998). Comprehension: A paradigm for cognition. New York: Cambridge University Press.

Kintsch, W., & Buschke, H. (1969). Homophones and synonyms in short-term memory.

Journal of Experimental Psychology, 80, 403–407.

Kintsch, W., & Mross, E. F. (1985). Context effects in word identification. Journal of Memory and Language, 24, 336–349.

Kintsch, W., & van Dijk, T. A. (1978). Toward a model of text comprehension and production. Psychological Review, 85, 363–394.

Kintsch, W., Welsch, D., Schmalhofer, F., & Zimny, S. (1990). Sentence memory: A theoretical analysis. Journal of Memory and Language, 29, 133–159.

240

References

Kleinsmith, L. J., & Kaplan, S. (1964). Interaction of arousal and recall interval in nonsense syllable paired-associate learning. Journal of Experimental Psychology, 67, 124–126.

Kolstad, V. T. (1991, April). Understanding of containment in 5.5-month-old infants. Paper presented at the Biennial Meeting of the Society for Research in Child Development, Seattle, WA. Kopelman, M. D., Guinan, E. M., & Lewis, P. D. R. (1995). Delusional memory, confabulation and frontal lobe dysfunction: A case study in De Clérambault’s syndrome. Neurocase, 1, 71–77.

Koppenaal, R. J. (1963). Time changes in strengths of A-B, A-C lists: Spontaneous recovery?

Journal of Verbal Learning and Verbal Behavior, 2, 310–319.

Koriat, A. (2000). The feeling of knowing: Some metatheoretical implications for consciousness and control. Consciousness & Cognition, 9, 149–171.

Koriat, A., & Goldsmith, M. (1994). Memory in naturalistic and laboratory contexts: Distinguishing the accuracy-oriented and the quality-oriented approaches to memory assessment. Journal of Experimental Psychology: General, 123, 297–315.

Kosslyn, S. M. (1994). Image and brain: The resolution of the imagery debate. Cambridge, MA: The MIT Press.

Kosslyn, S. M. (2005). Mental images and the brain. Cognitive Neuropsychology, 22, 333–347.

Kosslyn, S. M. (2006). You can play 20 questions with nature and win: Categorical versus coordinate spatial relations as a case study. Neuropsychologia, 44, 1519–1523.

Kosslyn, S. M., Ball, T. M., & Reiser, B. J. (1978).Visual images preserve metric spatial information: Evidence from studies of image scanning. Journal of Experimental Psychology: Human Perception and Performance, 4, 47–60.

Kosslyn, S. M., & Pomerantz, J. R. (1977). Imagery, propositions, and the form of internal representations. Cognitive Psychology, 9, 52–76.

Kosslyn, S. M., Thompson, W. L., Sukel, K. E., & Alpert, N. M. (2005). Two types of image generation: Evidence from PET. Cognitive, Affective, & Behavioral Neuroscience, 5, 41–53.

Kramer, T. H. (1984). The effects of weapon focus and arousal on eyewitness recall. Doctoral dissertation, City University of New York. Available as Center Monograph No. CR-61, Center for Responsive Psychology, Brooklyn College, Brooklyn, NY 11210.

Kramer, T. H., Buckhout, R., & Eugenio, P. (1990). Weapon focus, arousal, and eyewitness memory: Attention must be paid. Law and Human Behavior, 14, 167–184.

Kramer, T. H., Buckhout, R., Fox, P., Widman, E., & Tusche, B. (1991). Effects of stress on recall. Applied Cognitive Psychology, 5, 483–488.

Krystal, J. H., Southwick, S. M., & Charney, D. S. (1995). Post traumatic stress disorder: Psychobiological mechanisms of traumatic remembrance. In D. L. Schacter (Ed.), Memory distortions: How minds, brains, and societies reconstruct the past (pp. 150–172).

Cambridge, MA: Harvard University Press.

Kucera, H., & Francis, W. N. (1967). Computational analysis of present-day American English.

Providence, RI: Brown University Press.

Kuehn, L. L. (1974). Looking down a gun barrel: Person perception and violent crime.

Perceptual and Motor Skills, 39, 1159–1164.

Lakoff, G. (1987). Cognitive models and prototype theory. In U. Neisser (Ed.), Concepts and conceptual development: Ecological and intellectual factors in categorization (pp. 63–100). New York: Cambridge University Press.

Lampinen, J. M., & Smith, V. L. (1995). The incredible (and sometimes incredulous child witness): Child eyewitnesses’ sensitivity to source credibility cues. Journal of Applied Psychology, 80, 621–627.

Laney, C., Heuer, F., & Reisberg, D. (2005). Thematically-induced arousal in naturallyoccurring emotional memories. Applied Cognitive Psychology, 17, 995–1004.

Human Memory: A Constructivist View

241

Langacker, R. W. (1987). Foundations of cognitive grammar (Vol. 1). Stanford, CA: Stanford University Press.

Larson, S. F. (1992). Personal context in autobiographical and narrative memories. In M. A. Conway, D. C. Rubin, H. Spinnler, & W. A. Wagenaar (Eds.), Behavioral and social sciences (pp. 53–74).Theoretical perspectives on autobiographical memory (Vol. 65). Dordrecht, The Netherlands: Kluwer Academic.

Lashley, K. S. (1951). The problem of serial order in behavior. In L. A. Jeffress (Ed.), Cerebral mechanisms in behavior; the Hixon Symposium (pp. 112–136). Oxford, UK: Wiley.

LeDoux, J. E. (2000). Emotion circuits in the brain. Annual Review of Neuroscience, 23, 155–184.

Lee, C. L. (1992). The perturbation model of short-term memory: A review and some further developments. In A. F. Healy, S. M. Kosslyn, & R. M. Shiffrin (Eds.), Essays in honor of William K. Estes, Vol. 1: From learning theory to connectionist theory; Vol. 2: From learning processes to cognitive processes (pp. 119–141). Hillsdale, NJ: Lawrence Erlbaum Associates, Inc. Lee, C. L., & Estes, W. K. (1977). Order and position in primary memory for letter strings.

Journal of Verbal Learning & Verbal Memory, 16, 395–418.

Lee, C. L., & Estes, W. K. (1981). Item and order information in short-term memory: Evidence for multilevel perturbation processes. Journal of Experimental Psychology: Human Learning and Memory, 7, 149–169.

Lee, P. J., & Brown, N. R. (2003). Delay related changes in personal memories for September 11, 2001. Applied Cognitive Psychology, 17, 1007–1015.

Leslie, A. M. (1982). The perception of causality in infants. Perception, 11, 173–186.

Leslie, A. M. (1984). Spatiotemporal continuity and the perception of causality in infants.

Perception, 13, 287–305.

Lewandowsky, S., & Murdock, B. B. Jr., (1989). Memory for serial order. Psychological Review, 96, 25–57.

Libkuman, T. M., Nichols-Whitehead, P., Griffith, J., & Thomas, R. (1999). Source of arousal and memory for detail. Memory & Cognition, 27, 166–190.

Lindsay, D. S. (1990). Misleading suggestions can impair eyewitnesses’ ability to remember event details. Journal of Experimental Psychology, Learning, Memory and Cognition, 16, 1077–1083.

Lindsay, D. S., Hagen, L., Read, J. D., Wade, K. A., & Garry, M. (2004). True photographs and false memories. Psychological Science, 15, 149–154.

Lindsay, D. S., & Johnson, M. K. (1989). The eyewitness suggestibility effect and memory for source. Memory & Cognition, 17, 349–358.

Lindsay, D. S., & Read, J. D. (2006). Adults’ memories of long-past events. In L.-G. Nilsson, & N. Ohta (Eds.), Memory and society: Psychological perspectives (pp. 51–72). New York: Psychology Press.

Linton, M. (1975). Memory for real-world events. In D. A. Norman, & D. E. Rumelhart (Eds.), Explorations in cognition (pp. 376–404). San Francisco: W. H. Freeman.

Linton, M. (1979). Real-world memory after six years: An in vivo study of very long-term memory. In M. M. Gruneberg, P. E. Morris, & R. N. Sykes (Eds.), Practical aspects of memory (pp. 67–76). London: Academic Press.

Linton, M. (1986). Ways of searching and the contents of memory. In D. C. Rubin (Ed.), Autobiographical memory (pp. 50–67). New York: Cambridge University Press.

Linton, S. J., & Melin, L. (1982). The accuracy of remembering chronic pain. Pain, 13, 281–285.

Locke, J. (1690/1956). An essay concerning human understanding. Chicago: Henry Regnery.

Loftus, E. F. (1977). Shifting human color memory. Memory & Cognition, 5, 696–699.

