March 2010 – Page 2

Dear Lad, there’s no such thing

Spike Milligan was one of the best loved, most influential and least predictable of British comedians, not least because he experienced the highs and lows of manic depression which, on several occasions, led to his hospitalisation.

As a prolific writer Milligan often wrote about mental health and the book, The Essential Spike Milligan, has several of his sketches and poems on the topic.

The book also contains a gem of a letter that Milligan wrote to a student magazine where he expounds upon the difficulty of maintaining one’s mental health in the modern world in his trademark scattershot style.

To the Editor, Rag Mag, Gloucester College of Education, 1968

You say your mag is in aid of mental health! Dear Lad, there’s no such thing, if there was anybody in a position of power with any semblance of mental health do you think the world would be in this bloody mess? Young minds at risk is different. Anyone with a young mind is taking a risk – young means fresh – unsullied, ready to be gobbled up in an adult world bringing the young into the visionless world of adults, like all our leaders. Their world is dead – dead – dead, and my God, that’s why it stinks! They look at youth in horror – and say ‘They are having a revolution’, but what do they want? I say they don’t know what they want, but they know what they don’t want, and that is, the repetition of past mistakes, towards which the adult old order is still heading. War – armistice – building up to pre-war standards – capitalism – labour – crisis – war and so on. I digress.

Mental Health. I have had five nervous breakdowns – and all the medics gave me was medicine – tablets – but no love or any attempt at involvement, in this respect I might well have been a fish in a bowl. The mentally ill need LOVE, UNDERSTANDING – TOLERANCE, as yet unobtainable on the N.H.S. or the private world of psychiatry, but tablets, yes, and a bill for ¬£5 5. 0. a visit – if they know who you are it’s ¬£10 10. 0. – the increased fee has an immediate depressing effect – so you come out worse than you went in.

As yet, I have not been cured, patched up via chemicals, yes. Letter unfinished, but I’ve run out of time – sorry!

Regards,
Spike

Link to details of The Essential Spike Milligan.

An interview on Death and Dying

ABC Radio National’s All in the Mind has an archive interview from 1978 with Swiss psychiatrist Elisabeth K√ºbler-Ross who pioneered the consideration and treatment of the last stages of life as patients were dying of terminal illnesses.

K√ºbler-Ross is best known for her stage model of death and grieving that famously includes denial, anger, bargaining, depression and acceptance. It has been heavily criticised although it’s true to say that many critics miss the fact that K√ºbler-Ross later disavowed that they are sequential psychological reactions and could appear at any time.

Despite this, the model was based on little except personal observation and insight, and seems unable to capture the messiness of genuine grieving. It did, however, act as a lens that concentrated the mind of the medical world on end-of-life care and, in this respect, has been hugely influential.

K√ºbler-Ross became famous after a 1969 article appeared in Life magazine. Entitled ‘A Profound Lesson for the Living’ it finds her discussing death with terminally ill young people, which, at the time, was a difficult and taboo topic.

The All in the Mind interview sees her almost a decade after her work was first widely publicised, and is full of what is now considered to be the received wisdom about dealing with dying patients.

This was exactly the point where K√ºbler-Ross’ star began to fade, however, largely due to her increasing interest in dodgy practices like spirit channelling and association with some guru-like figures of questionable moral standing.

An article from Time magazine in 1979 exposed her increasingly flaky approach to the topic (the last paragraph is high comedy) and was influential in her quiet rejection from the medical mainstream.

The 2002 documentary film Facing Death: Elisabeth Kubler-Ross (a pain to get hold of but available on some torrent servers) captures her when she herself was slowly dying. It looks back on her remarkable and not untroubled life and finds her having difficulty adjusting to her own mortality.

Link to All in the Mind K√ºbler-Ross interview.

2010-03-19 Spike activity

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

New Scientist has an interesting piece on several conditions somewhat clumsily cobbled together as disorders of ‘extreme empathy’ although it’s still a good read.

Ace t-shirt blogger Coty Gonzales turns out the be a cognitive neuroscientist in an interview for Hide Your Arms.

