Month: May 2007

The strength of weak touches

The BPS Research Digest covers a simple yet fascinating study on the power on lightly touching someone’s arm when trying to persuade them.

In this case, the psychology study involved a man asking women to dance or for their phone numbers.

A good-looking man approached 120 women in a night club over a period of three weeks, and asked them to dance. It was in the name of science – the man was an assistant to the psychologist Nicolas Guegen. Remarkably, of the 60 women who he touched lightly on the arm, 65 per cent agreed to a dance, compared with just 43 per cent of the 60 women who he asked without making any physical contact.

A second study involved three male research assistants approaching 240 women in the street and asking them for their phone numbers. Among those 120 women who the researchers touched lightly on the arm, 19 per cent agreed to share their number, compared with 10 per cent of the women with whom no physical contact was made.

Christian has a fantastic talent for finding really intriguing studies and this is a particularly good example.

Have a look at his article for more on why this effect might occur.

Link to BPSRD on ‘The power of a light touch on the arm’.

Selling disgust

An article in Time magazine discusses how an understanding of the psychology of disgust is being applied to selling products and the arrangement of items in supermarkets.

One key finding has been that disgust is heavily linked to ideas of contamination and this holds even when there’s no risk – just the idea is enough.

For example, people are less likely to want to put a plastic spoon in their mouth that has touched fake plastic vomit, despite the fact that it is no more risky than putting a spoon in your mouth that has touched other plastic spoons in the packet.

Psychologists Andrea Morales and Gavan Fitzsimons has discovered that this principle applies to consumer products that are linked to things that can trigger disgust – rubbish bags, nappies, toilet paper and so on.

Crucially, the contamination principal works here, so people view things less favourably that have been near these products.

Strong preferences were just what the subjects exhibited. Any food that touched something perceived to be disgusting became immediately less desirable itself, though all of the products were in their original wrapping. The appeal of the food fell even if the two products were merely close together; an inch seemed to be the critical distance. “It makes no sense if you think about it,” says Fitzsimons. More irrationally still, the subjects were less comfortable with a transparent package than an opaque one, as if it somehow had greater power to leak contamination. Whatever the severity of the taint, the result was predictable…

“More and more stores organize products by category,” says Morales, “so you have a baby aisle, for example, with diapers and wipes and baby food all together.” Supermarkets might want to rethink that arrangement.

Link to Time article ‘The Science of Disgust’.

Dispelling ghostly images with electromagnets

In a study investigating how the brain generates paranormal experiences and psychotic states, researchers used strong electromagnets to alter brain function and found they could reduce the number of times healthy volunteers saw spontaneously experienced false perceptions.

The researchers altered the function of the temporal lobes with a method called transcranial magnetic stimulation or TMS while participants were asked to detect supposedly ‘hidden’ images in what were actually completely random dot patterns.

When compared to a control area at the top of the head, reducing left temporal lobe function significantly reduced the number of false perceptions.

During the procedure, participants were asked to look at a series of quickly presented dot patterns and told to indicate which had images ‘hidden’ within them.

Crucially, they were told not to guess and only to press a button when they genuinely detected a ‘hidden’ image. In actual fact, all the dot patterns were completely random and none contained ‘hidden’ images, so every ‘detect’ response was a false perception of meaningful information.

Just before each dot pattern was presented, the brain was stimulated with a pulse of TMS, either to the left or right temporal lobe, or a control spot at the top of the head known as the vertex.

TMS uses magnetic pulses to safely ‘switch off’ a small area of brain for a several hundred milliseconds.

When compared to the control area, temporarily ‘switching off’ an area on the left temporal lobe significantly reduced the number of false perceptions, suggesting that this brain area is likely to be involved in making meaningful connections, even when there’s no meaning to be found.

Seeing meaningful information in random data is known as ‘apophenia’ and statistically is known as a false positive or a Type I error.

