Hippocampus MRI

We all like to think we can rely upon our memories; that our brain functions in a black and white fashion of either remembering or forgetting. We depend on them functioning in this manner to make our way in everyday life. However, science has consistently shown that our memories can be distorted and changed without our awareness. Be it adverts, political campaigns or the opinions of our friends, our recollections are subject to being ‘rewritten’ by the views of others – a phenomenon dubbed ’memory conformity’.

On a public level, we might outwardly conform to what others say but inwardly remain certain of our own memory of events – perhaps for ease of social compatibility or a fear of being rejected. And sometimes that misremembering will become permanent, even when the social influence is long gone.

A new study shows how this occurs through actual changes in brain activity, and that different cognitive processes are involved when we just outwardly agree with other people’s recollections.

Researchers at the Weizmann Institute of Science in Israel and the Wellcome Trust Centre for Neuroimaging in London, presented volunteer test subjects with an eyewitness-style documentary. Three days later, the participants answered a series of memory-based questions about the documentary.

Four days after that, they returned to the lab and underwent brain scans using fMRI (functional magnetic resonance imaging). At this point, the researchers showed them a set of answers (which were actually all incorrect), telling them these were from four fellow participants. Remarkably, the subjects conformed to these answers in 68 per cent of trials – even though they had given correct answers in a previous test.

A week later, the participants underwent further fMRI scans. This time the researchers told them that what they’d showed them previously were actually random answers. Yet, when the subjects took the memory test again, they continued to give the same wrong answers to 40 per cent of the questions. This suggests that their memory of the documentary had been altered by what others said they had seen.

The brain scans from the final test revealed differences in brain activity when participants continued to quote the wrong answers, compared with when they reverted to their original memory of events. When they continued with the wrong answers, they showed greater activity in the left part of the amygdala – the brain area associated with social and emotional processes.

The socially-induced memory changes were associated with heightened connectivity between the amygdala and the hippocampus (the ‘memory region’ of the brain). The researchers say this activity may represent a process of ‘reconsolidating’ the new representation of events in their memory.

All this provides some evidence of how privately conforming to what others say is accompanied by actual changes to our memories, highlighting the role of social influence in modulating memory. And if all this sounds a bit too much like brainwashing, well, it’s not all bad. Other research has suggested that social learning in this way is often more efficient and more accurate than trying to remember everything by ourselves. So, on the flipside, relying on others’ memories is the brain’s way of saving us a bit of effort.

Reference:

Emma James

Emma James is a summer intern at the Wellcome Trust.

Image credit: Laura B. Dahl on Flickr

Lynn Boulanger, an occupational therapy assistant and certified hand therapist, uses mirror therapy to help address phantom pain for Marine Cpl. Anthony McDaniel.

V S Ramachandran, the Director of the Centre for Brain and Cognition at the University of California, has in the past been described as the ”‘Marco Polo of neuroscience” and a man who has “done for the brain what Galileo did for the Cosmos”. His key approach involves studying brain abnormalities to reveal more about the workings of the brain as, he explained, a small change can result in a highly selective loss of function. Ramachandran argues that looking at the correlations between physical and functional deficits should help us to understand the brain, in the same way that it has helped us to understand the rest of the body.

Ramachandran was in our building to record a special lecture, part of the Exchanges at the Frontier series Wellcome Collection hosts in collaboration with the BBC World Service. Among other topics, he spoke of the research he is perhaps most known for: phantom limbs.

We heard about ‘Victor’, a patient who had lost his left arm forearm in an attempt to illegally cross the Mexican border. Like 98 per cent of amputees, Victor could vividly feel the presence of his absent arm. Two thirds of ‘phantom limb’ sufferers also experience intense pain, as if the limb is clenched and tight. Ramachandran discovered that this pain could be resolved in many patients by using a mirror to superimpose the reflection of the real limb onto the phantom location. He found that movement of the real limb can ‘trick’ the brain into relieving the tension from the phantom limb. This method has since been used to successfully remove pain and restore mobility in other conditions as well, such as reflexive dystrophy, and potentially even during the first few months of having a stroke – although this is still in early stages of research. Interestingly, Ramachandran said, the phenomenon is beyond the purely psychological – research has found that the physical swelling of painful limbs is also reduced following mirror treatment.

Vilayanur S Ramachandran

Mirror treatment may demonstrate a function of mirror neurons – frontal lobe cells that become activated both when the individual carries out motor tasks and when they see that task being carried out by someone else. The precise role of mirror neurons is yet unknown, and forms the basis of Ramachandran’s most recent work. According to Ramachandran, these neurons may have been the root of human culture, providing a system by which we could watch and learn new skills. Outlining what is known as a ‘shattered mirror theory of autism’, he theorised how mirror neuron deficits might also account for many of the defining features of autism, such as failing to engage with and understand others. However, it’s worth noting that the theory remains controversial, with a range of conflicting evidence.

Besides phantom limbs and autism, Ramachandran also discussed his ideas about synaesthesia and its prevalence in society. The condition sees that the stimulus of one sense can produce sensations in another, leading to ‘tasting words’ or ‘smelling sounds’ (for more, see our recent interview with a synesthete). It is thought to have a genetic basis, where excess connections in the brain are not completely pruned away in early development. This leaves accidental cross-wiring between particular adjacent regions – for example, between the areas recognising words and colour in the brain, leading to grapheme-colour synaesthesia. Ramachandran believes that the synaesthesia gene might have some ‘hidden agenda’ that can explain its prevalence among society, and has noted that the condition is eight times more common in artists, poets and other creative people. He suggests that the excess connections aid synesthete in linking seemingly unrelated concepts in creative ways, making them skilled in the creative arts.

All the topics Ramachandran touched on were truly fascinating, exploring conditions and treatments almost unimaginable to those of us who haven’t experienced them. The full lecture will be broadcast on the BBC World Service in November (watch the BBC’s website, where you can also listen to lectures from the previous two seasons) and is well worth listening to. With so many interesting ideas, it was clear how has earned his status as one of the world’s most influential scientists.

Emma James

Emma James is a summer intern at the Wellcome Trust.

Find out more about Exchanges at the Frontier on the Wellcome Collection website.

Image credits:
Mirror therapy: U.S. Navy photo by Mass Communication Specialist Seaman Joseph A. Boomhower
Ramachandran: David Shankbone on Flickr.

X-ray image of a bag.

The Royal Society’s annual Summer Science Exhibition gives the public a chance to meet the scientists behind some of the most recent research advances and experience first-hand the type of work they do. From quantum mechanics and musical graphs to rotting fish and trauma surgery, this year’s exhibition had a huge variety of science to interest anyone and everyone. Emma James went along to explore.

The first thing that struck me when walking into the exhibition was people, and lots of them. As I wondered around the 22 stands to try and find somewhere to start, I saw crowds of young and old alike, interacting with the various tasks and quizzing the exhibitionists. It was great to see so many people engaged in science, although the small impatient child in me was just beginning to wonder how long it would take to have a turn at anything…

The first opening I spotted fortuitously turned out to be the Wellcome Trust-funded one. ‘Guns, knives and bombs: spotting weapons in baggage X-rays’ had researchers from the School of Psychology at Southampton University explaining how airport security works. As a psychology student, it raised my curiosity: how does psychology help spot terrorists?

The answer lies in visual perception. The Southampton research looks at how we search for and identify objects using our eyes and the factors affecting this process. I tried my hand at a simple search task on the laptops. This showed me the effect of ‘dual target cost’ – my reaction time almost doubled when I was searching for one of two targets, as opposed to focusing on whether a single target was present.

The University of Southampton School of Psychology stand at the Royal Society Summer Science Exhibition 2011.

Moving on to the next part of the stand, I learnt how this can affect airport security. As I tried to identify guns and bombs in real luggage X-rays – which show up as blue and orange according to their atomic density – a clever little machine tracked my eye movements to see where I was looking. The team’s research has shown that it is better to focus on one type of target at a time, as searching for more can lead observers to spend more time looking at irrelevant objects and not enough at the objects that matter. Having let a bomb go past unnoticed, I was inclined to agree.

The final part of the exhibit demonstrated a direction for their future research – would it be beneficial to introduce 3D imaging into luggage scanning? A gun, for example, might not be identified when viewed at certain angles, but might be noticed if it could be seen protruding towards the observer. If 3D imaging significantly increases accuracy, this could direct the training methods used for airport security and maybe even the advancements of X-ray technology.

Having missed two guns in one task and a bomb in another, I concluded that I should never work in airport security. As for the rest of the exhibition, I learnt how scientists are using nanotechnology to make fuel from the sun’s energy, what the world would look like with bionic vision, and how graphene – the thinnest material known to man – can be made by peeling apart the layers of graphite. The latter even earned me my very own Nobel Prize (albeit a chocolate one).

Nobel-prize medal chocolate

Emma James

Emma James is a summer intern at the Wellcome Trust.

Find out more about Exchanges at the Frontier on the Wellcome Collection website.

Eleanor Maguire

To mark the 75th anniversary of the death of Henry Wellcome and the founding of the Wellcome Trust, we are publishing a series of 14 features on people who have been significant in the Trust’s history. In our eleventh piece, ‘New Scientist’ editor Roger Highfield looks at Eleanor Maguire, Professor of Cognitive Neuroscience at the Wellcome Trust Centre for Neuroimaging at UCL.

“If any one faculty of our nature may be called more wonderful than the rest, I do think it is memory. There seems something more speakingly incomprehensible in the powers, the failures, the inequalities of memory, than in any other of our intelligences. The memory is sometimes so retentive, so serviceable, so obedient; at others, so bewildered and so weak; and at others again, so tyrannic, so beyond control! We are, to be sure, a miracle every way; but our powers of recollecting and of forgetting do seem peculiarly past finding out.” – Jane Austen, ‘Mansfield Park’

The way that our recollections shape who we are and the way we think has long been explored in literature and popular culture, from the writings of Marcel Proust and Philip K Dick to films such as ‘Strange Days’, ‘Memento’ and ‘Eternal Sunshine of the Spotless Mind’. But when Eleanor Maguire first became interested in the subject, her motivation to put memory on a scientific basis was more personal. “I am absolutely appalling at finding my way around,” she confesses. “I wondered: ‘How are some people so good and I am so terrible?’”

