Being Human

I'm just reading a long but gripping study that used social network analysis to look at murder as a social interaction between gangs in Chicago to understand how stable networks of retaliation are sustained over time.

However, I was struck by this bit in the introduction, which really highlights the social nature of murder:

But we know that murder is not in fact such a random matter. It is first and foremost an interaction between two people who more often than not know each other: approximately 75% of all homicides in the United States from 1995 to 2002 occurred between people who knew each other prior to the murder (Federal Bureau of Investigation, selected years).

We also know that the victim and offender tend to resemble each other socially and demographically (e.g., Wolfgang 1958; Luckenbill 1977). Young people kill other young people, poor people kill other poor people, gang members kill other gang members, and so on. Thus, contrary to stratification theories, a particular murder is not so much the outcome of the differential distribution of attributes as it is an interaction governed by patterns of social relations between people similar in stature and status.

It's an amazing paper which combines a social network analysis drawn from police murder records with field work that involved talking to gang members to understand their perception and use of violence.

Link to PubMed entry for 'Murder by structure'.
Link to DOI entry for same.

I just found a some curious case reports on two people who had hallucinations in everyday life owing to unrecognised narcolepsy, but not realising it, they assumed their hallucinated episodes had genuinely occurred.

Unlike in psychosis, where affected people often believe that their hallucinations are real, people who have narcolepsy and have hallucinations are usually able to realise they were triggered by the condition.

In this case, the people were unaware that they had a tendency to hallucinate and so the boundaries between hallucination and reality began to blur.

The 45-year-old technical manager had a multi-year history of daytime sleepiness... He frequently had curious experiences during the day – the neighbour throwing litter into the patient's bin; his wife throwing precious objects away. Sometimes he saw himself trying to clean dirt on the side of a ditch. These memories and experiences were confusing. They gave rise to a surprised and suspicious state of mind.

Improbable and incomprehensible things happened, leaving him in doubt. Sometimes he gave sensitive-paranoid interpretations to the events, he also denounced the neighbour for filling his bin. His paranoidity drove his psychiatrist to the diagnostic conclusion of a delusional psychosis.

Recently he had a severe conflict with his chief on account of a vivid experience of having had sexual intercourse with the chief's wife, which he mentioned to colleagues. Remembering every detail, he was convinced that his story was true, but the reactions of those around him gradually convinced him that this experience could be a hallucination.

The man was eventually referred to a sleep clinic, diagnosed with narcolepsy and successfully treated.

The other case is of a young woman who hallucinated that she had been sexually assaulted on a bus - an experience so vivid that she reported it to the police with numerous details of the offender.

She later realised that that she could have been wrong and as part of the court case for making a false police report she was medically assessed and also diagnosed with narcolepsy after a sleep lab assessment.

Link to PubMed entry for case reports.

Today's Nature has an excellent piece about an increasing and currently not well-researched trend for fMRI brain scan 'neurofeedback' treatments, where the patient is shown a visual representation of the activity of a certain brain area in the hope of learning to control it.

In this case, the big idea is that a patient with chronic pain is shown real-time activity in their anterior cingulate cortex, an area in the frontal lobe associated with the 'unpleasantness' of pain (rather than just its physical sensation), and they can see when they doing something to successfully reduce the activity and can try and learn to do it reliably.

The article looks at the work of Sean Mackey who researches the area but is appropriately skeptical about a number of companies who have recently sprung up offering this as a treatment, despite the lack of firm evidence.

As you may recall, this premature commercialisation is a bit of a pattern with fMRI research, as you can also buy the services of companies offering 'lie detection' and 'neuromarketing' despite a similar lack of evidence for their usefulness.

However, the piece also looks more generally at the neuroscience of pain which is, if you'll excuse the pun, becoming a hot area, both as the understanding of pain moves away from the idea that it happens 'in the body' to the idea that it is handled by numerous brain circuits, each which may be involved if different aspects of the experience and our behavioural reaction to it.

In some of his other work, Mackey's laboratory has used fMRI to explore these connections between pain processing and cognitive processes. Fear of pain, for example, can increase the pain itself, and Mackey's group studied some of the brain regions involved in this anticipation. In another study he showed that watching someone else in pain activates brain areas that are fairly distinct from those active during one's own pain. And in unpublished work he has found that romantic love can lessen the experience of pain. Mackey says these connections demonstrate how strong an influence conscious thought may have over pain processing.

