Month: August 2008

YouTribe

Anthropologist Michael Wesch gave a thoughtful and engaging talk on ‘An anthropological introduction to YouTube’ to the Library of Congress earlier this year and, rather appropriately, it’s available online as a video on the popular video sharing site.

Wesh runs a digital ethnography project which looks at how cultures form and operate on the net.

The project’s blog is also full of fascinating insights and is well worth checking out if you thought anthropology was only ever about people who don’t have electricity.

Link to talk ‘An anthropological introduction to YouTube’.

‘Anti-torture’ candidate to run for APA presidency

Despite the American Psychological Association revising their ethics policy twice in the debate over American psychologists’ participation in war-on-terror interrogations, significant unrest still remains over the fact the APA has yet to actually enforce its reluctantly implemented ban.

The Boston Globe has an op-ed article by psychologist and APA critic Stephen Soldz who notes that an anti-torture candidate has been put forward for the APA presidency in an attempt to force the Association’s hand.

The new candidate is psychologist Steven Reisner who even has a campaign website – an innovation for presidential elections which are usually wildly underwhelming.

According to the Globe piece, Reisner received the most votes of the five candidates in the nomination phase. If the momentum carries forward, APA’s careful tiptoeing to avoid offending the US military may backfire if the most political president for years takes the helm.

Interestingly, both Soldz and Reisner are psychoanalysts, a group who have been leading the campaign against psychologists’ role in US military interrogations and who have consistently opposed the ‘war-on-terror’ since it began.

Freud himself was particularly interested in the tension between individual drives and governmental control. In Civilization and its Discontents he suggested government was an inevitable result of the need to control the unacceptable desires we all have.

He was particularly interested in how common individual neuroses get expressed socially as we project our own fears onto specific groups deemed to be ‘outsiders’, often with barbarous and disastrous consequences.

Link to Boston Globe op-ed.

Hypnosis addiction: the scourge of the Victorian lady

I’m currently reading the wonderful but very long book The Discovery of the Unconscious which I shall post more about later.

However, I noticed this little gem about hypnosis in the late 1800s which just smacks of the current hand-wringing over the non-existent (or rather can’t-existent) ‘internet addiction’.

The problems described are so obviously not addiction, and, in fact, like the internet, there’s no specific activity to be addicted to that is defined by the term ‘hypnosis’. After all hypnosis is just where you concentrate and someone makes suggestions – can you be addicted to concentration and listening? Obviously not.

Nevertheless, the concerns got framed in the language of addiction as a placemarker for a fear of the unknown and as a fig leaf for other social problems (from p118):

Deleuze and the early mesmerists also described the evils resulting from too frequent or too prolonged hypnotic sessions. Such subjects gradually became addicted to hypnosis: not only did their need for frequent hypnotization increase, but they became dependent on their particular magnetizer, and this dependency could often take on a sexual slant. This well-known fact was rediscovered by Charcot, who gave an account of a woman who had been hypnotized five times within three weeks and who could think of nothing but her hypnotist, until she ran away from her home to live with him. Her husband took her back, but she fell into severe hysterical disturbances that necessitated her admission to a hospital.

Link to Wikipedia page on The Discovery of the Unconscious.

Interrupting Napoleon on the genetics of mental illness

Today’s Nature has got an interesting letter on psychiatric genetics suggesting an interesting approach to studying the genetics of mental illness.

It’s from neuroscientists John McGrath and Jean-Paul Selten and comments on an earlier Nature article which we discussed previously.

Napoleon Bonaparte advised: “Never interrupt your enemy when he is making a mistake.” Those of us who assess the contribution of non-heritable risk factors to neuropsychiatric illness would like to politely interrupt this battle to remind opponents that environmental risk factors have now overtaken genetic factors with respect to both effect size and the proportion of the population that is affected.

For schizophrenia, for example, factors relating to urban birth, cannabis use and migrant status are well replicated and have relatively large effects ‚Äî in contrast to the scant evidence that remains after decades of genetics research. Although the ‘heritability index’ for schizophrenia is large (about 85%), this metric encompasses the neglected contribution of gene‚Äìenvironment interactions, as well as the high-profile genetic component. This key point is largely forgotten in the heat of the battle.