She started out her quest to understand memory while working with patients for a doctorate at University College Dublin. Today she is still dedicated to the quest, as a Wellcome Trust Senior Research Fellow and Professor of Cognitive Neuroscience at the Wellcome Trust Centre for Neuroimaging at University College London, where she heads the Memory and Space research laboratory.

Maguire wanted to explore how our experiences, both big and humdrum, forge and sunder the vast network of connections between cells in a human brain: it is these connections that are central to who we are. And the spur that drives her on to understand them remains the same now as it was when she began her great scientific adventure in Dublin: “I still get lost in the Centre for Neuroimaging and I have been working here for 15 years.”

She and her dedicated team of half a dozen colleagues are studying these gossamer threads of recollection with brain scanners, notably magnetic resonance imaging (MRI) techniques. Some are tuned to reveal the extraordinary structural complexity of the brain (structural MRI), others to the tiny changes in blood flow that accompany thought (functional MRI, or fMRI).

But central to her work is the field of neuropsychology, working with people who have some kind of memory impairment such as amnesia. “fMRI can tell you which brain areas are involved in memory but you are never sure which ones are really necessary. That is where the study of patients comes in.”

She is most fascinated by one region located deep in the brain called the hippocampus, so named because the Venetian anatomist Julius Caesar Aranzi (in 1587) initially likened it to a seahorse (‘hippocampus’ in Latin). This is known to be a memory centre – and is damaged in people with amnesia – but Maguire’s investigations suggest that its role is more subtle and interesting.

She believes (as do others) that it provides a kind of spatial scaffold for memories, one that is essential if we are to make sense of our experiences. “One patient with amnesia tried to articulate what it was like never being able to remember. He said: ‘It’s like having a load of clothes I need to hang up in a wardrobe but there’s nothing to hang them on, so they all fall on the floor in a mess’.”

In the long run, the hope is that Maguire’s research will help us understand how memories can be affected by age and shredded by dementia and developmental disorders. With that understanding may, of course, come new tests and treatments. “We are all about helping patients, ultimately. But we can’t come up with new kinds of rehabilitation until we understand precisely how memory works.”

Learning ‘the Knowledge’

Her first big advance came in 2000, in a study that would generate headlines worldwide, capture the public imagination and even win her a share of the highly coveted Ig Nobel Prize, a parody of the Nobel Prizes that is handed out each year for achievements that “first make people laugh, and then make them think”. Even today, she still gets hundreds of media inquiries every year to find out more about this particular piece of research.

In her first experiment for this study she scanned the brains of 16 London black-cab drivers who had spent an average of three or four years learning ‘the Knowledge’ – the entire layout of the 25 000 streets in London. What she discovered challenged the prevailing view of the brain as at best static and at worst forever shedding cells as a result of knocks, hangovers and ageing. In fact, the brain behaves like a muscle: use brain regions and they grow.

What was remarkable was that she found the taxi drivers had a larger hippocampus than control subjects, particularly on the right side. The longer they had been on the job, the larger their hippocampus. These findings seem to indicate that the hippocampus plays an important role in storing spatial memories.

She moved on to study London bus drivers. It turns out that bus drivers do not have the same enlarged area, even though they had been carefully selected to have had similar experience on the road. This suggests that general skill at driving is not related to hippocampus size, and that the difference in size is indeed linked to knowledge of the layout of the city’s streets built up by taxi drivers over many years, since bus drivers use much more restricted routes.

To make absolutely sure that the hippocampus is indeed central to navigation, Maguire and colleagues went on to follow the progress of trainee taxi drivers. As they became more experienced, she could peek at what was happening to their hippocampi. It turns out that only half pass their final test of the Knowledge. In a satisfying conclusion to her effort to pin down the role of the hippocampus, she found the successful drivers were the ones that showed the greatest alteration of the hippocampus. Essentially, “experience can change the brain,” she says. There was a fascinating corollary to this: did the half who failed to qualify lack a hippocampus that was sufficiently malleable? “Perhaps there is a genetic disposition. We will have to look into this.”

Studying the way the drivers used this enlarged area of the hippocampus was more difficult. Because an MRI scanner is a room-sized affair, where the subject lies inside a giant magnet, there’s no way to carry out these studies in the back of a cab. Maguire and her team devised a series of virtual-reality tasks that the subject can carry out, without physically moving, on a screen inside a scanner. Developing these virtual-reality environments was not easy, even though they adapted versions of commercially available video games. “We had to take out all the shooting and monsters so that we were left with the basic environment.”

Using the PlayStation 2 video game ‘The Getaway’, which is set in central London, she and her researchers could examine how taxi drivers use their hippocampi and other brain areas when they navigate around the city. They found that the hippocampus is most active when the drivers first think about their route and plan ahead. By contrast, activity in a diverse network of other brain areas changes as they encounter roadblocks, spot expected landmarks, look at the view and worry about the thoughts of their customers and other drivers.

Inside the hippocampus and neighbouring brain areas, it seems that three basic types of cell are involved in spatial maps. These are called place cells, head direction cells and grid cells. Place cells map out our location, lighting up to say ‘you are here’ when we pass a specific place; there are thought to be hundreds of thousands of these cells in the hippocampus, each preferring a slightly different geographical place. Head direction cells act like a compass, telling us which way we are facing. And grid cells tell us how far we have travelled, akin to how we use latitude and longitude for navigation.

The navigational knowledge of taxi drivers shows up in their brain scans.

Maguire’s team has done further work on black-cab drivers to see whether the hippocampus will shrink back to its normal shape if they stop using it ‘professionally’. After the difficult job of tracking down retired cabbies (“they are so hard to find,” she explains, “because they never seem to retire”) she found that, yes, this was indeed the case.

To complement this finding, she studied a taxi driver of 40 years whose hippocampus had been damaged by a viral infection, leading to amnesia. While he was able to navigate using major or ‘A’ roads, he was no longer able to navigate through the winding, minor streets of the capital. “That shows that the hippocampus is necessary for fine detailed spatial representation of the city.”

Do similar changes accompany other feats of exceptional memory? To find out, Maguire and colleagues studied participants in the World Memory Championships, which take place every year in London. “People entering the World Memory Championships can do amazing things,” she explains. “They can memorise the order of cards in deck after deck of cards, for example. One memory champion passed time waiting in reception prior to his scan by memorising pages from the phone book – pretty well, too; I tested him on it.”

What was fascinating was that she could find no structural changes of the kind seen in the taxi drivers. Like the bus drivers, it seems that their memory feats did not place the same demands on the hippocampus. This emerged when she asked them what strategies they used. Nine out of ten of them had used the same strategy: an ancient Greek method, called the method of loci. “It’s based on navigation: they imagine going down a street they know well, place items at certain positions along the street, then mentally retrace their route to find the items.”

Although this strategy uses spatial memory to boost performance, the amount of large-scale space memorised is small, possibly accounting for the lack of structural changes in the hippocampus. “Their brain doesn’t have to change to accommodate a large map of London in their heads as it does for the cab drivers; the memory champions just need to memorise a couple of routes in detail.”

She could also ask a more basic question. Does the hippocampus store a ‘virtual map’ of the physical world or is it recalling relationships between objects in a more generic way? To test this, the team used fMRI to reveal which parts of participants’ brains were active as they visualised the spatial route between their friends’ houses compared with the social connections between the friends themselves. The tasks activated separate brain networks: the hippocampus is active when people visualise navigating to different locations but not when they navigate social networks of friends. What is satisfying is that the conclusion of this work complements the findings of studies of rats: the hippocampus is central to navigation.

Remembering our past

In recent years, Maguire has focused more on the second critical role of the hippocampus, in laying down autobiographical (episodic) memories of our past experiences. Here, people with anterograde amnesia have played a central role in her studies.

These people live permanently in the present. Their speech and intellect tends to remain intact, because remembering facts and general knowledge is not dependent on the hippocampus. However, their experience of the world is frozen in time: they cannot remember anything that occurs after their brain damage took place. Maguire says: “If they do a couple of hours of tests with me, for example, and I leave the room for ten minutes and come back, they can’t remember anything about me or what they had been doing. They can’t live alone because they can’t remember if they turned the gas off or paid their bills. Sometimes, which is very sad, if a spouse dies, they can’t remember their loved one is now gone.”

In the healthy brain, many regions are involved in supporting personal, autobiographical memories, because these are coloured with emotions and depend on the spatial, temporal and social context. To understand how the brain stores and recalls this form of memory, it is important to evoke the ‘whole’ memory during studies. One way of doing this is to project a photo of a party or wedding from a family album onto the screen, prompting the participant to recall and re-create this particular event in their past while their brain is being scanned.

In this way, Maguire and her team have investigated the episodic memories of everyday events, such as seeing someone posting a letter or preparing to ride a bike. To explore how such memories are recorded, her team showed ten volunteers three short films and asked them to memorise what they saw. The films were basic, sharing a number of similar features: all included a woman carrying out an everyday task in a typical urban street, and each film was the same length, seven seconds long. For example, one film showed a woman sipping coffee from a paper cup in the street before discarding the cup in a litter bin; another film showed another woman posting a letter.

The volunteers were then asked to recall each of the films in turn while inside an fMRI scanner. A computer program then studied the patterns and had to identify which film the volunteer was recalling purely by looking at the pattern of their brain activity. Remarkably, it was possible to tell which film they were recalling.

Although a network of brain areas support memory, the computer program performed best when analysing activity in the hippocampus itself, suggesting that this is the most important region for representing episodic memories. In particular, three areas of the hippocampus – the rear right, front left and front right areas – seemed to be involved consistently across all participants.

This work suggests that our memories are encoded within the brain in a predictable way. While earlier fMRI work has shown the typical brain areas involved, this study, after averaging the activity in many heads, showed the precise circuits used to lay down a recollection of one particular memory trace in an individual’s brain, down to a resolution of just over one cubic millimetre – revealing much more detailed information about the hippocampus at work. “That is very exciting because it means we can look at specific memory traces,” says Maguire.

Now it is possible to investigate precisely which brain areas hold a given memory, how this trace varies with time and what happens as a result of disease or injury. But, of course, there are even more speculative implications. Does this mean that we will one day be able to use a scanner to read a mind?

Maguire emphasises that her participants were tasked with recalling one of three short films that they had previously viewed, so the researchers were already aware of the nature of what it was they were thinking about, just not the identity. “There are ethical issues but we did do the study with the cooperation of the patients and, although arguably a form of mind reading, it does take place under very controlled circumstances.”