Link to Nature article 'Shooting pain'.

A fantastic study just published in Cognition reports that the motion aftereffect illusion, where staring at something constantly moving in one direction causes illusory movement in the opposite direction when you look away, can be caused just by imagining that the movement is happening.

The effect is occasionally called the 'waterfall illusion' because it can be triggered by staring at a waterfall for a few minutes and then looking at the nearby bank, which will seem as if it is moving upward, in the opposite direction to the falling water.

It was traditionally explained by the fact that direction-specific motion-detecting neurons in the brain's visual areas 'habituate' or adapt to constant movement by slowly becoming less active, as if they barely need to keep reporting with the same vigour because they're just detecting more of the same.

According to this explanation, when you look away, these 'habituated' neurons are caught off guard and the neurons that look out for motion in the opposite direction are relatively stronger and so, until the balance is readdressed, give the impression that the world is moving contrary to your past experience.

As with most of these things, it turns out not to be quite so simple, but the effect is so easily invoked that it is used widely in vision and motion research.

One of the key findings in this area is that visual imagery activates some of the same areas as actually seeing what you're thinking of. In other words, the brain seems to simulate the visual experience actually in the visual system.

Or at least, that's what it looks like from the brain scans, but just because the same areas are active during both tasks, it doesn't mean the same neurons are being used. It could be completely different processes at work that just happen to share the same neural office space.

So here's the cool bit. This new study, led by psychologist Jonathan Winawer, asked participants to briefly view a moving pattern. It only appeared briefly, not long enough to cause the effect, and then disappeared.

Then were then shown the same pattern, without any movement, and were asked to imagine that it was moving in the same way. After a short while, the pattern was replaced by a picture of motionless dots, and they were asked to indicate if they saw the dots moving in a particular direction.

If the effect appeared, participants should see the dots moving in the opposite direction.

The participants were asked to imagine different directions and types of motion and then were given the same task but where they didn't need to imagine anything, as the pattern moved by itself.

As expected, the moving pattern caused a clear motion aftereffect, but rather wonderfully, the effect appeared after participants had simply imagined the movement. It wasn't as strong but it was clearly there.

They researchers also asked the participants after which direction would they expect the dots to go in, to check they hadn't heard about the effect or were just doing what they thought was expected of them, and they couldn't reliably give the correct direction that the effect would cause.

This provides good evidence that when imagine visual experiences we're actually running a simulation in the same parts of the brain that are used to actually see the world.

Link to PubMed entry for study.
pdf of full text paper.

n+1 has an excellent article on how neuroscience is making an increasing appearance in novels, not only as a subject, but also as a literary device to explore characters and explain their motivations.

It marks the start of the trend from Ian McEwan’s Enduring Love and notes that in more recent years books such as Richard Powers’s The Echomaker, Mark Haddon’s Curious Incident of the Dog in the Night-Time and Rivka Galchen's Atmospheric Disturbances have all drawn heavily from the medical and brain science literature for their main hooks.

What makes so many writers try their hands and brains at the neuronovel? At the most obvious level, the trend follows a cultural (and, in psychology proper, a disciplinary) shift away from environmental and relational theories of personality back to the study of brains themselves, as the source of who we are. This cultural sea change probably began with the exhaustion of “the linguistic turn” in the humanities, in the 1980s, and with the discredit psychoanalysis suffered, around the same time, from revelations that Freud had discounted some credible claims of sexual abuse among his patients. Those philosophers of mind who had always been opposed to trendy French poststructuralism or old-fashioned Freudianism, and the mutability of personality these implied, put forth strong claims for the persistence of innate ideas and unalterable structures.

And in neuroscience such changes as the mind did endure were analyzed in terms of chemistry. By the early ’90s, psychoanalysis—whether of a Lacanian and therefore linguistic variety, or a Freudian and drive-oriented kind—was generally considered bankrupt, not to mention far less effective and more expensive than the psychiatric drugs (like Prozac) that began to flow through the general population’s bloodstream. The new reductionism of mind to brain, eagerly taken up by the press—especially the New York Times in its science pages—had two main properties: it explained proximate causes of mental function in terms of neurochemistry, and ultimate causes in terms of evolution and heredity.

