Bang!
The Brain Issue Oxford Science Magazine 10th Edition Hilary Term 2012
PhD in Complex Systems Simulation 4-year PhD fully funded studentships for 2012 Over twenty fully-funded PhD places are available at the Institute for Complex Systems Simulation at the University of Southampton. The Institute pursues world-leading complex systems research spanning the physical, natural, earth, social and life sciences, engineering, computer science, and mathematics. For our Doctoral Training Centre’s 2012 intake we are looking to recruit over twenty first-class graduates working on diverse problems from markets to oceans and brains to ecosystems. If you are interested in applying complexity science to some of the most challenging and relevant problems facing society, please get in touch. To find out more email: icss@soton.ac.uk www.icss.soton.ac.uk
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06/01/2012
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In This Issue 3. 4. 5. 6. 8. 9. 10.
Editorial News Gameshows & Goats David Attenborough Unprovable Truths Olbers’ Paradox Open Science
12. 13. 14. 16. 17. 18.
Hearing in Technicolour Split Brain Connecting the Dots Unconscious Decisions Exercise Your Brain Strictly Come Dancing
20. 20. 21. 21. 22. 24. 25. 26. 28.
NTE? OMG! Money For Old Lead Wood into Bone A Nobel Endeavour Bang! Talks to...Robin Ince The Naked Mole Rat Bacterial Cities Opinion: Nuclear Power Puzzle 1
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Editorial “How can a three-pound mass of jelly that you can hold in your palm imagine angels, contemplate the meaning of infinity, and even question its own place in the cosmos? Especially awe inspiring is the fact that any single brain, including yours, is made up of atoms that were forged in the hearts of countless far-flung stars billions of years ago. These particles drifted for eons and light-years until gravity and change brought them together here, now. These atoms now form a conglomerate- your brain- that can not only ponder the very stars that gave it birth but can also think about its own ability to think and wonder about its own ability to wonder. With the arrival of humans, it has been said, the universe has suddenly become conscious of itself. This, truly, is the greatest mystery of all.” – V.S. Ramachandran, The Tell-Tale Brain: A Neuroscientist’s Quest for What Makes Us Human Last term, Bang! took you on a journey into outer space. In this issue, we turn our attention a little closer to home. In fact, we turn it in on ourselves. We contemplate the brain’s attempts to comprehend the starry sky, and we look inside the organ itself — until we understand the instrument with which we sense our environment, we may never truly understand the universe in which we live. We explore the human brain, from the way it is wired to the fantastic multisensory experiences it yields. We see what happens when you cut it in two and how we can grow it with exercise. We even challenge our view of ourselves as conscious decision-makers. Join us as we plunge into the mysterious world of the mind. Kathryn Atherton and Jack Binysh Editors
Editors - Jack Binysh, Kathryn Atherton Deputy Editors - Kathryn Boast, Jai Juneja, Jack Sennett Creative Director - Anna Pouncey Layout Editors - Sofia Hauck, Nicholas Taylor Sub-Editors - Abu Abioye, Natalia Chetina, Gabriel Rosser, Isobel Steer Artists - Natalia Davies, Maria Demidova, Rebecca Giesler, Inez Januszczak, Ilse Lee, Clementine McAteer, Charlotte Mason, Emily Motto, Anna Pouncey, Catriona Sheil, Olivia Shipton, Susan Sun, Nicholas Taylor, Chloe Tuck Website - Lukasz Groszkowski, Paul Tsui Publicity and Distribution - Alan Stephen, Joanna Ellison Business - Boudewijn Dominicus
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Published by Oxford Student Publications Limited Chairman - Rohan Sakhrani Managing Director - Michael Kalisch Company Secretary - Morgan Norris-Grey Finance Director - Max Bossino Directors - Mark Brakel, Katie Chung, Alistair Smout, James Gibson, Isabelle Fraser Printed by Mortons Print Limited Copyright Bang! 2012
News More Power, Igor! Researchers at the University of Oxford have found that a brain stimulation technique called TDCS (transcranial direct current stimulation) can boost the brain’s ability to learn. In this technique, electrodes are placed on the scalp and a small electrical current is passed between them. The current changes the excitability of the brain tissue it passes through. When applied during learning, this equipment can enhance a variety of mental functions, including language skills and mathematical ability, and the effects can be long-term. This technology could offer hope for people with a range of neurological and psychiatric disabilities, but it also has the potential to boost healthy people’s brains – indeed, most of the studies have been done on healthy people. Given that TDCS is cheap, portable, painless and apparently safe, it has the potential to make a huge difference to society. However, Oxford neuroscientists have recently consulted ethicists within the university in an attempt to get a handle on the ethical
Malaria ramifications of these new discoveries. The major concern is over premature use of this technology. Once someone possesses the equipment, they will have the ability to use it whenever they like (even years later), as often as they like and on whatever cortical brain region they like (whether it has been previously tested or not). Crucially, it will not be possible to control who uses it, and the effects of TDCS on children’s developing brains have not yet been investigated. Furthermore, the potential side effects have not been fully explored. For instance, boosting one brain function may cause others to suffer. Nevertheless, this technique has massive promise. As Dr Roi Cohen Kadosh, a lead TDCS researcher from the Department of Experimental Psychology, says, “I can see a time when people plug a simple device into an iPad [to stimulate] their brain when doing homework, learning French or taking up the piano”. Kathryn Atherton
A new report indicates that twice as many people may die from Malaria as was previously believed, with figures as high as 1.2 million for 2010. The researchers reanalysed data from the past 30 years using new techniques that included correcting for bias from the misclassification of deaths — for instance, many deaths had been attributed to fevers rather than the underlying Malaria. This work also overturns the conventional belief that the vast majority of malaria mortalities are in children under five. Instead, the study found that 42% of deaths were of older children and adults. Nevertheless, the research confirms the downward trend in the number of deaths that was found by the World Health Organisation, suggesting that efforts to tackle the disease are having an impact. However, much more needs to be done if malaria is to be finally eradicated. Kathryn Boast
Dude, Where’s My Boson? Following news conferences at CERN, unpublished reports of ‘tantalising hints’, and an enthusiastic barrage of media coverage, the question remains: did the LHC find the Higgs boson or not? The short answer seems to be not yet, though two experiments at the LHC, called ATLAS and CMS, have made significant progress towards pinning down the elusive particle. “We have restricted the most likely mass region for the Higgs boson to 116-130 GeV”, said Fabio Gianotti, spokeswoman for ATLAS, “and over the last few weeks we have started to see an intriguing excess of events in the mass range around 125 GeV.”
However, most scientists consider these hints too weak to constitute actual evidence, with the spokesman for the CMS, Guido Tonelli, urging caution: “As of today what we see is consistent either with a background fluctuation or with the presence of the boson. Refined analyses and additional data delivered in 2012 by this magnificent machine will definitely give an answer.” With ATLAS and CMS formally publishing their results, and the promise of another year’s worth of data still to come, it is hoped that 2012 may be ‘the year of the Higgs’. Jack Binysh
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Art by Natalia Davies and Chloe Tuck
Gameshows & Goats You’ve goat to be kid-ding me
“Hello contestant and welcome to the show! Tonight’s challenge is nothing more than two simple choices, but pay attention or you may end up leaving with nothing.” The audience cheers loudly as you walk to a podium opposite three doors. The host cracks a winning smile and explains the rules of the competition. “You get to choose a door, whichever one you like, and when we open it you win whatever is behind that door. Behind one is tonight’s Grand Prize but behind the other two are goats.” “But there’s a twist! I know where the Grand Prize is hidden. Before we open the door you’ve chosen, I’ll open one of the two doors you didn’t pick, containing a goat. I’ll then give you the chance to switch your choice to the other unopened door or stick with your original decision.” Without further ado you pick door 1. The host winks and opens a different
caused quite an uproar. She claimed that contestants’ chances of winning the Grand Prize would double if they switched — an assertion which upset professional mathematicians across the world. The column received One contains the “It highlights how thousands prize and the other easily our intuition of letters contains another can be tricked” insisting that goat. That’s all there her conclusion is to it. Whether was incorrect you switch or stick, and that she accept this in light of such there’s just a 50:50 chance, right...? overwhelming opposition. door to reveal a scrawny-looking goat. The audience goes wild with a mixture of “Switch!” and “Stick!”. Your gaze flicks between the two remaining doors.
SWITCH OR STICK?
This conundrum is known as the ‘Monty Hall’ problem, named after the American TV presenter who hosted a show with a similar competition. The answer seems simple: the contestant now has a choice between two doors, one with a Grand Prize behind and one with a goat. How could the probabilities be anything other than 50:50? When columnist and author Marilyn vos Savant answered this question in a 1990 issue of PARADE magazine, she
Switch equals win
In fact, her answer was correct! This can be demonstrated by considering the possible outcomes of sticking or switching once a door is chosen. For the sake of argument, let’s say the contestant picked Door 1 first. As illustrated, if the contestant switches, he has a 2/3 chance of winning, while sticking gives him only a 1/3 chance of winning. This is because there is a 2/3 chance that the contestant originally picked a goat (in which case he must switch to win) and only a 1/3 chance that he originally picked the Grand Prize (in which case sticking would lead to a win). Fortunately for vos Savant, the tide of opinion began to turn after maths classes across America ran the experiment and reported the outcomes. By the end of an unprecedented fourissue-long debate on the Monty Hall problem, she was happy to report that almost all readers had changed their view.