While confirming the key role of the hippocampus in recalling past events, Maguire and colleagues went on to make a fascinating discovery when she asked people with amnesia to describe imaginary experiences. She and her team asked the patients to imagine and then describe in detail situations in commonplace settings, such as a beach, pub and forest, as well as potentially plausible future events such as a Christmas party. The patients’ ability to construct future and fictitious events was also severely impaired. “The role played by the hippocampus in processing memory was far broader than merely reliving past experiences,” she says. “It also seems to support the ability to imagine any kind of experience including possible future events. That is why, in this sense, people with damage to the hippocampus are forced to live in the present.”

“Furthermore, the patients reported that they were unable to visualise the whole experience in their mind’s eye, seeing instead just a collection of separate images. We believe this suggests a common mechanism that might underpin both recalling real memories and how we visualise imaginary and future experiences, with the hippocampus providing the spatial backdrop or context into which the details of our experiences are bound,” she explains. The work closes the loop with her studies on spatial navigation, and other animal studies in the literature, showing that space may be the key to understanding the function of the hippocampus and its role in memory.

Maguire has come a long way since she first thought about the neuroscience of memory in Dublin. She has won much recognition of her extraordinary contribution: the Cognitive Neuroscience Society Young Investigator Award; two Wellcome Trust Senior Research Fellowships; the Royal Society Rosalind Franklin Award; and the Feldberg Foundation Prize, made for outstanding contributions to science.

But her quest is far from over. Huge challenges remain if she is to confirm that the hippocampus indeed plays a central role in providing the spatial context for our experiences and helping us to think about the future. “I believe that it is there to support coherent scenes. It is providing a spatial backdrop, or canvas, on which we play out the recall of memories, plan a route or simulate what will happen to us in the future. But that is still quite controversial and we need to link a lack of spatial representation directly to amnesia.”

She is also keen to apply her work in novel treatments for memory disorders. The good news is that the study of taxi drivers suggests that it is possible to train a hippocampus. For people suffering from hippocampal damage, and associated difficulties with memory, the question of whether the brain can mend itself, and memory be recovered, is a pressing one.

“Findings like those from our study of London cab drivers show that structural changes can occur in healthy human brains. Perhaps in the future we could use that kind of understanding to help people with hippocampal damage.” But, of course, many other circuits are involved in memory. “When we use fMRI, other brain regions are engaged also. We still don’t know a great deal about what they are doing. Until we do, it won’t be possible to design a memory rehabilitation programme with confidence.”

Today, Maguire is gratified that her work has gone beyond the confines of the international conference circuit and academic journals. More than a decade after she started her pioneering research, she sometimes finds herself in the back of a London taxi. “Cabbies often tell me about my work, not realising who I am. It is extraordinary to hear them talk about the hippocampus.”

Thanks to Maguire’s pioneering work on memory, many London cab drivers now possess a little of neuroscience’s equivalent of the Knowledge. For years to come, her work will be remembered for how it changed the way we think about memory.

Find out more about activities marking the Wellcome Trust’s 75th anniversary, including links to other features as they are published.

Roger Highfield is the Editor of ‘New Scientist’. For two decades he was the science editor of the ‘Daily Telegraph’ and he still contributes a column to the science page of the newspaper. He has written or coauthored several books. The latest, written with Martin Nowak, is ‘SuperCooperators: The mathematics of evolution, altruism and human behaviour (Or, Why we need each other to succeed)’.

Image credits: Wellcome Images

Further reading

Chadwick MJ et al. Decoding individual episodic memory traces in the human hippocampus. Curr Biol 2010;20:544-7.

Hassabis D et al. Patients with hippocampal amnesia cannot imagine new experiences. Proc Natl Acad Sci USA 2007;104:1726-31.

Woollett K et al. Talent in the taxi: a model system for exploring expertise. Philos Trans R Soc Lond B Biol Sci 2009;364:1407-16.

A violin made by Carlo Antonio Testore

Language is a difficult thing to learn – think how many hours a child puts in listening and practicing before they’re able to hold a conversation. Several areas of the brain show higher levels of activation in response to spoken language than they do to other complex sounds.

Much debated in the field of neuroscience is whether the neurons found in these areas of the brain are innately predisposed to learning speech from birth or whether they’re just particularly responsive to complex stimuli.

To answer this question Dr Fred Dick, from the Birkbeck­–UCL Centre for Neuroimaging, and colleagues used fMRI scanning to map the brains of female actors and musicians, looking particularly at the parts of their brains that responded to speech or music.

Like learning language, becoming an expert musician takes years of practice, for many hours a day. Concert level performers often start at a very young age, similar to language learning.

Dick tested the two groups by playing them short excerpts – either dramatic monologues from a variety of plays or solo violin pieces (the balcony scene from Romeo and Juliet or Mozart’s fifth Violin Concerto, for example). Some samples would be familiar to each participant, others not.

The results showed increased activity in a subset of the ‘expertise’ regions of the brain when the actors listened to familiar speech and when the musicians listened to familiar music. But surprisingly, unfamiliar audio produced a similar pattern of brain activity.

That both music and speech activated similar neural regions suggests that it is experience, not innate ability, driving brain development. Learning a complex skill takes time, and certain parts of the brain appear more ‘plastic’ and able to develop over time.

The reasons that unfamiliar music or speech activates the same regions as the familiar are unclear. Dick suggests that this may be due to the expertise of the musicians and actors. Expert performers may have a deeper understanding of their subject matter and have a greater ability to predict the patterns that will occur in the unfamiliar sounds.

Benjamin Thompson

• Dick F, Lee HL, Nusbaum H, & Price CJ (2011). Auditory-motor expertise alters “speech selectivity” in professional musicians and actors. Cerebral cortex (New York, N.Y. : 1991), 21 (4), 938-48 PMID: 20829245

Image credit: pellaea on flickr

Dr Michael Eddleston

Congratulations to two of our researchers who have recently been awarded prizes for their work.

Michael Eddleston from the University of Edinburgh has been awarded a Lister Research Prize for his work on preventing suicide in Sri Lanka. Dr Eddleston’s work has shown that suicide rates can be rapidly and drastically reduced by banning the most toxic pesticides in low-income countries, without affecting agricultural output or input costs.

The Lister Research Prizes, of which three are awarded each year, provide young scientists with £200 000 of funding over a five-year period to develop their potential as research scientists.

Dr Emily Holmes

Following on from her recent award from the British Psychological Society, Emily Holmes, a Wellcome Trust Intermediate Clinical Fellow from the University of Oxford, has been awarded the Comenius Early Career Psychologist Award by the European Federation of Psychologists’ Associations. Dr Holmes was nominated for the award in recognition of her work on trauma, cognitive and emotional processing and memory.

The Comenius Award is given to a young psychologist from Europe who has made an original contribution to psychology as a science and profession. In its decision, the awarding committee noted that Dr Holmes “has made major advances in the field of memory and trauma using typically the trauma film paradigm. Her distinctive theoretical contribution has been to link the limited field of imagery and cognitive psychology to the rich clinical and experiential material of emotional memories following trauma”.

James Wannerton, who has a form of synaesthesia

Who are you?
I work in IT and have lexical-guastatory synaethesia, an extra connection between two areas of my brain. It means that whenever I hear, see or read something, I get a specific taste. Even though I’m not eating something – and I know I’m not – it seems pretty real to me.

Unless I spoke about it, there’s no way you’d know I was a synaesthete. I did bring it up a couple of times at school and home but it never went anywhere. My ex-girlfriend didn’t know for years and years. My parents found out because I was on an episode of Horizon. They were quite put out about it at the time and still are now.

When did you first realise you had this ability?
You have to bear in mind that this is perfectly normal for me, so it’s a bit like asking when was the first time you smelt something and what did it smell like – you can’t remember. I can certainly remember picking up tastes when I was at school, around the age of four and a half. I have very strong memories of sitting in assemblies. We were read the Lord’s prayer every morning: it had a taste of very thin crispy bacon.

Talking about it now, can you taste it?
Yeah. It’s quite strong as well.

Can you describe synaethesia?
It’s not an extra sense, but it does give me an extra perception. It’s like getting an eye-dropper of taste dripped on my tongue. I get a taste, temperature and texture. One of the ways I stop this affecting my concentration on a day-to-day basis is to eat strong-tasting sweets like Wine Gums, and drinking coffee.

Do you ever synaesthetically taste something you’ve never eaten before?
It can be difficult to articulate a particular sensation and compare it to a foodstuff. These things are specific and very, very complex. When I’ve taken part in research, I could write maybe half a page of A4 on a particular word’s effects.

Ever since I was young, I had a taste for the word ‘expect’ and I could never quite put my finger on what it was. One day, I bought a packet of Marmite-flavoured crisps. When I had one, it clicked – that’s the taste of “expect”! If I had to describe it I’d say it’s a bit tangy, slightly thick but crunchy.

I get lots of metallic tastes that I can’t describe, other than saying it’s smooth or rough. The name David gives me a very strong taste of cloth, a bit like sucking on a sleeve.

How has it affected your life?
When I was younger, I used to choose friends according to whether they tasted nice or not. When I got older, it used to affect my choice of girlfriend. Their name would be just as attractive to me as the way they looked or their personality.

You couldn’t go out with somebody who didn’t taste right?
Oh no. There are ways of coping with that, though. If I don’t like the sound or taste of somebody’s name then I’ll try and call them something else in my head. If that doesn’t work then I can’t live with it. A good analogy is meeting somebody who you really like, who looks great and who has a fantastic personality, but has a horrible smell about them. It would affect your perception of them – and it’s always there in the background.

Do you have a girlfriend at the moment?
Yes, she’s called Janette. Funnily enough, she actually tastes like bacon too – slightly thicker bacon, though.

Does synaesthesia affect your relationship?
It is a bit of a problem. Like everyone, Janette likes going out, but I don’t like hanging around in a noisy pub as it can be overwhelming. If it’s quiet then I’m usually ok, but it’s not that enjoyable for me.

How does it affect your relationship with food?
Eating’s always been a bit odd. If I went out, I’d go out with an idea in mind of what I was going to get, probably strong foods with a range of textures. Looking at a menu is just a complication. Menus are described, I assume, to try and stimulate the same thing in you that they do in me naturally – in that you look at something and it’s supposed to make you want it.