It's really well researched piece and neatly outlines the play between literature, science writing, culture and neuroscience through the development of numerous popular novels in the area.

Link to n+1 article 'The Rise of the Neuronovel'.

The Neurocritic has compiled a collection of interesting neurological studies where a number of patients seems to have experienced a profound change in their sexual preferences as a result of brain disturbance.

One of the most well-known of these studies is a recent case of a man who was convicted of paedophilia late in life, but was later found to have a brain tumour, and on removal of the tumour his sudden interest in children disappeared. It reappeared again when the tumour once more began to grow.

The case has raised questions about free will and self-determination in light of the fact that such morally reprehensible acts seemed only to occur when a tumour was affecting brain function.

It's importantly to mention that brain damage rarely causes such tragic events, although sexual difficulties, in general, are not uncommon. Problems can range from difficulties with arousal and enjoyment, to behavioural disturbances and inappropriate behaviour.

In some rare cases, preferences themselves seem to be affected, although it's never clear whether it's actually that the person has different desires, or whether they always had them but now are, perhaps, less able to stop themselves acting on them.

It's easier to think that damage has changed people's desires when the behaviour markedly unusual, such as this case of a man who was, to put it bluntly, screwing the coin return tray of a public telephone after brain deterioration.

But one thing we know from the forensic literature and cases of healthy people who accidentally die during sexual practices (for example, these two), is that no matter how strange the attraction seems to you, someone is out there expressing it.

Not all of the cases of changes sexuality after brain damage are where people act outside of the norm, of course. In one, admittedly, not brilliantly detailed case, an apparently exclusively homosexual man found he developed heterosexual attraction after a stroke.

Sadly, this area is massively under-researched so we really know relatively little about how different aspects of desire, emotional attachment and sexual behaviour are handled by the brain, but these case studies give us a window into the possibilities.

Link to The Neurocritic on 'Unusual Changes in Sexuality'.

I've just discovered a curious medical finding that can be detected on MRI brain scans called the 'face of the giant panda sign' where, quite literally, it looks like there's a panda face in the middle of the brain, indicating a specific pattern of neural damage.

The image you can see on the left is the 'face of the giant panda sign' that appeared in a brain scan of a patient with multiple sclerosis who started showing unusual sexual behaviour and is taken from a 2002 study. Click the image if you want to see the whole scan.

The pattern is apparently caused by "high signal in the tegmentum, normal signals in the red nuclei and lateral portion of the pars reticulata of the substantia nigra, and hypointensity of the superior colliculus".

It is most associated with Wilson's disease, a genetic condition which causes a toxic build-up of copper in the body, but obviously can appear in other disorders as well.

Thanks to Twitter user @sarcastic_f for alerting me to this.

It's not just pandas that appear in brain scans of course, the Virgin Mary has also been known to make an appearance.

Link to PubMed entry for MS study.
Link to brief description from Neurology.

While strolling through town the other day, I came across this fantastic memory and brain-themed poster.

It's from the University of Antioquia's museum who are holding an art and literature competition to celebrate 200 years of Colombian independence.

Click the image for a bigger version or hit the link below if you want to see it in all its glory.

Link to bigger version.

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

The single best article you'll read on technology and the brain for a while is published in The Times. 300 words of sense.

The Sydney Morning Herald covers an inattentional blindness study in mobile phone users and asks 'Did you see that unicycling clown?' I'm more interested to know whether the unicycling clown saw the psychologist following him around all day.

Apart from the fact that she seems to be labouring under the misapprehension that the right temporal parietal junction is not used for anything else (it is) there's an excellent TED talk by Rebecca Saxe on 'theory of mind' and the neuroscience of inferring others' mental states.

Neurophilosophy covers on how electrodes planted into the open brain of an awake patient reveals the neural dynamics of speech. Accompanied by an equally as awesome image.

The anthropology song is featured on Neuroanthropology.