Switch equals win
The ‘Monty Hall’ problem is an example of a veridical paradox: the solution is counter-intuitive, but can easily be demonstrated by performing an experiment. It highlights how easily our intuition can be tricked. Though it may not have been obvious at first, it’s now clear that switching is always the right thing to do. Unless, of course, you’d prefer to win the goat.
Switch equals loss Chosen Door
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Charlie Hornsby is a 2nd-year undergraduate at Oriel College, studying Chemistry. Art by Catriona Sheil.
David Attenborough An extraordinary life
When it comes to national treasures, few glitter as wonderfully as Sir David Attenborough. An iconic figure on British television screens for nearly 60 years, he is held dearly in the hearts of many for bringing the beauty of the natural world into our living rooms. But what is more endearing than his ground-breaking series of programmes is the man himself, and how his love of zoology has led to his extraordinary life in front of the camera. The latest jewel in his collection, Frozen Planet, has become cult viewing for young and old alike.
Early Years Born in West London on 8th May 1926, Attenborough grew up fittingly surrounded by academics at the University of Leicester. His father Frederick, a noted British academic, was principal of the College House there. David’s love of biology and natural history blossomed early, and by the age of seven he had his own collection of old stamps, fossils and specimens. Encouragement for his hobby came from an unlikely source: the young academic and famous archaeologist-to-be Jacquetta Hawkes, who was introduced to him by his father. She was so impressed by the young boy’s collection that she kept
in contact, sending a box of fossils, dried seahorses and tiny artefacts to add to his museum. Another gift from one of his adopted sisters provided further inspiration. It was a piece of amber containing numerous prehistoric creatures, so influential that it later became the focus of his programme, The Amber Time Machine. Following his early education at Wyggeston Grammar School for Boys, Attenborough continued to nurture his love for nature at Clare College, Cambridge, where he studied Natural Sciences on a scholarship.
Entering the World of Work David was reluctant to become an academic. Averse to the idea of being stuck in a lab or lecture theatre for the rest of his life, he took up a job editing children’s science textbooks. Feeling unfulfilled by this position, he soon jumped at the opportunity to apply to the BBC after reading a job advertisement for a radio talks producer. He was rejected at first, but his CV finally caught the attention of Mary Adams, head of factual broadcasting at the BBC’s fledgling television department. Having seen only one television programme in his entire life, Attenborough was slightly sceptical of this new department. He
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nevertheless agreed to a 3-month training contract, joining the BBC full-time in 1952 and becoming part of Europe’s only television studio. So began what would prove to be a lifechanging relationship between David and the BBC.
Too Big for TV The directors at the BBC initially thought Sir David’s teeth were simply ‘too big’ for him to work in front of the cameras. However, his talent and hard work meant he rose rapidly through the ranks of the department. Indeed, he was soon given an opportunity to co-present The Pattern of Animals with naturalist Julian Huxley. Though the show itself was deemed ‘stuffy’, the programme’s use of animals from London Zoo introduced Attenborough to Jack Lester, the curator of the Zoo’s reptile house and a fellow animal fanatic. Passionate about producing a more hands-on show about animals, the pair developed Zoo Quest in 1954. At the last minute, Lester, who was meant to be presenting the show, fell ill, giving Attenborough a further chance at presenting. These were the humble beginnings of Sir David’s
long reign producing and presenting natural history programmes for the BBC. 1957 saw the creation of the BBC’s Natural History Department in Bristol, but Attenborough turned down a position there, reluctant to move his young family from London. Instead, he formed his own Travel & Exploration Department in London, which allowed him to continue presenting Zoo Quest and begin work on other shows. Ever eager to continue his pursuit of learning, Attenborough left the BBC briefly to study for a postgraduate degree in social anthropology at the London School of Economics, although he returned when offered the position of Controller at BBC2.
Now, nine series of Life, a couple of honorary doctorates and dozens of awards later, Sir David Attenborough is revered worldwide as the father of nature documentaries. “His mission is about communicating this fascination with animals” says Martha Holmes, series producer of Life. As he prepares to mark the 60th anniversary of his career in wildlife broadcasting, his
fascination seems far from dwindling. What next? “Going to more places, learning more?” asked Samantha Weinburg in a recent interview. “Having fun,” he replied, “It always has been.”
Life at the BBC Sir David has always been an advocate of television, recently remarking that technological development has permitted “humanity in [his] generation [to see] more than any human being in history”. He made it his mission as BBC controller to shake up the schedule and release novel programmes, commissioning classics such as Match of the Day and The Likely Lads. His huge influence on the development of television in Britain secured him the role of Director General of the BBC. However, it was his documentaries which truly held his passions, and his return to presenting in the early 1970s led to the BBC signing the co-production deal for Life on Earth. With mind-blowing footage and using innovative film-making techniques, Attenborough’s hugely successful programme was watched by over 500 million people and set a benchmark in nature documentaries.
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Holly Youlden is a 2nd-year undergraduate at Keble College, studying Biological Sciences. Art by Olivia Shipton. Portrait by Anna Pouncey.
Unprovable Truths
How one man shook the foundations of maths In the early twentieth century, it seemed an enormous victory for mathematics had been achieved. Russell and Whitehead had just published their Principia Mathematica, a comprehensive attempt to reduce all of mathematics to a system of axioms (propositions taken to be fundamental truths) and rules of inference from which every true statement in mathematics could be systematically generated; the role of a mathematician would be to interpret the results. However, while the Principia Mathematica was an ambitious undertaking, it could establish neither its own consistency (that it would never contradict itself) nor its own completeness (that it would generate every truth of mathematics). Their work was an attempt to rise to a set of challenges that the great mathematician David Hilbert believed must be addressed before mathematics could be considered above reproach. Despite the apparent flaws, Hilbert himself considered the issue essentially resolved. He believed the consistency and completeness of the Principia Mathematica would be proved with time, removing any doubts about the validity of mathematics.
GÖDEL’S PROOF
This calm state of affairs was shattered in 1931 when Gödel, an Austrian mathematician, published his Incompleteness Theorems.
His first theorem states that any A sentence could then use another’s consistent system of mathematics Gödel number to refer to it. For which is powerful enough to include example, a sentence that means ‘this basic arithmetic (and to perform number is the Gödel number of an maths as we know it, we need axiom’ can be constructed. arithmetic) will be unable to prove some true sentences of mathematics. However, this alone was not enough To make matters worse, one of to construct a self-referential these unprovable sentence, and Gödel sentences will always then had to prove a be “this system complicated result “This sentence is consistent”. called the Diagonal cannot be proved” The system can Lemma to show that never prove its such sentences even own consistency. With this one exist. Only then could he begin to theorem, Gödel doomed the Principia construct the sentence required for Mathematica to failure, along with his Incompleteness Theorems. any other attempt to satisfy Hilbert’s challenges. OUT OF REACH Gödel’s result seems at first glance The content of the first to be very negative ‑ we are explicitly incompleteness theorem is elegant shown that we will never be able to and uncomplicated. Gödel simply encapsulate mathematics in a system constructed a sentence equivalent amenable to human comprehension. to ‘this sentence cannot be proved’. However, many find this fact If such a sentence is provable, then liberating. It is a guarantee that the system proves false sentences mathematics will never be reduced and a contradiction can be derived. to mere computation and will never If this sentence cannot be proved, cease to be a source of astonishing it is an example of a true sentence and counterintuitive truths. Many that cannot be proved. Note that, would go even further, and say that here, ‘prove’ is taken to mean ‘prove it provides a suggestive argument from the axioms and rules of a given for mathematics being discovered system’. and not invented. No matter how comprehensive our system of The sentence discussed above, mathematics seems, there will always called a Gödel sentence, refers to be a Gödel sentence just out of reach, itself. This is not something that true by brute fact but inaccessible to is obviously possible using the all methods of proof at our disposal. language of mathematics ‑ sentences of mathematics seem to refer only Alexander Wickens is a to mathematical objects, such as Mathematics and Philosophy numbers. The first step Gödel had to alumnus of Pembroke take was constructing sentences that College. refer to other sentences, a problem Art by Susan Sun. he neatly solved by labelling each sentence with a positive integer called the Gödel number of that sentence.
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Olbers’ Paradox Shedding light on dark skies Why is the sky dark at night? Posed by German astronomer Heinrich Olbers in the 19th century, this devastatingly simple question appears surprisingly difficult to answer when you think about it. If you point your finger at anywhere in the sky then you are guaranteed to be pointing at a star, so you might expect the sky at night to be really rather bright, yet we look at the sky at night and find that it is not.
This means the universe is neither eternal nor infinite nor static. So not every line of sight ends in a star and there are stars whose light has not yet had time to reach us.
A NEW PROBLEM
This would seem to solve Olbers’ paradox, but the Big Bang theory introduces a new paradox of its own. In the very early universe, the energy everywhere was so great that atoms couldn’t form — there was a soup of Olbers assumed that the universe atomic nuclei and electrons. As the is eternal, static (not expanding or universe cooled, electrons fell into contracting), and infinite. Since the the electron shells of the nuclei to universe is infinite and roughly the form atoms during same in all directions a time known as the (isotropic), every line The sky is bathed in Recombination era. of sight ends in a star. light we cannot see When electrons fall Since the universe into electron shells, is eternal, the stars’ they emit light. Thus light has had eternity the entire universe was bathed in to permeate the universe so you are very bright light, which should still be guaranteed to see it. Therefore the visible today. But where is it? This new sky will be bright at night. But it’s an paradox can be solved by taking into easy night-time experiment to see that account the fact that the universe is the sky is dark, so some or all of the expanding. To see how this solves the assumptions must be wrong. paradox, we must first understand what ‘expanding’ means. With our current theory, the Big Bang model, we Imagine a balloon with some small believe that all of these pieces of paper stuck to its surface. As assumptions are false: you blow up the balloon, the universe is 13.7 its surface stretches billion years old and and the distance expanding at an between the pieces of accelerating rate.
