“Reports trumpeting basic differences between male and female brains are biological determinism at its most trivial, says the science writer of the year”
Science Writer of the Year, Robin McKie, has written a long article refuting the latest Brain Sex! study reported in the mainstream press at the end of last year; the whole thing is well worth a read, below are the highlights:
As I have said, I have read this sort of thing before. I didn’t believe it then and I don’t believe it now. It is biological determinism at its silly, trivial worst. Yes, men and women probably do have differently wired brains, but there is little convincing evidence to suggest these variations are caused by anything other than cultural factors. Males develop improved spatial skills not because of an innate superiority but because they are expected and encouraged to be strong at sport, which requires expertise at catching and throwing. Similarly, it is anticipated that girls will be more emotional and talkative, and so their verbal skills are emphasised by teachers and parents. As the years pass, these different lifestyles produce variations in brain wiring – which is a lot more plastic than most biological determinists realise. This possibility was simply not addressed by Verma and her team.
Equally, when gender differences are uncovered by researchers they are frequently found to be trivial, a point made by Robert Plomin, a professor of behavioural genetics at London’s Institute of Psychiatry, whose studies have found that a mere 3% of the variation in young children’s verbal development is due to their gender. “If you map the distribution of scores for verbal skills of boys and of girls, you get two graphs that overlap so much you would need a very fine pencil indeed to show the difference between them. Yet people ignore this huge similarity between boys and girls and instead exaggerate wildly the tiny difference between them. It drives me wild.”
A major problem is the lack of consistent work in the field, a point stressed to me in 2005 – during an earlier outbreak of brain-gender difference stories – by Professor Steve Jones, a geneticist at University College London, and author of Y: The Descent of Men. “Researching my book, I discovered there was no consensus at all about the science [of gender and brain structure],” he told me. “There were studies that said completely contradictory things about male and female brains. That means you can pick whatever study you like and build a thesis around it. The whole field is like that. It is very subjective. That doesn’t mean there are no differences between the brains of the sexes, but we should take care not to exaggerate them.”
The field suffers because it is bedevilled by its extraordinary complexity. The human brain is a vast, convoluted edifice and scientists are only now beginning to develop adequate tools to explore it. The use of diffusion tensor imaging by Verma’s team was an important breakthrough, it should be noted. The trouble is, once more, those involved were rash in their interpretations of their own work.
“This study contains some important data but it has been badly overhyped and the authors must take some of the blame,” says Professor Dorothy Bishop, of Oxford University. “They talk as if there is a typical male and a typical female brain – they even provide a diagram – but they ignore the fact that there is a great deal of variation within the sexes in terms of brain structure. You simply cannot say there is a male brain and a female brain.”
Even more critical is Marco Catani, of London’s Institute of Psychiatry. “The study’s main conclusions about possible cognitive differences between males and females are not supported by the findings of the study. A link between anatomical differences and cognitive functions should be demonstrated and the authors have not done so. They simply have no idea of how these differences in anatomy translate into cognitive attitudes. So the main conclusion of the study is purely speculative.”