It has been convincingly argued (A. Caspi and T. E. Moffitt Nature Rev. Neurosci. 7, 583‚Äì590; 2006) that the power to detect genuine genetic-susceptibility loci would be substantially increased if we could stratify samples according to environmental risk factors. Let’s have more funding to help fine-map the wide range of non-heritable risk factors associated with disabling disorders such as schizophrenia and depression, and discover how they act. These clues are too valuable to overlook.

It’s an interesting point and is relevant to the fact that heritability must be one of the most misinterpreted statistics in genetics.

If a study reports that schizophrenia has a heritability of 85%, many people interpret it to mean that 85% of the risk of developing schizophrenia comes from genetics and this is something to do with the condition itself.

In fact, what it shows is that 85% of the risk of schizophrenia in the samples taken so far is estimated to come from genetics, but crucially this estimate is dependent on the environment in quite subtle ways.

The letter above mentions gene-environment interactions: where exactly the same genes can produce different heritability depending on the environment.

Imagine that everyone lived in a virtually identical environment and we all had almost exactly the same life experiences. The only possible difference in the prevalence of mental disorder would have to come from genetics, because the environment is virtually the same for everyone. In this case, heritability would be close to 100%.

Alternatively, if the environment was widely different for everyone, much more of the difference would come from experience and so the heritability estimate would be less.

In other words, the estimate of heritability depends partly on the variability in the environment experienced by the people being studied.

I was told by a genetics researcher that studies on the genetics of intelligence in school children tend to show that IQ is more heritable in the UK than the US, because in the UK we have a National Curriculum – a specified education programme that every child follows.

This means that UK children have a more similar learning environment, whereas in the US the curriculum is decided state-by-state meaning there’s much more variability in experience. Hence, IQ is less heritable in US school children.

I’ve not found the the studies on IQ in school children, so I’m not sure how it stands at the moment, but it serves as a good illustration of how heritability estimates can be environment dependent.

Actually, this week’s Nature has two other letters on the same topic, and additional feature articles on autism and neural synchrony, as well as a couple brain-relevant book reviews.

Link to contents of this week’s Nature.
pdf of Nature Reviews Genetics paper on twin studies and heritability.

FBI’s Most Wanted neuroscientist on imitation

Aafia Siddiqui was the FBI’s Most Wanted Woman for several years and is currently in US custody in New York, awaiting trial on charges that she is a terrorist and member of Al-Qaeda.

She is also a neuroscientist and co-authored a scientific paper in 2005 on the cognitive science of imitation learning.

Before her recent capture, which some sources claim may have actually happened five years ago in Pakistan, Siddiqui completed a PhD entitled ‘Separating the components of imitation’ at Brandeis University in the US.

Before that, she completed a Masters degree in neuroscience, also on imitation learning, and her 2005 paper is based on her work for this degree.

The paper describes three experiments that attempt to understand how our learning of seen actions is affected by delays, memory interference and visual interference.

Each experiment involved a pale red disc that followed an ‘invisible track’ on a computer monitor. The sort of track is illustrated in the diagram of the left, although in the actual experiment the participants just saw the disc.

In Siddiqui’s experiment, one group of participants used a trackpad to ensure that the cursor was within the disc at all times (a classic pursuit-tracking task), while another group had to wait until the disc had followed the route before trying to reproduce it from memory.

To look at the effect of complexity on imitation learning, some routes had only three straight lines, while others had up to seven.

Furthermore, some routes were repeated, while others appeared only once. This allowed the researchers to compare learning for identical routes (specific learning) with learning for the general task (skill learning).

The results showed that, unsurprisingly, participants were better at reproducing the simpler routes. What was more surprisingly though, was that practice-related improvement was only seen when participants watched the whole movement before starting, and then only on routes that were repeated.

Intriguingly, when interviewed after the experiment, the participants had no idea some routes were presented more than once, suggesting that this learning occurred without any conscious involvement.

A further experiment showed that delays of up to 6 seconds barely affected performance and that interfering with short-term memory by getting participants to do maths problems only made them a little worse.

Finally, the researchers ran an experiment where the disc appeared only at the beginning and end of each straight line, or when it was turning a corner. This had virtually no impact on performance. Participants were almost equally as good with much less information.

The research helps us understand the limits of learning when we need to copy a certain action sequence, be this tying shoelaces, swinging a golf club or learning tai chi.

