Nature NeuroPod visits SfN megaconference

Nature Neuroscience’s NeuroPod podcast has a special on the recent Society for Neuroscience annual megaconference that picks up on some of the more interesting new developments.

There’s loads of fascinating new findings in there, but don’t miss the last few minutes of the podcast where Prof Eleanor Maguire talks about ongoing work with London Taxi drivers.

Maguire’s team famously discovered in 2000 that London Taxi drivers have bigger than average hippocampi, a brain structure known to be heavily involved in learning routes and spatial representations.

The study found that the size of the hippocampus correlated with the length of time being a taxi driver, suggesting that the extensive training and navigational experience may change and develop the hippocampus.

The study won an Ig Nobel Prize in 2003 for research “that cannot, or should not, be reproduced” but was actually one of the first studies to show likely experience-related changes to the structure of the human brain.

In the podcast Maguire discusses a new study which updates the findings and suggests that the taxi drivers’ pumped hippocampi come at a cost.

While their navigational abilities were increased, their ability to learn new associations between things (another function of the hippocampus) was poor, and the size of the anterior hippocampi (a more forward area) was actually smaller.

This suggests that overdevelopment in one area of the hippocampus may actually reduce development in another.

mp3 of NeuroPod special at SfN 2007 conference.
Link to NeuroPod index page.
pdf of Eleanor Maguire’s Taxi driver update study.

Fighting over inner experience

Salon has an entertaining review of the new book Describing Inner Experience which is sort of a combination of an argument and a self-consciousness showdown between philosopher Eric Schwitzgebel and psychologist Russell Hurlburt.

Schwitzgebel is sceptical that we can accurately describe our inner thoughts and experiences, while Hurlburt feels that we are capable of doing so, when properly directed.

If you think that it’s obvious we can describe our inner mental states, start by reading the review and you’ll get a flavour of what the problem is.

At the beginning of the book’s central section, Hurlburt and Schwitzgebel meet their volunteer. Her pseudonym is Melanie. She is in her 20s, and she has an interest in psychology but no experience in these debates. Hurlburt explains the rules to her: She will simply tell them what was on her mind just before each beep, and they will try to figure out if her reports are accurate.

Hurlburt handles the direct questioning, then turns her over to Schwitzgebel for cross-examination. They have six sessions, each about an hour long. And over the course of these sessions, something unexpected happens, a novelistic twist that is subtle, hilarious and hard to describe. A battle for interpretive credibility emerges, as the doubt Schwitzgebel casts upon Melanie’s self-understanding rebounds upon himself.

The preface and first chapter of the book are freely available online if you want to learn more, and the book itself has just been published.

Link to Salon review.
Link to details of book and sample preface and chapter.

The art of first impressions

Frontal Cortex has found an absolutely fantastic video art piece that explores the psychology of first impressions.

It really brings home the fact that first impressions vary so much between individuals and can be vastly wide of the mark as character judgements.

The piece is by film-makers Lenka Clayton and James Price.

The pair also created the fantastic short film People in Order, another very simple premise which is a perceptive look at how people change as they age, and New Love Order, which briefly introduces us to couples arranged in the order of the length of their relationship.

All insightful pieces that are alternately, challenging, poignant, funny and original.

2008-01-11 Spike activity

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

A neuroimaging study on ESP! The Neurocritic looks at a recent study that investigated parapsychology using brain scanners.

Drug companies approximately spend $30 billion dollars promoting drugs in the US – twice as much as they spend on research and development, according to a new study in PLoS Medicine.

Scientific American reviews the year in robots. To the bunkers!

Sociologist Laura Maria Agustin argues that double standards in how we think about rich and poor people who cross borders is clouding the debate on ‘sex trafficking‘ in Reason magazine.

Harvard Magazine has an article on the genetics of autism and why the condition is being increasingly thought of a spectrum of traits rather than a cut-and-dry diagnosis.

Mirror Neurons – Rock Stars or Backup Singers? Neuroscientist Gregory Hickok argues against the mirror neuron hype on SciAm’s Mind Matters blog.