242

References

Loftus, E. F. (1979a). Reactions to blatantly contradictory information. Memory & Cognition, 7, 368–374.

Loftus, E. F. (1979b). Eyewitness testimony. Cambridge, MA: Harvard University Press.

Loftus, E. F. (1993). The reality of repressed memories. American Psychologist, 48, 518–537.

Loftus, E. F. (1997). Creating false memories. Scientific American, 277(3), 70–75.

Loftus, E. F. (2004). Memories of things unseen. Current Directions in Psychological Science, 13(4), 145–147.

Loftus, E. F., Altman, D., & Geballe, R. (1975). Effects of questioning upon a witness’ later recollections. Journal of Police Science and Administration, 3(2), 162–165.

Loftus, E. F., Feldman, J., & Dashiell, R. (1995). The reality of illusory memories. In D. Schacter (Ed.), Memory distortions: How minds, brains, and societies reconstruct the past (pp.

47–68). Cambridge, MA: Harvard University Press.

Loftus, E. F., & Hoffman, H. G. (1989). Misinformation and memory: The creation of new memories. Journal of Experimental Psychology: General, 118, 100–104.

Loftus, E. F., & Ketcham, K. (1994). The myth of repressed memory: False memories and allegations of sexual abuse. New York: St. Martin’s.

Loftus, E. F., & Loftus, G. R. (1980). On the permanence of stored information in the human brain. American Psychologist, 35, 409–420.

Loftus, E. F., Loftus, G. R., & Messo, J. (1987). Some facts about “weapon focus”. Law and Human Behavior, 11, 55–62.

Loftus, E. F., Miller, D. G., & Burns, H. J. (1978). Semantic integration of verbal information into a visual memory. Journal of Experimental Psychology: Human Learning and Memory, 4, 19–31.

Loftus, E. F., & Pickrell, J. E. (1995). The formation of false memories. Psychiatric Annals, 25(12), 720–725.

Lorenz, K. (1963). On aggression. New York: Harcourt, Brace, and World.

Love, B. C., Medin, D. L., & Gureckis, T. M. (2004). SUSTAIN: A network model of category learning. Psychological Review, 111, 309–332.

Lovibond, P. F., & Shanks, D. R. (2002). The role of awareness in Pavlovian conditioning: Empirical evidence and theoretical implications. Journal of Experimental Psychology: Animal Behavior Processes, 28, 3–26.

Maass, K., & Köhnken, G. (1989). Eyewitness identification: Simulating the “weapon effect”.

Law and Human Behavior, 13, 397–408.

MacLeod, M. D., & Saunders, J. (2008). Retrieval inhibition and memory distortion: Negative consequences of an adaptive process. Current Directions in Psychological Science, 17, 26–30.

Malmberg, K. J., Criss, A. H., Gangwani, T. H., & Shiffrin, R. M. (2012). Overcoming the negative consequences of interference from recognition memory testing. Psychological Science, 23, 115–119.

Mandler, J. M. (1988). How to build a baby: On the development of an accessible representational system. Cognitive Development, 3, 113–136.

Mandler, J. M. (1992). How to build a baby II: Conceptual primitives. Psychological Review, 99, 587–604.

Mandler, J. M. (2000). Perceptual and conceptual processes in infancy. Journal of Cognition and Development, 1, 3–36.

Mandler, J. M., & Bauer, P. J. (1988). The cradle of categorization: Is the basic level basic?

Cognitive Development, 3, 247–264.

Mandler, J. M., & Johnson, N. S. (1977). Remembrance of things parsed: Story structure and recall. Cognitive Psychology, 9, 111–151.

Mandler, J. M., & McDonough, L. (1993). Concept formation in infancy. Cognitive Development, 8, 291–318.

Mandler, J. M., & McDonough, L. (1998). On developing a knowledge base in infancy.

Developmental Psychology, 34, 1274–1288.

Markowitsch, H. J., Calabrese, P., Würker, M., Durwen, H. F., Kessler, J., Babinsky, R., Brechtelsbauer, D., Heuser, L., & Gehlen, W. (1994). The amygdala’s contribution

Human Memory: A Constructivist View

243

to memory: A study on two patients with Urbach-Wiethe disease. Neuroreport: An International Journal for the Rapid Communication of Research in Neuroscience, 5, 1349–1352.

Markowitsch, H. J., Thiel, A., Reinkemeier, M., Kessler, J., Koyuncu, A., & Wolf-Dieter, H. (2000). Right amygdalar and temporofrontal activation during autobiographic, but not during fictitious memory retrieval. Behavioural Neurology, 12, 181–190.

Markus, H., & Nurius, P. (1986). Possible selves. American Psychologist, 41, 954–969.

Marr, D. (1982). Vision: A computational investigation into the human representation and processing of visual information. New York: W. H. Freeman.

Marsh, R. L., Landau, J. D., & Hicks, J. L. (1996). The postinformation effect and reductions in retroactive interference. Journal of Experimental Psychology: Learning, Memory, and Cognition, 22, 1296–1303.

McAdams, D. P. (1993). Stories we live by: Personal myths and the making of the self. New York: William Morrow & Co. McAdams, D. P., Diamond, A., de St. Aubin, E., & Mansfield, E. (1997). Stories of commitment: The psychosocial construction of generative lives. Journal of Personality and Social Psychology, 72, 678–694.

McClelland, J. L. (2000). Constructive memory and memory distortions: A parallel-distributed processing approach. In D. L. Schacter (Ed.), Memory distortions: How minds, brains, and societies reconstruct the past (pp. 69–90). Cambridge MA: Harvard University Press.

McClelland, J. L., & Rumelhart, D. E. (1986). Parallel-distributed processing: Explorations in the microstructure of cognition (Vol. 1). Cambridge, MA: MIT Press.

McCloskey, M., & Zaragoza, M. (1985). Misleading postevent information and memory for events: Arguments and evidence against memory impairment hypotheses. Journal of Experimental Psychology: General, 114, 1–16.

McConkey, K. M. (1992). The effects of hypnotic procedures on remembering: The experimental findings and their implications for forensic hypnosis. In E. Fromm, & M. R. Nash (Eds.), Contemporary hypnosis research (pp. 405–426). New York: Guilford Press.

McConkey, K. M., Labelle, L., Bibb, B. C., & Bryant, R. A. (1990). Hypnosis and suggested pseudomemory: The relevance of test context. Australian Journal of Psychology, 42, 197–205.

McCurdy, J. T. (1918). War neuroses. Cambridge, UK: Cambridge University Press.

McGaugh, J. L. (2000). Memory: A century of consolidation. Science, 287, 248–251.

McGaugh, J. L. (2004). The amygdala modulates the consolidation of memories of emotionally arousing experiences. Annual Review of Neuroscience, 27, 1–28.

McGeoch, J. A. (1932). Forgetting and the law of disuse. Psychological Review, 39, 352–370.

McGeoch, J. A. (1942). The psychology of human learning. Oxford, UK: Longmans.

McKoon, G., & Ratcliff, R. (1989). Inferences about contextually defined categories. Journal of Experimental Psychology: Learning, Memory, and Cognition, 15, 1134–1146.

McKoon, G., & Ratcliff, R. (1992). Spreading activation versus compound cue accounts of priming: Mediated priming revisited. Journal of Experimental Psychology: Learning Memory and Cognition, 18, 1155–1172.

McNally, R. J., Clancy, S. A., & Barrett, H. M. (2004). Forgetting trauma? In D. Resiberg, & P. Hertel (Eds.), Memory and emotion (pp. 129–154). New York: Oxford University Press.

McNally, R. J., Lasko, N. B., Clancy, S. A., Macklin, M. L., Pitman, R. K., & Orr, S. P. (2004).

Psychophysiological responding during script-driven imagery in people reporting abduction by space aliens. Psychological Science, 15, 493–497.

Melton, A. W., & Irwin, J. M. (1940). The influence of degree of interpolated learning on retroactive inhibition and the overt transfer of specific response. American Journal of Psychology, 53, 173–203.

Melton, A.W., & von Lackum,W. J. (1941). Retroactive and proactive inhibition in retention: Evidence for a two-factor theory of retroactive inhibition. American Journal of Psychology, 54, 157–173.

Mervis, C. B., & Rosch, E. (1981). Categorization of natural objects. Annual Review of Psychology, 32, 89–115.

244

References

Miller, G. A. (1956). The magical number seven, plus or minus two: Some limits on our capacity for processing information. Psychological Review, 63, 81–97.

Mitchell, C. J., DeHouwer, J., & Lovibond, P. F. (2009). The propositional nature of human associative learning. Behavioral and Brain Sciences, 32, 183–198.