The Neurocritic finds an intriguing film about a professor who believes she has found a way of determining scientifically whether someone is in love.

Philosopher Stephen Stich gives four lectures on 'Moral Theory Meets Cognitive Science' which are collected at 3 Quarks Daily.

Dr Petra has been upgraded!

Another good TED talk, this time by Beau Lotto on what optical illusions tell us about perception.

Science News on research that a gene involved in vocal cord development may be a factor in a inherited speech disorder.

There's a brief Q&A on the science of persuasion over at Nature.

The BPS Research Digest covers some heart-warming research on how a heated room makes people feel socially closer.

You can read a free taster issue of November's The Psychologist here. Enjoy!

Scientific American's Mind Matters blog has a great piece on making errors and learning.

Another good Neurophilosophy post, on how immediate goal kicking performance in American 'foot' 'ball' affects the perception of how big the goal seems.

Science News reports that 'People can control their Halle Berry neurons'. Neurons? I have enough trouble trying to control my Halle Berry thoughts. Don't think of Catwoman. Damn.

The National Alliance on Mental Illness (NAMI) is an American nonprofit, grassroots, self-help, support and advocacy organization of consumers, families, and friends of people with severe mental illnesses that happens to receive 75% of its funding from Big Pharma, according to The New York Times.

Cognitive Daily asks What does it take to get kids to eat healthy foods? Personally, I bribe them with cans of Red Bull.

There's on excellent piece on how antidepressant sales are rising despite depression diagnoses falling in the UK over at Neuroskeptic. Apparently, longer-term treatment is now the norm.

FAILBlog has a hilarious duck phobia fail.

To the bunkers! H+ Magazine reports on robots controlled by human brain cells. Let's hope they're not the Halle Berry neurons.

Slashdot commentor kindly lists all the Doctor Who references to robots controlled by organic brains.

I found this great article on drug counterfeiting from a 1961 edition of Popular Mechanics.

BoingBoing has an interesting snippet on a new NIH study which will deploy robo-calling for boozers and stoners. Press 1 if you're taking a bong hit?

Happy belated Fechner Day.

Language Log asks 'Is irony universal?'. Rather ironically, asked by Americans. Also some interesting observations in the comments from Danny O'Brien.

Insecurity + power = boss rage, according to a new study covered by Neuronarrative.

The New York Times has a piece by David Brooks who marvels at how "damned young, hip and attractive" neuroscientists are. I would just like to disavow this dreadful stereotyping and point out that, like myself, many competent neuroscientists look pretty rough and find being deeply unfashionable quite groovy (by still using words like 'groovy' for example).

We often think that pressure on young women to be thin is a modern phenomenon, but a fascinating letter to the Journal of the American Academy of Child and Adolescent Psychiatry published in 2000 noted that this is not a new development. The authors cite evidence from Ancient Rome showing a similar cultural pressures were widespread:

Garner et al. (1985) wrote about the present “unprecedented emphasis on thinness and dieting” which is one factor responsible for the increase in anorexic and bulimic disorders. It is generally believed that dieting in pursuit of a thinner shape and slimness as a standard for feminine beauty are modern attitudes. However, a clear account can be found in the ancient comedy Terence’s Eunuchus.

Terence (Publius Terentius Afer) (c. 190–159 BC) was a Roman comic poet. His 6 surviving comedies are Greek in origin but describe the contemporary Roman society. Eunuchus was probably presented in 161 BC. In this comedy, a young man named Chaerea declares his love for a 16-year-old girl whom he depicts as looking different from other girls and he protests against the contemporary emphasis on thinness: “haud similis uirgost uirginum nostrarum quas matres student demissis umeris esse, uincto pectore, ut gracilae sient. si quaest habitior paullo, pugilem esse aiunt, deducunt cibum; tam etsi bonast natura, reddunt curatura iunceam. itaque ergo amantur.” (She is a girl who doesn’t look like the girls of our day whose mothers strive to make them have sloping shoulders, a squeezed chest so that they look slim. If one is a little plumper, they say she is a boxer and they reduce her diet. Though she is well endowed by nature, this treatment makes her as thin as a bulrush. And men love them for that!) Then he describes the girl he loves: “noua figura oris . . . color uerus, corpus solidum et suci plenum” (unusual looks . . . a natural complexion, a plump and firm body, full of vitality). So he opposes vividly the typical thinness of the girls of these times to the blossomed body of the girl he loves.