Professor of Robert Sylwester is interviewed on Sharp Brains on the cognitive science of learning.

Could a computers have a conscience? The Buffalo News ponders the possibilities.

PBS has a full programme and website on the debate over the increasing trend for medicating children with psychiatric drugs.

An article in Wired argues that the next victim of climate change will be our minds.

New hope for tinnitus sufferers as BBC News article discusses some new treatments in the pipeline.

Intelligence and working memory may be the key to identifying the genes for schizophrenia, suggests new research.

Furious Seasons has a careful analysis of one of the most important studies of treating depression yet completed.

How do we know we’re not dreaming? Eric Schwitzgebel looks at the possibilities.

Cognitive Daily has a fascinating article on whether your name affects your performance and preferences (something known as nominative determinism).

Cary Grant on LSD

Film star Cary Grant talks about his experiences with LSD in an excerpt from his autobiography.

Grant was one of the few people who were medically treated with LSD-assisted psychotherapy when it was still legal in 1960s America, and he claimed he benefited greatly from it.

The feeling is that of an unmarshaling of the thoughts as you’ve customarily associated them. The lessening of conscious control, similar to the mental process which takes place when we dream. For example, when you’re asleep and your mind no longer concerned with matters and activities of the day, your subconscious often brings itself to your attention by dreaming. With conscious controls relaxed, those thoughts buried deep inside begin to come to the surface in the form of dreams. These dreams, since they appear to us in symbolic guise, are fantasies and, if you will accept the reasoning, could be classified as hallucinations. Such fantasies, or hallucinations, are inside every one of us, waiting to be released, aired and understood. Dreams are really the emotions that we find ourselves reluctant to examine, think about, or meditate upon, while conscious.

Under the effect of LSD 25, these dreams or hallucinations, if you wish, are speeded up, and interpreted, when properly conducted ba a psychiatrically orientated doctor who sits quietly by, awaiting whatever communication one cares to make — the revealing of a hidden memory seen again from an older, more mature viewpoint, or the dawning of new enlightenment. Then, if the doctor is as skilled as mine was, he carefully proffers a word or key, that can lead to the next release, the next step toward fuller understanding.

Link to Grant on LSD, from his autobiography (via MeFi).

The psychology of the politics of fear

Newsweek has a fantastic article on the psychology and neuroscience behind the politics of fear which draws directly on examples from the current and past US elections.

American politics in particular it seems, has, in recent years, used fear as a way of trying to motivate voters and support particular candidates.

The Newsweek article looks at why fear is such a potent force in decision-making and what psychology research has shown us about how invoking concepts of death or threat actually affects our reasoning and desires.

“When we’re insecure, we want our leaders to have what’s called an ‘unconflicted personality’,” says political psychologist Jeff Greenberg of the University of Arizona. “Bush was very clear in his beliefs and had no doubts, but Kerry was painted as a flip-flopper…

That real-world observation has been replicated in lab studies. In one experiment Greenberg and colleagues ran during the 2004 campaign, volunteers who completed a questionnaire that reminded them about their own inevitable death (how thoughts of their own death made them feel and what they thought would happen to them physically after they died) expressed greater support for Bush than voters of similar leanings who were not reminded of mortality. The researchers also found that subliminal reminders of death increased support for Bush (and decreased support for Kerry) even among liberals. It’s not clear if such responses in the lab would endure in an actual voting booth. So perhaps one should not be too cynical about the decision by the Department of Homeland Security to raise the terror-threat level on Election Day 2004. “Political use of fear is not something new,” says NYU’s LeDoux. “But certainly the ante has been upped. We’ve gone from ‘vote for me or you’ll end up poor’ to ‘vote for me or you’ll end up dead’.”

Documentary maker Adam Curtis argued in his three-part series The Power of Nightmares (video: parts one, two, three) that since the cold war politicians across the globe have been attempting to promote the idea of foreign threats so they can then promise to deliver us from them.