Previous research has shown that this tendency is known to be enhanced in people who report high levels of paranormal experience, and to a greater extent, in people who experience psychosis – the mental state involving delusions and / or hallucinations that is most commonly linked to schizophrenia.

Other evidence suggests that differences in temporal lobe function are common in people diagnosed with schizophrenia.

The paper is published in the May edition of Cortex, but a pre-print is available at the link below if you don’t have access to the journal.

pdf of full-text paper.

Disclaimer: This study is from my own research group

Wiring the brain for synaesthesia

Neurophilosopher has a great article on a brain scanning study showing that people with synaesthesia have different patterns of brain connections compared to non-synaesthetes.

You read a lot of articles on the brain that use phrases like “wired differently”, suggesting that the connections in the brain are altered.

As the connections in our brain are changing all the time at the dendrite level, often this is just a meaningless way of saying “there’s a difference”.

Perhaps these sort of phrases are best applied to white matter which is the nearest you’ll find to genuine wires in the brain.

White matter fibres run in bundles, they carry electrical signals, and they are insulated by a fatty covering called myelin.

The connections of white matter have been quite hard to study in living people until the development of diffusion tensor imaging (DTI), a brain scanning technology that can specifically pick out the white matter fibres and create maps like the one in the picture.

Rarely when articles talk about “different brain wiring” do they actually mean detectable differences in white matter though.

In the DTI study covered by Neurophilosopher this is exactly what was studied, and it does indeed seem to be different in people who experience synaesthesia, a condition where some of the senses are crossed so, for example, numbers might be also experienced as colours.

DTI is a type of magnetic resonance imaging (fMRI) that measures the diffusion of water molecules. In the brain, water diffuses randomly, but tends to diffuse easier along the axons that are wrapped in myelin, the fatty protein that insulates nerve fibres. Diffusion tensor imaging can therefore be used to infer the size and direction of the bundles (or “fascicles”) of white matter tracts that connect different regions of the brain (above).

The Dutch researchers show that synaesthetes have more connections between the two adjacent areas in the fusiform gyrus than non-synaesthetes. They report their findings in the June issue of Nature Neuroscience.

As well as showing these differences between synaesthetes and non-synaesthetes, the authors also show that there are also differences in connectivity between synaesthetes who differ in the intensity of their sense-mixing experiences.

In other words, the researchers found people with synaesthesia had white matter ‘wiring’ between sensory areas that others don’t have, and that this wiring differed depending on how much synaesthesia the participants experience.

Just from the fantastically straight-forward explanation of DTI imaging given above, you can see that it’s a wonderfully written article.

Have a look at the full piece for more on this fascinating study.

Link to Neurophilospher on ‘Imaging of connectivity in the synaesthetic brain’.
Link to abstract of scientific study.

Neuroplastic fantastic

The New York Times has a review of a new book on how people have overcome brain damage through neuroplasticity – the brain’s ability to re-organise itself.

While this is nothing new, the brain has always had this ability, the discovery is relatively recent and rehabilitation is increasingly designed to take advantage of this process.

The book is called The Brain That Changes Itself and is apparently a series of case studies of how people’s lives have been improved by technology, psychotherapy or behavioural changes.

I suspect much of the excitement about neuroplasticity has been generated by the popularity of ‘cognitive fitness’ games, books and video games, all of which are based on the idea that you can ‘train your brain’ like a muscle.

While there is some truth in this, the effects are much less than many people might expect and certainly, most people don’t completely recover from brain injury.

I wonder if this book, like Peter Kramer’s 1994 book Listening to Prozac (ISBN 0140266712), will showcase the success stories, while most people’s experience will be much more modest.

There’s certainly nothing wrong with presenting the highlights of new and exciting therapies, but I wonder whether it raises some people’s expectations unrealistically.

Anyway, I’ve not read the book yet so I will have to see how it is tackled when I get a copy, and we’re certainly crying out for an accessible treatment of the subject.