“The Big Bang Theory introduces a paradox of its own” paper increases. This is a good analogy for the expansion of the universe. The fabric of space is stretching, so that galaxies are moving away from each other. Note that the two points aren’t moving apart from each other through space but that the space between them is expanding. Now draw a wavy line between two pieces of paper on the balloon. You will notice that the wavelength of this wave — the distance between its peaks — gets bigger as the balloon expands. We can think of this wave shape as representing a wave of light. Any light that was emitted at the Recombination era (and indeed since) has had its wavelength increased by the expansion of the space it has been travelling through. The light will have travelled through a lot of space, so its wavelength has been increased beyond the range of human vision. The sky is in fact bathed in light, but light invisible to our eyes – the Cosmic Microwave Background, discovered in the 1960s by Penzias and Wilson. Until 50 years ago, we had no adequate explanation of why the sky is dark at night. Even now, our current understanding of the universe is riddled with uncertainties, problems Olbers himself would never have dreamed of. Deceptively simple questions force us to think hard about the obvious facts we take for granted every day, and make us realise that often they aren’t obvious at all. James Wills is a 1st-year undergraduate at Brasenose College, studying Physics and Philosophy. Art by Charlotte Mason.
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Open Science
Bang! takes a look at the issue of open access Open Science is a big idea with a simple aim: to place scientific literature, research tools, and data in the public domain to increase the transparency of research and promote the sharing of scientific results. It has the potential to foster scientific discovery and conversation, not only within the scientific community, but also in the general public. The idea is not without its flaws. Open Science has consequences regarding the way scientists are credited for their work, and there is no consensus on an appropriate funding model for the publication of scientific research. Yet efforts continue to be made to widen public access to published literature and several important projects that engage the public in the scientific process have begun. Open Science is becoming more mainstream, but not without controversy.
Scientific Publishing and Open Science One of the biggest talking points within Open Science is the question of public access to scientific research. Traditionally, researchers have submitted their findings to peerreviewed journals for publication. The published article is then accessible either through an institution’s subscription to the journal, or by purchasing the individual article directly, which typically costs around £20. Costs of yearly subscriptions to journals have increased substantially, and British university libraries have had to increase the amount spent on journals from 50% to 65% of their budget over the last 10 years. As a consequence, libraries have had to cancel subscriptions to many other publications, and are purchasing fewer scientific essays. In contrast to this subscription model, open access publication allows free distribution and access to published articles. There are no subscription fees or price barriers to access. In the self-archiving open access model, authors directly submit a version of their paper to a repository or website, bypassing the need for a publisher entirely. The article is freely available but may not have been peer-reviewed. One of the most successful examples of this method is ArXiv, a self-archive for preliminary versions of papers (preprints) from the fields of mathematics, physics, astronomy and computer science, which has been in use for over 20 years.
Another form of open access publishing subscription based journals, but it is not involves the publishers providing free yet clear whether this translates to a access to their journal papers on their greater number of citations. websites. To fund this access, the authors may be charged a publication The difficulty and controversy fee, or revenue may come from surrounding Open Science, and in advertising. These open access models particular open access publishing, has are used by journals that publish entirely recently been highlighted by a proposed open access work as well as hybrid bill in the US called the Research journals that are subscription-based Works Act. The National Institute of but offer open access options for a fee. Health (NIH), an agency of the US There are fears that the large publishing government, currently has a policy that fees imposed by ensures the public some journals for has free online open access will Open Science has the access to all of the render smaller potential to foster research it funds institutions and those scientific conversation within 12 months in developing nations and discovery of publication in unable to afford the peer-reviewed fee to publish in open journals. In a move access journals. These concerns will that could be seen as a direct attack on need to be addressed for such open the principle of Open Science, US law access models to move forward, as makers have proposed a bill that would the attempt to improve access may prohibit the NIH’s public access policy actually limit the contributions of poorer from continuing. The Research Works institutions to research. Act is backed by the Association of American Publishers, who have made An important established currency in substantial profits from subscription scientific publishing is the citation — a journals for years and would like to reference from one article to another. protect their franchise against the less The quality of a scientific journal is profitable open access model. While judged on its impact factor: the average this Act is a challenge to Open Science, number of citations its papers receive. it may have the unintended effect of Researchers are very concerned about galvanising researchers and libraries the impact factor of their chosen into united action. Proponents of Open journal and the number of citations Science have called for researchers to their work receives because these publish only in open access journals and are critical factors in the success of a for libraries to cancel their subscriptions scientific career. Papers published in to traditional journals. A petition to peer-reviewed open access journals are support this boycott is growing with downloaded more often than those in increasing speed.
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Researchers and Open Science Proponents of Open Science argue that it encourages collaboration between scientists by improving their access to one another’s findings. Researchers are now able to post early results, lab techniques, and even experiments that did not work online. While this may speed up scientific
progress, there are potential risks for the researchers. In fast-moving and competitive fields, being the first to publish new findings is key to securing patents, funding and tenure, so scientists who share their work may be risking their future careers. A high-profile example of improved
collaboration fostered by Open Science comes from the recent Italian OPERA experiment, which provided contentious evidence that neutrino particles can travel faster than light. The researchers publicly requested scrutiny of their results from the broader particle physics community and posted a pre-print on ArXiv.
The General Public and Open Science The desire to open up the scientific process also extends to the involvement of the general public. In a recent example, paleoanthropologists working on fossils of the hominid Australopithecus sediba have proposed a collaborative research effort where members of the public can contact the researchers with ideas on how to determine the identity of preserved skin on the fossils. These individuals may eventually have the opportunity to participate directly in the research and co-author papers. Additionally, with the use of the Internet, surveys and questionnaire data can now be collected on a global scale. The BBC’s LabUK website invites the public to engage in the research process by participating in online experiments designed in collaboration with scientists. LabUK summarises their results on the website and aims to publish them in peer-reviewed journals. The Internet has also provided a means for the public to assist with scientific classification and analysis. Galaxy Zoo is an online astronomy project where the public can help classify galaxies from the Hubble Telescope survey, and is part of the larger Zooniverse that hosts a variety of scientific research projects that individuals can participate in. One of the strongest motivations for Open Science is the fact that much of the research conducted in the UK is publicly funded. Proponents argue that the public, including both the general community and the scientific community, has a right to access, examine, and use the research conducted with their money.
Science 2.0 Science 2.0, a website community devoted to sharing science, described their Open Science vision with the words, “Collaboration, communication, participation, and publication”. This description makes clear the benefit of the Open Science model. Collaborations between scientists can increase understanding and lead to innovations. And in order for science to continue to grow and be funded, the public needs to be familiar with
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science and value its place in society. The issue of Open Science is becoming increasingly urgent, yet the conflict between the business of scientific research and the inherent value of the knowledge it can yield may be difficult to resolve. There are clear practical challenges to implementing some of the requisites, but it is a concept that should be examined in detail, hopefully to the benefit of all. Nancy Rawlings is a postdoctoral researcher at the John Radcliffe Hospital. Art by Ilse Lee.
Hearing in Technicolour Synaesthesia: a fusion of the senses What if you could get two senses for the price of one? Imagine that the text you are reading is a bright mosaic of colour, or that music contorts itself into fantastical shapes, unbidden, before your eyes. Imagine the months of the year inhabiting a 3D ellipse around your body, or some words tasting of chocolate, and others of earwax. For the small percentage of people with synaesthesia, these seemingly impossible experiences are a reality. Synaesthesia literally means ‘joined sensations’ – an apt name, as it describes a condition wherein stimuli in one sensory or conceptual category evoke an automatic sensory experience in another. Most synaesthetic experiences are strikingly specific – a synaesthete would see shiny royal blue rather than just blue. These associations tend to stay fixed from childhood. Prevalence of different types of synaesthesia varies immensely; word-taste synaesthesia, for example, affects an almost negligible percentage of people, whereas about 1.5% of us have grapheme-colour synaesthesia (in which letters and numbers are seen as having specific colours), and sequencespatial synaesthesia (where individuals automatically visualize numbers or time denominations, such as months, in a particular layout in space) may affect up to 20% of the population. Synaesthesia is not a modern discovery, but it was not until the late 1800s that the phenomenon first made inroads into the scientific literature. Now,
after nearly a century of subsequent obscurity, the recent rise of cognitive psychology and advent of neuroimaging techniques have rekindled interest in a topic once considered merely speculative.