This Roman pressure on girls to diet to meet the social expectations for thinness represents a clear precedent for the current emphasis on thinness. It is clear that in Ancient Rome, as in today’s society, there were multiple factors related to the development of body image concerns which today are often a precursor to eating disorders. These include cultural pressures to strive to develop and maintain a particular body shape in order to be considered attractive and then valued as a woman. Here, Terence mentions Chaerea’s preference for a plumper girl, while mothers usually wished their daughters to be thinner. Although the media influences that today are critical in influencing images of a perfect body were not present in Ancient Rome, it is clear from this part of the text that pressures concerning appearance existed long before the 20th century.

Link to PubMed entry for letter.

New Scientist has an excellent article on how the brain makes sense of time and looks at why certain intense experiences seem to trigger the perception that time has slowed down.

It covers David Eagleman's well-known study where he dropped people 30 metres into a safety net and while falling, asked them to read off numbers that were flashing by too fast for normal perception.

The idea was that if time really did 'slow down', or rather, if the brain became 'over-clocked' and the resolution of time perception genuinely became more fine-grained, the participants could read off some of the digits that they couldn't normally make sense of. As it happened, they couldn't, suggesting that time slowing effect is an illusion and not an effect of the brain going into overdrive.

The piece also has an interesting discussion of how cognitive scientists are using the wagon wheel effect to study time perception in the brain. This is where after a certain speed, spokes on a wheel seem to starting moving backward.

This has been used to work out the brain's 'refresh rate', but it turns out that this is unlikely to be a global process because when looking at two such objects moving at exactly the same rate, only one of them might be subject to the effect.

This suggests that the brain might have many clocks, perhaps each assigned to a different task:

The case for discrete perception is far from closed, however. When Eagleman showed subjects a pair of overlapping patterns, both moving at the same rate, they often saw one pattern reverse independently of the other. "If you were taking frames of the world, then everything would have to reverse at the same time," says Eagleman.

VanRullen has an alternative explanation. The brain processes different objects within the visual field independently of one another, even if they overlap in space, he suggests. So the RPL [right inferior parietal lobe] may well be taking the "snapshots" of the two moving patterns at separate instances - and possibly at slightly different rates - making it plausible that the illusions could happen independently for each object.

This implies that there is not a single "film roll" in the brain, but many separate streams, each recording a separate piece of information. What's more, this way of dealing with incoming information may not apply solely to motion perception. Other brain processes, such as object or sound recognition, might also be processed as discrete packets.

Link to NewSci piece 'Timewarp'.

One of the most famous and most mythologised studies in psychology concerns John Watson's experiment to condition 'Little Albert' to be afraid of a white rat. 'Little Albert' and his mother moved away afterwards and no-one knew what happened to him, leading to one of the most enduring mysteries in psychology. Finally, it seems, his identity has been discovered.

An article in the latest edition of American Psychologist recounts a detective story, led by psychologist Hall Beck, to try and solve the question of what happened to 'Little Albert' after his participation in the famous study.

The experiment itself consisted of showing the infant some live animals, most notably a white rat, and some other assorted objects, to demonstrate he had no pre-existing fear of them.

On several later occasions, when playing happily with the white rat, Watson and his colleague Rosalie Rayner struck a metal bar to frighten the young child. Subsequently, simply seeing the rat was enough to cause Albert to cry and show visible distress - demonstrating the phenomenon of classical conditioning, where something previously neutral can be associated with the responses triggered by something else.

Although accounts vary, Albert may have shown generalisation of his learnt response, so he became distressed at things like rabbits, dogs and furry coats, despite the fact that experimenters never presented these with a frightening noise.

'Little Albert' and his mother moved away from the university, his identity was lost and for years psychologists and historians have wondered what happened to the unwilling star in one of the landmark studies of the 20th century.

The first step was to find out exactly when the experiments took place and then to try and identify Albert's mother from the information given in Watson's original studies.

Careful sifting of financial and residency records put the researchers onto a campus wet nurse called Arvilla Merritte, but there the trail went cold.