Mori, N. (2008). Styles of remembering and types of experience: An experimental investigation of reconstructive memory. Integrative Psychological & Behavioral Science, 42, 291–314.

Moscovitch, M. (1989). Confabulation and the frontal systems: Strategic versus associative retrieval in neuropsychological theories of memory. In H. L. Roediger III, & F. I. M. Craik (Eds.), Varieties of memory and consciousness: Essays in honor of Endel Tulving (pp.

133–160). Hillsdale, NJ: Lawrence Erlbaum Associates, Inc. Moscovitch, M. (1992). A neuropsychological model of memory and consciousness. In L. R. Squire, & N. Butters (Eds.), Neuropsychology of memory (pp. 5–22). (2nd ed.) New York: Guilford Press.

Moscovitch, M., & Melo, B. (1997). Strategic retrieval and the frontal lobes: Evidence from confabulation and amnesia. Neuropsychologia, 35, 1017–1034.

Murdock, B. B. Jr., (1962). The serial position effect of free recall. Journal of Experimental Psychology, 64, 482–488.

Murdock, B. B. Jr., (1995). Developing TODAM: Three models for serial-order information.

Memory & Cognition, 23, 631–645.

Murphy, G. L. (1991). Parts in object concepts: Experiments with artificial categories.

Memory & Cognition, 19, 423–438.

Nairne, J. S. (1991). Positional uncertainty in long-term memory. Memory & Cognition, 19, 332–340.

Nairne, J. S. (2001). A functional analysis of primary memory. In H. L. Roediger III, J. S. Nairne, I. Neath, & A. Surprenant (Eds.), The nature of remembering: Essays in honor of Robert G. Crowder (pp. 283–296). Washington, DC: American Psychological Association.

Nairne, J. S. (2002a). Remembering over the short term: The case against the standard model. Annual Review of Psychology, 53, 53–81.

Nairne, J. S. (2002b). The myth of the encoding-retrieval match. Memory, 10, 389–395.

Nairne, J. S. (2006). Modeling distinctiveness: Implications for general memory theory. In H. R. Reed, & J. B. Worthen (Eds.), Distinctiveness and memory (pp. 27–46). New York: Oxford University Press.

Nash, M. (1987). What, if anything, is regressed about hypnotic age regression? A review of the empirical literature. Psychological Bulletin, 102, 42–52.

Neisser, U. (1982). Snapshots or benchmarks. In U. Neisser (Ed.), Memory observed (pp.

43–48). San Francisco: W. H. Freeman.

Neisser, U. (1986). Nested structure in autobiographical memory. In D. C. Rubin (Ed.), Autobiographical memory (pp. 71–81). New York: Cambridge University Press.

Neisser, U., & Harsch, N. (1992). Phantom flashbulbs: False recollections of hearing the news about Challenger. In E. Winograd, & U. Neisser (Eds.), Affect and accuracy in recall: Studies of “flashbulb” memories (pp. 9–31). New York: Cambridge University Press.

Nelson, D. L., & Brooks, D. H. (1974). Relative effectiveness of rhymes and synonyms as retrieval cues. Journal of Experimental Psychology, 102, 503–507.

Nelson, D. L., & McEvoy, C. L. (2002). How can the same type of prior knowledge both help and hinder recall? Journal of Memory and Language, 46, 652–663.

Nelson, K. (1993). Explaining the emergence of autobiographical memory in early childhood. In A. F. Collins, S. E. Gathercole, M. A. Conway, & P. E. Morris (Eds.), Theories of memory (pp. 355–385). Hillsdale, NJ: Lawrence Erlabum Associates, Inc. Newport, E. L., & Meier, R. P. (1985). The acquisition of American Sign Language. In D. I. Slobin (Ed.), The cross-linguistic study of language acquisition (pp. 881–938).Vol. 1: The data, Vol. 2: Theoretical issues. Hillsdale, NJ: Lawrence Erlbaum Associates, Inc. Newtson, D. (1976).The perceptual organization of ongoing behavior. Journal of Experimental Social Psychology, 12, 436–450.

Human Memory: A Constructivist View

245

Nickerson, R. S., & Adams, M. J. (1979). Long-term memory for a common object. Cognitive Psychology, 11, 287–307.

Noble, C. E. (1952). An analysis of meaning. Psychological Review, 59, 421–430.

Norman, D. A., & Bobrow, D. G. (1979). Descriptions: An intermediate stage in memory retrieval. Cognitive Psychology, 11, 107–123.

Nourkova,V., Bernstein, D. M., & Loftus, E. F. (2004). Altering traumatic memory. Cognition and Emotion, 18, 575–585. Öhman, A., & Mineka, S. (2001). Fears, phobias, and preparedness: Toward an evolved module of fear and fear learning. Psychological Review, 108, 483–522.

Orne, M. T. (1962). Hypnotically induced hallucinations. In J. L. West (Ed.), Hallucinations (pp. 211–219). Oxford, UK: Grune & Stratton.

Osgood, C. E. (1949). The similarity paradox in human learning: A resolution. Psychological Review, 56, 132–143.

Osherson, D. N., Smith, E. E., Wilkie, O., Lopez, A., & Shafir, E. (1990). Category-based induction. Psychological Review, 97, 185–200.

Ost, J., Foster, S., Costall, A., & Bull, R. (2005). False reports of childhood events in appropriate interviews. Memory, 13, 700–710.

Ozubko, J. D., & Fugelsang, J. (2011). Remembering makes evidence compelling: Retrieval from memory can give rise to the illusion of truth. Journal of Experimental Psychology, Learning Memory and Cognition, 37, 270–276.

Packard, M. G., & Teather, L. A. (1998). Amygdala modulation of multiple memory systems: Hippocampus and caudate-putamen. Neurobiology of Learning and Memory, 69, 163–203.

Page, M. P., & Norris, D. (1998). The primacy model: A new model of immediate serial recall. Psychological Review, 105, 761–781.

Paivio, A. (1969). Mental imagery in associative learning and memory. Psychological Review, 76(3), 241–263.

Paivio, A. (1991). Dual coding theory: Retrospect and current status. Canadian Journal of Psychology, 45(3), 255–287.

Paller, K. A., & Voss, J. L. (2004). Memory reactivation and consolidation during sleep.

Learning and Memory, 11, 664–670.

Pansky, A., & Koriat, A. (2004). The basic-level convergence effect in memory distortions.

Psychological Science, 15, 52–59.

Pansky, A., Tenenboim, E., & Bar, S. K. (2011). The misinformation effect revisited: Interactions between spontaneous memory processes and misleading suggestions. Journal of Memory and Language, 64, 270–287.

Parkin, A. J. (1987). Memory and amnesia: An introduction. Cambridge, MA: Basil Blackwell.

Parton, D. A., & Denike, D. L. (1966). Performance hypotheses of children and response to social reinforcement. Journal of Personality and Social Psychology, 4, 444–447.

Pavlov, I. (1927). Conditioned reflexes. London and New York: Oxford University Press.

Payne, D. G., Toglia, M. P., & Anastasi, J. S. (1994). Recognition performance level and the magnitude of the misinformation effect in eyewitness memory. Psychonomic Bulletin and Review, 1, 376–382.

Payne, J. D., Nadel, L., Britton, W. B., & Jacobs, W. J. (2004). The biopsychology of trauma and memory. In D. Reisberg, & P. Hertel (Eds.), Memory and emotion (pp. 76–128). New York: Oxford University Press.

Perruchet, P. (1985). Expectancy for airpuff and conditioned eyeblinks in humans. Acta Psychologica, 58, 31–44.

Perry, C. W., Laurence, J.-R., D’Eon, J., & Tallant, B. (1988). Hypnotic age regression techniques in the elicitation of memories: Applied uses and abuses. In H. M. Pettinati (Ed.), Hypnosis and memory (pp. 128–154). New York: Guilford Press.

Peters, D. P. (1988). Eyewitness memory and arousal in a natural setting. In M. M. Gruneberg, P. E. Morris, & R. N. Sykes (Eds.), Practical aspects of memory: Current research and issues (Vol. 1, pp. 89–94). Memory in everyday life. Chichester, UK: Wiley.

246

References

Piaget, J. (1926a). Judgment and reasoning in the child (M. Warden, Trans.). New York: Harcourt, Brace & World.

Piaget, J. (1926b). The language and thought of the child. Oxford, UK: Harcourt, Brace, & World.

Piaget, J. (1951). Play, dreams and imitation in childhood (C. Gategno & F. M. Hodgson, Trans.).

New York: W.W. Norton.

Piaget, J. (1952). The origins of intelligence in children (M. Cook, Trans.). New York: Basic Books.