The study suggests that for short action sequences we may be better off waiting until we watch the whole thing before attempting it ourselves.

Link to PubMed entry for paper.
Link to library record for Siddiqui’s PhD thesis.

The common language of pride and shame

Wired Science covers an elegant study that suggests that spontaneous expressions of pride and shame are innate behaviours that are not significantly influenced by culture.

The researchers came up with the ingenious idea of comparing how judo wrestlers from the 2004 Olympics and blind judo wrestlers from the 2004 Paralympics celebrated and commiserated their matches.

This allowed a cross cultural comparison, but it also allowed a comparison with blind athletes who have never seen another person in the same position to copy their behaviour.

The new research, however, distilled from high-resolution, high-speed photographic sequences of sighted and blind judo competitors at the 2004 Olympics and Paralympics, suggests that most nonverbal responses to wins and losses are almost universal.

No cultural differences were observed among competitors from different countries and, aside from the shaking of the fists after a loss, sighted and blind athletes displayed remarkably similar nonverbal behavior.

In other words, it made virtually no difference what culture each individual came from, or even whether the person had seen another wrestler at the end of a match or not – the expression of pride was indistinguishable, suggesting that this may be a common expression that we all share.

There was a slight effect of culture on the expression of shame – as the researchers note “it was less pronounced among individuals from highly individualistic, self-expression-valuing cultures, primarily in North America and West Eurasia”.

However, as there was no difference within cultures between sighted and blind individuals, they further suggest that both pride and shame are likely to be innate, but that shame display may be intentionally inhibited by some sighted individuals in accordance with cultural norms.

Link to Wired Science on elegant study.
Link to full text of paper.

George Lakoff and the linguistics wars

George Lakoff is famous for being one of the founding fathers of cognitive linguistics, for battling Noam Chomsky, and for arguing that using the right metaphors is the key to winning a political debate.

He’s profiled in an article for the Chronical Review which serves as a fantastic introduction to the man, his work and his controversial foray into politics.

Lakoff is particularly interesting because he advised the US Democratic party on the use of language and in ‘framing’ debates – meaning they are described with metaphors that automatically conjure up positive ideas and concepts that are favourable to the policy under discussion.

Whether you share Lakoff’s politics or not, the story of how he became prized by the party and then embroiled in a backlash over whether this was just gloss and glitter rather than anything of political substance is interesting.

The roots of the cognitive revolution in the social sciences are numerous and wide-ranging, but Lakoff traces his own story to Berkeley in 1975, when he attended a series of lectures that prompted him to embrace a theory of the mind that is fully embodied. Lakoff came to believe that reason is shaped by the sensory-motor system of the brain and the body. That idea ran counter to the longstanding belief — Lakoff traces it back 2,500 years to Plato — that reason is disembodied and that one can make a meaningful distinction between mind and body.

One of the most influential lectures Lakoff heard that summer was delivered by Charles J. Fillmore, now an emeritus professor of linguistics at the university, who was developing the idea of “frame semantics” ‚Äî the theory that words automatically bring to mind bundles of ideas, narratives, emotions, and images. He called those related concepts “frames,” and he posited that they are strengthened when certain words and phrases are repeated. That suggested that language arises from neural circuitry linking many distinct areas of the brain. In other words, language can’t be studied independently of the brain and body. Lakoff concluded that linguistics must take into account cognitive science.

The field of cognitive linguistics was born, and Lakoff became one of its most prominent champions. But it wasn’t until the mid-1990s that he began thinking through some of the political implications of framing. Startled by the Republican takeover of the House of Representatives in 1994, Lakoff set about looking for conceptual coherence in what he saw as the seemingly arbitrary positions that defined modern conservatism. What thread connected a pro-life stance with opposition to many social programs, or a hostility toward taxes with support of the death penalty? Lakoff concluded that conservatives and liberals are divided by distinct worldviews based on the metaphor of the nation as a family.

The fact that throughout Lakoff was trying to apply the cognitive science of language to a practical problem makes for an interesting tension between science, speculation and ambition.

Link to article ‘Who Framed George Lakoff?’.

Mainlining the active ingredients of cannabis

I’ve uploaded a fascinating video clip where a TV presenter is intravenously injected with the active ingredients of cannabis as part of the BBC documentary Should I Smoke Dope?