The Guardian have a video interview with evolutionary anthropologist Robin Dunbar on social group size and social networking websites. No word on poking.

The latest research on using fMRI to ‘read’ subjective mental states, this time during memory recall, is expertly covered by Neurophilosophy.

The Economist discusses the latest advances in brain-to-machine connections. Great photo caption.

Food induced seizures. Neuroskeptic covers a case of a woman who had seizures triggered by eating.

Time magazine covers research finding that psychopaths show greater reward system and reward expectation-related dopamine release. This cued lots of vague musing on the personalities of psychopaths in the press.

A Carl Zimmer talk on his excellent book ‘Soul Made Flesh’ on the beginnings of neurology and neuroscience is available on C-SPAN.

Scientific American have released a feature article that isn’t locked behind a paywall. Read the piece on how the brain handles colours and contours before they change their minds.

The UN recently warned of the effects of drug dependence on developing countries and Addiction Inbox covered the debate. Lots of other good posts on AI recently.

BBC Radio 4 had a documentary on the human library, a scheme where instead of borrowing books, you borrow a person to have a conversation with.

Eight studies demonstrating the power of simplicity are covered by the excellent PsyBlog.

Reuters reports that a French reality TV programme recreated the Milgram conformity experiments. Replaces scientist with a Parisian waiter who tuts when the person doesn’t want to continue.

Reminders of disease primes the body and mind to repel other people, according to new research covered by the BPS Research Digest.

Wired Science cover a new neuroimaging study that aims to understand ‘Gulf War Syndrome‘.

Lip reading for the FBI. Sensory Superpowers covers the use of lip reading by the feds and how we all do it to some degree.

New Scientist discusses the use of torture and the future for interrogation.

During recovery, a brain injured man is building an astounding doll universe with himself as a central character, Henry Darger-like in its scope. The blog of the Marwenocol project has lots of detail.

Biologist Lewis Wolpert reviews Greenberg’s ‘Manufacturing Depression’ in The Guardian.

Science News report on a cross-cultural study finding that sharing money on the ‘ultimatum game’ is related to the extent to which the person lived in communities with market economies.

Kids prefer friends whose speech sounds similar to their own, regardless of race, according to research covered by Scientific American Mind.

Psychological Reports has a paper on graffiti addiction!

Some empirical evidence for the ‘extended mind hypothesis’ (we become our tools) is discussed by Wired Science.

The Times reports on the case of a researcher being sued for libel after criticising bogus lie-detector technology. Please sign the petition at LibelReform.org to keep libel law out of scientific arguments.

A bogus TV report of a Russian invasion panics Georgia, according to a report from BBC News.

The Guardian reports on protests in Colombia by people outraged by narco-soaps glamorising cartels.

Thoughts of randomness enhance supernatural beliefs, according to a research covered in a great post from Deric Bownd’s Mind Blog.

Scanning for murder raps

Nature has a freely available feature article that discusses recent debates about how functional brain scans should be used in court cases concerning people charged with murder and classified as psychopaths.

Brain scans that show an estimate of brain activity, such as fMRI, are widely used in forensic and medical research to understand whether offenders and psychopaths differ in how their brain processes information.

These studies usually rely on group differences, showing that, on average, brain activity occurs differently in offenders compared to non-offenders, patients compared to non-patients and so on.

Court cases, of course, attempt to decided whether a single individual is criminally responsible for his or her actions. Inferring individual differences from broad group averages is difficult, some say impossible but despite this, functional neuroimaging is being increasingly used in court.

The Nature article discusses the recent Jeanine Nicarico murder case where Brian Dugan was being charged (and later confessed to) with the young girl’s murder.

Controversially, and for the first time in the US, the court was permitted to see evidence from functional brain scans from neuroscientist Kent Kiehl related to Dugan’s diagnosis of psychopathy.

On 29 October, Kiehl participated in a ‘Frye hearing’ for Dugan’s case. Based on a 1923 ruling, the hearing determines whether scientific evidence is robust enough to be admitted. Joseph Birkett, the lead prosecutor in the Dugan case, argued that allowing the scans ‚Äî the bright colours and statistical parameters of which are chosen by the researchers ‚Äî might bias the jury. Some studies, prosecutors argued, have shown that neuroscientific explanations can be particularly seductive to the layperson.