Piaget, J. (1954). The construction of reality in the child (M. Cook, Trans.). New York: Basic Books.

Piaget, J. (1969). The mechanisms of perception (G. N. Seagrim, Trans.). London: Routledge & Kegan Paul.

Piaget, J. (1972). Intellectual evolution from adolescence to adulthood. Human Development, 15, 1–12.

Piaget, J. (1977). The development of thought: Equilibration of cognitive structures (A. Rosin, Trans.). Oxford, UK: Viking.

Piaget, J., & Inhelder, B. (1971). Mental imagery in the child: A study of the development of imaginal representation (P.A. Chilton, Trans.). New York: Basic Books, Inc. Piaget, J., & Inhelder, B. (1973). Memory and intelligence (A. J. Pomerans, Trans.). New York: Basic Books, Inc. Pitkänen, A., & Amaral, D. G. (1994). The distribution of GABAergic cells, fibers, and terminals in the monkey amygdaloid complex: An immunohistochemical and in situ hybridization study. Journal of Neuroscience, 14, 2200–2224.

Poirier, M., Nairne, J. S., Morin, C., Zimmerman, F. G. S., Koutmeridou, K., & Fowler, J. (2012). Memory as discrimination: A challenge to the encoding-retrieval match principle. Journal of Experimental Psychology: Learning, Memory, and Cognition, 38, 16–29.

Porter, S.,Yuille, J. C., & Lehman, D. R. (1999). The nature of real, implanted, and fabricated memories for emotional childhood events: Implications for the recovered memory debate. Law and Human Behavior, 23, 517–537.

Postman, L. (1961). The present status of interference theory. In C. N. Cofer (Ed.), Verbal learning and verbal behavior (pp. 152–179). New York: McGraw-Hill.

Postman, L., & Keppel, G. (1977). Conditions of cumulative proactive inhibition. Journal of Experimental Psychology: General, 106, 376–403.

Postman, L., & Stark, K. (1969). Role of response availability in transfer and interference.

Journal of Experimental Psychology, 79, 168–177.

Postman, L., & Underwood, B. J. (1973). Critical issues in interference theory. Memory and Cognition, 1(1), 19–40.

Pribram, K. H. (1994). Brain and the structure of narrative. In D. S. Levine, & M. Aparicio IV (Eds.), Neural networks for knowledge representation and inference (pp. 375–417). Hillsdale, NJ: Lawrence Erlbaum Associates, Inc. Putnam, H. (1975a). The meaning of meaning. In K. Gunderson (Ed.), Language, mind, and knowledge (pp. 131–193). Minneapolis: University of Minnesota Press.

Putnam, H. (1975b). Minds and machines. In H. Putnam (Ed.), Mind, language, and reality (pp.

362–385). Cambridge, UK: Cambridge University Press.

Pylyshyn, Z. W. (1973). What the mind’s eye tells the mind’s brain: A critique of mental imagery. Psychological Bulletin, 80, 1–25.

Pylyshyn, Z. W. (1981). The imagery debate: Analogue media versus tacit knowledge.

Psychological Review, 88, 16–45.

Raaijmakers, J. G., & Shiffrin, R. M. (1981). Search of associative memory. Psychological Review, 88, 93–134.

Ratcliff, R., & McKoon, G. (1994). Retrieving information from memory: Spreading activation theories versus compound-cue theories. Psychological Review, 101, 177–184.

Human Memory: A Constructivist View

247

Rauch, S. L., Savage, C. R., Alpert, N. M., Fischman, A. J., & Jenike, M. A. (1997). The functional neuroanatomy of anxiety: A study of three disorders using positron emission tomography and symptom provocation. Biological Psychiatry, 42, 446–452.

Reber, T. P., Leuchinger, R., Boesiger, P., & Henke, K. (2012). Unconscious relational inference recruits the hippocampus. Journal of Neuroscience, 32, 6138–6148.

Reichelt, A. C., & Lee, J. L. C. (2013). Over-expectation generated in a complex appetitive goal-tracking task is capable of inducing memory reconsolidation. Psychopharmacology, 226, 649–658.

Reisberg, D., & Heuer, F. (2004). Memory for emotional events. In D. Reisberg, & P. Hertel (Eds.), Memory and emotion (pp. 3–41). New York: Oxford University Press.

Reisberg, D., Heuer, F., McLean, J., & O’Shaughnessy, M. (1988). The quantity, not the quality, of affect predicts memory vividness. Bulletin of the Psychonomic Society, 26, 100–103.

Reyna, V. F. (1995). Interference effects in memory and reasoning: A fuzzy-trace theory analysis. In F. N. Dempster, & C. J. Brainerd (Eds.), Interference and inhibition in cognition (pp. 29–61). New York: Academic Press.

Reyna, V. F., & Brainerd, C. J. (1998). Fuzzy-trace theory and false memory: New frontiers.

Journal of Experimental Child Psychology, 71, 194–209.

Reyna, V. F. & Brainerd, C. J. (2004, July-August). What theories of memory tell us about the brain: Implications for aging, development and impairment. Invited plenary address presented at the 12th Annual Convention of the American Psychological Association, Honolulu, HI. Reyna, V. F., & Mills, B. A. (2007). Interference processes in fuzzy-trace theory: Aging, Alzheimer disease, and development. In D. S. Gorfein, & C. M. MacLeod (Eds.), Inhibition in cognition (pp. 185–210). Washington, DC: American Psychological Association.

Richardson, R., Riccio, D., & Axiotis, R. (1986). Alleviation of infantile amnesia in rats by internal and external contextual cues. Developmental Psychobiology, 19, 453–462.

Rinck, M., Williams, P., Bower, G. H., & Becker, E. S. (1996). Spatial situation models and narrative understanding: Some generalizations and extensions. Discourse Processes, 21, 23–55.

Roediger, H. L., & Payne, D. G. (1982). Hypermnesia: The role of repeated testing. Journal of Experimental Psychology: Learning, Memory and Cognition, 8, 66–72.

Roediger, H. L., & Schmidt, S. R. (1980). Output interference in the recall of categorized and paired-associate lists. Journal of Experimental Psychology: Human Learning and Memory, 6, 91–105.

Roediger, H. L., & Thorpe, L. A. (1978). The role of recall time in producing hypermnesia.

Memory & Cognition, 6, 296–305.

Roozendaal, B. (2000). Glucocorticoids and the regulation of memory consolidation.

Psychoneuroendocrinology, 25, 213–238.

Rosch, E. H. (1973). On the internal structure of perceptual and semantic categories. In T. E. Moore (Ed.), Cognitive development and the acquisition of language. Oxford, UK: Academic Press.

Rosch, E. (1975). Cognitive representations and semantic categories. Journal of Experimental Psychology, General, 104, 192–233.

Rosch, E., & Lloyd, B. B. (1978). Cognition and categorization. Hillsdale, NJ: Lawrence Erlbaum.

Rosch, E., & Mervis, C. B. (1975). Family resemblances: Studies in the internal structure of categories. Cognitive Psychology, 7, 573–605.

Rosch, E., Mervis, C. B., Gray,W. D., Johnson, D. M., & Boyes-Braem, P. (1976). Basic objects in natural categories. Cognitive Psychology, 8, 382–439.

Rovee-Collier, C. (1999). The development of infant memory. Current Directions in Psychological Science, 8, 80–85.

248

References

Rovee-Collier, C., Borza, M. A., Adler, S. A., & Boller, K. (1993). Infants’ eyewitness testimony: Effects of postevent information on a prior memory representation. Memory & Cognition, 21, 267–279.

Rovee-Collier, C., Hartshorn, K., & DiRubbo, M. (1999). Long-term maintenance of infant memory. Developmental Psychobiology, 35, 91–102.

Rubin, D. C. (1986). Autobiographical memory. Cambridge, UK: Cambridge University Press.

Rubin, D. C., Feldman, M. E., & Beckham, J. C. (2004). Reliving, emotions, and fragmentation in the autobiographical memories of veterans diagnosed with PTSD. Applied Cognitive Psychology, 18, 17–35.

Rubin, D. C., & Kozin, M. (1984). Vivid memories. Cognition, 16, 81–95.

Rumelhart, D. E., & McClelland, J. L. (1986). Parallel distributed processing: Explorations in the microstructure of cognition (Vol. 2). Cambridge, MA: MIT Press.

Runquist, W. N. (1969). Positive and negative transfer resulting from formal similarity of stimuli. Journal of Experimental Psychology, 82, 129–135.

Ryan, J. (1969a). Grouping and short-term memory: Different means and patterns of grouping. Quarterly Journal of Experimental Psychology, 21, 137–147.