Do food words “taste” like the food they describe?
Most of them do, yes. When I eat things I get a synaesthetic taste over the top of it. It works one way, though – if you were to say “Give me a strawberry yoghurt word”, I wouldn’t be able to do it because I’m relying on memory. The other way is totally involuntary and automatic. That’s why I have difficulties answering “What’s the worst word you’ve ever heard?”

Do any food words taste better synaesthetically than the food itself?
If you said “cheese” to me, I get the taste of quite crumbly cheese, but it’s not particularly strong. The name Richard, for example, gives me an extremely strong taste of cheese, but it’s that processed type. That’s quite nice actually, as it’s got a nice, smooth texture and I like the taste of it. There are quite a few words that give me a better taste than the food itself [pause]. I lost track there, I was getting hung up on Richard. All I can think about now is yellow cheese.

Does it make you feel hungry?
I get the taste and I think that I’d love to have a bit to eat now. It’s making me hungry but it’s very easy to turn off – all I have to do is read something and I’m instantly distracted. Time and time again, if I do have the physical food it’s not as nice as the synaesthetic taste.

If you didn’t have to eat, would you be satisfied with synaesthetic eating?
Yeah, definitely. I’ve got a very strange relationship with food. I don’t really need it, I suppose, in the way that other people seem to. It’s totally beyond my comprehension when somebody has to eat just because it’s 7pm.

I’m quite slim and when I do eat I tend to binge eat, a bit like a dog does, so I don’t have to eat again soon. Eating for me is a bore, a chore – I don’t need it.

Does your name evoke any taste in particular?
The taste and texture of my name is chewing gum that’s lost all its flavour. I don’t like my name very much. With your name – Chrissie Giles – I get quite a strong salty taste with the Chrissie bit and the Giles is very difficult to describe, it could be metallic. With the two together, the Chrissie is very strong.

The way someone speaks affects the taste I get, too. At school some of the lecturers would speak very slowly and that used to cause all sorts of trouble. Reading is difficult. I couldn’t go through a piece of text slowly as I’d get caught up on all the tastes, so I have to speedread.

Does music trigger tastes?
Yes, it can be good listening to music. There are certain tracks that are incredible. I was listening to a track by Green Day the other day and it was full of the texture, taste and sweetness of pineapple chunks. There was loads of chocolate, too – the rippled kind you get on top of biscuits.

Tell me about the research you’ve been involved in.
As you can imagine, lexical-gustatory synaesthesia is a very subjective thing. It’s fine for me to say “when I hear x, I taste y”, but anyone could say that. When I first went to a neurologist, they were a bit sceptical and didn’t know what my condition was. They used to give me consistency tests. I’d submit a list of words and the corresponding flavours, then I’d have to come back six months later and they’d give me the list in a different order and check that the flavours I gave matched up. Of course, I could have passed this test just by having a great memory.

Later, I was able to get an MRI scan, which was quite expensive at the time. They did an MRI scan of the brain of a person without synaesthesia while they were eating, and then they scanned my brain as I listened to particular words without eating. The same brain areas lit up.

Did you feel vindicated by this?
Oh yeah, it was a really good moment. Sometimes I used to think to myself that it was just a weird memory trick – but it’s so automatic that I didn’t see how it could be.

Researchers did a ‘tip of the tongue’ test with me once. They showed me things that I didn’t quite recognise, such as a narwhal. I was sitting there trying to think of the name, but I got a taste straight away. When they translated these tastes back to the original list, they found that the name of the object matched the flavour, which was amazing.

It shows you that taste comes first, then I somehow link all this together. It’s an integral part of how I view things. Whenever I think back to past events or holidays, that’s what I think of first – a taste – and then all the pictures come back.

Is it just words that affect you?
Researchers have tried made-up words and non-word sounds and they all trigger a taste. It’s purely the sound of the thing, which is why some foreign languages can cause me problems. I started learning French and German at school. French gave me a horrible overtaste of runny egg, but German tasted nice, like marmalade. It forced the choice about which language to study. I still don’t like French accents.

One of the theories is that this kind of synaesthesia is language based. For example, for me, most words with a ‘je’ sound in (such as ‘college’ or ‘message’) have a sausage flavour.

I also get tastes from colours. I can’t go into my local Sainsbury’s, for example, because the orange everywhere makes me feel awful. It’s a bit like what a gone-off orange would taste like. I can taste it now, just on the corner of my tongue. The word “Sainsbury’s” has the taste and texture of something similar to rhubarb.

How common is synaesthesia?
One study suggested that one in 23 people have it in some form. It can cause problems in education; affected schoolchildren might struggle in noisy environments, for example.

One of the joys of being President of the UK Synaesthesia Association is having people say, “I’ve always done that and I thought I was weird”. People don’t mention it as they think it’s natural, or others have mentioned it and been slapped down. Some people say, “I’ve always thought of Wednesday as green”. Now you can put them under an MRI scanner to find out more.

If you could switch it off, would you?
A technique called transcranial magnetic stimulation can be used to disrupt the neural flow in the brain and switch off the synaesthesia for around 20 minutes. The brain area where the link is in my head is quite deep and might cause other damage, so I haven’t had it done.

To me, having a memory without a taste attached would just be weird. I don’t know how or if I’d remember things. Of the thousands of people with different types of synaesthesia I’ve met, not one would want it taken away. This, to me, is normal; I can’t imagine life without it.

Find out more at the UK Synaesthesia website

Have you ever felt that someone was giving you a funny look? When you sit on the Tube, do you wonder what people are thinking about you? Are you being paranoid, or are your fears entirely justified?

Testing someone’s level of paranoia is very tricky. What if everyone really is after them? Researchers at the Institute of Psychiatry, King’s College London, found an innovative technological solution to this problem. They used virtual reality to create a controlled environment, in this case a Tube train. You might think that people wouldn’t respond to a clearly unreal (as a YouTube commentor has pointed out) situation with feelings of paranoia, but the findings were surprising.

Martha Henson, Multimedia Editor, Wellcome Trust

Watch more of the Trust’s films on our YouTube channel.

Five-year-old Charlie doesn’t speak very clearly, and doesn’t always understand what people are saying. His speech and language therapist says he has a specific language impairment, but his mum thinks he may be deaf. His family doctor refers him to an audiologist, who gives a hearing test and shows that Charlie can detect sounds just as well as other children. The audiologist suggests, however, that he may have an auditory processing disorder, or APD. The family doctor, however, has never heard of APD and is not sure whether it means that Charlie needs a different kind of treatment.

Parents are understandably confused when their child receives multiple diagnoses, some of which may not be found in paediatric textbooks. Use of the APD diagnostic label shows massive geographical variation. The diagnosis is common in the USA and Australia, and rare in the UK. I’ve commented elsewhere on the commercial pressures that may affect the variable use of the term. Here, I want to explain how scientists can go about trying to pinpoint the source of a child’s difficulties.

The field of APD is full of controversy, but let’s start with a point that most people will agree on, namely there’s more to auditory perception than is measured in an audiogram.

An audiogram is the result of a standard hearing test where you are played loud and soft sounds and have to indicate when you can hear them. Poor hearing is often the result of a problem in the peripheral auditory system, i.e. the middle or inner ear. But as well as being able to detect soft sounds: you also have to tell different sounds apart and recognise sounds (see Figure 1). Just as you can be colour-blind despite 20/20 vision, it’s possible to have problems with discrimination and identification of sounds despite having a normal audiogram.

Figure 1. Different stages involved in processing sounds in the brain (see Bishop, D. V. M. (1997). Uncommon Understanding: Development and Disorders of Language Comprehension in Children. Hove: Psychology Press).

Problems of this kind originate in the brain rather than the ear. The ear’s role in hearing is to turn a sound wave into a neural signal. This is then transmitted up the auditory nerve to different brain regions that decode the signal. Studies of adult neurological patients have shown that if certain brain regions are damaged then it can be difficult to interpret what is heard, even though you know a sound occurred. We also know from studies of animals that there are cells in the auditory regions of the brain that respond to specific sound features, such as pitch, duration or spatial location. So it seems entirely plausible that there may be children who have developmental abnormalities of the central auditory system that affect their ability to perceive particular sound features, with consequent knock-on effects on language development.

So why is this controversial? One problem is that nobody can agree on how APD should be defined. From time to time professional groups get together to try and sort out agreed criteria for diagnosis, but this has not led to consensus, perhaps because there is only a slender research basis. One key issue noted by Moore (2006) is that existing tests tend to use speech stimuli to diagnose APD. This leads to ambiguity because poor auditory performance can arise from lack of language skills rather than the other way around. For instance, Japanese listeners often have difficulty distinguishing ‘r’ and ‘l’ sounds, not because there is anything wrong with their hearing, but because their language does not make this distinction. And English speakers do just as poorly when required to distinguish sound contrasts that our own language does not have, such as length contrasts that are used in Finnish.

The importance of language knowledge was made clear in a study that used an American speech-based APD test with children in the UK. They did far worse than American children when tested using speech stimuli delivered in an American accent (Dawes & Bishop, 2007). For this reason, researchers in the UK have developed tests of auditory processing for children that involve sounds such as tones, rather than speech (Moore et al., 2010).

But even this may not sort out the chicken and egg problem of whether an auditory problem causes language difficulties or vice versa. Figure 2 shows possible relationships between these deficits.

Figure 2. Difference explanations for a correlation between auditory processing deficit and poor language skills

Interpretation A is often assumed if auditory deficits are found in a child with language problem, i.e. people assume that the auditory problem has caused the language difficulties. That is a reasonable enough account, given that the child needs to hear language properly to learn it. However, the opposite relation could also explain the results. Suppose children’s language difficulties arose for quite different reasons e.g. problems in interpreting word meanings, so they take longer to learn new words. This might lead them to be less attentive to auditory features, just because they are less skilled interpreters of speech. Or consider the case of listening to a foreign language, where the listener has perfectly normal auditory processing but limited knowledge of the language. Compared to a native Finnish speaker, you or I may have more difficulty hearing differences in the length of two tones just because length differences are important for distinguishing speech sounds in Finnish but not in English. Thus, if we find a correlation between auditory deficit and language deficit, it can be difficult to distinguish interpretation A and B.

To make matters even more complicated, there is also interpretation C, where the co-occurrence of auditory and language deficits does not involve any causal link between the two; instead both deficits arise as the consequence of another factor. What might such a factor be? Well, to take just one example, some children have delayed maturation of certain brain regions. This could impact on a range of skills. Or another example would be a genetic abnormality that affects several different aspects of development.