on structure and one on function. The ‘cross-activation’ model posits that synaesthesia arises from abnormal brain wiring, and indeed several studies show synaesthetes to have increased white matter, indicating connectivity, in brain areas involved with certain IS IT REAL? senses. This could be a consequence Nowadays, the intensely introspective rather than a cause of synaesthesia, nature of synaesthesia still poses however. On the other hand, the problems for scientific inquiry. For ‘disinhibited feedback’ model proposes starters, how do we know synaesthetes’ that synaesthesia arises from atypical reported experiences are real, without regulation of neural circuits that govern experiencing them ourselves? Studies senses. As this model does not involve using imaging techniques such as fMRI special neural hardware, it fits well have revealed activation of V4, the main with claims that hallucinogens produce brain region responsible temporary synaesthesia. for colour processing, Ultimately, it may be that “We may all be when grapheme-colour both models are correct, synaesthetes to synaesthetes view purely each describing different some extent” greyscale graphemes. aspects, types, or Grapheme-colour degrees of synaesthesia. synaesthetes have also been shown to outperform ordinary people in tasks Other clues, too, can help us to where synaesthetic colours might help, determine how synaesthesias are such as visually searching for a single formed. Although each synaesthete’s 5 in a background of 2s. Furthermore, experiences are idiosyncratic, there synaesthetes perform worse at tasks in are some intriguing trends across which synaesthesia interferes, such as synaesthetes. For instance, the letter ‘A’ naming letters printed in colours that has an above-chance likelihood of being contrast with what they synaesthetically red, and food words tend to taste like see. the food they describe. Despite scarce direct evidence as to how synaesthetic HOW DOES IT ARISE? associations are formed, findings like The next major question is how these suggest that they may derive synaesthesia arises. Genetic studies partly from shared cultural knowledge, suggest that a general predisposition such as linguistic meaning. to synaesthesia is probably hereditary, although specific forms Perhaps most intriguing is recent are not. Although the neural basis of research suggesting that we may synaesthesia is not definitively known, all be synaesthetes to some extent. there are two main theories, one based Studies asking synaesthetes and non-synaesthetes to assign colours to musical tones found that both groups consistently matched lower pitches to darker colours. Amazingly, this basic finding has been replicated in chimpanzees, suggesting that this innate tendency towards cross-sensory perception may derive from our distant evolutionary ancestors. Far from being an odd neurological disorder, synaesthesia may be more deeply rooted in us than we guessed.
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Jackie Thompson is a 2nd-year DPhil student at Lincoln College, studying synaesthesia. Art by Ilse Lee.
Split Brain In two minds
“No symptoms follow its division. This simple experiment at once disposes of extravagant claims to the function of the corpus callosum.”‑ Walter E. Dandy Dandy, an American neurosurgeon, was describing an operation he performed in 1936 – a surgical cut through the rear part of the corpus callosum. Viewed from above, the brain is like a walnut: it has a left and a right hemisphere, which are linked by a thick nerve bridge – the corpus callosum. While the corpus callosum is not the only route by which information can pass between the left and right hemispheres of the brain, its 250 million nerve fibres are the key means of communication between the two halves of the cerebral cortex. Cutting through the corpus callosum is tantamount to cutting the brain in half. One might imagine that this would be fatal (and if you cut the brain in half from any other angle, it probably would be), but remarkably, people not only survive ‘corpus callosotomy’, but often do so without displaying any obvious change in behaviour.
SPLIT-BRAIN SYNDROME
The outcome of a total corpus callosotomy (most commonly used as a last-resort treatment for epilepsy) is known as ‘split-brain syndrome’. While split-brain patients appear completely normal, careful study has revealed something astonishing: both hemispheres of people with split brains continue to operate, but largely independently. It seems that people with split brains have two separate minds – and presumably two separate seats of consciousness.
SEPARATE HEMISPHERES
Much of the early research into split-brain syndrome was conducted by Roger Sperry and his graduate student, Mike Gazzaniga. Due to the crossed-over wiring of the optic nerves, it is possible to send information selectively to the right or left hemisphere of a split-brain patient by presenting objects confined to either the left or right half of visual space*. Sperry and
? Gazzaniga used this technique to confirm that many brain functions are lateralised (i.e. localised to one hemisphere). For example, language is mainly processed by the left hemisphere. When you speak to a person with a split-brain, you are conversing with their left hemisphere only. Flash a picture to the left of them (seen by the right hemisphere), and the person being tested will verbally claim to have seen nothing at all. However, when asked to draw what they saw with a pen held in the left hand (controlled by the right hemisphere), they will draw the picture that was shown. Experiments using this method have demonstrated that while some abilities are largely confined to one hemisphere, both hemispheres are capable of, in Sperry’s words, “perceiving, thinking, remembering, reasoning, willing, and emoting, all at a characteristically human level”.
NEW QUESTIONS
Work on split-brain syndrome poses provocative questions about the unity of consciousness and the nature of the self. It has also led to new proposals about hidden functions of the undivided mind. For example, when testing split-brain participants, Gazzaniga noticed something strange. When the right hemisphere draws a flashed image (e.g. a bell) that was not shown to the (verbal)
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Only right hemisphere sees picture. Patient reports seeing nothing (since language in left hemisphere), but draws picture with left hand (controlled by right hemisphere).
left-hemisphere, the left-hemisphere will often come up with a plausible – but necessarily fabricated – story about why the left-hand drew a given picture (e.g. “I drew a bell because I heard bells before coming into the testing suite.”). Gazzaniga suggests that the left hemisphere is home to an ‘interpreter module’ that constantly attempts to retrospectively construct a story about the chain of events we experience. When the interpreter is blind to the actual causes, it constructs something plausible. This behaviour – termed ‘confabulation’ – is found in other clinical conditions, and in certain circumstances can be seen in normal individuals. Other researchers have argued that it’s hard to disentangle the lateralisation of language and the localisation of the postulated interpreter. The right hemisphere could be doing this too – it just can’t talk about it. Indeed, split-brain syndrome has produced as many fundamental questions as it has answered. Scientists are using all the disparate tools of neuroscience and psychology in the hope of answering them. *Follow http://tinyurl.com/BangSplitBrain to see Gazzaniga testing a patient using this technique. George Wallis is a 2nd-year DPhil student at New College, studying the neuroscience of working memory. Art by Nick Taylor.
Connecting the Dots in your Brain Scientists have been baffled by the complexity of the human brain for centuries. The arrival of non-invasive functional neuroimaging in the 1990s afforded them an unprecedented glimpse into the brain’s inner workings. However, this technology was initially used in a misguided attempt to map faculties of the mind onto individual brain structures. We now realise that our brain regions are not islands, but instead work together in networks. Understanding how they are wired together and how they communicate with one another holds the key to understanding how the brain functions. Several new techniques have made it possible to study connectivity in live human brains.
Anatomical Connectivity Neuroimaging Information is sent from one brain region to another via bundles of nerve fibres known as ‘white matter’. Knowledge of how the brain is ‘wired’ would represent a huge step in understanding how the brain works. Investigating the brain’s connections has long been restricted to the injection of tracers into the brains of experimental animals, which may have different wiring to humans. However, a new technique known as diffusion tensor imaging (DTI) allows us to see the wiring in the human brain using an MRI scanner. DTI works by looking at the diffusion of water molecules in the brain. As water diffuses more freely along white matter fibres than across them, DTI can tell us about the orientation and structural integrity of white matter tracts in the live human brain. DTI will not only provide a wiring diagram, but will allow us to identify whether abnormalities in connectivity underlie certain neurological conditions. It also raises the possibility of relating genetics and environmental influences to individual differences in brain circuitry. Most interestingly, DTI could be used to reveal links between individual differences in wiring and behaviour. DTI has even shown that the circuitry of the adult brain is sculpted by new experiences, such as learning to juggle.
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Functional Connectivity Brain Imaging
Brain Stimulation
Functional (as opposed to structural) brain imaging gives us information about brain activity. Traditionally, it has been used to identify which brain regions are active when we engage in particular cognitive processes. However, we can use the same data to investigate which brain regions are talking to each other. If two areas of the brain are interacting, their activity will correlate over time. Therefore, analyses that reveal which brain areas have correlated activity can give us insight into the functional networks that underlie a particular behaviour.
In transcranial magnetic stimulation (TMS), an electromagnet held against the scalp induces a current in the brain tissue beneath it. TMS is often used to ‘scramble the signal’ in a brain region, temporarily simulating local brain damage in healthy subjects. However, it can be used in another way. A single pulse of TMS will cause the nerve cells below the electromagnet to ‘fire’. This technique can be used to assess how stimulating one brain area affects the activity in another, which will depend on the functional connectivity between the two regions. In paired-pulse TMS, a second pulse is used to measure the change in brain activity caused by the first. The second pulse is delivered to a brain area that produces a measurable output. Typically this is the part of the brain (within an area known as M1) that is responsible for motor control of the hand. Stimulation here produces a visible muscle twitch. The greater the excitability of the nerves in M1 at the time that the second pulse is delivered, the larger the muscle twitch. If the first pulse is applied to a region that is communicating with M1, it will modulate M1’s excitability, affecting the magnitude of the muscle twitch.
It is natural to try to divide the brain up into sections and ask what each of them does – indeed, Franz Joseph Gall, the late 18th century father of ‘phrenology’, claimed that complex traits like conscientiousness and constructiveness are entirely supported by individual brain regions, which expand with use, producing bumps in the skull that can be felt with the fingertips! Over two centuries later, we are beginning to realise that while specific brain regions may be specialised for elementary processing operations, they must work together to produce complex behaviour. The latest non-invasive techniques are giving us an insight into how this is achieved. Soon, we will have a much greater understanding of our brain’s connectivity and ultimately of ourselves. Kathryn Atherton is a 2nd-year DPhil student at New College, studying Neuroscience. Art by Anna Pouncey.