Ryan, J. (1969b). Temporal grouping, rehearsal and short-term memory. Quarterly Journal of Experimental Psychology, 21, 148–155.

Rybash, J. M., & Hrubi-Bopp, K. L. (2000). Source monitoring and false recollection: A life span developmental perspective. Experimental Aging Research, 26, 75–87.

Sargent, W., & Slater, E. (1941). Amnesic syndromes in war. Proceedings of the Royal Society of Medicine, 34, 757–764.

Saufley, W. H., Otaka, S. R., & Bavaresco, J. L. (1985). Context effects: Classroom tests and context independence. Memory & Cognition, 13, 522–528.

Schacter, D. L., & Tulving, E. (1994). What are the memory systems of 1994? In D. L. Schacter, & E. Tulving (Eds.), Memory systems 1994 (pp. 1–38). Cambridge, MA: The MIT Press.

Schank, R. C. (1982). Dynamic memory: A theory of reminding and learning in computers and people. New York: Cambridge University Press.

Schank, R. C. (1999). Dynamic memory revisited. New York: Cambridge University Press.

Schank, R. C., & Abelson, R. P. (1977). Scripts, plans, goals and understanding: An inquiry into human knowledge structures. Hillsdale, NJ: Lawrence Erlbaum.

Schmolck, H., Buffalo, E. A., & Squire, L. R. (2000). Memory distortions develop over time: Recollections of the O. J. Simpson trial verdict after 15 and 32 months. Psychological Science, 11, 39–45.

Schooler, J. W., Gerhard, D., & Loftus, E. F. (1986). Qualities of the unreal. Journal of Experimental Psychology: Learning, Memory, and Cognition, 12, 171–181.

Schooler, J. W., & Hermann, D. J. (1992). There is more to episodic memory than just episodes. In M. A. Conway, D. C. Rubin, H. Spinnler, & W. A. Wagenaar (Eds.), Theoretical perspectives on autobiographical memory (pp. 241–262). Dordrecht:The Netherlands: Klewer Academic.

Schreiber, T. A., & Sergent, S. D. (1998). The role of commitment in producing misinformation effects in eyewitness memory. Psychonomic Bulletin and Review, 5, 443–448.

Schwartz, B. L., Meissner, C. A., Hoffman, M., Evans, S., & Frazier, L. D. (2004). Event memory and misinformation effects in a gorilla (Gorilla, gorilla, gorilla). Animal Cognition, 7, 93–100.

Schwartz, G., Howard, M.W., Jing, B., & Kahana, M. J. (2005). Shadows of the past:Temporal retrieval effects in recognition memory. Psychological Science, 16, 898–904.

Scoboria, A., Mazzoni, G., Kirsch, I., & Milling, L. S. (2002). Immediate and persisting effects of misleading questions and hypnosis on memory reports. Journal of Experimental Psychology: Applied, 8, 26–32.

Human Memory: A Constructivist View

249

Scoville, W. B., & Milner, B. (1957). Loss of recent memory after bilateral hippocampal lesions. Journal of Neurology, Neurosurgery and Psychiatry, 20, 11–21.

Serra, M., & Nairne, J. S. (2000). Part-set cuing of order information: Implications for associative theories of serial order memory. Memory & Cognition, 28, 847–855.

Sheehan, P. W., Statham, D., Jamieson, G. A., & Ferguson, S. R. (1991). Ambiguity in suggestion and the occurrence of pseudomemory in the hypnotic setting. Australian Journal of Clinical and Experimental Hypnosis, 19, 1–18.

Sheldon, K. M., & Elliot, A. J. (1999). Goal striving, need satisfaction, and longitudinal wellbeing:The self-concordance model. Journal of Personality and Social Psychology, 76, 482–497.

Shepard, R. N. (1990). Mind sights: Original visual illusions, ambiguities, and other anomalies, with a commentary on the play of mind in perception and art. New York: W. H. Freeman/Times Books/Henry Holt & Co. Sigurdsson, T., Doyère, V., Cain, C. K., & LeDoux, J. E. (2007). Long-term potentiation in the amygdala: A cellular mechanism of fear learning and memory. Neuropharmacology, 52, 215–227.

Singer, J. A. (1997). How recovered memory debates reduce the richness of human identity.

Psychological Inquiry, 8, 325–329.

Singer, J. A., & Salovey, P. (1993). The remembered self: Emotion and memory in personality. New York: Free Press.

Singer, J. A., & Salovey, P. (1999). Motivated memory: Self-defining memories, goals, and affect regulation. In L. L. Martin, & A. Tesser (Eds.), Striving and feeling: Interactions among goals, affect, and self-regulation (pp. 229–250). Hillsdale, NJ: Lawrence Erlbaum Associates, Inc. Skinner, B. F. (1974). About behaviorism. Oxford, UK: Alfred A. Knopf.

Slamecka, N. J. (1968). An examination of trace storage in free recall. Journal of Experimental Psychology, 76, 504–513.

Slamecka, N. J. (1969). Testing for associative storage in multitrial free recall. Journal of Experimental Psychology, 81, 557–560.

Smith, A. D. (1971). Output interference and organized recall from long-term memory.

Journal of Verbal Learning and Verbal Behavior, 10, 400–408.

Smith, E. E., & Medin, D. L. (1981). Categories and concepts. Cambridge, MA: Harvard University Press.

Smith, E. E., Shoben, E. J., & Rips, L. J. (1974). Structure and process in semantic memory: A featural model for semantic decisions. Psychological Review, 81, 214–241.

Smith, S. M. (1979). Remembering in and out of context. Journal of Experimental Psychology: Human Learning and Memory, 5, 460–471.

Smith, S. M., Glenberg, A., & Bjork, R. A. (1978). Environmental context and human memory. Memory & Cognition, 6, 342–353.

Smith, S. M., Vela, E., & Williamson, J. E. (1988). Shallow input processing does not induce environmental context-dependent recognition. Bulletin of the Psychonomic Society, 26, 537–540.

Spelke, E. S. (1985). Preferential-looking methods as tools for the study of cognition in infancy. In G. Gottleib, & N. A. Krasnegor (Eds.), Measurement of audition and vision in the first year of postnatal life: A methodological overview (pp. 323–363). Westport, CT: Ablex Publishing.

Squire, L. R. (1981). Two forms of human amnesia: An analysis of forgetting. Journal of Neuroscience, 1, 635–640.

Squire, L. R. (1992). Memory and the hippocampus: A synthesis from findings with rats, monkeys, and humans. Psychological Review, 99, 195–231.

Squire, L. R., & Kandel, E. R. (1999). Memory: From mind and molecules. New York: Scientific American Library/Scientific American Books.

250

References

Stalnaker, J. M., & Riddle, E. E. (1932). The effect of hypnosis on long-delayed recall. Journal of General Psychology, 6, 429–440.

Stanny, C. J., & Johnson, T. C. (2000). Effects of stress induced by a simulated shooting on recall by police and citizen witnesses. American Journal of Psychology, 113, 359–386.

Steblay, N. M. (1992). A meta-analytic review of the weapon focus effect. Law and Human Behavior, 16, 413–424.

Stern, W. (1904/1982). Realistic experiments. In U. Neisser (Ed.), Memory observed (pp.

199–213). San Francisco: W. H. Freeman.

Stuss, D. T. (1992). Biological and psychological development of executive functions. Brain and Cognition, 20, 8–23.

Sulin, R. A., & Dooling, D. J. (1974). Intrusion of a thematic idea in retention of prose.

Journal of Experimental Psychology, 103, 255–262.

Talland, G. A., Mendelson, J. H., Koz, G., & Aaron, R. (1965). Experimental studies of the effects of tricyanoaminopropene on the memory and learning capacities of geriatric patients. Journal of Psychiatric Research, 3, 171–179.

Talmy, L. (1985). Force dynamics in language and thought. In W. H. Eilfort, P. D. Kroeber, & K. L. Peterson (Eds.), Papers from the parasession on causatives and agentivity at the twenty first regional meeting (pp. 293–337). Chicago: Chicago Linguistic Society.

Thompson, C. P., & Cowan, T. (1986). Flashbulb memories: A nicer interpretation of a Neisser recollection. Cognition, 22, 199–200.

Thorndike, E. L., & Lorge, I. (1944). The teacher’s word book of 30,000 words. Oxford, UK: Bureau of Publications, Teachers Co. Thorndyke, P. W. (1977). Cognitive structures in comprehension and memory for narrative discourse. Cognitive Psychology, 99, 77–110.