Brain Damage, Brain Repair (ISBN 0198523378) is a great academic text, but it’s hardly something you’d take to the beach with you.

Link to NYT review.
Link The Brain That Changes Itself book / author’s website.

Memory exploratorium

San Francisco’s interactive science museum Exploratorium has a fantastic online memory exhibit, that includes articles, games, demonstrations and lectures from leading memory researchers.

The exhibit looks at the science of memory, as well as how it is used in art.

There’s a great article that explains memory distortions via Philip K. Dick and a try-it-yourself demonstration.

And for some unknown reason there’s a slideshow of a sheep brain dissection, when what would be genuinely informative would be to see the memory structures in the human brain.

It’s like going to an air show and watching someone take a bicycle apart.

Apart from that, the site’s fantastic. The lectures are particularly good. Most cover the science of memory, but one is on ideas of forgetting in myth and story.

Link to Exploratorium memory exhibit.

Finding the wily thief

A study that followed the lives of young males for 20 years has found that cognitive ability predicted whether the person was likely to engage in violence or theft if they had a tendency for antisocial behaviour.

Way back in ’79, the researchers recruited 698 males from 12 to 18 years of age from a random telephone survey in New Jersey. They kept in contact with them until the year 2000.

The researchers interviewed the participants and asked about any antisocial behaviour or offences.

They also tested the participants using neuropsychological tests of verbal IQ and executive function – the ability to co-ordinate mental resources that is closely linked to the frontal lobes.

In the males who did end up engaging in antisocial behaviour, the ones with cognitive difficulties tended to be violent, while the ones who were cognitively more able tended to steal.

In other words, low mental ability was associated with violence while the brighter individuals tended to engage in theft.

This could be because successful theft could require more thought, from planning a robbery to tricking another individual, whereas successful violence just requires a target.

One of the difficulties in interpreting these sorts of studies, is that they rely on participants admitting their own offences, so maybe more intelligent people are likely to describe their crimes differently.

However, it certainly wasn’t the case that more able people simply kept quiet about antisocial behaviour, as both reported wrongdoings, but of a different type.

UPDATE: Romeo Vitelli makes an interesting point in the comments:

All things being equal, theft is regarded as being less serious than violence is. Given that this study depends on self-report, are the ones who commit violence less likely to admit to committing violent crimes than the ones who commit theft?

Link to abstract of scientific paper.
Link to brief jargon-free summary.

The paradoxes of mental accounting

The Washington Post has a fascinating article on the psychology of mental accounting – a seemingly simple process but one which seems to have curious effects on how we decide to spend our money.

The article suggests we mentally divide our money for different purposes, and tend to be reluctant to change our thinking, even when it is against our interests.

There’s a nice example of turning up to the cinema and discovering you’ve lost your $20 ticket. How would you feel about shelling out for another one?

Compare this situation to one in which you turn up to the cinema to buy a ticket, but find you’ve lost a $20 bill. How would you feel about buying a cinema ticket in this situation?

Intuitively, it seems as if the first situation is worse, because you’re buying another ticket, when, in fact, the loss is exactly the same in both situations.

It also seems that we assign different sources of money to different purposes, despite the fact that money is completely interchangeable:

Arkes and his colleagues once cited an anecdote in a study: Employees of a publishing firm who were in the Bahamas for an annual meeting were each given a cash bonus for getting a big contract. Almost to a person, the bonus recipients took the money to a local casino and blew it. What is interesting is that most of these people did not lose more than the $50 — they slowed down or stopped when they felt they were playing with their “own” money rather than with the $50 of “free” money. The irony, of course, is that the $50 these people lost was their own money, too.

The article has got some more great examples of how we make spending decisions based on our own idosyncratic internal accounting schemes.

UPDATE: An interesting note from jswolf19, grabbed from the comments:

In my mind, the loss of the ticket and the loss of $20 are not the same. It’s possible that I might find either the ticket or the $20 later (that it’s misplaced instead of lost). However, the ticket will have become useless to me whereas the $20 will not have.