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Unconscious Decisions Are we really conscious decision-makers? Most of us would defend the claim that we humans are free agents, in that we make our own conscious decisions about how to act. Indeed, the idea that humans are conscious decision-makers is central to many aspects of modern life, such as the justice system and religious beliefs. Recent developments in neuroscience, however, have challenged this intuitive notion that our actions are based on conscious decisions.
DECIDE TO ACT FIRST, THINK LATER
The seminal study in this area was carried out by Benjamin Libet and his colleagues in 1983. Libet had subjects watch a clock-like display, around which a dot rotated every 2.56 seconds. All the subject had to do was flex their fingers, whenever they liked, but taking note of the dot’s position on the clock at the time they made their decision to perform the movement. Scalp electrodes were used to measure their brain activity while they performed this task.
Libet’s Findings A plot of brain activity against time
Brain activity predicting action begins
The experimenters found that specific patterns of activity in two brain areas (the frontopolar cortex and posterior cingulate) predicted whether subjects would make a left or right response up to ten seconds before subjects reported making a decision.
The core issue that these studies Libet found that electrical activity in identify is that there appears to be certain areas of the brain not only some decision-making process going preceded the subjects’ movements, but on in our brain before we are actually was also apparent aware of the before the dot had decision itself. If reached the recalled Decisions seem to be this is the case, position. That is, made before we are can we really there seemed to actually aware of them be conscious be neural activity decision-makers? predicting the It would appear movement before the subjects had that by the time we feel we make a made a conscious decision to move – in conscious decision, it has in effect this case it appeared to precede the already been made for us. decision by at least three tenths of a Many commentators have claimed that second. these results should be viewed with These findings were not without scepticism, questioning the reliance on controversy, but there is a wealth self-report data and the over-simplistic of more recent studies that use nature of the experiments. But what updated methods to come to similar if they had found brain activation conclusions. In a 2008 experiment, only after a decision was made? On Soon and colleagues used fMRI to the surface, this might seem more in scan subjects while they watched a keeping with our view of ourselves as screen displaying a letter that changed conscious decision-makers. But such a regularly. Whenever they liked, the result would in fact be more alarming, subjects had to decide to press a because it would provide no explanation button with their left or right hand, for where that decision came from. remembering which letter was on the screen when they made their decision.
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Conscious intention to act
Action
That is, it would suggest that there was a ‘ghost in the machine’, separate from the brain, which was responsible for decision-making. When viewed from this perspective, it seems to make perfect sense that our conscious decisions arise from some form of brain activity.
THE ILLUSION OF WILL
On the basis of these studies, the psychologist Daniel Wegner has argued that free will is an illusion. We think something and then perform an action, and it seems to us that we are acting because of that thought. But Wegner proposes that this feeling of causation is a trick of the mind. In fact, both the thought and action are caused by unconscious neural activity, and are not directly related. The idea that there is some kind of ethereal ‘self’ that makes a decision before the brain acts on it simply makes no sense from a neuroscientific perspective. This ‘self’ is really just a product of the same neural activity that makes the decision. Wegner’s theory is itself controversial, but it is hard to see how else decisionmaking could occur. In any case, it is clear that advances in neuroscience highlight how intuitive notions about ourselves can be deeply flawed. Matthew Warren is an MSc student at Balliol College, studying Neuroscience. Art by Nick Taylor.
Exercise Your Brain A real mental workout Everyone knows that exercise is good for your heart. Physical activity can help reduce your risk of heart disease and stroke, and reduce high blood pressure. These cardiovascular benefits have been cited for years but more recent research suggests that exercise is also good for your brain.
with executive control and long-term brain changes. In mice, exercise memory, respectively. More recently, promotes survival of neurons in the the hippocampus (a structure within hippocampus. It has been suggested the temporal cortex that is particularly that this may help improve learning important for and memory. It learning and is known that memory) has been “Regular physical Alzheimer’s, a shown to increase exercise can improve human disease in size in older a range of cognitive that causes IMPROVED COGNITION adults following a processes” memory Numerous studies have shown that year of moderate impairment, regular physical exercise can improve aerobic exercise is associated a range of cognitive processes, (walking). This finding is interesting with loss of hippocampal neurons, so including memory and executive because as people get older, the exercise later in life may help slow this control. Executive control is the hippocampus shrinks and the ability to decline. complex cognitive process that allows learn new things declines. The increase an individual to organize thoughts in hippocampal volume produced by As well as an increase in the number and activities, exercise may of neurons, there is also an increase prioritize tasks, protect against in the number of blood vessels in the manage time The hippocampus the natural loss hippocampus following exercise, which efficiently, and increases in size following of memory that help to deliver the nutrients that are make decisions a year of walking occurs as one required by the new cells. The blood by co-ordinating ages. vessel growth may be induced by an several mental exercise-related increase in molecules sub-processes to achieve a particular MRI can also be used to measure called growth factors (proteins that are goal. All these processes are impaired cerebral blood volume (CBV) – the key to the proliferation, specialisation, as people age, so it is promising that amount of blood in different brain and survival of cells). they can be improved with a simple regions. A study that investigated Measures of a specific type of growth intervention like exercise. CBV in individuals who had undergone factor, brain-derived neurotrophic a three-month aerobic exercise factor (BDNF), are increased following CHANGES IN THE BRAIN programme found that CBV increased exercise, in both humans and animals. The cognitive improvements following in areas of the hippocampus where new This discovery may eventually have exercise may be related to changes neurons form. This increase coincided broad health implications for diseases in brain structure. Using Magnetic with improvements in aerobic fitness associated with decreased BDNF, such Resonance Imaging (MRI), one and verbal learning. as Alzheimer’s and depression. experimental study in older adults showed that improvements in fitness WHAT CAUSES THESE Exercise is great, it can improve your are related to an increase in the volume BRAIN CHANGES? fitness and make you healthier, but of the prefrontal and temporal cortices. Animal studies may help explain the now it seems that it can also make you These brain regions are associated underlying cause of these structural smarter. While the mechanisms are not yet fully understood, the positive relationship between exercise and cognitive ability is definitely worth paying attention to. What better reason could you need for keeping active throughout your life? Nancy Rawlings is a postdoctoral researcher at the John Radcliffe Hospital. Art by Maria Demidova.
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Strictly Come Dancing... ...in the animal kingdom Natural Grace Whether it is busting out some ballroom for your college Dancesport team or putting your hands up Beyoncé-style on a night out, we all love a good dance. However, dance is not just for entertaining ourselves on the club floor. In fact, the very livelihood of many members of the animal kingdom relies on their ability to ‘bust a move’. Some organisms use dance as a means of communicating with their peers, attracting a mate, and even defending themselves from predators. Although slightly less diamanté-encrusted than Strictly, allow me to introduce the real stars of the dance floor…
ө
ө Hive
Vertical Honeycomb Wall
Directions Communicated by the Dance
Waggle Dance The humble honeybee exhibits one of the most common and yet most fascinating forms of dance. Known as the ‘waggle dance’, this repetitive figure of eight move is used by worker bees in order to communicate with other members of the hive, informing them about new sources of food or water. Like all good dances, the honeybee ‘waggle’ is nice and simple. Firstly, the worker-bee performs a straight ‘waggle run’, then turns to the right, circling back to its starting point,
before repeating the first step and then turning left to come back to the start, completing the figure of eight. Though straightforward, these movements allow honeybees to communicate vast amounts of information to one another. On the honeycomb wall, the bee dances at a specific angle relative to the vertical. This angle indicates the horizontal angle between the sun and the food source. For example, if the bee waggles at 60o to the right of the
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vertical, this tells the other bees that they should fly at 60o to the right of the sun to find a tasty treat. The duration of the dance is used to indicate the distance, a longer dance seeming to indicate a farther target. So, whenever a foraging honeybee discovers a fantastic new food source for the hive on its travels, it is able to return home and describe the location to its peers through a few simple steps, allowing the hive as a whole to benefit.
Crane Courtship If you were under the impression that romance in the animal kingdom is confined to Disney films, think again. A vast number of bird species all over the world use dance as a means of courtship, enabling them to find a suitable mate. But the members of one bird species in North America take it to the extreme in search of a soul mate. Found on the lakes of Oregon, USA, the Clark’s Grebe mates for life. In order to make sure they have the right guy, females put potential partners through their paces with a unique ritualized dance that the pair perform in synchrony. With a series of head-bobs, feather ruffles, and turns completed, the new couple celebrates their union in a grand finale, lifting their bodies out of the lake and waltzing across the water side by side. Not only does this dance ensure the female gains a committed partner with which to mate, but the love-birds use the dance as a way of reaffirming their union year upon year, providing a stable home (well, nest) in which to raise offspring.
Fig 1. Boy meets girl
Weasel War Dance Think you are the only one who pulls some strange shapes when overexcited on the dance floor? A slightly less elegant but equally intriguing behaviour can be found in members of the ferret and weasel family. The Weasel War Dance is a random, energetic dance routine performed by ferrets when particularly excited. The animals conduct a series of frenzied sideways and backwards hops with arched backs and frizzed tails when celebrating, for instance after the successful capture of a toy. Indeed the ferrets often get so caught up in the moment that they fall over or bump into objects. Though the behaviour has kept pet-owners amused for years, it has been suggested by researchers, such as Dr Carolyn King, that this behaviour in the domesticated ferret may have served a much greater purpose in the wild. The adrenaline-fuelled leaps and bounds of the animal may have acted as a way of confusing larger predators, enabling the ferrets to escape from a potentially sticky situation.