Toglia, M. P., Hembrooke, H., Ceci, S. J., & Ross, D. F. (1994). Children’s resistance to misleading postevent information: When does it occur? Current Psychology: A Journal for Diverse Perspectives on Diverse Psychological Issues, 13, 21–26.

Torregrossa, M. M., & Taylor, J. R. (2013). Learning to forget: Manipulating extinction and reconsolidation processes to treat addiction. Psychopharmacology, 226, 659–672.

Tousignant, J. P., Hall, D., & Loftus, E. F. (1986). Discrepancy detection and vulnerability to misleading postevent information. Memory & Cognition, 14, 329–338.

Tranel, D., & Hyman, B. T. (1990). Neuropsychological correlates of bilateral amygdala damage. Archives of Neurology, 47, 349–355.

Treadway, M., McCloskey, M., Gordon, B., & Cohen, N. J. (1992). Landmark life events and the organization of memory: Evidence from functional retrograde amnesia. In S.-Å. Christiansen (Ed.), The handbook of emotion and memory: Research and theory (pp.

389–410). Hillsdale, NJ: Lawrence Erlbaum Associates, Inc. Treffert, D. A. (1988). The idiot savant: A review of the syndrome. American Journal of Psychiatry, 145, 563–572.

Treisman, A. M. (1970). Perception and recall of simultaneous speech stimuli. Acta Psychologica, 33, 132–148.

Treisman, M., Cook, N., Naish, P. L. N., & MacCrone, J. K. (1994). The internal clock: Electroencephalographic evidence for oscillatory processes underlying time perception. Quarterly Journal of Experimental Psychology A: Human Experimental Psychology, 47, 241–289.

Tulving, E. (1966). Subjective organization and effects of repetition in multi-trial free-recall learning. Journal of Verbal Learning and Verbal Behavior, 5, 193–197.

Tulving, E. (1974). Cue-dependent forgetting. American Scientist, 62, 74–82.

Tulving, E. (1976). Ecphoric processes in recall and recognition. In J. Brown (Ed.), Recall and recognition. Oxford, UK: John Wiley & Sons.

Tulving, E. (1982). Synergistic ecphory in recall and recognition. Canadian Journal of Psychology, 36, 130–147.

Human Memory: A Constructivist View

251

Tulving, E. (1983). Elements of episodic memory. New York: Oxford University Press.

Tulving, E. (1985). Memory and consciousness. Canadian Psychologist, 26, 1–12.

Tulving, E. (2002). Episodic memory: From mind to brain. Annual Review of Psychology, 53, 1–25.

Tulving, E., & Osler, S. (1968). Effectiveness of retrieval cues in memory for words. Journal of Experimental Psychology, 77, 593–601.

Tulving, E., & Pearlstone, Z. (1966). Availability versus accessibility of information in memory for words. Journal of Verbal Learning & Verbal Behavior, 5, 381–391.

Tulving, E., & Psotka, J. (1971). Reproductive inhibition in free recall: Inaccessibility of information available in the memory store. Journal of Experimental Psychology, 87, 1–8.

Tulving, E., & Thomson, D. M. (1973). Encoding specificity and retrieval processes in episodic memory. Psychological Review, 80, 352–373.

Tversky, B., & Tuchin, M. (1989). A reconciliation of the evidence on eyewitness testimony: Comments on McCloskey and Zaragoza. Journal of Experimental Psychology: General, 118, 86–91.

Underwood, B. J. (1945). The effect of successive interpolations on proactive and retroactive interference. Psychological Monographs, 59, 1–33.

Underwood, B. J. (1948).

“Spontaneous recovery” of verbal associations. Journal of Experimental Psychology, 38, 429–439.

Underwood, B. (1949). Proactive inhibition as a function of time and degree of prior learning. Journal of Experimental Psychology, 39, 24–34.

Underwood, B. J. (1969). Attributes of memory. Psychological Review, 76, 559–573.

Underwood, B. J. (1983a). Attributes of memory. Glenview, IL: Scott Foresman.

Underwood, B. J. (1983b). “Conceptual” similarity and cumulative proactive inhibition.

Journal of Experimental Psychology: Learning, Memory, and Cognition, 9, 456–461. van der Kolk, B. A. (1996). Trauma and memory. In B. A. van der Kolk, A. C. McFarlane, & L. Weisaeth (Eds.), Traumatic stress: The effects of overwhelming experience on mind, body, and society (pp. 279–302). New York: Guilford Press.

Vousden, J. I., Brown, G. D. A., & Harley, T. A. (1997). Serial control of phonology in speech production: A hierarchical model. Cognitive Psychology, 41, 101–175.

Wagenaar, W. A., & Groeneweg, J. (1990). The memory of concentration camp survivors.

Applied Cognitive Psychology, 4, 77–87.

Wagoner, B. (2008). Narrative form and content in remembering. Integrative Psychological & Behavioral Science, 42, 315–323.

Waldfogel, S. (1948). The frequency and affective character of childhood memories.

Psychological Monographs: General and Applied, 62, i-39.

Warrington, E. K., & Shallice, T. (1984). Category specific semantic impairments. Brain, 107, 829–854.

Watkins, M. J., & Watkins, O. C. (1976). Cue-overload theory and the method of interpolated attributes. Bulletin of the Psychonomic Society, 7, 289–291.

Watkins, O. C., & Watkins, M. J. (1975). Buildup of proactive inhibition as a cue-overload effect. Journal of Experimental Psychology: Human Learning and Memory, 104, 442–452.

Watson, B. (1938). The similarity factor in transfer and inhibition. Journal of Educational Psychology, 29, 145–157.

Webb, L. W. (1917). Transfer of training and retroaction: A comparative study. Psychological Monographs, 24, i-90.

Weiskranz, L. (1956). Behavioral changes associated with ablation of the amygdaloid complex in monkeys. Journal of Comparative and Physiological Psychology, 49, 381–391.

Wessel, I., & Merckelbach, H. (1997). The impact of anxiety on memory for details in spider phobics. Applied Cognitive Psychology, 11, 223–231.

Wessel, I., & Merckelbach, H. (1998). Memory for threat-relevant and threat-irrelevant cues in spider phobics. Cognition and Emotion, 12, 93–104.

252

References

Wetzler, S. (1985). Mood state-dependent retrieval: A failure to replicate. Psychological Reports, 56, 759–765.

Wheeler, M. A., & Roediger, H. L. III, (1992). Disparate results of repeated testing: Reconciling Ballard’s (1913) and Bartlett’s (1932) results. Psychological Science, 3, 240–245.

White, T. H. (1958). The once and future king. London: Collins.

Whitehouse, W. G., Dinges, D. F., Orne, E. C., & Orne, M. T. (1988). Hypnotic hypermnesia: Enhanced memory accessibility or report bias? Journal of Abnormal Psychology, 97, 289–295.

Wickelgren, W. A. (1965a). Acoustic similarity and intrusion errors in short-term memory.

Journal of Experimental Psychology, 70, 102–108.

Wickelgren, W. A. (1965b). Acoustic similarity and retroactive Interference in short-term memory. Journal of Verbal Learning and Verbal Behavior, 4, 53–61.

Wickelgren, W. A. (1966). Phonemic similarity and interference in short-term memory for single letters. Journal of Experimental Psychology, 71, 396–404.

Wickens, D. D., Born, D. G., & Allen, C. K. (1963). Proactive inhibition and item similarity in short-term memory. Journal of Verbal Learning and Verbal Behavior, 2, 440–445.

Wilkinson, C. B. (1983). Aftermath of a disaster: The collapse of the Hyatt Regency Hotel skywalks. American Journal of Psychiatry, 140, 1134–1139.

Wilson, B. A., Baddeley, A. D., & Kappur, N. (1995). Dense amnesia in a professional musician following herpes simplex virus encephalitis. Journal of Clinical and Experimental Neuropsychology, 17, 668–681.

Winocur, G., & Kinsbourne, M. (1978). Contextual cueing as an aid to Korsakoff amnesics.

Neuropsychologia, 16, 671–682.

Wittgenstein, L. (1953). Philosophical investigations. Oxford, UK: Macmillan.

Wixted, J. T. (2004). The psychology and neuroscience of forgetting. Annual Review of Psychology, 55, 235–269.

Wixted, J. T. (2010). The role of retroactive interference and consolidation in everyday forgetting. In S. Della Sala (Ed.), Forgetting (pp. 285–312). New York: Psychology Press.

Wright, D. B. (1993). Recall of the Hillsborough disaster over time: Systematic biases of “flashbulb” memories. Applied Cognitive Psychology, 7, 129–138.

Wynn,V. E., & Logie, R. H. (1998). The veracity of long-term memories: Did Bartlett get it right? Applied Cognitive Psychology, 12, 1–20.