Link to Washington Post article ‘mental accounting’ (thanks Enchilada!)

Virtual insanity

Wired and The New York Times have just each published an article about the use of virtual reality to simulate the experiences of schizophrenic psychosis. This is a PR success for its creator, Janssen-Cilag Pharmaceuticals, but its hardly news, as they’ve been showing the system since 2000.

The system originally had the appalling name ‘Paved With Fear’ and was unveiled in September 2000.

The company, who manufacture the antipsychotic drug risperidone (aka Risperdal), toured the world with the ‘Paved with Fear’ truck.

The rig allows users to put on the VR goggles and explore a virtual world, while the software is programmed to simulate hallucination-like experiences – abusive voices, visual scenes transforming into sinister images and so on.

It was covered in 2002 by an NPR radio show that has some audio and images from the simulation.

In one simulation, a schizophrenic has auditory and visual hallucinations while trying to refill a prescription, and sees the word “poison” on a bottle of pills.

Its not often you meet psychotic patients who hallucinate drug company PR, but Janssen seem to think that refusing their product is a sign of madness.

The system has been taken around the world and show to police, psychiatrists and families of people with mental illness.

The system has since been re-branded with the less stigmatising name ‘Virtual Hallucinations’ and continues to make the headlines, despite the fact that many other people have used VR to simulate psychosis.

I wrote an article in 2004 about some of the systems and talked to their creators, and got some feedback from a programmer and a psychologist who have experienced psychosis themselves.

They concluded that while VR simulations might be a useful simulation of the perceptual disturbance in psychosis, it also involves distortions of meaning and thinking that can’t be captured.

The systems covered in the article were based on experiences taken from patient interviews and were made independently.

Psychiatrist Dr Peter Yellowless recently published a paper on the system he developed, and one system has been built in online virtual word Second Life. There are instructions online so you can try it yourself.

Link to NYT article ‘A Virtual Reality That’s Best Escaped’.
Link to 2004 article on using VR for psychosis simulation and research.
Link to summary of Yellowlees’ paper on psychosis simulation.
Link to instructions for Second Life simulation.

Polish psychologists ordered to assess Tinky Winky

A Polish government minister has ordered psychologists to investigate whether BBC TV show Teletubbies promotes homosexuality in children.

Yes, you read that right the first time.

Here’s some of the story from BBC News:

The spokesperson for children’s rights in Poland, Ewa Sowinska, singled out Tinky Winky, the purple character with a triangular aerial on his head.

“I noticed he was carrying a woman’s handbag,” she told a magazine. “At first, I didn’t realise he was a boy.”

…

Ms Sowinska wants the psychologists to make a recommendation about whether the children’s show should be broadcast on public television.

A 2004 study on the accessibility of mental health services in Poland found that the interval between being first assessed and getting mental health care was 12 weeks – much longer than all other European centres in previous studies.

A study on work difficulties in Poland published in 2006 found that mental and behavioural disorders were among the main causes of early inability to work.

And the government is ordering psychologists to assess Tinky Winky. It would be funny if it wasn’t so tragic.

Link to BBC News story.

The state of commercial neuroscience

NeuroInsights have released a report on the neurotechnology industry that uncovers the growing market for brain-based goods and services.

The 350 page report will set you back $4,500 (that’s almost $13 dollars a page!), but has been summarised by Zack Lynch, the company’s managing director, on his blog.

Some of the highlights include:

2006 venture capital investment in neurotechnology rose 7.5% to $1.666 billion

Neurotech industry revenues rose 10% in 2006 to $120.5 billion; this includes neuropharmaceutical revenues of $101 billion, neurodevice revenues of $4.5 billion, neurodiagnostic revenues of $15 billion

The Neurotech Index of publicly-traded neurotechnology companies was up 53% from its December 31, 2003 conception to March 31, 2006, outpacing the NASDAQ Biotech Index which gained 7% during the same period

In other words, the brain is big money, and it’s only likely to get bigger.