The judge ultimately “cut the baby in half”, says Birkett. He ruled that the jury would not be allowed to see Dugan’s actual brain scans, but that Kiehl could describe them and how he interpreted them based on his research.

According to the article, the scans had a significant influence on the case and it has raised a heated debated about whether such evidence is possibly interpretable in legal terms.

Neuroscientists are typically harshly critical about lawyers’ enthusiasm for wanting to use less-than-clear cut technologies like ‘brain scan lie detectors’ in court.

However an article recently published in Trends in Cognitive Sciences was very critical of this attitude, noting that the court’s requirements were often different from science’s, and than even suggestive evidence could help fill out the overall picture, and hence it was up to the court to decide whether such evidence should be admissible, not scientists.

Nevertheless, these sorts of arguments raise the hackles of many researchers and neuroscientist Helen Mayberg is quoted in the Nature piece as saying “It is a dangerous distortion of science that sets dangerous precedents for the field”.

The article is great coverage of the particular case and an interesting look into how neuroscience research is being uncomfortably integrated into the legal system.

Link Nature article ‘Science in court: Head case’ (via @mocost).

Lords, ladies and video games

I attended the All-Party Parliamentary Group on Scientific Research in Learning and Education yesterday to discuss “What is the potential impact of technology, such as computer gaming, on the brain?” alongside Baronness Susan Greenfield and we were pleased to be able to present to a packed committee room.

I’ve never met Greenfield before, who was a big influence on me when I decided to become a neuropsychologist, and it was a genuine pleasure to meet her in person.

We started off the talks and it turns out we agree on quite a lot. Greenfield doesn’t want to ban computer games or internet applications but feels parents should be more involved in their kids’ media use to guide them to use it safely and sensibly. She also feels that most kids use technology well and get benefits from it but is concerned about the few that might “fall through the cracks”, or as I would describe them, the few who are a high risk group for unhealthy use.

It seems we agree on the implications, and it was clear the Greenfield is motivated by a genuine concern for young people.

Her talk was sincere, very well delivered but unfortunately her argument was poorly lacking in terms of its scientific content, and I’m afraid to say, wouldn’t pass muster as an undergraduate thesis. This was not least because she discussed not a single study on the effect of games or the internet.

I started my talk by searching PubMed, the database of medical research, to show that there are more than 1,500 published articles in the medical literature that directly discuss computer games.

Many of these studies investigate the concerns she has about whether games might be affecting attention spans or whether online communication could be harming the social life of young people, but she seems unwilling to consider any of them. For someone who is leading the public debate on this issue I find this, at best, baffling.

Greenfield’s justification is entirely based on the idea that young brains are sensitive to their environment, which shapes their development, and so any risks from screen technology might cause significant and unwanted neurological changes. This is, of course, plausible but cannot be evaluated in isolation from the studies that have directly tested the idea.

While I agree with the justification, I’m afraid I found her model of how this might occur also lacking. Not least as it had unspecified and too-broad-to-be-plausible aspects such as dopamine release, caused by gaming, leading to a reduction in frontal lobe activity.

If you want to see my talk, I’ve put the slides from my talk online as a PowerPoint file and apparently, both sets of slides will appear on the website of the Institute for the Future of the Mind shortly, possibly with video as the talks were filmed.

During the talk I made it clear that ignoring the evidence on this issue does a disservice to young people and discussed some of the key findings from the last few decades of research in this area – not least that action video games have been shown to improve cognitive function but that we should be concerned about content and age appropriateness (e.g. violence) and displacement of other activities (such as education, exercise and so on). I also discussed evidence showing that the internet seems to be benign or beneficial for the social lives of the majority of young people who use it.

Greenfield noted, however, that not all of her concerns are addressed by the studies I mentioned (for example, that computer games might affect the ability to use metaphor and understand abstract concepts) and that some, possibly unwanted, outcomes will just not be measurable. Even though I find some of her concerns a little far-fetched, she has a valid point on how we should be aware of the limits of what empirical research can deliver for complex social issues.

