Is a dash of autism and an ability to turn from the world essential for scientific success? Melanie Newman reports.
A DVD of trains with faces stuck on their fronts is the intriguing new product of Simon Baron-Cohen's team at Cambridge University.
Every child in Britain diagnosed with autism is to receive the DVD for free in an attempt to use their interest in vehicles to improve their social skills.
As Professor Baron-Cohen explained in a lecture at Kent University last week, the simple idea builds on his key theory about autism: that those with autistic conditions have a keen interest in and talent for "systemising". Although they lack the empathising capability necessary for easy social communication, they are better than average at analysing and building systems - whether mechanical, natural or abstract.
In his talk, which asked whether autism and scientific talent are linked, Professor Baron-Cohen explained that he had designed a test for autistic traits, such as preferring to do things alone rather than with others, or to do things in the same way over and over. His results show that the traits are more likely to be found in scientists than in the general population.
In his speech at Kent, Professor Baron-Cohen cited Hans Asperger, the paediatrician who identified the eponymous syndrome. Asperger suggested that "for success in science... a dash of autism is essential... the necessary ingredients may be an ability to turn away from the everyday world".
"Autistic traits and scientific talent are linked," Professor Baron-Cohen said. "I don't like the term 'autistic spectrum disorder'. While the condition does involve disability it clearly involves areas of strength."
Narrow interests and obsessions may be a sign of strong "systemising" ability, he postulated.
Informing Professor Baron-Cohen's hypotheses on autism is his theory that on average males and females are cognitively different, and that those with autism use an extreme type of male thinking. Autistic traits, like autism itself, are more common in men than in women.
Professor Baron-Cohen has designed a series of tests he believes show that autism, a person's sex and scientific talent are interlinked.
Scientists and autistic people score higher than the general population on the professor's "systemising quotient" test, which asks whether respondents agree or disagree with statements such as "When I listen to a piece of music I always notice the way it's structured" and "When I learn a language I become intrigued by its grammatical rules". Men also score higher than women on this test.
Women score higher on the "empathy quotient" test, which asks whether they agree or disagree with statements such as "I can usually appreciate the other person's viewpoint, even if I don't agree with it." Scientists and those with autism score lower on this test than the general population and men score lower than women.
On the basis of these tests, Professor Baron-Cohen has proposed a classification of five brain types: male, female, extreme male - which is likely to be autistic - extreme female and "balanced". He points out that some women have a "male brain", some men have a "female brain" and some people have a "balanced brain", so no assumption should be made when judging an individual's suitability for a job. But he does believe that the differences may account for the gender disparities in certain occupations.
In his book The Essential Difference , he writes: "People with the female brain make the most wonderful counsellors, primary school teachers, nurses and carers. Each of these professions requires excellent empathising skills." People with the male brain - and systemising skills - "make the most excellent scientists, engineers and mechanics".
Not everyone agrees that enhanced "systemising" skills necessarily make for a good scientist. Jenny Koenig, chair of the Cambridge Association for Women in Science and Engineering, said: "Good and successful scientists need to be able to do a lot more than systemise. Scientists need to be creative, show perseverance, work well in a team, be able to understand other points of view, think laterally and communicate well."
Philippa Browning, a reader in physics and astronomy at Manchester University and a member of the Women in Physics committee at the Institute of Physics, said that society and culture play a major role.
"We know that the proportion of women working as physicists varies widely from one country to another. For example, women's representation is much higher in France than in Germany," she said. "It seems much more natural to attribute these differences to the cultural and societal factors than to suppose that more women in France have male brains."
Professor Baron-Cohen admits he has not studied how his test results vary between nations and cultures but says he is fully aware that discrimination exists.
"I'm all for change in society. But suppose you removed any barriers that might be obstacles to gender equality, would the sexes end up equally represented in subjects such as physics and mathematics? My argument is that biological differences may influence interests."
Despite his references to "male and female brains", which suggest differences in neural structure, Professor Baron-Cohen is talking only about cognitive profiles.
Lucy Wyatt, head of Sheffield University's department of applied mathematics, believes research such as Professor Baron-Cohen's on the nature of the human brain and its variability is useful but criticises his references to "male" and "female" brains.
"I think it inevitably reinforces stereotypes," Professor Wyatt said. "If there really is a scientific basis for different brain types, let's refer to them by their type."
Wendy Faulkner, a reader in technology studies at Edinburgh University, agreed. "The labels 'male/female brains' do enter consciousness. They then serve to 'naturalise' presumed differences in how much women and men care about people," she said. "Such stereotypes are the basis of inequality."
The Autism Research Centre is currently researching the neural basis of the five brain types using MRI scans to map brain activity during different tasks. A pilot study has shown that males and females showed different patterns while performing certain tasks.
Another Cambridge study suggests a relationship between autistic traits and higher levels of foetal testosterone, while a genetic association study is looking for a "maths gene". The team is examining specific genes with a role in neural development or function to see if elements of the genes differ in their frequency between mathematicians and non-mathematicians.
Professor Baron-Cohen told the Kent conference of a "large body of literature" on sex differences in the general population. However, an equally large body of evidence suggests sex differences in brain structure and function do not affect scientific ability.
The Committee on Maximizing the Potential of Women in Academic Science and Engineering set up by the National Academy of Sciences, the National Academy of Engineering and the Institute of Medicine in the US issued a report, Beyond Bias and Barriers , in September 2006.
After an exhaustive review of studies of brain structure and function, hormonal modulation of performance, human cognitive development and human evolution, the report concluded there was no evidence that biological differences accounted for under-representation of women academics in science and mathematics.
The report did find, however, substantial evidence from cognitive psychology research showing that most men and women carry prejudices of which they are unaware but which influence their evaluations of other people and their work.
SHADES OF GREY MATTER
British and American readers need different incentives to read about women's grey matter, if the cover art on the two editions of neuropsychiatrist Louann Brizendine's The Female Brain is anything to go by.
In a nod to women's perceived superiority in communication, the American version shows a tangled mass of phone leads.
The British version is proportionately smaller and shaped like a handbag, bursting with a mobile phone, a lipstick, headphones and an image of a bride and groom. "Sassy, witty, reassuring and great fun," proclaims the UK cover, while the American cover is blurbless.
The book suggests that fewer women reach the top of their fields in science and engineering because they are by nature more sociable.
It proved controversial in the US after Mark Liberman, writing in The Boston Globe , accused Professor Brizendine of using a self-help guru as a source for key statistics.