Yaroush, R., Sullivan, M. J., & Ekstrand, B. R. (1971). Effect of sleep on memory: II. Differential effect of the first and second half of the night. Journal of Experimental Psychology, 88, 361–366.

Yerkes, R. M., & Dodson, J. D. (1908). The relation of strength of stimulus to rapidity of habit formation. Journal of Comparative Neurology and Psychology, 18, 459–482.

Yuille, J. C., & Tollestrup, P. A. (1992). A model of the diverse effects of emotion on eyewitness memory. In S.-Å. Christiansen (Ed.), The handbook of emotion and memory: Research and theory (pp. 201–215). Hillsdale, NJ: Lawrence Erlbaum Associates, Inc. Zangwill, O. L. (1972). Remembering revisited. Quarterly Journal of Experimental Psychology, 24, 123–138.

Zaragoza, M. S., & McCloskey, M. (1989). Misleading postevent information and the memory impairment hypothesis: Comment on Belli and reply to Tversky and Tuchin.

Journal of Experimental Psychology: General, 118, 92–99.

Zaragoza, M. S., McCloskey, M., & Jamis, M. (1987). Misleading postevent information and recall of the original event: Further evidence against the memory impairment hypothesis. Journal of Experimental Psychology: Learning, Memory, and Cognition, 13, 36–44.

Zaragoza, M. S., & Lane, S. M. (1994). Source misattributions and the suggestibility of eyewitness memory. Journal of Experimental Psychology: Learning, Memory, and Cognition, 20, 934–945.

Human Memory: A Constructivist View

253

Zola-Morgan, S., Squire, L. R., Alvarez-Royo, P., & Clower, R. P. (1991). Independence of memory functions and emotional behavior: Separate contributions of the hippocampal formation and the amygdala. Hippocampus, 1, 207–220.

Zwaan, R. A., Radvansky, G. A., & Witten, S. (2002). Situation models and themes. In M. Louwerse, & W. van Peer (Eds.), Thematics: Interdisciplinary studies (pp. 35–53).

Amsterdam: John Benjamins Publishing Company.

INDEX A

B

ACT. See Adaptive Control of Thought ACTE. See Adaptive Control of Thought version E Active information processing system, 164 memory as, 164–165 Activity models, 208–209 Adaptive Control of Thought (ACT), 33 Adaptive Control of Thought version E (ACTE), 132–133 Agency, 214 Altered memories candidate selection for retrieval, variables influencing, 150–157 episodic memory alterations in, 137–142 content, models of, 142–150 Amnesic syndrome, 119 Amygdala in emotional memories, 190–193 and herpes simplex encephalitis, 191–192 and urbach-Wiethe disease, 191–192 Analog representation, 174 Anterograde amnesia, 119 Aristotelian neoclassic model, 121 Aristotle, 2, 4 Associative hypothesis, 52 Associative links, traditional Ebbinghausian view of, 41–42 Autobiographical memory, 28, 90–102 dissociative elements in recall, 97–100 episode evaluation, 96–97 episodic recall vs. word-list recall, 101 headers and subset links, 94 input-bound and output-bound memories, 100–101 Linton’s model, 91–94 mushing, 101–102 retrieval of, 192 retrieval of episode, 94–96

Background knowledge (schemas), 71 Bartlett, Frederick emphasis on associations, 67 fundamental claim, 111 methodological approach vs. modern practices, 82–83 nonreplication of findings of, 80 War of Ghosts study, 78–80 Barrow memory, 37–40 Biochemical reconsolidation process, 195–196 Blocking hypothesis, 152 Borderline memory, 86 Burgess model, 50

C Case grammar, 172–173 Causality, 210–211, 214, 216 Causal links, 222 Chaining theory, 35–36 Classic-Aristotelian theorists, 68 Classic interference effect, 52–53 Coding for functional information, 68–70 similarity, 52–54 strength, 109–110 Cognitive structures. See Processing structures Coherence, 77–78 Complex chaining models, 35 Compound cue models, 10–11 Concepts, core properties of, 120–122 Conceptual hierarchies, misinformation effect using, 206–207 Conceptual schemas, 203, 218 Conditioned response, 226 Confabulation, 165 Conrad’s boxes model, 47 Conscious activity, 115–116 Conscious processes, 122–129 Conscious representation, 123 255

256

Index

Consolidation-based interference effects in misleading scene, 155–157 Constructivism empiricism to. See Empiricism, to constructivism episodic recall and memory reconstruction. See Episodic recall, and memory reconstruction long-term memory codes, 67–70 nature of higher-order schemas. See Nature of higher-order schemas origins of, 65–66 reconstruction processes, 66 Constructivist model, 77, 159 Constructivist theory, 25 Constructivist view, 138–139 Containment, 214–215 Context states, 58–59 Contextual element contiguity links, 24 importance of, 22–23 physiological matching effects, 24 Contextual influences, 207–208 Contiguity, 4 Contiguity links, 221 role of, 21 for word retrieval, 22 Control nodes, 51 models based on, 48–50, 53–54 Control processes, 115–116 Cue-dependent theory, 8–9 of memory, 9 Cue-overload effect, 225 Cues, 6–9, 13, 87, 105 Cyclical retrieval models, 9–12, 16

D Declarative memory, 190 Demand characteristics, 141 Descriptive headers, 62 de Valera memory, 200 Discriminability, 107–109 Dissociative elements in recall, 97–100 Dissociative model, 159–160 Distant personal memory, critical analysis of, 86–90 Divorce hypothesis, 202–203 Dunedin memory, 18

Dynamic changing-states models, 59

E “Easter parade” recollection, 170 Ebbinghausian model, 34, 66 and associative links, 41-42 Emotion and early memories, 183–185 and goals, 182–183 and memory in everyday life, 181–190 physiological basis of memories characterized by, 190–193 on recall, effect of, 177–181 thematic source of, 180 Emotional memories, 187, 192–193 role of amygdala in, 190–193 thematically based, 180–181 Emotion-simulating drugs, 182 Empiricism, 21, 37 to constructivism, 66–67 Bartlett’s emphasis on associations, 67 hard-line empiricism, 66–67 questioning, 35–37 Empiricist memory system, 75–76 Empiricist view, 138 Encoding-based interference, 151 Environmental stimuli and memory content, 21, 25, 29 Episodic memory, 61 alterations in, 137–142 concept schemas in recall and, 201–203 content, models of, 142–150 evaluation, 96–97 Genevan view of, 119–122 retrieval of, 94–96 Episodic recall and memory reconstruction, 70–76 empiricist memory system, 75–76 Piaget’s view, 73–75 reconstruction through perceptual inference, 72–73 value of schemas, 71–72 vs. word-list recall, 101 Estes’s perturbation model, 47–48 Evaluative processes in retrieval, 162–164

Index

Eyewitness memory, attentional factors in, 180

F Figural elements, 116–119 Flashbulb memories, 185–188 “Fragment memories”, 183–184 FRAN. See Free Recall from an Associative Network Free Recall from an Associative Network (FRAN), 24, 26–27, 33, 132–133 Frontal lobe damage, 166 Functional information, coding for, 68–70

G Gareth-Family-Dog representation, 145–146 General reality testing, 162–163 Genevan model, 197–198 Genevan view conscious processes and memory content, 122–129 developmental processes in schema representation, 124–125 Inhelder’s research on development of seriation, 125–126 schemas, 124 seriation ability, stages of development in, 126–129 signs, 122–123 symbolic images, 123–124 of episodic and semantic memory, 119–122 core properties of concepts, 120–122 of human memory, 111–116 higher-order schemas, role of, 113–114 knowledge structures, 114–116 non-divorce hypothesis, 116 semantic vs. perceptual coding, 112–113 Great Sky River (Benford), 75

H Hard-line constructivism, 72, 219 claim of, 74 Hard-line constructivist theory, 218

257

Hard-line empiricism, 34–35, 66–67 Headers, 94 formation of, 150–151 and memory intrusions, 32–33 Hierarchical coding of order, 57–58 Higher-order schemas, role of, 113–114 High Street memory, 39 Hound of the Baskervilles, The, 8 Hypermnesia, 81–82

I Identity-based models, 204–205 Identity links, 221 Image schemas, 215, 217 role of, 212–218 Independence/noninteractionist model, 143 Individuating effect, 203 Infantile amnesia, 185 Infants, schema development in, 210–212 Inference, 85–86 vs. memory replacement, 161–162 Inferential reconstruction, constraints on function of, 170 Inhelder’s research on development, of seriation, 125–126 Input-bound memories, 100–101 Interactive hypothesis, 143–145 Interference effects, 15–16, 54, 151–154 Interference theory, 226