There were no others traces of Arvilla Merritte but a search for her maiden name, Arvilla Irons, revealed that her married name was likely fictitious to hide the fact that her baby was illegitimate.

However, Irons' baby was not called Albert, but Douglas, and it wasn't until the Irons family got in touch to send a photo of the baby that the researchers could try and make a physical comparison.

The photos were blurry and they recruited the help of an FBI forensics expert to compare the images. The comparison suggested that the photos were likely of the same person and with the other matching biographical details it seems very likely that Douglas Merritte was indeed 'Little Albert'.

The story has a tragic ending, however, as Douglas Merritte died when only six years old after developing hydrocephalus, a build up of fluid in the brain, possibly due to a meningitis infection.

Beck finishes the article on a melancholy note, reflecting on his own part in the story, Little Albert's short life and his visit to his grave:

As I watched Gary and Helen put flowers on the grave, I recalled a daydream in which I had envisioned showing a puzzled old man Watson’s film of him as a baby. My small fantasy was among the dozens of misconceptions and myths inspired by Douglas.

"The sunbeam’s smile, the zephyr’s breath,
All that it knew from birth to death."

None of the folktales we encountered during our inquiry had a factual basis. There is no evidence that the baby’s mother was “outraged” at her son’s treatment or that Douglas’s phobia proved resistant to extinction. Douglas was never deconditioned, and he was not adopted by a family north of Baltimore.

Nor was he ever an old man. Our search of seven years was longer than the little boy’s life. I laid flowers on the grave of my longtime “companion,” turned, and simultaneously felt a great peace and profound loneliness.

Link to summary of article in American Psychologist.

ABC Radio National's All in the Mind has a powerful and moving programme on the experience of 'hearing voices' that meets with two young women with quite different experiences of auditory hallucinations.

One of the young women, Kat, has largely positive voices and has come to understand and work with them, while another, Mel, has an abusive and taunting voice that has clearly caused a huge amount of distress and impairment.

Mel's story is difficult to hear in parts and the programme starkly illustrates the range of experiences that accompany auditory hallucinations.

The piece also tackles current ideas and approaches to 'hearing voices', from the medical and scientific to the grassroots and social approach of the Hearing Voices Network.

There's also an equally powerful video interview on the AITM site at the link below.

Link to AITM on 'Hearing Voices: stories from the coalface'.

Technology Review has a fantastic photo essay that tracks how we've visualised the brain from times past and includes some of the most stunning images from the last century of neuroscience.

It's been put together by Mo Costandi, the writer you may know from the Neurophilosophy blog, with each image concisely described so you can get an insight into exactly what you're seeing.

Link to 'Time Travel Through the Brain' photo essay.

With uncanny echoes of the modern interest in 'cognitive enhancers', a 1958 edition of Popular Science hails a new drug that "tunes up the brain" allowing us "to perform at peak efficiency all the time".

The drug is iproniazid, marketed then as Marsilid. It was the first ever antidepressant, but the concept of an 'antidepressant' had yet to be created by the pharmaceutical companies and instead it is described as 'psychic energizer'.

It was originally used a treatment for tuberculosis, as it stops the bacterial infection, but it was noticed that patients treated with iproniazid seemed to have a lift in mood at low doses and risked becoming confused and psychotic at higher doses.

At the time, the only widely used psychiatric drugs were tranquilisers, and the idea that a drug might be an 'anti-tranquiliser' was quite puzzling. It was trialled on some patients with diagnoses of mental illness patients and then marketed as a 'psychic energizer'.

According to David Healy's book (p66) on the history of drug treatments for depression, The Antidepressant Era, this label came from the discoverers trying to interpret its effects in Freudian terms - in which 'psychic' is used broadly to mean 'psychological':

Kline and Ostow speculated that as psychic conflicts all involved the binding of psychic energy in various different ways and as a great deal of ego energy went into binding instinctual (or id) energy down to produce a range of inhibited states, it was conceivable that a drug that took energy away from the ego might lead to liberation of instinctual energy - it might be a psychic energizer.

However, the drug was rapidly taken off the market as it was found to damage the liver to the point where a number of patients died of hepatitis.