It’s part of an experiment to compare the effects of intravenous THC and cannabidiol combined, with intravenous THC on its own. The mix of both gives the presenter a pleasant giggly high while THC on its own causes her to become desolate and paranoid.

Both are these are known to be key psychoactive ingredients in cannabis but the video is interesting as it is a reflection of the fact that THC has been most linked to an increased risk of developing psychosis while cannabidiol seems to have an antipsychotic effect.

As we discussed earlier this year, one study found that cannabis smokers who had higher levels of cannabidiol in hair samples had the lowest levels of psychosis-like experiences.

Another study we covered reported that, at least in the UK, ‘skunk’ has virtually no cannabidiol, while hash, although variable, was more likely to contain high cannabidiol levels.

And if you’re after a more balanced view on the link between cannabis and psychosis than you normally get in the media, I’ve also uploaded a clip from the same programme where psychiatrist and leading cannabis researcher Robin Murray discusses the findings from the latest research.

If you want to check out the whole documentary, where BBC reporter Nicky Taylor gets stoned for 30 days in a row while investigating the science, culture and legal status of cannabis, it’s available as a torrent or in six parts on YouTube (1, 2, 3, 4, 5, 6).

Link to video of IV cannabidiol and THC experiment.
Link to video of psychiatrist Robin Murray on cannabis and psychosis.

Parapsychology in a nutshell

Today’s featured article on Wikipedia is a rather splendid article on parapsychology – the scientific study of the supposed paranormal phenomena of the mind.

Academic parapsychology is notable for the exceptional quality of the experiments it conducts and the inconclusive nature of its findings – at least to mainstream science.

Large reviews of many studies (meta-analyses) tend to find that ‘psi’ effects are statistically significant but of small effect. The disagreement comes in over whether this small effect is a genuine reflection of paranormal ability or just an artefact of research – such as negative findings being published less often.

The history and process are fascinating though, with some of the great luminaries of psychology, such as William James, having been interested in experimental studies of psychic powers.

Link to Wikipedia page on ‘parapsychology’.

Cannibalism, prions and encephalopathy (oh my!)

Cannabalism gave Western medicine its first understanding of prion diseases as an epidemic of the neurological disorder swept the South Fore tribe in Papua New Guinea. Neurophilosophy has written a remarkably lucid article on the history and neuroscience of how prion diseases, of which ‘mad cow disease’ is one, affect the brain.

The piece starts with some archive footage of a tribe member with the devastating disorder and continues to describe how this class of diseases are probably caused by misfolded proteins that can trigger the same misfolding in other proteins leading to a chain reaction of neural damage.

The Fore tribe had a tradition of ritually consuming the brain and body of deceased relatives, which likely lead to the outbreak.

The word kuru means “shaking death” in the Fore language, and describes the characteristic symptoms of the disease. Because it affects mainly the cerebellum, a part of the brain involved in the co-ordination of movement, the first symptoms to manifest themselves in those infected with the disease would typically be an unsteady gait and tremors. As the disease progresses, victims become unable to stand or eat, and eventually die between 6-12 months after the symptoms first appear.

Kuru belongs to a class of progressive neurodegenerative diseases called the transmissible spongiform encephalopathies (TSEs), which also includes variant Creutzfeldt-Jakob Disease (vCJD) and bovine spongiform encephalopathy (BSE, more popularly known as “Mad Cow Disease”). TSEs are fatal and infectious; in humans, they are relatively rare, and can arise sporadically, by infection, or because of genetic mutations. They are unusual in that the infectious agent which transmits the diseases is believed to a misfolded protein. (Hence, the TSEs are also referred to as the prion diseases, “prion” being a shortened form of the term “proteinaceous infectious particle”).

Prion diseases are a complicated area and you probably won’t find a better written introduction that captures both the science and the intrigue of these relatively new disorders.

Link to article ‘Cannibalism and the shaking death’.

The best is yet to come: reward prediction in the brain

Jonah Lehrer has written an excellent piece for the latest issue of Seed Magazine on the work of neuroscientist Read Montague who’s been discovering the essential function of dopamine in predicting rewards.

Reward prediction is the process where dopamine neurons fire when a reward is expected and also seem to code the amount of error between the prediction and what actually happens. Importantly, the process seems to be accurately described by an algorithm that was already used in computer science.