K Kantian views, 65 Knowledge structures, 114–116

L Lee model, 48 Links, 215–216 contiguity, identity, and similarity, 4–5 and memory strength, 5–6 operation of, 1–6 and retrieval goals, 3–4 Linton’s model of autobiographical memory, 91–94 Lockean-Humean position, 25 Lockean view, 66

258

Index

Long-term memory (LTM), 2–3, 6–8, 11–12, 21, 41–42, 85, 137, 161–162, 165, 182–183, 199 codes, 67–70 content through headers, accessing, 28–29 context and coding in, 129–135 cuing, Genevan explanation of, 133–134 divorce hypothesis, 132–133 retrieval cues, 131–132 schema integration and capacity of working memory, 134–135 extended activation within, 165–166 knowledge, 65–66 model of access into, 38 obscure content in, 166–167 organization of content in, 104–106 role of schemas in, 197–201 spreading activation in, 14 LTM. See Long-term memory

M Memory. See also Autobiographical memory accuracy, 80–81 change factors influencing, 139–140 replacement hypothesis for, 140–141 concepts influencing percepts in, 118–119 dissociable nature of, 159–162 empiricist vs. constructivist views of, 34–40 fate of nonselected items in, 147–149 links in, 221 perceptual and motor schemas in, 209–218 recency of information in, 150 reconstruction, 70–76 retrieval, 106–110 for stressful events, 178–180 for syntactic relations, alterations in, 160–161 test, form of, 154–155 visual codes in, 116–119 Memory content, 122–129

retrievability of, 162–167 Memory errors, 43 due to reconstruction, 70 Memory-forcing effect, 167–169 Memory imagery, influence of schemas on, 118 Memory organization packages (MOPs), 182–183 Memory retrieval models of, 9–19 and specification cues, 30–34 Memory search process, modeling, 26–28 Misinformation effect, 137–142 “Misled” condition, 137–138 Modified modified free recall test (MMFR), 227 Modified test (MT), 140–141, 155 paradigm, 154 Mood tone, 91–92 MOPs. See Memory organization packages Moroccan trip, personal memory of, 102–106 Motor schemas in memory, perceptual schemas and, 209–218 MT. See Modified test Mushing, 101–102

N Nature of higher-order schemas, 76–83 Bartlett’s methodological approach vs. modern practices, 82–83 Bartlett’s War of Ghosts study, 78–80 nonreplication of Bartlett’s findings, 80 output interference, 81–82 reminiscence, 81 repeated testing and memory accuracy, 80–81 schema representation and consciousness, 76–77 schemas and coherence, 77–78 Negative transfer, 224 Neoclassic Aristotelian tradition, 120 Neoclassic model, 207–208 Neurological damage and retrieval, 165 Noetic experience, 102 Nondeclarative memory, 190 Non-divorce hypothesis, 116 Noninteractive hypothesis, 143

Index

O Once and Future King, The (White), 202 Order errors, 54–55 in human recall, 52 Order links, 221–222 Oscillator models, 50, 52, 54–57 of order recall, 53 Output-bound memories, 100–101 Output interference, 81–82

P Paired-associate paradigm, 226–227 Part/whole links, 222 Pavlovian process, 226 Perceptual analysis, 215 Perceptual coding vs. semantic codes, 68, 112–113 Perceptual schemas, 116–119, 123 and motor schemas in memory, 209–218 Personal memory autobiographical memory, nature of. See Autobiographical memory critical analysis of distant, 86–90 methods used in, 86–87 factors influencing memory retrieval, 106–110 coding strength, 109–110 discriminability, 107–109 positional coding, 106 retrieval cues, 106–107 of Moroccan trip, 102–106 Perturbation model, 47–48 Piagetian model, 73–75, 198 vs. traditional mainstream approaches to human recall, 112–113 Piaget’s model, 210–211 context and coding in long-term memory. See Long-term memory, context and coding in Genevan view conscious processes and memory content. See Genevan view, conscious processes and memory content of episodic and semantic memory, 119–122

259

of human memory. See Genevan view, of human memory visual codes in memory, 116–119 Carmichael, Hogan, and Walter’s 1932 Study, 118–119 Plato, 1–2 Positional coding, 106 Positional processing structures, temporal vs., 60–62 Position coding functions in serial recall, 50–59 associative hypothesis, 52 Brown, Preece, and Hulme’s oscillator model, 54–57 coding similarity, 52–54 context states, 58–59 hierarchical coding of order, 57–58 position coding errors, 52 Post-traumatic stress disorder (PTSD), 188 Primacy effects, 101–102 Proactive interference, 224 Processing structures, 60–61 descriptive headers and position coding, 62 and memory errors, 43 rationale for, 41–43 contrasting models, 42–43 for serial recall. See Serial recall subset links, 62–63 temporal vs. positional, 60–62 Propositional coding, 170–175 PTSD. See Post-traumatic stress disorder

R Rationalist theory, 25 Reality-checking functions, 165 Recall, dissociative elements in, 97–100 Recency effects, 101 Reconstruction process, 65–66 memory errors due to, 70 through perceptual inference, 72–73 Rehearsal, Heuer and Reisberg’s study on emotion and, 182 Reminiscence, 81 Remote memories, 86–87 Repeated testing, 80–81 Replacement hypothesis for memory change, 140–141

260

Index

Replications of Tulving’s data, 132–133 Retrieval-based interference, 151 Retrieval cues, 106–107 Retrieval models, applications of, 16–17 Retroactive interference, 225, 227

S Savant syndrome, 75 Schank’s model for retrieval, 149–150 Schemas, 109, 124 background knowledge, 71 and coherence, 77–78 Genevan View of, 124 integration of working memory, 134–135 in long-term memory, role of, 197–201 memory imagery, influence of, 118 representation and consciousness, 76–77 representation, developmental processes in, 124–125 theoretical models of, 203–209 value of, 71–72 Semantic codes, perceptual vs., 68 Semantic memory, Genevan view of, 119–122 Semantic vs. perceptual coding, 112–113 Serial recall, 43–47 factors affecting, 54 other approaches to, 59 position coding functions in. See Position coding functions in serial recall temporal models, 44–47 theories of, 47–50 Conrad’s boxes model, 47 control nodes, models based on, 48–50 Estes’s perturbation model, 47–48 oscillator models, 50 Seriation ability, stages of development in, 126–129 Piaget and Inhelder’s research on development of, 125–126 Short-term memory (STM), 35, 38 Signs, 122–123 Similarity-based interference effects, 201 Similarity-based models, 204–205 Similarity links, 221

Source misattribution, 85, 98 Specification cues, 30–32 Spontaneous recovery, 226–227 Spreading activation model, 9, 12–15 Anderson and Bower’s FRAN model of, 24–26 Anderson’s ACT model, 33–34 barrow memory, 37–40 contiguity links role of, 21 for word retrieval, 22 empiricism, 37 hard-line empiricism, 34–35 headers and memory intrusions, 32–33 long-term memory content through headers, accessing, 28–29 LTM, 21 memory and context, 22–30 empiricist vs. constructivist views of, 34–40 retrieval and specification cues, 30–34 search process, modeling, 26–28 questioning empiricism, 35–37 specification cues, 31–32 traditional empiricist model, 21 Spreading activation tradition, 27 Standard hypermnesic effect, 125 STM. See Short-term memory “Strength” theories, 26 Subset Association hypothesis, 147–149 Subset links, 62–63, 94 Subset-relation hypothesis, 145 Subset/superset links, 222 Superordinate concept, 206–207 Symbolic coding, 218 Symbolic images, 123–124 Symbols, 173 in computer and cognitive literatures, 124 Syntactic relations, alterations in memory for, 160–161

T Temporal links, 2–3, 222 Temporal models, 44–47 Temporal vs. positional processing structures, 60–62

Index

Thematically based emotional memories, 180–181 Time-of-occurrence (TOC), 142 codes, 146 information, 142 Time-slice errors, 85, 87, 96, 99–100, 103 TOC. See Time-of-occurrence Toronto conceptual schema, 203 Transposition errors in memory, 51 Traumatic experiences, memories of, 188–190 Tulving, Endel cue-dependent theory of forgetting, 8–9 divorce hypothesis, 133 model, 202

V

U

Y

Unconditioned stimulus, 226

Visual codes in memory, 116–119

W War of the Ghosts, The, 78–81 Weapon focus, 180 Word-list recall, episodic recall vs., 101 Working memory, 6–8, 10 cues in, 10 and LTM, 9 schema integration and capacity of, 134–135

Yerkes-Dodson Law, 178, 189

261