Curtis is by no means a neutral commentator, but as he’s demonstrated with a number of his documentaries, his analysis of politics as an essentially psychological process is an interesting take on world affairs.

My only reservation about the Newsweek piece is that it takes the somewhat simplistic line that the amygdala equals fear in the brain.

The amygdala must have the worst PR of all of the brain structures, but to set the record straight, there’s more to the amygdala than fear, and more to fear than the amygdala.

Neurophilosophy has a guide to the neurobiology of fear if you want an overview of the wider fear circuits in the brain, and Current Biology has a freely available article which is a primer on the amygdala.

You may be interested to know that this almond shaped brain area is also involved in a range of positive emotional states, so it’s not all doom and gloom.

Link to Newsweek article ‘The Roots of Fear’ (via Schneier).

Opinion leaders impotent in ideas economy

Science News has a remarkably clear and concise article on a study that looked at how ideas spread through social networks. It found that under most circumstances a critical mass of more easily influenced people, not ‘opinion leaders’, are key to making ideas popular.

One of the major theories in marketing is that new ideas are taken up by the wider population because they are adopted by ‘opinion leaders’ – respected individuals who others listen to.

The theory goes that when opinion leaders adopt an idea, lots of other people quickly follow. Sort of like a ‘leader of the pack’ theory.

Researchers Duncan Watts and Peter Dodds wondered whether this was really the case, or whether instead, large numbers of people would embrace a particular idea when a certain number of their more easily influenced peers started to champion it. More of a ‘birds of a feather’ theory.

Watts and Dodds research how the mathematics of networks can tell us about how social systems work, and so they created various simulated social networks, set up some rules, and then ran the experiments to see how easily ideas would spread.

They simulated individual differences in the model by making each person more likely to adopt an idea if a certain percentage of their social network already believed it.

As some people are more easily influenced than others, the ‘people’ in the network varied in what percentage of their peers were needed to influence them – in effect, a mathematical simulation of individual scepticism.

The researchers compared how far an idea would spread depending on whether it started with a random individual or with an influential individual who was connected to a lot of other individuals. They found that highly influential individuals usually spread ideas more widely, but not very much more widely. For example, if an individual had three times as many connections as the average person, ideas espoused by that individual almost always spread substantially less than three times as far as the ideas of an average individual. Sometimes, the researchers found, the difference wasn’t even measurable…

More important than the influencers, the researchers found, were the influenced. Once an idea spread to a critical mass of easily influenced individuals, it took hold and continued to spread to other easily influenced individuals. In some networks, it was far easier to get an idea established this way than in others. The entire structure of the network mattered, not just the few influential people.

The full-text of Watts and Dodds’ paper is available online as a pdf if you want to read the study in more detail, but the Science News article is a great summary.

Link to Science News on ‘The Power of Being Influenced’.
pdf of study ‘Influentials, Networks, and Public Opinion Formation’.

‘Stress’: from buildings to the battlefield

Sometimes we don’t realise how much the vocabulary of psychology has become part of everyday language.

I was surprised to learn that the use of the term ‘stress’ to mean psychological tension, rather than just physical pressure, has only been with us since the mid-1930s and was popularised by the major wars of the 20th century.

And it turns out, the person who coined the new usage did it by accident, owing to a mistaken translation.

Akin to ‘distress’, ‘stress’ meant ‘a strain upon endurance’, but it was also used in a more specialist way by engineers to denote the external pressures on a structure – the effects of ‘stress’ within the structure became known as ‘strain’.

Then in 1935 the Czech-Candian physiologist Hans Selye began to promote ‘stress’ as a medical term, denoting the body’s response to external pressures (he later admitted that, new to the English language, he had picked the wrong word; ‘strain’ was what he had meant).

Academic physiologists regarded the concept of stress as too vague to be scientifically useful, but Selye’s determined self-promotion, coupled with the upheaval and distress brought by the [Second World] war to many millions of ordinary people, popularised the term.

