Infancy: Physical and Cognitive Development Chapter 3
The Expanding Brain n
Cerebral Cortex n n
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Outer furrowed mantle of brain Site of every conscious perception, action, thought Influences behavior a few months after birth Brain volume quadruples during first 4 years
The Expanding Brain n n
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Neurons formed during fetal period After birth, synaptogenesis occurs n Proliferation of connections at the synapses (often referred to as exuberant synaptogenesis) n Pruning follows Myelination: formation of fatty layer encasing axons n Visual cortex myelinated by 1 year n Frontal lobes, age 20 or beyond
Neural Pruning and Plasticity n
Plasticity: The brain is “plastic” (malleable) during early childhood before pruning is complete. n Plasticity allows other brain regions to compensate following injury. n Brain is less plastic following childhood.
Basic Newborn States: Reflexes Sucking
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Reflexes: Automatic responses or actions programmed by noncortical brain centers n Present at birth; promote survival n
Rooting
Grasping
Nutrition: Breast Milk •
Recommended for first 6 months ▫ ▫
Protects from diseases Correlational studies show that breast-fed babies: are more alert during first 2 weeks experience fewer gastrointestinal problems and middle ear infections are more resistant to colds and flu appear to be superior in later measures of intelligence in elementary school
Malnutrition: Developing World Concern n
Undernutrition: chronic lack of adequate food n
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Kwashiorkor: lack of protein, amino acids Micronutrient Deficiencies
Stunting: excessively short stature caused by chronic inadequate nutrition n
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Below 5th percentile in height for norms for their age Takes serious toll on cognition, health, and every activity of life
Stunted baby on left; normal baby on right
United States: Developed Country n
Food Insecurity n
Concern for lack of sufficient funds for food n
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Severe Food Insecurity n
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1 in 5 mothers report this fear 1 in 10 mothers report lack of food for children
See chart next page n
U.S. Federal Nutrition Programs for Children
Crying: First Communication Signal n
Crying: n n
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Lifetime peak at about 5 weeks Reflex dominated before the cortex is “on-line” at 4 months Vital to survival (responsive parenting is a must!)
Colic:
frantic, continual crying during first 3
months n Immature digestive system n May contribute to parental stress, but is temporary!
Intervention: What Quiets a Young Baby? n n
Pacifier, breast, bottle Swaddling n
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Kangaroo Care n
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Mirrors womb Hold close to body
Infant Massage n n
Calms infants Contributes to growth in premature babies
Swaddling
Sleeping: Main Newborn State n
Newborns, sleep 18 hours a day n 90% of time in sleep or drowsy state n
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Unlike adult sleep cycle, newborns drop immediately into REM sleep.
Wake every 3-4 hours 6 months, may sleep 6 hours a night 1 year, 12 hours a night and naps during day
Sleep Cycles
Brain-wave patterns and lifespan changes in sleep and wakefulness
Intervention: Self-Soothing n
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Bidirectional influences: Sleep deprivation contributes to irritability in both parents and the infant. By 6 months, upon waking, infants can self-sooth. What do experts suggest? n
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Erikson & Bowlby: sensitively respond to crying infant during first year Behaviorists disagree: Do not respond! Ultimately the decision is yours!
Sudden Infant Death Syndrome: SIDS n
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(1 in 1,000 in the United States); topranking cause of infant death in the developed world. Possible relationship with mothers who smoke during pregnancy Peak risk zone 1 to 10 months n
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Possible relationship with too few or too many neurons in area of brain involved in coordinating tongue movements and maintaining breathing airway
Reduce risk: n n
When infants sleeps, place infant on his/her back Keep away from fluffy bedding!