The discussion afterwards was lively and constructive. We had input from someone working on the Digital Economy Bill, a head teacher, a paediatrician, educationalists, a Lord who – against all my prejudices – clearly knew shit loads about computers and several people who just spoke from their experience as parents.

Afterwards, Greenfield invited everyone for a drink and was a funny and engaging host and I got the chance to thank her for inspiring me when I was starting out.

I have a different opinion of Greenfield after the debate, as I previously suspected she had been struck by reactionary technofear but was mistaken, as she does want children to benefit from technology. She obviously thinks a lot of internet culture is trash, but when you look at the constant stream of seemingly irrelevant in-jokes and funny cat videos, I can hardly blame her for this.

Nevertheless, I think her passion for helping young people has overtaken her obvious good sense as a scientist and a scholar on this issue, and I would join the call for her to write her ideas up for publication in a scientific journal both to clarify her position and to stimulate engagement with the large evidence base that she is currently unfamiliar with.

I have criticised Greenfield’s more alarmist public statements in the past, but with her passion and experience as a neuroscientist, a well-informed Baroness Greenfield would be a massive advantage to the debate on how we ensure children learn to manage technology to their best advantage.

ppt of slides from my talk.
Link to All Party Parliamentary Group description.

Full disclosure: The Institute of Psychiatry kindly helped fund my airfare and I wouldn’t have been able to attend without them, so many thanks for their support and belief in public and policy engagement.

Is this the boss level?

I’m just about to go to the All-Party Parliamentary Group on Scientific Research in Learning and Education to discuss “What is the potential impact of technology, such as computer gaming, on the brain?”.

It turns out Baroness Susan Greenfield will be talking first, followed by me, followed by a discussion with all in attendance.

After forgetting my tie and having to buy one from Tie Rack in Waterloo station, I am all ready to go. I’ll upload my slides afterwards and will report how it went.

A very historical madness

H-Madness is a fantastic new blog on the history of madness written by professional historians with a clear passion for their work.

Although aimed at “university and college faculty, students, and independent researchers” it is written in a striaghtforward style and includes original articles, book and film reviews, as well as news about academic publications, events and talks.

There are occasionally posts in French or German, which, to be honest, I find a bit annoying as I can’t read them and they often look very interesting, although you’ll often find an English translation just below.

It’s a great read and makes a fine compliment to existing high quality history sites like the Advances in the History of Psychology blog and The Neuro Times.

Link to H-Madness (via Somatosphere).

Roald Dahl’s Marvelous Medicine

Author Roald Dahl was particularly well known for darkly humorous children’s books that form a riotous part of almost every childhood in Britain. Less well known is that he also made some significant contributions to neurology, as detailed in a brief article for Advances in Clinical Neuroscience and Rehabilitation.

The article is available online as a pdf and starts by noting that several of his books contain possible nods to neurological syndromes or fantastical fictional experiments.

These descriptions may hardly be termed “contributions” but two personal tragedies certainly did lead to developments of clinical import. Whilst living in New York in 1960, Dahl’s son Theo, aged 3-4 months, was involved in a road traffic accident which caused some brain damage and secondary hydrocephalus [a dangerous problem preventing cerebrospinal fluid drainage in the brain], the latter requiring shunting. Problems with blocked shunts occurred. The family returned to England and Theo came under the care of Kenneth Till, a neurosurgeon at Great Ormond Street Hospital (1956-80). Prompted by Dahl, and in collaboration with Stanley Wade, an hydraulic engineer, a new type of shunt valve was designed. Reported in the Lancet by Kenneth Till, under the rubric of “New Inventions”, the special characteristics were reported to be “low resistance, ease of sterilisation, no reflux, robust construction, and negligible risk of blockage”. The author acknowledged that the valve was “designed by Mr Stanley C.Wade… with the assistance of Mr Roald Dahl and myself”. The Wade-Dahl-Till (or WDT) valve became widely used.