Fig 2. The pair dance, mirroring each other
Fig 3. The Grand Finale
From waggling bees to frenzied weasels, it is fair to say that the animal kingdom contains more than its fair share of dancing queens. However, as amazing as these routines might be to watch, perhaps the real beauty lies in the animals’ ability to use dance as a means of communication. From trying to impress a potential mate to informing the clan about a hotspot for food, such behaviour allows animals to interact and convey information to one another accurately yet without a dependence on the spoken word. Their exteriors may be lacking sequins, but when it comes to technique these animals definitely score a 10.0. Holly Youlden is a 2nd-year undergraduate at Keble College, studying Biological Sciences. Art by Inez Januszczak.
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NTE? OMG! If you squeeze something, it will shrink. If you heat something, it will expand. These two statements seem obvious, but in fact are not always true. Recently researchers have produced some striking examples of counterintuitive materials that contract on heating (negative thermal expansion, NTE) or expand in one direction when uniformly compressed (negative linear compressibility, NLC). When the atoms of a solid are given energy through heating, the bonds between them stretch and so the material expands. However, the atomic arrangement of a material can profoundly affect how it behaves when heated or compressed. Thus, by tuning the structure, unusual properties such as NTE or NLC can be produced. Zirconium tungstate, Zr(WO4)2, was the material that first ignited interest in NTE. Its unusual properties can be explained by a ‘skipping rope’ mechanism. The individual bonds (the rope) still lengthen when heated, but the additional energy causes a rotation of the bonds that makes them arc, like a skipping rope in motion. This brings the atoms at the end of the rope closer together, producing an overall contraction.
Zr(WO4)2
‘Skipping rope’ mechanism
Silver cobalt cyanide (Ag3CoCN6) actually shows both NTE and NLC. The ‘winerack’ structure of Ag3CoCN6 is key: each silver atom is bonded to two cyanide molecules either side of it, forming the ‘struts’. These ‘struts’ then attach to the cobalt atoms, which act as ‘joints’. The rigid struts mean that a contraction in one direction is accompanied by an equivalent expansion in the other. As the structure is extremely flexible, both expansion and contraction are colossal!
A winerack structure
Materials that shrink when others expand allow fabrication of composites that do not change shape with temperature or pressure. As one material expands, the other counterbalances it by contracting – this property is useful for high precision in extreme conditions, for example in satellite parts. More prosaically, zero thermal expansion materials would make for more robust dental fillings, although cyanide has an obvious drawback. The unintuitive properties of NTE and NLC materials demonstrate that science is full of surprises. Matthew Cliffe is a 1st-year DPhil student at Merton College, studying inorganic chemistry. Art by Nick Taylor.
Simultaneous contraction and expansion
Money for Old Lead
Buried deep underneath the Italian Alps lies CUORE, the Cryogenic Underground Observatory for Rare Events, built to investigate the strange properties of subatomic particles called neutrinos. CUORE differs from most physics labs however: while most modern experiments usually require cutting-edge materials, CUORE is utilising the properties of ancient Roman lead. CUORE is looking for an event predicted by a theory called ‘neutrinoless double beta decay’, which, if it exists, will confirm that the neutrino has the unusual characteristic of being its own anti-particle. Ordinary beta decay occurs when a neutron in the nucleus of an atom spontaneously transforms into a proton, an electron and an antineutrino. Theoretically, in neutrinoless double beta decay, two neutrons
decay simultaneously and the resulting anti-neutrinos annihilate each other. This annihliation could only occur if the neutrino it its own anti-particle.
These theoretical decays would be such extremely rare events that they would accumulate to generate only a tiny peak in the energy spectrum of the detected radiation. In order to distinguish the peak it is vital that ordinary background radiation is suppressed. The 1.5 km of Alpine rock that sits above the laboratory blocks most of the cosmic rays coming from space, but extra shielding is provided by a thick lead casing. Lead ore contains traces of radium-226, which decays very slowly to produce a constant supply of radioactive lead-210.
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Upon mining the ore and smelting the lead, the radium is discarded, cutting off the supply of radiation. The existing lead-210 impurity remains, but no more is produced. The impurity then decays with a half-life of 22 years, releasing radiation as it ages. This radioactivity makes newly formed lead unsuitable for shielding in very sensitive studies. The metal being used at CUORE was recovered from a shipwreck and is believed to have been smelted between 50 and 80 BC. Its radioactivity has decayed to a negligible fraction of the original level, making it an unlikely but ideal material for the experiment. Shielding anti-matter from cosmic radiation – just one more thing the Romans did for us. Jack Sennet is a 3rd-year undergraduate at Lincoln College, studying Physics.
Wood into Bone Growing a bone is not something we normally have to think about. Minor fractures usually heal themselves with remarkable ease when splinted up. However, problems arise with more severe fractures and degenerative diseases such as cancers, as these can require bone implants, and finding an effective substitute for real bone is far from easy. Currently most implants are made of titanium or ceramic composites, but there are issues with both. Titanium is not bioactive, meaning that it cannot interact with the body’s tissues, and ceramic composites, while acting as scaffolds for growing tissues by allowing capillaries to grow through them, are weaker than titanium implants. However, for those who feel compelled to go bull running in Pamplona, there is new hope. Scientists in Italy are researching a miracle bone substitute. The material, formed from Rattan wood, is superior to previous implants in many respects: as well as being spongy and
slightly flexible (unlike rigid titanium and ceramic composites), it is strong, durable, and does not need replacing. However, the main advantage of wood is that it contains an important carbon template that is similar to that which makes up real bone. This means it is easy for scientists to chemically transform Rattan wood into hydroxylapatite, known as ‘bone mineral’, which accounts for roughly 50% of real bone mass. The wooden bone can fuse with human bone and its porous properties allow nerves and blood capillaries to travel through it, fully integrating it into the skeleton. X-ray experiments in sheep have shown that particles from a sheep’s own bone actually migrate onto the wood-based bone. The implants show no signs of rejection or infection and after a few weeks the two become fully merged. Research into this bone substitute is being funded by the European Union and, while showing all the signs of a
revolutionary material, is a few years away from being cleared for human trials – so perhaps go easy on the extreme sports for now! David Wallis is a 2nd-year undergraduate at Exeter College, studying Chemistry. Art by Clementine McAteer.
A Nobel Endeavour In Copenhagen, April 1940, the Hungarian scientist George de Hevesy performed one of the most interesting chemical experiments of the war. Two esteemed German physicists, Max von Laue and James Franck, had committed the grievous crime of smuggling gold out of Germany. Fearing that their Nobel prize medals might fall into Nazi hands, they had sent them to the Bohr Institute in Copenhagen for safekeeping. But when the German army invaded Denmark, de Hevesy took charge of concealing the medals, which were incriminatingly engraved with the names of their owners. His first solution was to bury them, but Niels Bohr worried
that the medals would be discovered, so de Hevesy suggested something a little more audacious: he proposed to dissolve them. Gold is notoriously difficult to dissolve. Its inertness makes it, appropriately, a member of the family of ‘noble metals’. De Hevesy knew that only a powerful concoction would be up to the task, so he prepared a solution of Aqua Regia. This ‘royal water’ is a corrosive mixture of acids: one part nitric, three parts hydrochloric. Individually, the two acids have no effect on gold, but together they slowly dissolve it. Nitric acid prises gold atoms from the surface of the metal, which are then trapped in solution as AuCl4- (chloroaurate ions) by hydrochloric acid. This trickle of gold atoms into solution is not a rapid process. In fact de Hevesy was still dissolving the medals as the German
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army marched through the streets of Copenhagen. His perseverance paid off, however. He finally sealed the orange solution in a flask and left it on a high shelf in the laboratory. Here, the prize gold remained throughout the war, unnoticed by the Nazis who later occupied the Bohr Institute, who presumably mistook the jar’s contents for common chemicals like those all around it. Fortunately, the medals were not locked in solution forever: de Hevesy precipitated out the gold by neutralising the acid and returned the recovered raw material to the Nobel Committee. The medals were later recast and returned to their rightful owners, all thanks to the ingenuity of George de Hevesy. Charlie Hornsby is a 2nd-year undergraduate at Oriel College, studying Chemistry. Art by Ilse Lee.
Bang! talks to....
Robin Ince
We caught up with the writer, comedian and rationalist at the Wellcome Collection in London. ON THE SOURCE OF SCIENCE IN HIS SHOWS... The slow journey began when I was touring with Dave Gorman in the 90s – I had gone into a bookshop and picked up one of Richard Dawkins’ books, and a couple of other bits and pieces, which reminded me of how much I enjoyed science when I was younger. Then the real turning point was reading a book by James Randi, Psychic Investigator.
used to long walks, brought up in the countryside, all of those things. My dad of course, being of a different generation – normally they are, it’s very important – when he was a kid, he had a grass snake he would keep in his pocket when he went to church…
world, call that bird. Now let’s look at the bird. ”And that’s what I came back to, that ‘now let’s look at the bird’ phase.
ON BOOKS THAT INSPIRE HIM...