By the time of Vietnam, ‘stress’ had become a well-established part of military medicine, thought to be a valuble tool in reducing ‘wastage’. In the military context, it was an extension of the work done at the end of the First World War on the long-term effects of fear and other emotions on the human system…

‘Stress’, writes the historian Russell Viner, ‘was pictured as a weapon, to be used in the waging of psychological warfare against the enemy, and Stress research as a sheild or vaccination against the contagious germ of fear.’

From p349 of A War of Nerves, a book on the history of military psychiatry, which we covered previously.

A phobia of bridges

The New York Times has a short but interesting piece on people with gephyrophobia, a morbid fear of bridges.

Phobias are often described as an irrational fear, but most have a reasonable basis to them, as reflected in the fact that phobias most commonly concern things that have an element of danger or risk – such as heights, dogs, spiders or water.

However, the fear gets exaggerated so the perceived danger vastly outweighs the actual danger.

Often the disabling aspect is not the fear itself, but how people begin to restrict their lives to avoid the fear. In a sense, people can become driven by a fear of fear.

Mrs. Steers, 47, suffered from a little-known disorder called gephyrophobia, a fear of bridges. And she had the misfortune of living in a region with 26 major bridges, whose heights and spans could turn an afternoon car ride into a rolling trip through a haunted house.

Some people go miles out of their way to avoid crossing the George Washington Bridge — for example, driving to Upper Manhattan from Teaneck, N.J., by way of the Lincoln Tunnel, a detour that can stretch a 19-minute jog into a three-quarter-hour ordeal. Other bridge phobics recite baby names or play the radio loudly as they ease onto a nerve-jangling span — anything to focus the mind. Still others take a mild tranquilizer an hour before buckling up to cross a bridge.

Link to NYT article ‘To Gephyrophobiacs, Bridges Are a Terror’.

Composing, by brain waves

Mick Grierson has been hacking some applications for a brain-computer interface that uses EEG to convert the brain’s electrical signals into a thought-driven synthesizer control mechanism.

The kit is just in a test stage at the moment, but there’s a YouTube video of him being able to trigger specific notes from his EEG signals.

OK. So I’ve had my EEG for about a month now. Within a few days, I’d successfully run a project that allowed me to spell words with my thoughts. This took some practice, and the algorithms are really elementary at the moment. However, it’s nice to be on the edge of what is possible. I’ve just spent a few days integrating a fairly obvious matching algorithm Рbasically an algorithm that detects unconscious responses to stimuli on a simple level Рinto a synthesiser built in max/msp. This took quite a lot of effort. Anyhow, this system is a variation of those which you may have been hearing about on and off….my system now allows me (with a bit of work) to control the pitch of the synthesiser with my thoughts in real-time. This reliably allows me to play tunes Рslowly. I often ‘hit’ wrong notes, but it sort of works. Has anyone else done this yet?

Can’t wait to see how the project advances. The first jam session will be quite a sight (and sound!), I’m sure.

Link to video of BCI synthesiser (via DevIntel).
Link to Grierson’s blog.

Knock, knock, room service

NPR has a short piece on a fascinating study where the researchers informed hotel maids that their normal work counted as exercise, which had the effect of making them more physically fit, despite them not seeming to change their activity levels.

Unfortunately, the NPR segment seems to suggest that the study ‘challenges the placebo effect’, based on the faulty assumption that the placebo effect only alters ‘subjective perception’.

In fact, placebos are known to affect outcome in a range of physical illnesses (and even produce placebo ‘side-effects – known as the nocebo effect), and they have been shown to directly stimulate the same brain circuit when they are used to replace a drug to treat Parkinson’s disease.

Furthermore, the study itself [pdf] claims to demonstrate the placebo effect in a new domain.

Despite this, it’s a fascinating study and raises a number of intriguing questions, such as whether the placebo effect is directly affecting body metabolism, or whether the information given to the maids just made them behave differently, and actually do their work in a way to give more health benefits.

Link to NPR piece on the study.
pdf of full-text of study.