These different interpretations have important implications for intervention. If interpretation A is correct, then it would make sense to train the child’s auditory skills, as this could have beneficial effects on language. However, if B or C are correct, then auditory training would not be effective.

To disentangle these alternatives we need converging evidence from several sources.  One body of research takes children with language problems as a starting point. It explores their ability to hear different types of sound contrast to establish which, if any, auditory deficits are associated with language difficulties. This might seem like a fairly straightforward question, yet after some 40 years of research there is still considerable disagreement. There are problems both with the evidence itself and with the interpretation of that evidence.

Part of the difficulty in this field arises because young children are not very happy at sitting and making judgements about to hard-to-distinguish sounds for minutes on end. Suppose we want to find out if a child can hear differences between sounds that differ in pitch. Ideally, we want to establish a threshold level at which the difference is just noticeable. So we could play children pairs of sounds and ask them to judge if they are the same or different.

The problem is that the average 7-year-old lasts about two minutes on such a task before asking ‘how much more is there?’ and looking bored. Rather like a parent driving off on holiday with a child in the back seat, the experimenter has the unfortunate task of explaining that there are only another hundred trials to go. Some of my work in this area has been focused on the theoretically unexciting but practically important task of inventing auditory ‘games’ that the child will cheerfully play for long enough to give a sensible auditory discrimination threshold (see Fig 3). Even so, if we find that children with language difficulties do less well than typically-developing children, it can be hard to certain that we have identified a real auditory problem rather than poorer attention or concentration.

Figure 3. Screenshot of auditory discrimination game for children. Each dinosaur makes a noise at it jumps on its box, and the child has to identify which sound is different from the sound made by the central dinosaur. Correct responses are rewarded with cheerful noises and icons on the screen.

Because of this difficulty, I have become interested in alternative methods that do not require the child to attend and explicitly respond to stimuli. Using electrophysiological recording from electrodes situated on the scalp it is possible to measure the minute electrical discharges that occur in the brain when a sound is presented to the ear. By averaging over many stimulus presentations, we can detect a distinct kind of waveform representing activity over time in underlying auditory cortex. Of particular interest is a method whereby we compare the brain responses to different auditory stimuli, such as tones of different pitch or the sounds ‘ba’ and ‘da’.

Unfortunately, although this sounds neat, results are not always consistent from one study to another (Bishop, 2007). In a recent study we found, however, that whereas children with language problems had normal brainwaves at a point that corresponded to stimulus discrimination, they showed abnormalities at a later stage that appeared to reflect stimulus identification (Bishop et al., 2010). This was evident in both school-aged and teenaged children, and was seen for non-speech as well as speech stimuli.

There is a widespread tendency to assume that if you find differences in the brain responses of children with language impairment compared with a control group, that this means you have found the origin of children’s language difficulties.  However, the same logic applies as with the behavioural results (Figure 2): we need to consider interpretations B and C as well as A.

Currently, the field tends to be polarised between those who think auditory deficits are an important cause of children’s language problems (interpretation A), and those who think they are either the consequence of language problems (interpretation B) or an incidental finding (interpretation C). My current view based on research to date? I think auditory processing problems may play a contributory role in causing language and literacy problems, but they are not the cause.

There are several reasons for this conclusion. First, attempts to remediate language difficulties by auditory training have been largely disappointing (Loo et al, 2010). Second, there is mounting evidence that genetic differences between children play an important role in the cause of children’s language difficulties, but this is not so for the auditory deficits that can accompany language problems (Bishop, 2006). The ability to identify and remember the sounds of speech seems to be a specific skill that is crucial for language learning and that can be disrupted in some children, even when their nonlinguistic auditory processing is entirely normal.

In sum, I would be reluctant to throw out the baby with the bathwater and deny any role of auditory impairment in causing problems with language learning, but the evidence to date suggests we should be cautious about using the term ‘auditory processing disorder’. Very often, difficulties in doing auditory tasks reflect the child’s poor language or attentional skills, rather than a primary perceptual cause of their difficulties. An important conclusion from research in this area is that we need more multidisciplinary working between audiology and other professions concerned with developmental disorders to get a fuller picture of how hearing and language problems are related (see Dawes & Bishop, 2009).

Dorothy Bishop

Dorothy Bishop is Professor of Developmental Neuropsychology and a Wellcome Trust Principal Research Fellow at the Department of Experimental Psychology at the University of Oxford. She blogs at BishopBlog and tweets as @deevybee.

References

Fig 1a In vivo brain anatomy of Fragile X syndrome.

The human X chromosome has about 155 million base pairs. Fragile X syndrome is caused by just three of them. The genetic disease, one of the leading causes of inherited mental retardation worldwide, affects around 1 in every 4500 males and 1 in every 9000 females. It is caused by the improper duplication of the three base pair sequence CGG in the gene FMR-1. In Fragile X, this trinucleotide sequence is repeated over 200 times, resulting in inactivation of the gene that produces the FMR-1 protein. Expressed throughout the brain during embryonic maturation, the FMR-1 protein is required for normal development, possibly in the correct formation of synaptic connections between nerve cells.

In a recent paper, Dr Brian Hallahan, from the National University of Ireland, Galway and colleagues in the Institute of Psychiatry, London, used two MRI techniques to compare the brains from a small sample of Fragile X sufferers with those of healthy individuals. The image above shows the relative differences in grey matter volume. Red areas indicate excess matter, while blue indicates a deficit. The images are reversed so the right hand side of the brain can be seen on the left hand side of the image. The results are adjusted for total grey matter volume.

The results of the study suggest that those with Fragile X Syndrome have areas of both increased and reduced volume, with some regions enlarged such as the caudate and others reduced such as the cerebellum. Regional brain differences are seen in both grey and white matter.

If you’re interested in Fragile X, you may also like to watch ‘Tomorrow Belongs to Me‘, a video on the Wellcome Collection website. It looks at the phenomenon of ‘anticipation’ in certain genetic disorders where symptoms occur at progressively earlier stages, and become progressively more serious.

Benjamin Thompson

Image credit: Brian Hallahan

Speech and language were the first ‘functions’ to be associated with particular brain areas. In 1861, Paul Broca described a brain area that appeared to be very important in speech production. The area, in the posterior third of the left inferior frontal gyrus, came to be known as ‘Broca’s area’, and he determined this by studying the brain of one of his patients, known as Tan, who had a brain tumour and could only say the word, “Tan” (in addition to a few, more colourful, words).

Figure 1: the brain of “Tan”, showing a lesion in the left inferior frontal gyrus.

In 1881, Carl Wernicke described lesions in the left temporal lobe (figure 2) that were associated with problems in the perception of spoken language. Both of these findings were incredibly influential, partly because acquired language problems still typically follow damage to the left side of the brain.

Figure 2: Wernicke’s description of the ‘speech receptive area’ in the left temporal lobe marked “x” (Broca’s area is marked “y”).

As one might imagine, 150 years of neuropsychology and neuroscience have enabled us to refine some of our ideas about the neural basis of speech perception and production. One big aspect of this has been to show that the right hemisphere is significantly involved in the perception and production of speech. This contribution can, however, be quite complex. For example, in normal, conversational speech production, the region corresponding to Broca’s area in the right hemisphere is actively suppressed (Blank et al, 2003).

I am interested in what might modulate this suppression. For example, when those with the language disorder Broca’s aphasia recover speech production, this is associated with increased activation in the right hemisphere Broca’s area. But is right Broca’s area associated with other kinds of speech change? We continuously modulate our voices to adapt to our environment, for instance, both in terms of acoustics and social factors. We unconsciously change our voices when we speak in a noisy room, and this change can be quite specific to different kinds of background noise (Cooke and Lu 2010). We also change our voices a lot depending on to whom we are talking – people tell me I talk exactly like my mother after I’ve been speaking with her on the phone, but I can’t tell that I am doing it. In my lab, we are just starting to identify the brain systems involved in this kind of modulation, and it will be interesting to see to what extent and how right hemisphere mechanisms are involved in these changes.

In speech perception, things have become yet more complex. While linguistic information in speech is processed in the left temporal lobe regions that Wernicke described, we also see very strong activation of the right temporal lobe in spoken language. This seems to reflect the fact that, when we speak, we produce an incredibly complex sound – human speech is probably the most complex sound being made by a single sound source. And when we speak we express information not just about the words we say, but also about who we are, where we come from, how old we are, how well we are, whether we are a man or a woman, as well as our mood.

Functional imaging studies indicate that the right temporal lobe areas are especially concerned with processing many of these other aspects of the information in our voices. Thus, the recognition of a speaker is associated with right temporal lobe areas – patients who cannot recognize a speaker by their voice typically have lesions in this area.

Of course, in normal speech perception these factors interact – studies have shown that we very rapidly adapt to speaker-specific idiosyncrasies, but we don’t retune our whole speech perception network (Eisner and McQueen, 2006). Thus, if I hear Jonathan Ross describing a “wed wobin” I am not surprised when the person he’s talking to says “yes, a red robin”. These speaker-specific mechanisms are strong – we understand people better if we are familiar with their voice. It suggests that though the right and left temporal lobes might be sensitive to different aspects of the speech signal, they work together to enable us to understand speech.

The elephant in the room is why linguistic representations and processes are so associated with the brain’s left hemisphere in the first place. The left lateralisation of language is seen in 96 per cent of right-handed people, and is still there in 73 per cent of left-handed people (Knecht et al, 2000). It is there for men and women equally. People whose language centres are not in their left hemisphere have it in their right hemisphere: there is no evidence for people who have an intermediate, more equally divided representation of language across the left and right sides of the brain. And if the language-dominant hemisphere is damaged, the non-dominant hemisphere can take over function. Does this mean that the non-dominant hemisphere still performs linguistic functions in some low-key way? Or that it can adapt following damage to the brain (or perhaps even that it is released from some form of suppression)?

Ideas about why the linguistic aspects of speech perception are left lateralised tend to be a bit circular – one prominent argument is that the left hemisphere is good at processing the acoustic properties of speech. Apart from the evidence for this, why should there be such differences between the left and the right sides of the brain to start with? Is speech perception on the left because speech production is left lateralised? Possibly, but that still leaves the question of why speech production would be left lateralised.