But any enjoyment of science went January is my Darwin month! Reading when I was about thirteen. I was Randal Keynes’ book Annie’s Box quite good at science, but then did which is based around the small box very badly in a Physics exam. It that belonged to Annie, Darwin’s was a disaster. daughter who died when she was It suddenly 10 years old, has just reignited my “The truth is, you know became a very passion for Darwin. For his language, almost nothing, I know I had gone off cold subject. I his interest in the world, his stand up. I realised think this is an humanity, his liberalism, all of these almost nothing” that what I was experience that things. For his love of his family. talking about was many people have increasingly banal, or actually of no had — that “science is like a subject”. The constant battle, I suppose, is interest to me. Then in the early part Well, science isn’t really a subject. To to remain interested. What I want of the 21st century, I started to think just say that there’s science, there’s people to get from anything I do that I should talk a bit about science, geography… Science is in everything, is a desire to find out more, to not originally from the sceptical point of and I think that’s what was lacking take my word for it. Reading Randal view, talking about psychic mediums, in my education. It was in my late Keynes’ book, or any book about homeopathy, iridology, those kinds 20s that memories of Carl Sagan’s Darwin, or any book about any of things. And Gillian McKeith, Cosmos, the joy of programmes like Victorian figure, one thing you will obviously! The Making of Mankind by Richard come across is the frequency of Leakey, all these things came back child death. This is something we I used to talk a lot more about to me, about how exciting this world are very lucky about now — we don’t politics, and I’ve kind of given up was, and that I had merely forgotten spend a lot of time standing around newspapers more recently because about it because I had been made the graves of our children. We have I realised that all they were doing bored, for a while. a life that is so was feeding me anger. There was a comfortable that “I think science, to me, lot of very vacant, empty rhetoric in I think in the first it has allowed us became the real way of the media, and I think science, to me, year of teaching to switch off, and became the real way of looking at the science we should not be amazed. looking at the world” world. I would try and look at things do ‘the walk where When we think of as much as possible from a scientific we wonder why’. Darwin arriving perspective, try and use evidence, Something that I quote a great deal in the Galapagos, imagine the shock! and then wonder why other people is the Horizon documentary with We would never have the same shock seemed to be getting to conclusions Richard Feynman where he talks when we see anything, because we which seemed so way off. about his dad taking him around, have television constantly delivering and his dad tells him about all the these images, making them banal ON SCIENCE IN different names that a bird has in almost. But for someone in the 19th CHILDHOOD... different countries. He goes through century to arrive on the Galapagos, all these names that the bird has and that’s an incredible thing – and I think I was brought up in a house with then he says, “When you know all we are in danger of forgetting how a lot of books. My dad would go those names, you know nothing, all incredible our existence is, all of the off photographing butterflies and you know are the names different things we have. hanging around badgers’ sets. I was people, in different parts of the
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ON ATTITUDES TO SCIENCE AND KNOWLEDGE... A friend of mine, who produces The Infinite Monkey Cage, says that she finds it ridiculous that my whole life is spent thinking, “I better learn about other things!” I think that one of the things that happens with adulthood is that to not know something is deemed to be a weakness. So many of us spend our time being ignorant — the certainty of ignorance — where we pretend we know everything. I think if you can keep that childish zeal, of going, “Look, I don’t know a lot of stuff!”… The truth is, you know almost nothing, I know almost nothing. Once you accept that, either you can go “I will go through life as an idiot, and be openly an idiot”, or “I’ll go through life and pretend I’m not an idiot, when in fact I don’t know anything that I’m talking about!”, or “I will try and remedy this situation”, which can never be remedied. I always get very annoyed with the sort of anti-science lobby that exists. I was reading about the republican presidential candidates, and the fact that to believe in evolution is somehow ‘liberal’…liberal!? There’s nothing about it being liberal, or fascistic, or whatever it is. It’s a collection of facts that has reached the point of being a scientific theory, which is constantly, with every bit of evidence that’s appeared in the last 150 years, being proved.
“I get very angry when people use the tools that have been created by human imagination and science to then send out their anti-science message” ON HIS FAVOURITE SCIENTIFIC FACT OF THE MOMENT... It’s not a scientific fact, but while reading about Darwin, I did enjoy finding out that when you started to miss your period because you were pregnant, the Victorian term was that you were “ceasing to be unwell”. I spent most of the autumn being fascinated by looking at deep sea creatures, and the ways that they’ve adapted. Whenever I look at a picture of a blobfish, that makes me very excited – and obviously I’m intrigued by the next set of results on the behaviour of these neutrinos… So, I couldn’t really nail it down to one thing I don’t think… I’m never good at single facts, it’s the big picture. There’s such a bombardment of information. I
I get angry when people use the tools that have been created by human imagination and science to then send out their anti-science message. I sometimes think, “Right okay, you can say all these things about why you think science is bad, but first we have to take away all the things that science has given you, so off your glasses come, away goes the recording device, and in fact away goes your life, because there was probably something you had as a child.”
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think on my deathbed I’ll be able to collate it, but at the moment, it’s just all these things that fire off… Actually this was one, it’s Louis Bunuel, he was a surrealist, there’s a line – “I am the sum of my errors and doubts, as well as my certainties.” We have to take all that in, you can’t just take in the things that you are right about; all of these contradictions that exist within us are fascinating things.
As well as writing, Robin presents The Infinite Monkey Cage, a podcast about rationalism and science with Brian Cox. His latest show, Happiness Through Science, is currently touring. Jack Binysh is a 3rd-year undergraduate at Lincoln College, studying Physics. Portrait by Anna Pouncey.
The Naked Mole Rat Looks aren’t everything After seeing an image of this incredible desert rat, the phrase ‘as ugly as a toad’ may lose its meaning. In fact, next to a Naked Mole Rat, a toad resembles a prince. However, as well as being one of the strangest looking animals on the planet, the Naked Mole Rat has an astonishing resilience to the environmental stresses that almost all organisms, including humans, succumb to. The question is: how? The Naked Mole Rat is native to parts of East Africa. It is almost totally blind and lives in underground desert burrows, which it digs with an impressive pair of front teeth. The organisation of the Naked Mole Rat society is similar to an insect society, with a single breeding queen and up to three king rats, supported by soldier and housekeeper rats. However, unlike an insect, the Naked Mole Rat is not a short-lived creature. While most rat species have a lifespan of approximately three years, the Naked Mole Rat may survive for thirty.
A LONG LIFE
Such a long lifespan for such a small animal seems unbelievable. It runs counter to the theory that smaller animals, which
have greater rates of metabolism, die cancers even when applying at younger ages due to an increased carcinogenic agents to the rodent’s rate of oxygen radical production. skin. One mechanism thought to Oxygen radicals are produced during account for this resilience is the respiration and their damaging rats’ extreme sensitivity to ‘contact effects have been linked to a range inhibition’. This process stops the of conditions, such as heart disease division of cancer cells when they are and neurodegeneration. Oddly packed closely together, and Naked enough, the Naked Mole Rat does Mole Rat exhibits it far more than suffer a lot of oxidative stress. other rodents. However, the rat seems more able to withstand this stress because of a A TOUGH LIFE rapid repair system – they have been Another remarkable characteristic of shown to quickly undo the damage the Naked Mole Rat is its immunity caused during to some types abnormal oxidative of pain. This onslaughts such is thought to “While most rat species as exposure to be caused by a have a lifespan of radiation. Strange lack of a certain approximately three years, characteristics neurotransmitter the Naked Mole Rat like these are of involved in the may survive for thirty” such interest to pain response. scientists that The rat feels last year the Naked Mole Rat joined no pain when exposed to acid or the handful of animals whose entire capsaicin – the active ingredient in genomes have been sequenced. chilli peppers. The hardiness of the Naked Mole Rat is also proved by One of the keys to the longevity the harsh environment it lives in. The of the Naked Mole Rat is thought air in the underground burrows has to be the use of an enzyme called an oxygen concentration twice as telomerase. This enzyme is low as atmospheric levels, and the found in all animals. It is carbon dioxide levels are over 100involved in repairing fold higher. The Naked Mole Rat has the DNA of our a range of adaptations to survive chromosomes, in these conditions. A specialised preventing gradual haemoglobin structure efficiently chromosomal transports oxygen, while adaptations shortening – a to the lungs and neurons allow adult process that is rats to endure extreme oxygen thought to be a cause deprivation for exceptionally long of ageing – and thus periods of time. halting the loss of important genetic The Naked Mole Rat provides great material. In most other promise in medicine, offering the animals, telomerase potential to eliminate post-surgical production is reduced pain and help in the fight against with age, but in the cancer. Proving that it’s not all about Naked Mole Rat it looks, there is absolutely no doubt remains stable. that the Naked Mole Rat is one of the most extraordinary creatures on The Naked Earth. Mole Rat is also incredibly Gareth Watson is a 1st-year resistant to undergraduate at St. John’s College, cancer; scientists studying Biochemistry. struggle to induce Art by Emily Motto.
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Bacterial Cities Urban living for single cells Unlike the cells that make up ourselves and almost every other visible piece of flora and fauna, a single bacterial cell is an entirely self-sufficient entity, capable of moving, respiring and reproducing by itself. Individual bacteria were first observed swimming in a suspension of dental plaque under a microscope by the Dutch scientist van Leeuwenhoek in 1683. This idea of the lone bacterium swimming solo through a liquid medium has since dominated bacteriology, mainly because it is straightforward to grow and observe these so-called planktonic bacteria in the lab. However, in a 1977 study of Alpine streams, a startling observation was made: very few bacteria were in the planktonic state. Instead, the majority were found in a slimy coating on the rocks, called a biofilm. This discovery was quickly confirmed in a wide variety of aquatic ecosystems. Far from choosing the nomadic lifestyle, most bacteria prefer a sedentary existence.