Buy your own brain surgery tools, online

I’ve just found a page with some beautiful pictures of antique neurosurgery tools, including these trephining or trepanning tools for cutting holes in the skull. Can you imagine the elbow work needed to get the job done?

After a bit of a search I discovered that there’s a healthy market in neurosurgical tools on the net, old and new.

Advances in the History of Psychology discovered an antique trepanning brace that’s currently for sale for a cool $1900.

One antique dealer even has a receipt for a trepanning operation from 1814. It turns out you could get your head drilled for $20 in early 19th century Massachusetts.

If you’re after some more modern kit, it turns out you can pick up quite a few contemporary surgical tools on eBay.

Including this VectorVision2 BrainLab system, a snip (excuse the pun) at $15,000.

The VectorVision2 is an ‘augmented reality’ image guidance system (sometimes called frameless stereotaxy) that allows the surgeon to see where his tools are in relation to both the patient and a matched brain scan image – while the operation is in progress.

While the tools can be bought and sold online, most of the anaesthetics are, of course, controlled drugs.

So while you may be able to get the latest high-tech kit on eBay, you’re still going to have to resort to those traditional 19th century surgical painkillers: brandy, and a stiff upper lip.

Link to pictures of antique neurosurgery tools.
Link to VectorVision2 for sale on eBay.

Castration anxiety, of a non-Freudian kind

This interesting study published in Perspectives in Biology and Medicine compared the psychological effect of castration on two quite different groups of people: on people with prostrate cancer for whom the procedure was a medical necessity, and for people who wished to castrate themselves on a voluntary basis.

Motivations for voluntary eunuchs vary, but in certain forms the condition is thought to be related to apotemnophilia or ‘body integrity identity disorder’ – where individuals have a pathological desire to have a limb amputated, often taking quite severe and damaging measures to achieve their aim.

However, eunuchs have had a long and complex social and symbolic role in history that belies the simple fact of the operation.

In fact, there is quite a large online eunuch community, who share an interest in the procedure, whether they’re personally motivated to have it, or whether they’re just interested in it for, well, whatever reason sparks your interest I suppose.

Modern-day eunuchs: motivations for and consequences of contemporary castration.

Perspect Biol Med. 2007, 50(4), 544-56.

Wassersug RJ, Johnson TW.

This article compares the motivations for, and responses to, castration between two groups of males: prostate cancer patients and voluntary modern-day eunuchs with castration paraphilias or other emasculating obsessions. Prostate cancer patients are distressed by the side effects of androgen deprivation and typically strive to hide or deny the effects of castration. In contrast, most voluntary eunuchs are pleased with the results of their emasculations. Despite a suggested association of androgen deprivation with depression, voluntary eunuchs appear to function well, both psychologically and socially. Motivation, rather than physiology, appears to account for these different responses to androgen deprivation.

Probably not quite the literal form of castration anxiety Freud had in mind when he invented the psychoanalytic term.

Link to abstract of study on PubMed.

Milgram’s notorious conformity experiment replicated

The Situationist has a fantastic post on a recent replication of Stanley Milgram’s (in)famous conformity experiment which is usually always described as being ‘too unethical to perform today’.

In Milgram’s original study, participants were asked to give increasingly severe electric shocks to someone supposedly trying to learn a series of word pairs.

In fact, the ‘learner’ was an actor and no shocks were given, but they screamed as if they were in increasing amounts of pain, while the experimenter ordered the participant to increase the voltage.

The experiment tested how far someone would go in giving pain to another human being when being ordered by an authority figure. 65% of participants continued despite indications that the ‘learner’ might be unconscious or dead.

It’s been a hugely influential study, but was thought to be so stressful for the participants, that it has never been replicated in real life and it was assumed it would be impossible to do so.

However, this replication was carefully designed by Prof Jerry Burger to be as close as possible to Milgram’s original study while being modified so it could be fully ethically approved by a research ethics committee (the mark of all good research).