The Popular Science article is interesting because it is remarkably similar to modern day articles on cognitive enhancers - relating it's effects to improving performance rather than treating an illness and musing over whether healthy people should take drugs to make them 'better than well'.

Therefore, let's imagine that a few years from now there is a psychic energizer known to be completely harmless. And suppose its effect on body chemistry is perfectly normal and natural. In that case, what about the healthy person who just want more vim and vigor to go dancing?

"Well", Dr Kline answers, "why not?" After all, nobody sees anything wrong about a dentist working to give perfect teeth. Why shouldn't a doctor try to give perfect metabolism?

Or perfect tits, as the comparison more commonly goes in the 21st century.

It's an interesting insight into how the drug companies were trying to find a place in the market for their puzzling new compounds in the 1950s and another demonstration of how concerns about 'cognitive enhancers' are as old as drugs themselves.

Link to Popular Science article 'New Drugs to Tune Up Our Brains'.

The 77th edition of the Encephalon psychology and neuroscience writing carnival has just appeared online, this time ably hosted by Sharp Brains.

This edition is rather special as it's a crossing of the streams with the medical carnival Grand Rounds.

A couple of my favourites include Brain Blogger on whether religion can be understood as a natural phenomenon and Advances in the History of Psychology on some of the early experimental work on emotion.

There's many more links to great writing in the blogosphere so do head over and have a look.

Link to Encephalon 77.

A common belief says that eating cheese causes vivid dreams or nightmares. However, I couldn't find any support for the idea in the scientific literature except for one bizarre case study.

Although the case report really tells us nothing about the link between cheese and dreaming, it's lovely to read because it's from a bygone day where doctors could write into medical journals with their strange and idiosyncratic observations.

From a 1964 edition of the British Medical Journal:

I have lately seen a patient with moderate essential hypertension who because of various side-effects with other drugs was changed to pargyline, 25 mg every morning; this gave satisfactory control and within a fortnight the patient volunteered that he felt much less depressed, but was having nightmares.

Inquiry produced the fact that he habitually ate one or two ounces (30-60 g) of Cheddar cheese with his supper every evening. The nightmares were of a horrifying nature, and curiously they were concerned not with his immediate family or friends but with people such as his workmates, with whom he was not in any particular emotional relationship. He dreamt of one, terribly mutilated, hanging from a meat-hook. Another he dreamt of falling into a bottomless abyss. When cheese was withdrawn from his diet the nightmares ceased.

I am, etc. J. CHARLES SHEE, Bulawayo, S. Rhodesia.

The mentioned drug, pargyline, as well as being used for hypertension is in the same class of drugs more commonly used as antidepressants.

These are monoamine oxidase B inhibitors (MAOIs) which prevent the breakdown of the monoamine neurotransmitters serotonin, epinephrine and norepinephrine. However, they also prevent the breakdown of the chemical tyramine which occurs naturally in some foods, such as cheese, some soy bean products, processed meats and some fruit and nuts.

A build up of tyramine can cause an increase in blood pressure which can cause headaches, heart problems and increases the chance of stroke (blood vessel blockage or bleeds in the brain). Hence, people taking MAOI antidepressants have to avoid foods high in tyramine to prevent these potentially lethal side-effects.

Interestingly, the fact that the UK Prime Minister, Gordon Brown, was apparently avoiding similar foods led to internet rumours that he was on these antidepressants, which caused a media flap when the BBC questioned him about his mental health and use of "pills" to "get through".

Link to PubMed entry for case study with full text option.

BBC News has a fascinating short video report of a robotic hand that is connected to the nerve fibres of an amputated arm and which allows the patient to actually feel touches with the robot fingers.

Although it doesn't mention it in the report, the technology is from the SmartHand research group who are attempting to use knowledge about the cognitive neuroscience of action and body sensation to make fully integrated naturally controlled prosthetics.

There's an interesting part of the video where the patient says "When I grab something tightly I can feel it in the finger tips, which is strange because I don't have them anymore".

In other words, despite the fact that the robot hand feeds touch information into the nerve fibres into the arm stump, the patient feels the sensations 'in' the robot fingers.