Perhaps by focusing on language we are looking in the wrong place altogether. There are other kinds of asymmetry between the hemispheres. Damage to the right hemisphere can lead to lasting problems with orienting attention in space and time, such as in left spatial neglect, where people do not pay attention to the left side of space, don’t talk to people who stand on that side of them, don’t eat food on that side of their plate and so on. People with left hemisphere damage can show the opposite pattern of ignoring the right-hand side of their world, but this is considered less common and patients tend to recover quickly.

This suggests that there may be differences in how attentional mechanisms operate in the two hemispheres. Along different lines, my UCL colleague Professor Tim Shallice, comes to this problem through his research into high-level thought and monitoring systems. He thinks of the left hemisphere as the side that is good at categorising and classifying objects in the world. When we think about language, it forms a good model in which categorisation and classification are critical processes. I suggest that, in order to understand the lateralisation of language in the human brain, we should keep other, non-linguistic processes in mind.

References

Sophie Scott

Sophie Scott is a Professor of Cognitive Neuroscience at UCL and a Wellcome Trust Senior Research Fellow in Basic Biomedical Science. She blogs at Listening In.

This is part of a series of guest posts from Trust-associated scientists who blog. If you’re a scientist who blogs, we’d love to hear from you. Contact the Editor m.looi@wellcome.ac.uk

Image credits: Nature Neuroscience

Bipolar disorder refers to a mood disorder affecting approximately one in every 100 adults. For those people, severe mood disturbances – either highly elevated or strongly depressed — can make normal functioning extremely difficult.

In this film, we meet ‘Twink’, former photographer for The Jam, who has experienced the extremes of bipolar disorder for more than two decades. Twink is presently a patron of MDF, The Bipolar Organisation, and is passionate about helping Professor Nicholas Craddock, based at the Cardiff University School of Medicine, in his research to discover the underlying genetic factors that lead to this condition.

Nicholas, also featured in the film, was one of the main investigators in the Wellcome Trust Case Control Consortium study, in which around 2000 human genomes were studied for genetic hints as to why certain people develop this mood disorder. He and his team continue to find and scrutinise the DNA of volunteers through the Bipolar Disorder Research Network, the largest study of bipolar disorder in the world, funded by the Wellcome Trust and the Stanley Medical Research Institute.

Akhilesh Reddy

Congratulations to Akhilesh Reddy, who receives the Colworth Medal from the Biochemical Society today.

The Colworth Medal is awarded annually for outstanding research by a young biochemist who has carried out the majority of his or her work in the UK. The medal was donated in 1963 by the Unilever Research Colworth Laboratory and is awarded to a scientist under the age of 35.

Dr Reddy told us, “I’m utterly thrilled and surprised to have received this prestigious award, especially considering the amazing scientists that have won the medal before.”

Reddy is a Wellcome Trust Intermediate Clinical Fellow at the University of Cambridge. He studies circadian rhythms – how organisms sense and adapt to the cycle of night and day. Reddy uses systems biology, proteomics and genome-wide studies to work out how the brain’s clock controls different physiological processes such as the sleep-wake cycle, endocrine rhythms, appetite and various metabolic processes. He recently published back-to-back papers in Nature identifying for the first time the 24-hour rhythms in red blood cells and a similar 24-hour cycle in marine algae, indicating that internal body clocks have always been important, even in ancient forms of life.

Image credit: University of Cambridge Metabolic Research Laboratories

Do we 'decode' changes in the clouds?

Where does our sense of time come from? Recent research suggests external factors play a key part in how our brain perceives the passage of time, writes Misha Ahrens.

Our sense of time passing is important, and typically assumed to originate from timekeeping circuitry within the brain. But a dedicated ‘brain clock’ has not yet been found. We know that our sense of time can be distorted by external events – for example, if people watch a visual scene lasting one second, but showing fast motion, it can appear to last 1.2 seconds.

Our research asked where our sense of time comes from, and whether it partly originates from the outside world. When we judge quantitative aspects of the world, we combine information from multiple senses. Watching a person’s lips, for instance, helps in understanding the verbal content of the sounds they produce. We wondered if our sense of time works in a similar way. Does watching the outside world help shape our sense of duration?

To answer this question, my PhD supervisor Maneesh Sahani and I first showed that, theoretically, there is information about the passage of time in visual scenes we typically observe. Take, for example, the movement of clouds. Larger changes encourage us to believe in longer durations. Because we have an unconscious model for the way clouds change over time and how fast they change shape, on average, we can ‘decode’ the changing of clouds in any particular instance to tell us how fast time might be passing.

Two key experiments suggested that, indeed, part of our time perception is anchored in the outside world. In one experiment, participants watched small circles of light appear on a screen twice in a row. They were then asked to say which appearance lasted longer. When the circles were accompanied by a mottled pattern programmed to change randomly, but at a regular rate, participants’ judgments about the circles were more accurate. This suggests that they used the rate of change in the patterns to help judge the passing of time.

In the second experiment, we asked participants to judge how long a brief presentation of similar mottled patterns lasted, but we varied the rates at which those patterns changed. When the patterns changed faster, participants judged the appearance of the patterns to have lasted longer – again showing that sensory change shapes our sense of time.

People have certain expectations of how fast the world (particularly visual scenes) changes. We argue that, through these expectations, people actually use visual perceptions of the world as a type of clock. Watching a clock or hourglass clearly improves one’s accuracy of how quickly time passes, but we show, theoretically, that it is possible to also derive information about time from, say, watching clouds change shape. Comparing the changes we see to the ‘average’ rate we expect helps us judge how much time has passed, and refines our internal timekeeping. Similarly, it appears that watching a stimulus, even if it is fairly random, can improve one’s accuracy at judging time intervals.

The fact that we can bias people’s perception of time does not fit with the theory of a rigid internal brain clock. Instead, time perception is rooted not only within the brain, but also in our experience of the outside world.

Misha Ahrens

Misha Ahrens is a Sir Henry Wellcome Postdoctoral Fellow at the University of Cambridge and conducted this study with Dr Maneesh Sahani of the Gatsby Unit, UCL.

Image credit: Mark, Vicki, Ellaura and Mason on Flickr

What makes us all unique? Can you tell what job someone does just by looking at a picture of their brain? Can a brain scan be a portrait? Me, Myself and MRI is a chance to explore these questions and lots more while exploring the idea of identity, writes Kirsty Halliday.

It all started back in Autumn 2006 when sound artist Damian Murphy had an MRI brain scan as part of a colleague’s research project. Around the same time, we saw Marc Quinn’s DNA portrait of Sir John Sulston as part of an exhibition by the National Portrait Gallery. Looking at the portrait and the images from Damian’s scan, we got to thinking about alternative forms of portraiture and the use of biomedical data in artworks and the crossovers and links between science and art.

Me, Myself and MRI began in December 2007 with an 18-month education project, working with KS3 pupils from Archbishop Holgate’s School in York to explore topics including MRI technology (with two site visits to York Neuroimaging Centre), ethics in science and art, the history of portraiture, individuality (and what makes us all unique) and creative digital media, including video, audio, photography and interactive technology. The aim was to create a touring portraiture exhibition featuring interactive digital portraits that used MRI brain scan data, video, audio and photographs.

The students drove the development of the final exhibition. They selected the six individuals whose portraits feature in the exhibition, devised the interview questions that were used for the audio and video portraits, created the briefs for the project artists, tested prototypes and steered the design of the exhibition publicity and signage.

The exhibition launched in Spring 2009, with portraits of six people from different walks of life – a TV presenter, a science teacher, a writer, a nurse, a kickboxing champion and a chaplain. It was fantastic to see the artworks out in the public domain and watch how people interacted with them. Some folk seem to prefer standing in the middle of the room, listening to the hubbub of conversation between the portraits and the background sounds of the MRI machine, others like to spend time with each individual portrait, hearing them talk about their heroes, their aspirations and their memories. We invited visitors to tell us what was in their brain that day. The responses showed that the thoughts and ideas that occupy our minds are as varied and unique to us as individuals as our physical appearance is.

A new website has been created to document the project and the exhibition, offer lesson plans and other educational resources for all of the topics we covered and provide information on the artworks to support future touring. We hope that the site offers an insight into the project and the ideas we explored as well as providing inspiration and ideas to support people in developing their own creative projects. Take a look and let us know what you think… www.memyselfandmri.org

Kirsty Halliday, Project Manager, Me, Myself and MRI

Me, Myself and MRI is part-funded by an Arts Award from the Wellcome Trust.

Image credits: Kippa Matthews

Jumpers for goal posts

When studying eye movement, it is easy to imagine someone sitting in a darkened room, following a dot around a computer screen. New research suggests that the future of this research may require a shifting of the goal posts.

Dr Christina Howard and colleagues from the Department of Experimental Psychology, University of Bristol describe a more dynamic system, using video of real world, real time, events.

The work used a video of a 5-a-side football match (filmed by Dr Howard, perched precariously on a building’s fire escape) to study the relationship between eye movements and the judgements people make about the scene they are monitoring. Volunteers were asked to watch a 40 minute match, and indicate via a joystick the likelihood of a goal being scored in the next 30 seconds.

They were asked to keep their hands on the joystick throughout the task, so a continuous judgement of the scene was made. Pushing the stick to its maximum meant that the volunteer believed that there was a 100 per cent chance of a goal, whilst not pushing it at all indicated a zero per cent chance. During the experiment the volunteers’ eyes were tracked using a head-mounted tracker.

Once the match had concluded the volunteers completed a quiz and questionnaire to assess how detailed their knowledge of the sport was ­– they ranged from those who knew little about football to ‘experts’ – mini John Motsons, who live and breathe the game.

The overall results were intriguing. The experts’ eyes responded more quickly to the scene than those of the non-experts, looking at the correct area of the screen faster. However, the experts were slower to react to what they thought was going to happen than the non-experts.

It appears that by getting their eyes in the right place earlier, the expert viewers have more time to consider their response.

Dr Howard likens this to the behaviour of expert tennis players: “As soon as they are aware of where a ball will be returned, they move immediately to that position, giving them the time to select the best stroke”.

By contrast, a novice viewer’s eyes arrive at the correct viewing position late, meaning they have to make quick judgements on what is happening.

The researchers also looked at the accuracy of each group when it came to predicting goals. On paper, you might expect the experts to be better, but surprisingly, there was little difference between the groups, possibly because the task is relatively easy. With the end-to-end nature of a 5-a-side match, when the ball goes near the goal, there is a good chance that the net will soon be rippling.

“This result makes the conclusions even stronger,” explains Dr Howard. “Even though the experts aren’t performing better than non-experts, they are certainly doing the test in a different way.”