Sensory and Motor Development n
Hearing n
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Smell n
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In the womb, fetuses can discriminate different tones Within the 1st week, infants prefer smell of breast milk
Taste: n
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Infants stop sucking and wrinkle face in response to bitter, sour, or salty tastes Avidly suck on sweet solutions n Pain management technique - have infant suck on sweet substance
What Do Newborns See? n
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Researchers use the preferential-looking paradigm and habituation techniques Observe changes in the infant’s interest in a stimulus from extreme interest to habituation, and finally renewed interest to another new stimulus
Focusing on Faces n
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Newborns prefer faces to other stimuli, especially mother’s face Prefer attractivelooking people Infants mimic facial expressions
Newborns looked most at the face-like drawing. Are we biologically programmed to selectively look at faces?
Depth Perception: the Visual Cliff Experiment n
When 8 month-old babies begin to crawl, they perceive differences in depth and fear heights. n
Notice survival response!
Visual Cliff
Expanding Body Size and Motor Milestones n
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Growth is most pronounced in infancy, slows down during childhood, increases during preadolescence Motor Milestones n
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Cephalocaudal: lift head, pivot upper body, sit up, stand Proximodistal: control of shoulders before control of arms and fingers Mass-to-Specific: gross motor skills before fine motor skills n Importance of myelination
Contemporary View: Variations in Motor Milestones n
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Traditional view: motor milestones viewed as static stages (sit, crawl, walk) Contemporary researchers site variation among infant motor advances (e.g., belly-crawling, scooting, etc.). n Important: Rate at which babies master motor milestones has no relation to later intelligence. n Developmental disorders are the exception.
Intervention: Baby-Proofing, the First Person−Environment Fit n
Shape the home environment to fit the child’s developmental milestones. n
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View environment from baby’s perspective, then eliminate dangerous environmental opportunities. Create an environment suitable for exploration while keeping baby safe from harm. Anticipate and stay ahead of the developing child.
Cognitive Development: Piaget n n
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Stage Approach Studied his own children Schemas Assimilation Accommodation Adaptation
Circular Reactions: Sensorimotor Stage n
Repetitive action-oriented schemas (habits) n
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Through circular reactions, the infant explores and incorporates new information into existing schemas. Primary Circular Reactions n
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Secondary (about 4 months to 1 year) n
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The infant’s first habits (body-centered) Infant explores environment
Tertiary (begin about 1 year) n
“Little scientist” activities (baby explores the properties of objects)
When Infants Begin to Think: Sensorimotor Stage n
Evidenced by n
Deferred imitation: n
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Means−end behavior: n
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When infant repeats an action observed at an earlier time
Occurs about 1 year, when infant performs a different or separate action to reach a goal
Limitation in Thinking: A-not-B error: n
Approaching year 1, even though a baby sees an object hidden in a second hiding place, he/she returns to the originally viewed hiding place to find it!
Object-Permanence: Sensorimotor Stage n
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Understanding that objects exist even when out of sight Around 5-6 months, infants begin to look for hidden objects. At about 8 months infant develops object permanence (“littlescientist stage”).
Critiquing Piaget n
Infants understand basic principles about the physical world earlier than Piaget believed. n
By using preferential looking and setting up physically impossible situations, even young babies look surprised (“This cannot occur!”).
Critiquing Piaget and a New Perspective n
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Understanding of physical reality emerges gradually, not in unitary, qualitatively different stages as Piaget believed. New perspective: information-processing n A perspective on understanding cognition that divides thinking into specific steps and component processes, much like a computer
Emerging Infant Social Cognition n
Social Cognition: any skill related to understanding feelings and negotiating interpersonal interactions. n
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We make inferences about people’s inner feelings and goals, based on their actions. Research suggests this begins as early as 5 months.
Joint Attention n
This is the first sign of “getting human intentions” when a baby looks at an object to which an adult points or the infant follows a person’s gaze.
Language: Basic Principles n
Noam Chomsky’s nature-oriented concept: LAD, Language Acquisition Device Hypothetical brain structure that enables our species to learn and produce language n Unique to our human species n Chomsky’s concept is in opposition to Skinner’s nurture-oriented perspective. n
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We learn language by being reinforced for producing specific words.