Kenneth Till subsequently wrote a preface for a new edition of Valerie Eaton Griffith’s book entitled A stroke in the family, a manual of home therapy, wherein lies another Dahl connection. In 1965, Dahl’s first wife, the American actress Patricia Neal, suffered a stroke due to a ruptured intracranial aneurysm, one of the consequences of which was marked aphasia, a potential career-ending misfortune for an actress (her illness and recovery are recorded in a book by Barry Farrell). Dahl appealed to Valerie Eaton Griffith, who lived in the same village, for help. With Dahl, she devised a rota of volunteer carers to engage the patient in conversation and hence to stimulate language recovery. This approach, different from formal speech therapy, was documented in Griffith‚Äôs book (initially published in 1970, with an introduction by Roald Dahl). It earned the approbation, as “treatment of a surreptitious character” of no less a neurological figure than Macdonald Critchley, and still has advocates today. It has been suggested that Patricia Neal’s aphasia may have influenced Dahl’s creative processes, for example in the neologisms of The BFG (1982).

The EEG unit at Liverpool’s Alder Hey Children’s Hospital is called the Roald Dahl EEG Unit but I’d never made the connection before.

Dahl was not the first father to be motivated to create a shunt to treat his child. As we discussed previously, engineer John Holter found himself in a very similar position and invented the Holter shunt to treat hydrocephalus in his daughter.

pdf of article on Roald Dahl’s neurological contributions.

Falling in love with epilepsy and St Valentine

I was surprised to find out that as well as being the patron saint of love, St Valentine is also the patron saint of epilepsy. I’ve just found a study that analysed six centuries of artistic depictions of the holy figure where he is often accompanied by people having seizures.

The paper has a good description of St Valentine’s historical association with what was known as the “falling sickness” or “the sacred disease”. This link to the condition may be based on little more than the fact that his name sounds like the old German word for fall.

In Christianity, saints were of great significance in the treatment of severe and chronic illnesses, as their intercession with God was considered to have a great therapeutic effect on human ailments. In some illustrations of SV [Saint Valentine], the aspect of exorcising demons in connection with epilepsy is depicted as a demon flying out of the mouth of a sick person [see image on left].

Of the more than 40 named “epilepsy saints” (among others, Aegidius, Anastasia, Antonius, Cosmas, Cyriacus, Damian, John the Baptist, Ladislas of Hungary, Veit, Zeno), SV was the most well known and he was the saint who was invoked most often. Today, we can no longer verify whether his patronage was based on the phonetic use of his name with the word fall, as Luther had suspected, or on an incident in his legend (SV is said to have healed a person with epilepsy).

Two saints with the name Valentine were and are worshipped in the Roman Catholic Church: Valentine of Terni, patron saint day February 14, and Valentine of Rhaetia, patron saint day January 7. Valentine of Rhaetia is one of the patron saints of the Passau/Bavaria and Chur/Switzerland dioceses. People with epilepsy are portrayed in illustrations of both Valentine of Terni and Valentine of Rhaetia.

It is likely that two saints with the name Valentine had their patron saint day on February 14. Although the two SVs are sometimes entered separately in martyrologies and biographies, most scholars believe they are the same person. The patronage is complex, as SV’s help is invoked not only against diseases of cattle and pigs, but also against a host of human ailments, such as diseases of the uterus, gout, and, most notably, fainting, madness, and epilepsy. The use of pigs as attributes in illustrations of SV leads us to assume that there is also a reference to the description of the “healing of the demoniac of Gadara” (Mark 5:1–19; Lucas 8:26–40; Matthew 8:28–34). This passage in the Bible is interpreted as the curing of a person who possibly had epilepsy…

In medieval German language, the “falling sickness” was sometimes referred to as “St. Valentine’s illness, St. Veltin’s infirmity”.

The article is full of wonderful historical illustrations of St Valentine surrounded by or curing people with epilepsy, but sadly the article is locked behind a pay wall.

Link to PubMed entry for St Valentine art and epilepsy study.

An introduction to cognition and culture

The Culture and Cognition blog covers the territory where culture and psychology meet, and they’ve just released their ‘reader‘ which has a list of essential books and papers to cover the interface between anthropology and the cognitive sciences.

Many of the articles are available in full online and the list is a fantastic guide to the area.

