QED: Lopsided brains could make girls worse at maths

by Roger Highfield

The Sunday Telegraph: 18th April, 2004.

Have women got a head for maths? Apparently not. The highest ranks of mathematicians throng with male minds that are more comfortable with its abstract concepts of space, geometry and number.

Norway recently established the Abel Prize as the mathematical equivalent of Sweden's Nobel Prize. So far, there have been three winners, including Britain's Sir Michael Atiyah, who received the good news last month. All are men. No woman has ever won the Fields Medal either, a prestigious gong handed to mathematical prodigies aged under 40.

While women are often faster at calculation, men excel at mathematical reasoning and problem solving. Around the world people are trying to discover why, in research that ventures into territory which is beset by self-deception, prejudice and political correctness.

Studies of thousands of children by Prof Camilla Benbow of Vanderbilt university, Nashville, suggest that biology does shape mathematical destiny: while there is little difference overall, girls' scores are bunched around middle ability, while boys have a greater spread. Perhaps this difference is all in the mind. In recent years, various studies have concluded that sex differences are more than skin deep: the brains of men and women handle language and emotion in different ways, with differences in brain structure. This, in turn, may reflect our evolutionary past, and how men's brains were optimised to hunt and women's to gather.

Some speculate that exposure to the male sex hormone testosterone in the womb could sharpen mathematical skills by its selective action on the right half of the brain, enhancing the development of the right hemisphere's mental imagery skills, which come in handy for mathematical reasoning.

This dovetails with the findings of a study published a few days ago in the journal Neuropsychology by a team led by Professor Michael O'Boyle of the University of Melbourne, Australia. With colleagues in the US Army at Fort Benning, Georgia, they studied 60 right-handed young males, of whom 18 were mathematically gifted.

They found that the two halves of the brain co-operate better in the latter. Prof O'Boyle thinks that this is a signature of exceptional people. "Giftedness in maths, music or art may be the by-product of a brain that has functionally organised itself in a qualitatively different way than the usual left/right hemispheric asymmetry," he said. Such a brain, he believes, is marked by balanced and highly integrated contributions from both halves.

Although this did not address female ability directly, it hints that women are worse at maths because they tend to have lopsided brain organisation. Not everyone is convinced. Prof Brian Butterworth of the Institute of Cognitive Neuroscience in London points out that other work shows girls' brains are more symmetrical than boys'.

He believes that cultural pressures and variations in the quality of maths teaching are more likely to be responsible for "one of the most enduring maths myths" - that women are inferior. Decades ago, girls tended to be taught by non-specialist teachers, unlike boys. As a consequence of their better teaching, the boys did better but today - at least in GCSE mathematics - girls are on top, said Prof Butterworth.

Prof Benbow herself underlines the importance of cultural factors by pointing out that in China, where girls get more encouragement in mathematics, the number of gifted boys exceeds that of gifted girls by four to one, compared to 13 to one in America. There is evidence that girls have yet to reach their full mathematical potential. Prof Butterworth recently conducted the world's largest mathematics experiment on 18,000 people who passed through the Explore-at-Bristol science centre.

Women were quicker at carrying out a primitive, "instant judgment" type of maths, resting on a very basic numerical skill - estimating the numbers of dots up to three. Other insights may come from studies of top female mathematicians. There have been many, such as Theano, the 5th-century BC wife of Pythagoras, Ada Lovelace (1815-1852), who wrote the first computer program, and Mary Somerville (1780-1872), who gave her name to Somerville College, Oxford.

There is also, of course, Carol Vorderman, whose brain was recently scanned by Prof Butterworth's team. After rummaging through the neurons of one of the few TV stars more famous for her brains than her pretty face, he marvelled at the size of her hippocampus, a region involved in memory and navigation. But his colleagues are still analysing the data. Science will have to wait a little longer to find out if her brain can help reveal whether male mathematical superiority is real.