This is essentially the 'rubber hand illusion' and the same research group demonstrated exactly this in a recent experiment where they induced touch sensations in a robot hand by stroking it and the stump simultaneously.

This is interesting because a recent study found that sensations in people with intact arms only transferred to a realistic looking rubber hand and not a wooden one, whereas this research team uses a obviously false robot limb.

The fact that touches transfer to an obviously false hand for someone with an amputation but not for people with intact limbs is interesting, because it suggests that brain's remaining body-image 'maps' for the amputated hand may be being recruited to enhance the illusion.

Link to BBC News video report "New robotic hand 'can feel'".
Link to SmartHand project.

Sensory deprivation lasting only 15 minutes is enough to trigger hallucinations in healthy members of the public, according to a new study published in the Journal of Nervous and Mental Disease.

The researchers were interested in resurrecting the somewhat uncontrolled research done in the 50s and 60s where participants were dunked into dark, silent, body temperature float tanks where they subsequently reported various unusual perceptions.

In this study the researchers screening a large number of healthy participants using a questionnaire that asks about hallucinatory experiences in everyday life. On the basis of this, they recruited two groups: one of 'high' hallucinators and another of 'low' hallucinators.

They then put the participants, one by one, in a dark anechoic chamber which shields all incoming sounds and deadens any noise made by the participant. The room had a 'panic button' to stop the experiment but apparently no-one needed to use it.

They asked participants to sit in the chamber for 15 minutes and then, immediately after, used a standard assessment to see whether they'd had an unusual experiences.

After a twenty minute break, they were asked again about perceptual distortions to see if there were any difference when normal sensation was restored.

Hallucinations, paranoid thoughts and low mood were reported more often after sensory deprivation for both groups but, interestingly, people already who had a tendency to have hallucinations in everyday life had a much greater level of perceptual distortion after leaving the chamber than the others.

This study complements research published in 2004 that found that visual hallucinations could be induced in healthy participants just by getting them to wear a blindfold for 96 hours.

However, my attention was grabbed by the researchers use of a 'panic button'. The effect of having a panic button in sensory deprivation experiments was specifically studied in 1964 by psychologists Martin Orne and Karl Scheibe. They also asked about hallucinations and compared two groups of people.

One group was met by researchers in white coats, given a medical examination and told to press a 'panic button' if they wanted out. The other was met by researchers in causal clothes, weren't given medical checks, and told to knock on the window if they wanted the experiment to stop.

The actual sensory deprivation part was the same, but the group with the panic button reported many more hallucinations, likely owing to 'demand characteristics', or, in other words, their expectations of what might happen.

We also know that an increase in anxiety also increases the likelihood of hallucinations, and having a 'panic button' during an experiment, I suspect, is likely put most people a little more on edge.

So we can't be sure that the effect was purely due to sensory deprivation, but it does chime with various other studies showing that when we reduce our normal sensations, the brain has a tendency to 'fill in' with hallucinations.

Link to PubMed entry for sensory deprivation study.

With debates still raging over the new version of the psychiatrists' diagnostic manual, the DSM-V, a selection of radical new diagnoses have been submitted which may give the committee pause for thought.

They have been carefully reviewed by Matthew Hutson over at Psychology Today and we include a couple so you can see how this paradigm shift in medical thinking may affect future practice:

Napoleon Complex

Antecedents: Being short, male; having a French accent.

Symptoms: Power-seeking. Attempting to compensate for small stature through aggression, tall hats.

Notes: Despite widespread misconception, Napoleon Bonaparte of France was of average height for his time. He was actually compensating for almost imperceivably asymmetrical nostrils.

Neapolitan Complex (also known as Tripolar Disorder)

Antecedents: Being Italian; nearly drowning in a vat of frozen dairy dessert.

Symptoms: Having a light side, a dark side, and a sickeningly rosy side. Wanting to be everything to everyone. Chronic brain freeze.

There's plenty more in the full piece but on a more serious note, a short article in Psychiatric News reflects on one psychiatrist's attempt to communicate with the DSM-V committee while finding that actually, much of it has already been decided.

Link to humorous diagnostic suggestions at Psychology Today.
Link to Psychiatric Times piece on 'the DSM process'.