It includes both popular and academic texts but the list works best as a reference, so bookmark it as I’m sure you’ll be returning to it time and again if you’re like me and interested in the cross over between culture and psychology.

Link to Cognition and Culture Reader.

2010-03-12 Spike activity

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

The University of California has an interview with space psychiatrist Nick Kanas

There’s a thoughtful consideration of the recent New York Times article on whether depression has evolutionary benefits over at Neuron Culture.

Time magazine discusses research finding that deaths from cocaine overdoses rise even when the weather warms up only slightly.

We’re slower at processing touch-related words than words related to the other senses, according to new research covered by the BPS Research Digest.

Wired UK discusses a new study on how electrical brain activity recorded from the scalp’s surface is enough to support the (rough) reconstruction of 3D hand movements on a computer.

The bizarre double life of Dr. William Stewart Halsted is discussed in a book review over at The Neuro Times.

The Neurocritic welcomes yet another attempt to resurrect Freudian ideas about the brain with a new paper taking the ‘but looks at the similarities!’ approach.

Male batterers consistently overestimate rates of domestic violence, according to a study covered in e! Science News

Not Exactly Rocket Science on how cooperative behaviour spreads through social networks, but so does cheating.

Asking an experienced stranger predicts our future happiness better than we can ourselves. A nugget from a piece on the work of Daniel Gilbert over at Harvard Magazine.

Neurophilosophy discusses some new lab research suggesting that the immune system response to brain infection may trigger Alzheimer’s disease.

The somewhat chilling piece on the rise of ‘human flesh search engines’ in China is discussed by The New York Times.

Deric Bownd’s Mind Blog covers a fascinating study that found thinking about randomness enhanced belief in the supernatural.

The UK’s programme to detain and treat people with ‘Dangerous and Severe Personality Disorder’ is heavily criticised in a government report. New Scientist covers the story.

Seed Magazine asks ‘is there an evolutionary basis for our religious beliefs?’ I for one know that my belief in Thor makes me more attractive to the ladies.

Bigger men are more aggressive when drunk, according to research covered by Science News.

Neuroanthropology discusses why students drink before even leaving the door to party, a practice known as ‘pre-gaming‘. The site also has an excellent essay on how obesity is discussed as a medical problem.

A variant of gene SCN9A has been linked to pain perception, according to a new study covered by Science News.

The Loom discusses how bacteria could change our behaviour. I expect to see ‘the bacteria made me do it’ defence in court cases some time soon.

Fat may be detectable as a ‘sixth taste‘ suggest a new study covered by Wired UK.

Newsweek thinks fMRI “proves” addiction is a brain disease (hello neuroessentialism fallacy!) while making an otherwise important point on the need for psychological treatment for addiction.

A long but interesting piece on how to train teachers with simple effective classroom techniques appeared in The New York Times.

RadioLab discusses “a rare but disturbing delusional disorder called Capgras” in one of its excellent short broadcasts. Although it’s not actually that rare in people with psychosis and dementia.

Back to blightly

Apologies if updates are a little irregular, as I’m currently on my way back to the UK for a three week visit. This is largely because I’ve been asked to speak to the ‘All-Party Parliamentary Group on Scientific Research in Learning and Education’ about the evidence for whether computer games are damaging kids’ brains. I kid you not.

I shall also use the opportunity to catch up with the fantastic research group I’m associated with at the Institute of Psychiatry, but I’ll largely be sleeping on sofas, floors, buses, park benches and the like, so do forgive any irregularity or incoherence (although regular Mind Hacks readers seem quite well accustomed to both by now, and for some of you, I suspect it’s part of the attraction).

In the Exploratorium’s distorted room

The San Francisco Exploratorium is the Mind Hacks of science museums – every exhibit is hands on, giving you the chance to experiment with and experience for yourself scientific principles.

Obviously, one of my favourite exhibits was a psychology demonstration, one based on a classic visual illusion known as the “Ames’ Room”. We’ve a small model of this in Sheffield, which I use when teaching PSY101, but the Exploratorium’s “distorted room” is full size demonstration of the effect. Here’s me and a friend in the room:

Notice anything odd? We’re the same size in reality, but I (on the right) look significantly larger.