She went onto explain that the football aspect of the task is less important than the methodology her team have created. Typically, eye research uses either very brief or simplified lab tasks, but this work looks at a more real world situation.

The researchers hope that this powerful new method might be adopted in other academic fields as well as in the real world environment. They’re currently investigating how CCTV experts are able to accurately and rapidly monitor camera footage to detect how suspicious a scene is.

Benjamin Thompson

Image credit: Jonathan_W on Flickr

Cut-away MRI of brain - level of thalamus

Back in the summer, clinicians and scientists shunned the sunny weather to consider something more insular: brain imaging. Specifically, they gathered at a one day meeting at the Wellcome Trust to explore the thorny issue of what researchers should do when scans of volunteers – taken purely for research purposes – reveal ‘incidental abnormalities’, that is physical anomalies that are outside the scope of the study, which may or may not have health implications for the volunteer.

The problem isn’t explicitly addressed in existing guidelines, although these kinds of findings are surprisingly common. A neurologist at the meeting noted that one in 37 neurologically asymptomatic people going into a brain MRI scanner have an incidental abnormality. Since a roulette wheel has 37 pockets, he likened taking part in this kind of research as a form of ‘brain MRI roulette’.

Delegates at the conference were aiming to reach some sort of consensus on how to fairly treat normal subjects undergoing scans for research, and to establish some sort of guidance for researchers faced with incidental findings in their volunteers’ scans.

The big question is whether – and to what extent – researchers should follow up an incidental finding.

Is it outside their responsibility to do anything at all about an anomaly they find during their research? Or should they tell the volunteer, inform his or her GP, and facilitate or oversee the referrals process for further clinical investigation and even treatment?

More harm than good?

The lack of clear boundaries is compounded by the fact that reporting and acting on an incidental finding may not always be the best thing for the volunteer.

Of course, on the one hand, finding out about these findings can save lives. A cardiologist at the meeting described how a scan he was given as part of a research study unexpectedly revealed an aortic aneurysm with a high risk of sudden death. Finding it significantly increased his chance of survival because he is now being treated and monitored.

Quite often, however, further investigation reveals the finding to be a ‘false positive’ (clinically insignificant). That means the volunteer has needlessly endured a period of stress and uncertainty, which in itself takes a physical toll.

Even if the finding does turn out to be clinically important, there is still the caveat that no medical treatment is 100 per cent safe. They all have their risks and side effects, and sometimes treatment can even do more harm than good – particularly if the volunteer has no symptoms or obvious problems.

Other impacts may include the shock and disempowerment of suddenly, out of the blue, becoming a patient instead of simply a research participant. Job and career loss is possible (if, for example, a scan shows that a train driver or pilot has a brain anomaly), and if the finding is significant, there may be problems getting health and travel insurance.

So in a nutshell, if you volunteer for a research study and get told about a finding, it could be life-saving – but it could also be pretty life-damaging. And it’s not always possible to know which it will be until the finding has been investigated (which means it will also be recorded on your medical records).

The right to remain ignorant

Some volunteers state plainly that they don’t want to know the results of their scans, and they don’t want their GPs to be told about them either. As one speaker at the conference pointed out, the right to personal autonomy includes the right of a research volunteer to choose whether or not to be told about any findings – and whether or not to act on them.

On the other hand, a participant’s right to remain ignorant of research findings has to be balanced against public safety. If a pilot or train driver turns out to have a possible brain tumour, should they be allowed to continue in their jobs unaware of their condition?

Different research centres have different policies. Some allow volunteers to opt out of being told their findings and agree not to notify their GPs. Other centres don’t allow people to take part in research unless they agree to their GP being notified of significant findings.

These differences were reflected in mixed feelings among the conference delegates. Some felt that informing the GP served as a minimum standard or safety net to ensure volunteers with findings could be followed up. Others were concerned about breach of confidentiality, the possibility of compromising the volunteer (who may face future difficulties getting insurance, for example), and infringement of autonomy personal if external regulatory guidance determines when someone should go to their GP and become a patient.

Another important question is whether the principle investigator of the research study should also be notified of an incidental finding, bearing in mind that it might affect the validity of the study. Or again, would this be a breach of confidentiality?

Great expectations

Some of the confusion over what, if anything, to do about incidental findings lies in the expectations of volunteers taking part in research. Some people assume that the scan will be completely anonymous and they won’t be hearing any more about it. Others seem to associate getting into a scanner with medicine. Although it is explained to them during the consent process that the scan is not medical or diagnostic in nature, they expect to get clinical information back from the scan.

Some even volunteer for the study because they have symptoms but are unwilling or afraid to approach the doctor about them, and come for a research scan to get reassurance. There is a real danger of false reassurance, if they haven’t understood that the scan may not be reviewed by a radiologist or clinician.

To screen or not to screen?

One possible way to circumvent the confusion is to include a clinician or radiologist on the research team. They would then be responsible for reviewing scans and following up incidental findings.

Or potential participants could be offered a diagnostic scan prior to the research, which would be examined by an experienced radiologist or clinician, who would decide whether any finding is clinically important. The volunteer could opt to ignore the result – but may be refused participation in the study.

This would solve the problem of false positives – and would also guarantee for the researcher that the volunteer’s body or brain region is in the normal range for the study, with no anomalies that might influence the results.

However, both these measures would significantly increase the costs of research and there simply isn’t enough manpower in terms of the clinical expertise needed to review the scans. As one delegate pointed out, there is simply more research going on than there are expert radiologists. One way around this, which was briefly discussed, may be to have a centralized resource for radiological review of research scans.

Discussing the issues certainly helped elucidate the issue, and as a next step, the organisers and delegates are working together to produce a set of standard procedures – or reasonable ways of doing things – that will help researchers faced with similar dilemmas in the future. This will encourage best imaging research practice in the UK.

There are clearly no easy solutions. However the aim is to incorporate the many different viewpoints heard at the meeting – including the complex responsibility of both researcher and volunteer – within the guidance, and attempt to set a framework within practical limitations.

Penny Bailey

Image credit: Mark Lythgoe & Chloe Hutton. Wellcome Images

Dr Roi Cohen Kadosh

Congratulations to Dr Roi Cohen Kadosh, winner of the Career Development category at the Society of Neuroscience Achievement Awards. The award “recognises promise and achievement in the neuroscience field for early career professionals”.

Dr Cohen Kadosh, a Wellcome Trust Research Career Development Fellow at the University of Oxford, studies the neural basis of number representation. He has developed novel theories on numerical cognition and uses diverse methods in his research, such as functional magnetic resonance imaging, electroencephalography, and transcranial magnetic stimulation. His current research looks to understand developmental and educational failures in numerical processing using behavioural and brain stimulation methods.

Earlier this month, his research showed that applying electrical stimulation to the brain could enhance a person’s mathematical abilities for up to six months.

The Nuffield Council on Bioethics report on Medical Profiling and Online Medicine

‘Personalised medicine’ is a vague but increasingly spouted term these days. No one’s entirely sure what it means, but it encompasses buying Viagra online, consulting your doctor over the internet and having your genome sequenced through one of the many companies on the web. The commercial sector is increasingly offering health services to the consumer. And this raises difficult questions over what the consequences are and how we handle them.

Such questions are a speciality of the Nuffield Council on Bioethics, which prides itself on thoroughly reviewing such topics as they emerge. This week the Council released its report on Medical profiling and online medicine: The ethics of ‘personalised healthcare’ in a consumer age with a special launch event at The Law Society in London.

The title of the report reflects the two main aspects of concern in this broad topic:

• the advent of personal genetic tests and consumer access to imaging scans (such as CT and MRI scans) that consumers can now purchase directly without seeing a doctor, and;
• the increase in public access to health information, advice, diagnosis, medicines and health records, born of the internet.

It all points to more consumer choice in healthcare. That’s often considered to be for the better, but does more choice make for better healthcare decisions? And as a result, how much responsibility must we take on as individuals, when we rely less on the judgements of our doctors and policymakers?

The Council appointed a Working Party of scientists, ethicists, philosophers, sociologists and lawyers, which researched and debated the topic over two years. In the course of their investigation, they considered six case studies that represent the issues at hand:

• The quality and availability of online health information,
• Online personal health records (services that offer a way for the individual to maintain and organise information about their health. Google and Microsoft are among the companies moving into this area),
• Buying medicines online,
• Telemedicine (the use of communications technology to offer health services (e.g. doctor–patient consultation) remotely),
• Personal genetic profiling, often to ascertain one’s risk of developing diseases such as Parkinson’s disease or diabetes,
• Body imaging – from brain scans to whole body imaging.

Each of these are very different and come with their own specific concerns, but looking at the Council’s conclusions and recommendations for all of them, there are common themes:

• Websites containing health information should be transparent about who they are, who funds them, where their information comes from, what that information can realistically be used for – and the possible consequences – and what their users’ rights are.
• Some form of official accreditation for such websites or services is needed.
• Governments need to provide high-quality health information on the internet (something the NHS is already doing) and doctors should direct patients to these sites.
• Doctors will increasingly require specific training and advice on how to care for patients who come to them with medicines or medical information from the internet.
• The fast pace of development means each of these sectors and their impact needs to be monitored closely, and regulation and training adjusted accordingly.

Although this all sounds ominous, the authors are quick to point out that there is so far no evidence of anything going wrong. Indeed, there are numerous positive effects of these technologies delivering benefits around the world, from increasing patient understanding to helping people in remote areas access better healthcare.

The real source of tension, it seems, will be the conflict between the individual and society. How will we balance our demand for extra tests and expensive personal treatments, for example, with the extra strain on nationwide healthcare budgets? How will we weigh up a person’s desire to know of their genetic risk of Parkinson’s disease – driven by the possibility of doing something about it – with the need to regulate such tests and explain the limitations of their interpretation?

As the authors of the report put it:

We need to find ways of balancing individual choice with the principle of social solidarity i.e. that we should share the responsibility to help people in need.

These issues aren’t going to go away – already in the news this week we’ve had scientists exploring genetic profiling by publishing their own genomes and the government investing £50 million to improve genetic testing for cancer drugs. Personalised medicine is becoming more commonplace and more complex, providing more power over your own healthcare. But with great power, comes great responsibility.

You can read the full report and a summary of these issues and more on the Nuffield Council on Bioethics website.

The Nuffield Council on Bioethics is part-funded by the Wellcome Trust.