This has been an area of intense interest over the last decade as it ties together neurobiology, learning, motivation, mathematics and can be demonstrated in a variety of simple lab-based tasks. The fact that dopamine has been linked to numerous disorders in the past makes it a popular paradigm in which to understand psychiatric symptoms.

The Seed article looks at the work of Read Montague who has been studying the process and has been using ingenious methods to look at the role of this system in social reasoning.

In recent years Montague has shown how this basic computational mechanism is a fundamental feature of the human mind. Consider a paper on the neural foundations of trust, recently published in Science. The experiment was born out of Montague’s frustration with the limitations of conventional fMRI. “The most unrealistic element [of fMRI experiments] is that we could only study the brain by itself,” Montague says. “But when are brains ever by themselves?” And so Montague pioneered a technique known as hyper-scanning, allowing subjects in different fMRI machines to interact in real time. His experiment revolved around a simple economic game in which getting the maximum reward required the strangers to trust one another. However, if one of the players grew especially selfish, he or she could always steal from the pot and erase the tenuous bond of trust. By monitoring the players’ brains, Montague was able to predict whether or not someone would steal money several seconds before the theft actually occurred. The secret was a cortical area known as the caudate nucleus, which closely tracked the payouts from the other player. Montague noticed that whenever the caudate exhibited reduced activity, trust tended to break down.

One thing I notice a little of in the quotes from Montague, which is incredibly common in discussion of dopamine and reward, is a kind of ‘reward system dogma’.

Reward is usually linked to the function of the striatum and nucleus accumbens and the dogma goes something like this: “no matter what is happening when the nucleus accumbens or striatum is activated, something about the activity is rewarding”.

I was interesting to read a recent study comparing brain activation in people with ‘normal’ and ‘complicated’ (i.e. extreme) grief in response to viewing pictures of their deceased relative.

The study found additional nucleus accumbens activation in people with complicated grief and suggested that this reflects the fact they find the thoughts of them more rewarding. This is despite the fact that the nucleus accumbens has also been found to also represent salience – i.e. how likely something is to grab our attention.

It’s probably also worth mentioning that there may be some serious problems with the elegant reward prediction theory of dopamine which are were outline in a 2006 paper in Nature Reviews Neuroscience and summarised by the excellent Developing Intelligence.

The Seed is generally an excellent read though and covers an important finding and some innovative new ideas. I especially like the fMRI machines linked in parallel, like multi-player arcade machines.

Link to Seed article ‘A New State of Mind’.

Digital drugs emergency – paging Dr. Beat

USA Today has an unintentionally hilarious article on the dangers of ‘digital drugs’ that can supposedly mimic the effects of alcohol, marijuana, LSD, crack, heroin, sex, heaven and hell.

Woohoo! I hear you shout, before realising the article is actually a woefully misinformed piece about binaural beats, a fascinating but harmless phenomenon when two pure tones of close but differing frequencies are played, one in each ear.

This can produce a perception of a pulse or a ‘beat’ which isn’t actually present in the sound but is a result of our brain making sense of the tones.

You need headphones to get the effect properly and there’s a couple of examples on the Wikipedia page (ignore the ‘hypothetical effects on brain function’ section though, it’s currently full of drivel and miscited experiments).

The fact that it causes a ‘pulsing’ in the brain has led to lots of websites suggesting it can ‘synchronise your brain waves’ – and whenever ‘synchronising brain waves’ is mentioned you can be sure they’ll be lots of nonsense about ascending to higher states of consciousness, super mind power and legal LSD being mentioned.

Actually, there are a minority of people who can have their state of consciousness altered by flashes of light at certain frequencies.

In fact, it may trigger full blown seizures in some (photosensitive epilepsy) but also causes minor and subtle seizure activity in others and in some can stimulate memories or images, or perhaps just cause an ‘odd’ feeling.

This was the basis of the original ‘dream machine‘ and subsequent electronic versions which flash lights in your eyes. The history and neuroscience of this discovery was retold in the excellent book Chapel of Extreme Experience if you’re interested.

Some preliminary research has shown that binaural beat audio can decrease anxiety or boost mood, but the studies are small and inconclusive and some are published in what we might tactfully refer to as ‘non-mainstream’ journals.