Needless to say, this makes us, the brain-owning public, equally blessed and cursed.

Commercial companies want us to spend our money on their products, meaning as well as developing technologies, they are likely to promote new ideas of well-being or ill-health to motivate us to use them.

This also tends to mean that problems faced by those with money (i.e. people in developed countries) get priority over the problems more typical of less developed countries.

So, treaments for diseases endemic in the developing world, like sleeping sickness, caused by trypanosoma infection and leading to brain disorder and eventual death, will likely be slow in coming.

However, we can be sure that some new advances in commercial neuroscience will be of huge benefit to many people.

The difficulty for us, and the investors, is that sometimes it is only clear which of the advances is significant with the benefit of hindsight.

Link to NeuroInsights industry report with free executive summary.
Link to Zack Lynch’s summary and comments.

Brain patch

An artist on Etsy is selling this wonderful iron-on brain patch based on an antique anatomical illustration.

For only $5 plus packing, you can get one of these delivered to your door and attached to, well, whatever you’d want a beautiful brain illustration attached to.

And if you can’t think of any reason you’d want a iron on brain patch, go see the drawing in more detail.

The cortex has obviously been subject to a little ‘artist license’, but it’s still a striking image.

Link to vintage medical anatomy illustration of the head and brain fabric patch.

Setting yourself back 30 years with hypnosis

Celebrity hypnotist Paul McKenna on BBC Radio 4’s music programme, Desert Island Discs:

“When you hear a song, back in say the 70s, the first time you heard it, it sounded absolutely fantastic and it’ll never sound like that again. So, I age regressed myself – I know this sounds a little unusual – and took myself back and then whacked on Sister Sledge, and it just sounded phenomenal. It sounded like it did years ago. It was fresh, with those amazing big disco drums…”

Paul McKenna, confusing the sound of drums with the sound of serious hypnosis researchers banging their heads against the wall.

Broadcasting from the silent land

If you’ve got half an hour, you could do a lot worse than spending it listening to ABC Radio National’s All in the Mind interview with neuropsychologist Dr Paul Broks, author of Into the Silent Land (ISBN 1843540347).

Broks writes in a part philosophical, part hallucinatory style, focusing on patients whose understanding and experience of the self has been disturbed by brain injury.

It’s one of my favourite books on neuropsychology, and Broks touches on many of its themes in the interview.

Broks has also written the play On Ego (ISBN 184002609X), which was based on part of the book, but which I found a little luke warm when I saw it and seemed to lack the originality of his writing.

However, he notes in the interview that he’s currently writing another play with the Royal Shakespeare Company about a woman who has intense religious experiences and temporal lobe epilepsy (the two often co-occur), which sounds immensely promising.

Broks will also be appearing at three events at the Sydney Writer’s Festival (two of which are free) so wander along if you happen to be in Sydney on May 31st or June 2nd.

Link to AITM interview with Paul Broks.

Guide to Psychology Blogs

PsyBlog has just published the first part of a guide to online psychology and neuroscience blogs, and says some jolly nice things about Mind Hacks in the process.

PsyBlog author Jeremy also highlights a few more of the many good online reads, but is too modest to mention himself, so I thought I’d pitch in an redress the balance.

Go see PsyBlog, it certainly deserves to be on the list.

Link to PsyBlog Guide to Psychology Blogs – Part 1.

Inkling on Human Nature

I’ve just discovered online science mag Inkling Magazine and noticed that their Human Nature section is full of great mind and brain articles.

Recent articles cover the safety of antidepressants for teenagers, the health risks of love and a brief interview with neuroscientist, author and stroke survivor Jill Bolte Taylor.

There’s a whole stack more, so have a browse and see what lights your candle.

Link to Inkling’s ‘Human Nature’ articles.