Image credit: Nuffield Council on Bioethics

Brain falling apart into sky - artwork

While 66 per cent of people with dementia around the world live in low- and middle-income countries, less than 10 per cent of all population-based research into the disease has been carried out in these regions.

The 10/66 Dementia Research Group (its name referring to that imbalance) is a collective of research groups throughout Africa, Asia and South America. Penny Bailey explores the work of the group and the complicated issues surrounding an area of growing concern.

Read the full feature article on The Wellcome Trust website

Image credit: Heidi Cartwright, Wellcome Images

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Carefully carving through the surface of the shiny, quivering pink cortex with his scalpel, neuroscientist Guy Billings traced out a small area of the marvellous human cerebrum. “This,” he said, “is Broca’s area – crucial for the ability to produce language. People who have suffered damage to this region have lost the ability to speak.” The crowd peered in for a closer look.

“Let’s just cut that out then,” said Guy, and plopping the pink shiny piece onto a plate, he handed it out with a shiny pink spoon. It was instantly devoured (and declared delicious).

Don’t worry, this was no cannibal show. The ‘brain’ in question was fashioned by Guerilla Science director Jenny Wong using vanilla panna cotta as white matter and raspberry jelly for grey matter, this life-sized jelly brain was one of three confectionary cortexes we had brought all the way from Jen’s London flat to the Green Man music festival in Wales.

Each day Billings, a researcher at University College London, drew spontaneous crowds of several dozen onlookers with the shiny brains displayed on pink trestle tables in Einstein’s Garden. Intrigued, tantalised, and often grossed-out, guests gorged on bits of orbitofrontal cortex and parietal lobe as he performed al fresco brain surgery, taking them through the history of neuroscience and how we have come to understand the brain – through trial and sometimes regrettable error.

Those intrigued by the taste of brain, could find out more nearby. Food scientists Rachel Edwards-Stuart and Becki Clarke of Nottingham University explored the multifaceted nature of ‘taste’ with a sensory feast of colourings, flavours, and molecular gastronomical treats. These revealed how what we think of as a single sense is actually influenced by what we can see, hear and smell.

Sampling tester strips to search for ‘supertasters’, our diners discovered that not all of them could taste a synthetic chemical and were given a new – and highly tactile – appreciation for the fact that we are all unique organisms with our own suite of sensory characteristics, a truth that many of us can easily forget.

Edible education is a rare treat – especially in the setting of a music festival. But adding a sensory element makes the experience all the more memorable than a straightforward lecture.

“I’m going to close by addressing a popular myth about the brain – that you only use ten per cent of it,” Billings said, as he carefully sliced up the brain. “You need every bit of your brain – it’s all important.”

Zoe Cormier

For more photos see Guerilla Science’s Flickr page. You can find out more about Guerilla Science on their website.

Guerilla Science received funding from a Wellcome Trust People Award.

Image credits: Guerilla Science

Newborn baby

At the UCL Institute of Child Health, Professor David Gadian is working with clinicians including neurologists, cognitive neuroscientists and neurosurgeons to develop safe and non-invasive techniques to diagnose and aid treatment of brain disorders in children.

Professor Gadian has been involved in advancing the medical possibilities of nuclear magnetic resonance techniques since they first began to be used in clinical settings. Penny Bailey spoke to him about his career and how physics is aiding medicine.

Read the full feature on the Wellcome Trust website

Image credit: Jacob Johan on Flickr

The eye of the fly

Prior to meeting them for the first time, I always do some research into the scientists I’m due to film. This time, though, Linda Partridge from UCL’s Institute of Healthy Ageing was a bit different. She is both a professor and a Dame.

I’d not met any double-barrelled scientists before, so it was hard to resist Googling the full extent of Professor Dame Linda Partridge’s achievements. I have to admit she was a bit intimidating on paper. However, when I told her this, she casually replied, “Live long enough and it’s easy to look impressive” which was an effective way to put me at my ease.

Linda is just the sort of scientist you’d hope would be investigating Alzheimer’s disease.

Critical to her research are fruit flies. Researchers of Drosophila melanogaster – in scientific parlance – have been plundering their genetic secrets for years. For a variety of reasons, including ease of rearing and speed of growth, the Drosophila genome has become one of the most widely used sources of information and inspiration for scientists bent on understanding complex life.

Drs Fiona Kerr and Oyinkan Adesakin from Linda’s ‘buzzing’ lab (you quickly discover that not every fruit fly is happy to remain confined), walked me through the process of how the flies are cared for and studied: temperature and light regulated rooms filled with what appear to be old milk bottles, each containing flies in various states of development. In other words, bottle upon bottle of genetic questions hopefully being answered.

A fly’s entire lifespan is just 80-90 days long, which comes in handy for genetic studies. It’s possible to introduce some form of genetic alteration and days later have a read out of the consequences of that change. Kerr and Adesakin are examining what happens when the genes suspected of causing Alzheimer’s disease in humans (tau and amyloid-β peptide) are introduced into flies.

By introducing these genes and influencing the tissues in which they are produced, Partridge’s team are learning how they result in the toxicity that ultimately leads to a neurone’s demise, and subsequently to Alzheimer’s disease.

‘How do you know whether a fly is demented?’ said the Dame Professor, clearly anticipating my next question. The answer is both surprising and elegant:

Barry Gibb, Multimedia Editor, Wellcome Trust

Image credit: David Strutt, Wellcome Images

Dr Thierry Chaminade and his robot

Many people expect that humans and robots will interact more frequently in the near future. For this reason, it is extremely important that robots are capable of smooth and natural movements so that they do not make people feel uncomfortable.

Dr Thierry Chaminade from the Wellcome Trust Centre for Neuroimaging is part of an international research group that last month published a paper on the human brain’s response to humanoid robots. In the study, the researchers scanned the brains of volunteers with functional magnetic resonance imaging (fMRI) while they watched video clips of people and a humanoid robot expressing the same emotions.

I spoke to Dr Chaminade about the paper, and the worlds of robotics and neuroimaging.

Are robots often used in neuroscience?

There hasn’t been a lot of work in this area. Our paper is one of the first studies that tries to really look at how we perceive robots, with the aim of understanding social cognition. For that reason it was a tough challenge to get it published, because it was not deemed as relevant by either roboticists or neuroscientists. Roboticists are not interested in the brain and neuroscientists don’t care about robotics. We had a hard time explaining why this research is interesting to both groups.

What was the basis for this study?

The uncanny valley says that if you make a robot too human it becomes superfluous. This made me question – what happens if it does not really look like a human? We were trying to figure out how the perceptual system deals with these human-like but imperfect appearances.

As we expected, the system that we use to perceive human actions is simply not activated by the robot stimuli. However, we discovered that we can actually cheat the system by telling it to perceive what the robot is doing as an emotion.

When we asked the subjects to judge the robot using human names for emotions, for example ‘How happy was the robot?’ or ‘How disgusted was the robot?’ this actually primed the system to be more responsive to the robot. This was quite unexpected, and may provide interesting hypotheses for future work (watch a video of the experiments here (MP4 0.43 MB)).

If we tell people that the robot is portraying human emotions, or maybe that it is being controlled by a human, people may be more likely to resonate with the robot than if we show it to them without giving them any information. That is quite interesting, because it is something that will be quite important in the future when more robots are being made – the way you present your robot can make a huge difference in the way that people perceive it.

In the paper, you mention social care for the elderly and cognitive therapy as possible applications for robotics.

There are several robotic animals, such as a baby seal, that have been developed as companions for the elderly. A lot of people are working on robots for cognitive therapy as well. These robots could be very useful in rehabilitation therapies for children with autism in particular. Some researchers suggest that children with autism are missing some stages in their social learning because they often avoid contact with other people.

One of the hypotheses is that they avoid contact because they experience a repulsion for some things in humans that we haven’t identified. For example, it is often noticed that they avoid eye contact. Others may be afraid of the complexity of human cognition, so they cannot really read it.

Researchers have observed, however, that many of these children and young adults are keen on new technologies and can often communicate better through online messaging tools than with a real person, face-to-face. There have also been several observations that children with autism may be attracted to features in a robot that they will avoid in other people. Taking the earlier example of the eyes, they will often not make eye contact or follow the gaze of a person, but there have been cases where they approach a robot, touching its eyes, trying to figure out what the robot is looking at.

All of these things support the hypothesis that robots could be used as learning tools for these kids, for things that they have more difficulty learning from a person like other people do. We could help them to learn things that are important for normal social interactions, such as gaze following, pointing to objects, or trying to understand mental states or emotions of other people. It’s one of the promising direct applications of humanoid robotics in everyday life.

The study involved researchers from all over the world. How was the work divided between you?

We had three groups. The Japanese team, including Massimiliano Zecca and Atsuo Takanishi, actually built the robot.

The Italian team were the source of the idea; they have done other work on mirror neurons – brain cells that you use when you perceive other people’s actions in a process called motor resonance. Our original question was: do you use motor resonance when you see non-human actions? Simply put, are mirror neurons responsive to humanoid robots?

The UK-based group, including me, did the fMRI and all of the associated work to investigate this question. To tell you the truth there are some co-authors of the paper I have not met in person yet!

What do you think is the future of robotic technology?

The direction that robotics will take depends on what is funded. There is a highly problematic issue in this respect – what use can we make of these robots? It’s really an issue in the short-term, people have problems getting funded in robotics simply because there are no clear applications to building humanoids. So then the question becomes more about the long-term use of these robots, which is not entirely clear.

Those things being said, other advances are being made as a direct consequence of humanoid technology. Things like exoskeletons – frameworks developed with robot technology that can be attached to the body – are useful for people with hemiplegia (where the limbs on one side of the body have a severe weakness). There are even some exoskeletons being developed to help people to walk again, or to use their arms again. It’s not a direct application of humanoid robots, but it uses technology that came from the development of complex robots.

• Chaminade, T., Zecca, M., Blakemore, S., Takanishi, A., Frith, C., Micera, S., Dario, P., Rizzolatti, G., Gallese, V., & Umiltà, M. (2010). Brain Response to a Humanoid Robot in Areas Implicated in the Perception of Human Emotional Gestures PLoS ONE, 5 (7) DOI: 10.1371/journal.pone.0011577

Ailbhe Goodbody

Ailbhe Goodbody is undertaking a work experience placement at the Wellcome Trust.

Image credit: Thierry Chaminade