LIFE IN THE BIOFILM
Further studies show that a bacterium undergoes some dramatic behavioural changes upon attaching to a surface: it loses the unnecessary ability to swim, alters its metabolism greatly, and starts to secrete various substances to aid its surface attachment. Once one bacterium has settled, the biofilm grows by the processes of cell division and the recruitment of other strains. But the question remains: what do they have to gain from settling down and cohabiting in this way? In many respects, biofilms are like cities for their microscopic denizens, with similar advantages and disadvantages to those offered by human cities. Just as cities often have fortified defences, bacteria within biofilm communities are encased in a sticky concoction known as the extracellular polymeric substance (EPS). The EPS bestows dramatically improved resistance to antibiotics and detergents upon bacterial
communities. The inhabitants through crowded human populations, of biofilms are able to endure a the inhabitants of biofilms are concentration of antibiotics up to easy prey for phages, specialised one thousand times higher than their viruses that prey upon bacteria. planktonic equivalents. In hospital The cramped living arrangements environments, this can be deadly. The introduce a further limitation; whilst pathogen B. cepacia, which causes planktonic bacteria are free to devote fatal infections in the lungs of cystic a great deal of their resources to fibrosis sufferers, was discovered reproduction and growth, those in a in hospitals thriving in biofilms on biofilm are restricted by the increased bars of soap. The competition production of EPS for space and also helps bacterial “Biofilms are like resources. communities to cities for their anchor themselves microscopic denizens� Understanding firmly in rivers and the complex water pipes, where mechanisms that individuals would be rapidly swept enable bacteria to switch between away. nomadic and city-dwelling lifestyles is currently a major focus of research, LIVING TOGETHER with far-reaching consequences Just as there are many professions in industry and medicine. Biofilms in the city, bacteria exhibit a degree result in an annual loss of billions of specialisation within biofilms. For of dollars in the US alone due to example, it is thought that around corrosion and blockages in oil and gas 1000 distinct species of bacteria live pipelines. They are also responsible together in the biofilm that is dental for some of the most aggressive plaque, but only a few can feed on and dangerous human infections. It the nutrients available in saliva. remains a fascinating challenge to These few release various waste explore the processes underlying products, toxic to themselves, which the transformation of such minute other bacteria consume. Researchers single-celled organisms into such recently identified several pairs of astonishingly large and diverse tooth-colonising bacterial species bacterial cities. that were able to grow on salivacoated surfaces when combined, yet Ganriel Rosser is a final year DPhil failed to grow individually. student at St. Anne’s College, studying the swimming behaviour of bacteria. Living in a city has its drawbacks, Art by Inez Januszczak. too. Just as diseases spread rapidly
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Opinion:
Nuclear Power
David Thomas tells us why we should go nuclear An unfortunate side-effect of the recent economic crisis is that it has distracted us from our ongoing commitment to tackle global warming. Cutting greenhouse gas emissions remains one of the most pressing issues facing humanity, and yet they have continued to rise. According to most climate models, in order to avoid the most devastating effects of warming our emissions must peak by 2030. This poses an enormous challenge and will require all the tools at our disposal to limit emissions as soon as possible. We have two options for reducing our reliance on damaging fossil fuels: renewable resources and nuclear power. A large proportion of the public remains opposed to nuclear power and media campaigns have left many bewildered. But what do the facts tell us? The three main areas of concern over nuclear technology are plant safety, nuclear waste, and the economics of nuclear power.
Plant Safety Over 50 years the world’s nuclear reactors have accumulated over 14,000 years of operational reactor time. Of the 433 reactors, three in particular have suffered unfortunate incidents that grasped public attention:
and fire initially killed 31 people. The radiation released caused ongoing health and environmental concerns, though a major 2005 World Health Organisation report actually found the present death toll from Chernobyl to be fewer than 50 people.
Three Mile Island (1979): the reactor was severely damaged but radiation was contained and there were no adverse health or environmental consequences.
Fukushima (2011): Four old reactors were written off and the effects of a loss of coolant caused the containment to be breached and radiation released.
Chernobyl (1986): the destruction of the reactor by steam explosion
Since all of these reactors were built, nuclear plant designs have improved markedly.
Even with these rare incidents, nuclear power remains the form of energy that claims the fewest lives: 0.1 deaths per gigawatt year (GW y) of energy produced — a gigawatt year is equivalent to the amount of energy used by one million 1 kilowatt electric heaters if left on for a year. This makes it safer even than wind power with 0.2, though these numbers are tiny compared to oil, the most dangerous form of energy, which kills on average 4.1 people per GW y. We may also ask why public opinion on hydro-electricity did not waver following the Banqiao Dam disaster (1975), which killed an estimated 230,000 people.
Deaths per Gigawatt year
Deaths per gigawatt year for various forms of power. Data from The ExternE project.
Coal
Lignite
Peat
Oil
Gas
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Nuclear Biomass
Hydro
Wind
Power
Turbine
The stages of Nuclear Power
Waste
Storage
Economics There have been a number of studies examining the cost of nuclear power and many find it comparable to, or cheaper than, coal or gas.
backed up by another form of power and at present the only technology that can vary its electrical output to meet demand is gas, a fossil fuel.
Our only other low-carbon options are renewable resources. However in the UK, even at the theoretical maximum, with the entire country covered in wind turbines and every house covered with solar panels, we would still not meet our energy needs.
In contrast, nuclear power is not reliant on any other power source. Furthermore France, where the primary source of energy is nuclear power, has the cleanest air and the cheapest electricity in Europe, as well as some of the lowest carbon-footprint electricity in the world. Thus nuclear power is proving itself both economically and environmentally.
Furthermore, due to their intermittency, renewables have to be
In Conclusion It appears that the facts on nuclear power often contradict public perception, and failure to inform the public is leading to unfounded opposition to nuclear power. As we argue without consulting the evidence, we are not only delaying progress, but also increasing the use of fossil fuel power plants. People’s lack of knowledge of nuclear power could mean that we are missing out on one of the most efficient and
cost-effective ways of cutting our emissions. Nuclear power does not require us to develop new technology or seriously alter our daily routine. All we need is better communication to the public of the facts involved. David Thomas is a 4th-year undergraduate at Somerville College, studying Physics. Art by Charlotte Mason.
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Nuclear Waste The volume of high level nuclear waste produced is tiny. The ash produced by 10 1GW coal power stations in the UK over a year is about 40 litres per person. In comparison, Britain’s 10 1GW nuclear power stations produce 0.025 litres of highlevel waste per person per year. Moreover, processing nuclear waste is not as dangerous as is often imagined. People who work with nuclear waste every day in reprocessing facilities get a lower annual dose of radiation than airhostesses, and a processed canister of nuclear waste emits less radiation than a block of granite. Furthermore, the final disposal of these canisters is not an unresolved concern. Nuclear waste decays back to the same radioactivity as the original ore from which it was mined after approximately 1000 years, and there is no practical reason why nuclear waste cannot be stored in a deep geological site; Finland has built just such a depository. The only barrier stopping the UK and other governments from following suit is political will.
Find the answers across this issue!
Puzzle 1
2
3
4 5 7
9
6
ACROSS 1. Naked and painless (7, 2) 5. Struts and joints in structure (8) 7. Last smelters of CUORE’s metal (6) 11. Dissolve gold in this (10, 2) 12. Waggle feature indicates distance (8) 13. Godël’s troubling theorems (14) 15. TMS depends on this technology (16) 16. Sir David’s were too big for television (5)
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DOWN 2. Popular pre-print paper archive (5) 3. Bone mineral (16) 4. Robin Ince’s Darwin month (7) 6. Wegner’s “trick of the mind” (9) 8. Biofilms’s extracellular polymeric (9) 9. Loss of hippocampal neurons, cause (10) 10. “A” is often this colour (3) 14. Monty Hall’s magazine fame (6)
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4-Year PhD Programme in Theory and Simulation of Materials Do you relish the challenge of understanding mathematically complex physical phenomena? Do you want to apply your talent for theory to address some of the most significant issues faced by modern society? If the answers to these questions are YES! then a PhD in the Centre for Doctoral Training on Theory and Simulation of Materials at Imperial College London could be for you. It’s hard to think of a modern technology that is not completely dependent on materials: energy production, telecommunications, aerospace, information technology, and pretty much everything else we take for granted in modern life. Our ability to understand the fundamentals of materials behaviour and to use theory and simulation to guide the selection of materials, to optimize design and performance, and to predict and avoid failure are crucial to these technologies. We have funding for up to ten 4-year PhD studentships. Applicants should have, or expect to achieve, a first class Bachelor or Master degree in the physical sciences or engineering. For more information and how to apply, visit
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VACANCIES AVAILABLE FOR SCIENCE, MATHS, IT & DT FOR 2012
t ‘Young people don’ fail in education: education fails them and that’s not acceptable’ Kafilat Agboola, taught Science. now Faculty Head of Science
Applications closing soon
For further information contact Maria Donovan mdonovan@teachfirst.org.uk
www.teachfirst.org.uk Teach First is a registered charity, no:1098294
* Sutton Trust, 2010