Language: Basic Principles n
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The specific language learned is dependent on nurture—the place where you were reared. Presently, the social-interactionist view: Interactions between baby and caregivers— each wants to communicate, one encourages the other n Emphasis on the social function of language n
Language: Basic Principles n
Telegraphic speech n
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First word-combining stage
Infant-directed speech (IDS) (from caregivers) Higher-pitched, elongated vowels, and exaggerated tones attract baby’s interest. n Research suggests that IDS helps babies to master language. n
Infancy: Socioemotional Development Chapter 4
Attachment: The Basic Life Bond n
History Behaviorists (Watson, Skinner) minimized human attachment need n Believed “maternal reinforcing stimulus” created infant’s need to be close to caregiver n John Watson, strict behaviorist n
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Appeared hostile to the idea of attachment Crusaded against the dangers of “too much” mother love
Attachment: History n
Ethologists: early evolutionary psychologists n
Konrad Lorenz (1935): n Believed in a biologically programmed attachment response n Research with goslings – “imprinting”
Konrad Lorenz and his goslings (1935)
Attachment: History •
Harry Harlow ▫
(1958) Experiment with monkeys
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Separated babies from mothers at birth Found that contact comfort was important to bonding
John Bowlby ▫
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(late 1960’s)) Conducted clinical work with children who were hospitalized and separated from their mothers Promoted idea that a primary attachment figure is crucial to healthy development
Harlow: Baby monkeys clung to the cloth-covered mother
Exploring the Attachment Response n
Bowlby’s evolutionary-based theory Human beings have a critical period during the first year when the attachment response is programmed to emerge. n Proximity-seeking behavior—a survival response activated by threats occurring at any age n Two categories for threats to survival n
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May be activated by our internal state May be evoked by dangers in the external world
Attachment Phases n
Pre-attachment Phase—birth to 3 months n
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Reflex dominated time 2 months, social smile (example of automatic reflex, not in response to attachment figure) Social smile evokes care and love
Attachment Phases, continued n
Attachment in the making—4 to 7 months n
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Slight preference for caregivers, but still responds to everyone
Clear-cut (focused) attachment—7 to 8 months n
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Stranger-anxiety and separation anxiety appear Social referencing
Attachment Phases •
Working Model phase — ▫
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About age 3, child develops cognitive inner representation of attachment figure. When child is under stress, the need to make contact is very important. Responsive caregiver will fortify attachment bond.
The Strange Situation: Mary Ainsworth n
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Measures individual variations in attachment response during “clear-cut” stage Planned separations and reunions of child and primary caregiver
Ainsworth’s Attachment Styles n
Securely Attached n
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Child uses primary caregiver as a secure base from which to explore Child reacts with joy upon caregiver’s return
Ainsworth’s Attachment Styles n
Insecurely Attached n
Avoidant n
Appears detached; indifferent upon mother’s return
Ainsworth’s Attachment Styles n
AnxiousAmbivalent n
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Clingy, fearful, fear of exploration
Severe distress when mother leaves; contradictory emotions upon return; often inconsolable
Ainsworth’s Attachment Styles n
Disorganized Bizarre behaviors; may freeze, look frightened, may flee n Often result of abuse n
The Attachment Dance n
Synchrony n
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Caregiver and infant respond emotionally to each other in a sensitive, attuned way Ainsworth & Bowlby —parent’s sensitivity to baby’s signals are foundation for secure attachment
Attachment: The Caregiver n
Insecurely attached babies may have parents who: n n
misread signals may be rejecting, disengaged, or depressed
Attachment and Child’s Temperament n
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Temperament— characteristic behavioral style of approaching the world n Easy n Slow to Warm-up n Difficult Baby’s temperament and quality of caregiving will influence attachment style.
Caregiver’s Other Attachments n
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Synchrony with infant is difficult when other relationships are failing. Lack of support produces caregiver stress.