The illusion takes advantage of the unavoidable principle that size and distance are confounded – known as “Emmert’s Law“. It is Emmert’s Law that means that big things far away can look the same size as small things near by. Our brain makes assumptions about how far away things are and uses these to inform our impression of size. The distorted room is built so that, from one perspective only, the two sides of the room look an equal distance away. In fact, the corner on the right is far closer to the viewer (the camera in this case) than the corner on the left. Because I really am nearer the camera I make a larger image on the retina (take up more pixels on the camera), but because the brain assumes that I am the same distance away as my friend on the left the only conclusion that my visual system can draw is that I must be much larger than him.

Normally your visual system isn’t fooled about depth – clues in the scene, the difference between the image on your two eyes and movements of your head can all help reveal how far away different parts of the scene are. The distorted room removes some of these clues by forcing you took look at the room with one eye from a fixed point, and other clues it deliberately tricks (like the shape of tiles on the floor, which look the same from left to right, but actually get smaller, because the tiles on the right are closer).

The confounding of size and distance is the same principle behind illusions like this:

The effect only works because it is in a photograph (so from one perspective) and because the relatively featureless desert removes other clues to the depth of objects.

So the next time you close one eye and line up someone in the distance between your thumb and forefinger while muttering “I’m crushing your head!“, think of Emmert’s Law. And if you are in San Francisco, visit the Exploratorium!

How cannabis makes thoughts tumble

Cannabis smokers often report that when stoned, their thoughts have a free-wheeling quality and concepts seem connected in unusual and playful ways. A study just published online in Psychiatry Research suggests that this effect may be due to the drug causing ‘fast and loose’ patterns of spreading activity in memory, something known as ‘hyper-priming’.

Priming is a well studied effect in psychology where encountering one concept makes related concepts more easily accessible. For example, classic experiments show that if you see the word ‘bird’ you will react more quickly to words like ‘wing’ and ‘fly’ than words like ‘apple’ and ‘can’ because the former words are more closely related in meaning than the latter.

In fact, it has been shown that the more closely related the word, the quicker we react to it, demonstrating a kind of ‘mental distance’ between concepts. Think of it like dropping a stone into a pool of mental concepts. The ripples cause activity that reduces in strength as it moves away from the central idea.

‘Hyper-priming’ is an effect where priming happens for concepts at a much greater distance than normal. For example, the word ‘bird’ might speed up reaction times to the the word ‘aeroplane’. To return to our analogy, the ripples are much stronger and spread further than normal.

The effect has been reported, albeit inconsistently, in people with schizophrenia and some have suggested it might explain why affected people can sometimes make false or unlikely connections or have disjointed thoughts.

As cannabis has been linked to a slight increased risk for psychosis, and certainly causes smokers to have freewheeling thoughts, the researchers decided to test whether stoned participants would show the ‘hyper-priming’ effect.

The experiment used a classic ‘lexical decision task‘ where the volunteers are shown an initial word (‘time’) and then after a short gap are shown a nonsense word (‘yipt’) and a true word (‘date’) at the same time and have to indicate as quickly as possible which is the real world.

The experimenters altered how related the initial word and true word were to test for the semantic distance effect, and also varied the gap between the initial word and the test to see how long the priming effect might last.

Volunteers who were under the influence of cannabis showed a definite ‘hyper-priming’ tendency where distant concepts were reacted to more quickly. Interestingly, they also showed some of this tendency when straight and sober .

Cannabis also had the effect of causing temporary psychosis-like distortions as would be expected from a psychedelic drug, but the smokers did not make more errors and were not more likely to report psychosis-like symptoms when sober, suggesting the effect was not due to general mental impairment and couldn’t be explained by underlying tendency to mental distortion.

Although the debate is not completely settled, there is now good evidence that cannabis causes a small increased risk for developing schizophrenia particularly when smokers start young. In fact, additional evidence on this front was published only this week.