In the vast majority of people though, flashing lights or auditory pulses of whatever type do bugger all on their own, despite what various New Age websites and YouTube videos try and convince you (infinite bliss anyone?).

The USA Today piece manages to swallow this hook, line and sinker to fantastic comic effect:

Different types of digital drugs

Some sites provide binaural beats that have innocuous effects. For example, some claim to help you develop extrasensory powers like telepathy and psychokinesis.

Other sites offer therapeutic binaural beats. They help you relax or meditate. Some allegedly help you overcome addiction or anxiety. Others purport to help you lose weight or eliminate gray hair.

However, most sites are more sinister. They sell audio files (“doses”) that supposedly mimic the effects of alcohol and marijuana.

But it doesn’t end there. You’ll find doses that purportedly mimic the effects of LSD, crack, heroin and other hard drugs. There are also doses of a sexual nature. I even found ones that supposedly simulate heaven and hell.

There’s plenty more great entertainment in the article. Life imitates Chris Morris, again.

Hey, I’m having a comedown from my infinite bliss.

I want my money back.

Link to ‘Web delivers new worry for parents: Digital drugs’ (via MeFi).

Preminiscence

Over the past year, I’ve had the pleasure of working with a fantastic theatre company and some amazingly talented composers to help develop a play called Reminiscence about a woman who hallucinates music after developing temporal lobe epilepsy.

The play premiers in London on September 9th and will be accompanied by talks discussing the neuroscience of hallucinations, music and the ethics of treating personally meaningful neurological symptoms.


 

It’s based on one of Oliver Sacks’ case studies (Mrs O’C) that he featured in both The Man Who Mistook His Wife for a Hat and Musicophilia but has been updated and expanded to explore how neuropsychology and medicine deal with the situation when pathology and personal meaning collide. The piece is wonderfully engaging and combines music, visual and theatre to powerful effect.

The idea originated from composers Effy and Litha Efthymiou who were inspired by the musical aspect of Sacks’ case and who began working with the theatre daCapo company to develop a production.

I was honoured to be asked to advise on the neuroscience, and have spent an immensely enjoyable year working with the company. Needless to say, I’m incredibly excited to see it in its final stages and can’t wait until in premiers in the Jacksons Lane theatre in Highgate.

I’ll be posting more on the production nearer the time, but all the when, where and hows are currently on the Theatre DaCapo website.

Link to details of Reminiscence play.

Recreational drug preference linked to medical speciality

Following our piece on several cases of drug addiction in anaesthetists, I just found some interesting studies on how recreational drug preference varies between medical specialities. It seems working in psychiatry and emergency medicine is linked to the highest rates of drug use, with surgeons having some of the lowest levels.

This study seems to be the most comprehensive on doctors of all levels of seniority:

Emergency medicine physicians used more illicit drugs. Psychiatrists used more benzodiazepines. Comparatively, pediatricians had overall low rates of use, as did surgeons, except for tobacco smoking. Anesthesiologists had higher use only for major opiates. Self-reported substance abuse and dependence were at highest levels among psychiatrists and emergency physicians, and lowest among surgeons. With evidence from studies such as this one, a specialty can organize prevention programs to address patterns of substance use specific to that specialty, the specialty characteristics of its members, and their unique practice environments that may contribute risk of substance abuse and dependence.

A 1992 study looked at exactly the same thing in junior doctors, and again found similar results – psychiatrists and emergency doctors tended to be more likely to use drugs, while surgeons were among the least likely:

Emergency medicine and psychiatry residents showed higher rates of substance use than residents in other specialties. Emergency medicine residents reported more current use of cocaine and marijuana, and psychiatry residents reported more current use of benzodiazepines and marijuana. Contrary to recent concerns, anesthesiology residents did not have high rates of substance use. Family/general practice, internal medicine, and obstetrics/gynecology were not among the higher or lower use groups for most substances. Surgeons had lower rates of substance use except for alcohol. Pediatric and pathology residents were least likely to be substance users.

A similar study on nurses was conducted by the same team a couple of years earlier and found similar results:

As hypothesized, rates varied greatly by speciality. Oncology nurses reported the highest past-year prevalence for all substances combined (42%), followed by psychiatry (40%) and emergency and adult critical care (both 38%).