I went to great lengths to recreate Milgram’s procedures (Experiment Five), including such details as the words used in the memory test and the experimenter’s lab coat. But I also made several substantial changes.

First, we stopped the procedures at the 150-volt mark. This is the first time participants heard the learner’s protests through the wall and his demands to be released. When we look at Milgram’s data, we find that this point in the procedure is something of a “point of no return.” Of the participants who continued past 150 volts, 79 percent went all the way to the highest level of the shock generator (450 volts). Knowing how people respond up to this point allowed us to make a reasonable estimate of what they would do if allowed to continue to the end. Stopping the study at this juncture also avoided exposing participants to the intense stress Milgram’s participants often experienced in the subsequent parts of the procedure.

Second, we used a two-step screening process for potential participants to exclude any individuals who might have a negative reaction to the experience. . . . More than 38 percent of the interviewed participants were excluded at this point.

Third, participants were told at least three times (twice in writing) that they could withdraw from the study at any time and still receive their $50 for participation.

Fourth, like Milgram, we administered a sample shock to our participants (with their consent). However, we administered a very mild 15-volt shock rather than the 45-volt shock Milgram gave his participants.

Fifth, we allowed virtually no time to elapse between ending the session and informing participants that the learner had received no shocks. Within a few seconds after ending the study, the learner entered the room to reassure the participant he was fine. Sixth, the experimenter who ran the study also was a clinical psychologist who was instructed to end the session immediately if he saw any signs of excessive stress.

Although each of these safeguards came with a methodological price (e.g., the potential effect of screening out certain individuals, the effect of emphasizing that participants could leave at any time), I wanted to take every reasonable measure to ensure that our participants were treated in a humane and ethical manner.

Interestingly, the study found that levels of obedience were about the same now, as they were in the early 1960s when the original experiment was first run.

This is not the first time that someone has tried to replicate Milgram’s experiment. The BPS Research Digest reported on a virtual reality version of the study (admittedly, not a true replication), the full-text of which is available online.

The Situationist post also includes a embedded video of a TV documentary on the replication and notes some disturbing examples where the experiment has been inadvertently replicated when a prank caller directed staff to give shock to two emotionally disturbed teenagers.

Link to Situationist on Milgram replication (thanks Tom!)
Link to Wikipedia page on Milgram’s original study.

17th century brain surgery, digitally recreated

A reader of neuroscience blog Retrospectacle wrote in to say they’d created a video simulation of how a 17th century brain surgery tool would work, and it’s a wonderfully vivid, if not somewhat gruesome, animation of the tool in action.

The tool was the elevatorium biploidum and was described by the pioneering Dutch surgeon Cornelius Solingen in his book Manuale Operatien der Chirurgie.

Boerhaave Museum describes the use of the tool:

Bullets from seventeenth-century guns had slightly less velocity than the bullets of today. The damage they caused, particularly if you were hit in the head, was consequently sometimes less serious than might have been expected. Not every bullet penetrated the skull, but they often left a sizeable dent. Under the dent there might be haemorrhaging, because of the rupturing of local blood vessel as a result of the impact. In order to treat that bleeding and the associated pressure on the brain the Hague surgeon Cornelis Solingen (1641-1687) has developed a sort of ‘corkscrew’, with which you could raise the dented cranium again.

The tool obviously had (if you’ll excuse the pun) quite an impact at the time as it is featured on the front page of the museum’s website. Indeed, similar surgical techniques are still in use today.

Link to video animation of the elevatorium biploidum.
Link to Retrospectacle post.
Link to Boerhaave Museum page on the tool.

Dreamy panic mashup

ABC Radio National’s All in the Mind recently broadcast a beautifully produced edition on the cultural history of panic.

Curiously, it inspired a student of one of the sociologists interviewed on the programme to create their own retro video mashup using some of the audio.

It’s a wonderfully atmospheric, dreamily paranoid and a striking accompaniment to the programme.

Whoever thought panic could feel so ambient?

Link to AITM on a cultural history of panic.
Link to video of dreamy panic video (via AITM blog).