The researchers discuss the possibility that long-term smokers who spend a lot of time in a chronic ‘hyper-primed’ state might make psychosis more likely by loosening the boundaries of well-grounded thought, although exactly how cannabis raises the risk of psychosis, and indeed, how exactly it affects the brain, is still not understood well-enough to make a firm judgement.

Link to PubMed entry for cannabis ‘hyper-priming’ study.

Tracking the unborn brain into childhood

A brain scanning technology called MEG is being used to track the function of unborn babies’ brains as they grow inside the womb until after they’ve been born.

The full name for MEG is magnetoencephalography and it works by reading the magnetic fields created by the electrical signalling in the brain.

One of the advantages is that it can be used at various angles, doesn’t require the person to be in a cramped space, and is less sensitive to movement, so is ideally suited to scanning babies.

This includes unborn babies and with a bit of modification, as illustrated in the picture, researchers can pick up signals from the fetal brain in response to flashes or light or sounds.

We discussed the use of fMRI to scan the fetal brain previously, but this is a remarkable study that scanned the brains of babies inside the womb, every two weeks from week 27 until delivery, and then once after they were born.

Clearly, unborn babies are not the best at doing tasks set by experimenters, but there are various tests that just require the individual to experience changes in what’s presented to them.

One is called the auditory oddball task, where a series of tones are played that can either be similar (‘beep beep beep’) or can have include an ‘oddball’ (‘beep beep boop’). The brain is very good at picking out differences and the oddball is known to reliably trigger brain signals related to detecting changes.

This was the exact task used with the babies and the researchers looked to see if they could pick out a brain reaction to the ‘oddball’.

They found that they could detect this response 83% of the time in unborn babies, and that the reaction to the ‘oddball’ increased in speed throughout pregnancy. The newly born babies showed the response every time without fail.

This is an impressive finding as it shows how the brain development of the unborn child can be tracked over time with a brain scanner.

In a recent review article that discusses the development of this technology, the same group of researchers suggest that these and similar techniques could help track how different conditions in the mother affect the developing brain and even how the brain begins to develop its understanding of speech sounds before birth.

Link to PubMed entry for MEG study of developing fetus.
Link to PubMed entry for review article on fetal MEG.

A man with virtually no serotonin or dopamine

Neuroskeptic covers a fascinating case of a man born with a genetic mutation meaning he had a severe lifelong deficiency of both serotonin and dopamine.

The case report concerns a gentleman with sepiapterin reductase deficiency, a genetic condition which prevents the production of the enzyme sepiapterin reductase which is essential in the synthesis of both dopamine and serotonin.

The most widely recognised symptoms of the condition, linked to the deficiency in dopamine which has an important role in controlling movement, are problems coordinating both conscious movements and the unconscious control of muscles that allows simple actions. Unconscious control requires that the brain signals one muscle to contract while releasing the complementary muscle, and problems with this process cause spasticity.

The effects the condition on serotonin, often stereotyped as the ‘happy chemical’, are less well known, but in this case it was clear that the patient wasn’t depressed but did some other difficulties:

These included increased appetite – he ate constantly, and was moderately obese – mild cognitive impairment, and disrupted sleep:

“The patient reported sleep problems since childhood. He would sleep 1 or 2 times every day since childhood and was awake during more than 2 hours most nights since adolescence. At the time of the first interview, the night sleep was irregular with a sleep onset at 22:00 and offset between 02:00 and 03:00. He often needed 1 or 2 spontaneous, long (2- to 5-h) naps during the daytime.”

After doctors did a genetic test and diagnosed SRD, they treated him with 5HTP, a precursor to serotonin. The patient’s sleep cycle immediately normalized, his appetite was reduced and his concentration and cognitive function improved (although that may have been because he was less tired)…

Overall, though, the biggest finding here was a non-finding: this patient wasn’t depressed, despite having much reduced serotonin levels. This is further evidence that serotonin isn’t the “happy chemical” in any simple sense.

This is another piece of evidence against the common myth that depression is “caused by low serotonin” although Neuroskeptic speculates whether the link between disrupted sleep and depression may indicate an effect of serotonin dysfnction.

Link to Neuroskeptic on ‘Life Without Serotonin’.
Link to summary of scientific paper.