Emergency and pediatric critical care nurses had the highest prevalence of marijuana / cocaine use (7%), followed by adult critical care nurses (6%). Prescription-type drug use was less varied across specialties: those with the highest prevalence of use were oncology, rehabilitation, and psychiatry. For cigarette smoking, psychiatry had the highest prevalence (23%), followed by emergency and gerontology (both 18%). Pediatric critical care nurses were least likely to smoke (8%). Binge drinking was high among oncology, emergency, and adult critical care nurses.

Link to abstract of recreational drug preference in doctors study.
Link to full text of drugs in junior doctors study.
Link to PubMed entry for same.
Link to full text of study on nurses.
Link to PubMed entry for same.

2008-08-08 Spike activity

Quick links from the past week in mind and brain news:

Language Log has an excellent piece on another reason why the amphetamine methylphenidate (Ritalin) may be popular as a study drug – apart from its boost to wakefulness it might actually improve some forms of learning.

Genes for schizophrenia uncovered. Again!

Scientific American reports on how our moral decision-making can be altered by distraction and additional cognitive effort.

Neurologist Robert Burton has a good piece in Salon on the placebo effect in conventional medicine.

Can cholesterol-lowering drugs reduce the risk of dementia? Newsweek examines evidence from a new study.

Furious Seasons on reports of people faking schizophrenia to get sleep-inducing antipsychotic drug quetiapine (Seroquel). God knows why.

US psychiatrists are deserting psychotherapy in favour of a sole focus on medication management, reports AP News. Original study here.

Edge presents A Short Course in Behavioural Economics. Scroll down past the chummy restaurant photos to get to the interesting bit.

Human brains have evolved a particularly strong capacity to detect what neuroscientists call ‚Äúerrors‚Äù. A sentence from a dreadful article on the ‘neuroscience’ ‘of’ ‘leadership’.

The New York Times discusses the benefits of boredom.

Researchers develop robots that learn to move themselves, reports BBC News. But the video shows they’re not just moving, they’re break dancing! Hey You The Robot Steady Crew, show em what you do, make a break, make a move.

Neuroanthropology has an excellent article on the sex differences and the ‘<a href="http://neuroanthropology.net/2008/08/07/girls-closing-math-gap-troubles-with-intelligence-1/
“>maths gap‘.

Daniel Dennett publishes an extract from his autobiography. No mention of inspiration for Santa-like beard yet.

Scientific American has an article on the neurological basis of genius.

The ‘torture debate‘ among US psychologists rumbles on and is covered by PsychCentral.

NPR Radio has an excellent piece on novelist Virginia Woolf and the psychology of the self, inspired by Jonah Lehrer’s recent book. Wonderfully produced in the unique RadioLab style.

Neuroscientist Shitij Kapur does the warm up for Gladys Knight with a lecture on dopamine and psychosis. No really. Channel N has the scoop.

Rolling thunder

Neurophilosophy covers the discovery of a new type of synaesthesia – where movement is experienced as sound. In fact, the researchers have put the test online so you can test yourself.

Synaesthesia is where the senses are ‘crossed’ so people might experience visual figures, such as letters, as tastes. This is one type, but letter to colour, sound to colour or number to space are most common.

This new study was initiated when the researchers were testing people with other forms who synaesthesia who happened to mention that they could ‘hear’ a moving pattern on a computer monitor.

Neurophilosophy picks up the story where the researchers sought to confirm this with an elegant experiment:

Saenz and Koch devised a task which could be used to objectively confirm the reports of the 4 participants, a task on which they would out-perform non-synaesthetes who do not experience the “extra” sensation. The task involved judging rhythmic patterns – in each trial, the participants were presented with pairs of sequences of either visual flashes or auditory beeps, and then asked if the two were the same.

Typically, non-synaesthetes are much better at judging auditory than visual sequences. But the hearing-motion synaesthetes should be at an advantage when presented with sequences of visual flashes, because they can hear, as well as see, the pattern. This is exactly what was found: the 4 synaesthetes and the 10 non-synaesthete controls performed equally well in the trials of sound sequences, with an accuracy of around 85%. But in the trials with sequences of visual flashes, the synaesthetes remained accurate, with a score of about 75%, whereas the performance of the controls fell to 50%, which is what would be expected by chance.

Link to Neurophilosophy on study.
Link to full text of study.