Is Infant Attachment Universal? •
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Universally, babies attach at about the same age. Secure attachment ratings are similar worldwide. Efe Tribe of Central Africa: ▫ ▫
Child has multiple caregivers Still attach at typical age to primary caregiver!
Infant Attachment—Does It Predict Later Development? •
Bowlby ▫
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Inner working model of attachment determines how we relate to others and feel about ourselves. Research supports this model.
Caution! ▫
Attachment styles can change over time! Life stress may change attachment from secure to insecure. Responsive caregiving can change attachment from insecure to secure!
Attachment: Summary •
Infancy is a special zone of sensitivity for our ability to form relationships. ▫
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Early attachment styles lay the foundation for what could be either healthy or unhealthy development.
Important: Attachment styles may change over time. Forces influencing attachment styles: ▫ ▫ ▫
Nurture provided by primary caregiver Infant’s temperament Other environmental forces
Settings for Development Poverty in the United States
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Poverty (Federal government definition) n
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An income level that allows a household to pay for shelter, food, and clothing, with a small amount left over. In 2009, more than 1 in 4 children under age 6 was living under the poverty line (see chart).
Low Income n n
Those earning within 200% of the poverty line. In 2009, 1 in 2 (44%) children
Poverty and Development: Research Findings n
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During childhood, poverty may compromise health (e.g., low birth weight, stressed mother). Poverty may have long-term educational impact. n
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Poverty during first 4 years of life makes it statistically less likely for a child to graduate from high school. May enter school “left behind” n
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Less access to quality preschools, enriching toys, trips to museums Less concrete breathing space to learn (e.g., substandard housing; dangerous neighborhood)
Interventions: Giving Disadvantaged Children a Boost n
Head Start Federal program offering high-quality day care and other services to children ages 3-5 from low-income families n Preparation for entrance to kindergarten n
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Early Head Start n
Federal program that provides counseling and other services to low-income parents and children under age 3
Impact of Child Care
Child Care and Development •
Options when mother returns to work ▫ ▫ ▫ ▫ ▫
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Spouse may stay at home Grandma or Grandpa Nanny, babysitters Family Day Care Day-Care Centers
NICHD Early Child Care Research Network (2006) ▫
Quality of parenting and attachment relationship at home outweigh time spent in day care.
Impact of Day Care NICHD study, continued n
Latest research: n Beginning early in life, long hours in day care predict an elevated risk of “acting out” behaviors until age 15. n NOTE! Correlations are weak!! n For certain at-risk infants and toddlers, high-quality day care can protect against behavior problems later.
Day care for infants and toddlers with employed mothers, late 1990s
Interventions: Choosing Child Care
Toddlerhood:
Erik Erikson’s
Age of Autonomy versus Shame and Doubt
Toddlerhood: 1-2 years n
Task of toddlerhood: to be autonomous selves n
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Understanding of “self” and self-conscious emotions appear May feel proud or ashamed Need to explore
Erikson’s negative outcome: Shame and Doubt
Toddlerhood: Socialization n
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The process by which children are taught to obey the norms of society and to behave in socially appropriate ways Self-regulation is difficult at age 2. Improves dramatically from age 2 to 4 n Exuberant, joyful, fearless toddlers more difficult to socialize! n
Do Shy and Exuberant Children Differ Dramatically in Self-Control? n
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Toddlers at the high end of the fearless, joyous, and angry continuum show less “morality” at age 4. Does power assertion work when disciplining? Better to redirect behavior and provide positive reinforcement
Providing the Right Temperament −Socialization Fit n
Shy n n
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Do not overprotect. Gently expose a shy toddler to new situations.
Exuberant n n
Develop a strong attachment bond. Resist power assertion.
Goodness-of-Fit: an ideal parenting strategy
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Arrange your child’s environment to suit his/her temperamental style. Minimize vulnerabilities. Accentuate strengths.