The truth about 'male' and 'female' brains

Research has shown that biology plays an important role in the nature of the brain. Photo / Getty Images

It was hailed as proof at last: for the first time, brain differences between the sexes had been found to be innate and identifiable in babies in the womb. Scientists at New York University Langone had successfully conducted scans of foetuses to look for changes in the connectivity of their growing brains. Supposedly their research had shown that biology plays an important role in their nature.

Had their evidence genuinely pointed to the existence of "male brains" and "female brains", this would have been quite some discovery. But, at the risk of disappointing all those who have seized on this "proof" with enthusiasm, I would contend it does no such thing.

As a neuroscientist who has long been working in this field, I agree this new dataset is exciting. Foetal brains quite clearly have not been exposed to any social or cultural influences, so studying them can be most revealing. Sadly in this case it is not.

Why? Well, first the brains being scanned in this study varied in gestational age from 25 to 39 weeks. This is a problem because a 25-week-old brain will be very different from a 39-week-old one. Although the researchers factored in gestational age in their analysis, it remains questionable how homogeneous the groups of brains they compared were. For example, in the age window 36 to 40 weeks, there were 35 males and only 17 females, which could very well have skewed the findings.

Still, it doesn't altogether surprise me that the study has generated such a stir. Scientific inquiry in this area has been ongoing for two centuries or so. Around the start of the 1800s, people considered the fact that women were financially, politically and socially inferior to men, took this as the status quo, and set about trying to find a reason. The explanation scientists hit on was there must be something different about men's and women's brains.

So began what I call the "hunt the difference" agenda. Over the years, studies have compared how groups of males perform certain tasks compared to groups of females, and report what kind of differences they've found. But what such research always fails to account for is the fact that these brains have been socialised, conditioned, and changed by the environment they've existed in. It rests on the premise that we can see there are differences between men and women, and that these differences must have been hard-wired from birth.

Arguing against this theory, as I have, does not always win you lots of friends. My work as a professor of cognitive neuroimaging, which has led me to appear on programmes including No More Boys and Girls, and to write a new book, The Gendered Brain, which seeks to dismantle the idea that one might exist, has led to my being called a "sex difference denier", a label that I fully reject. Of course there are biological differences between men and women, but what we need to understand is the additional part that environment plays – even from the first hours we spend in it.

The world makes a significant impression on our brains from the get-go, and even very young children have been exposed to cultural expectations and conditioning; their plastic, flexible minds affected by everything around them. It is virtually impossible to disentangle what is nature and what is nurture.

Any brain you look at will be different from any other, as each will be a product of the sum of its experiences. Our position in the family, what school we went to, what toys we played with, our occupations, our hobbies - all these things and more will play a part in shaping the brain, not just in infancy but right throughout our lives.

So often people look at gender gaps - the under-representation of women in science, for instance, or a man's superior spatial awareness - and try to claim this proves male brains are inherently different from women's. It may sound plausible, but the evidence isn't there to support it.

I would argue that any discernible differences found in men's brains compared to women's comes from a combination of differences in biology and experiences. So if a boy has grown up playing video games, this will shape the development of his brain, and may make him better at some tasks. Just as when you learn a language or a musical instrument, or do a Sudoku or crossword puzzle every day, neural pathways are strengthened when they're exercised, and also become weaker when such exercise ceases. It's known as the brain's plasticity, and it cannot be overlooked.

Ignoring this not only skews the scientific findings about brains, it can also have many repercussions socially. If you believe that the sexes have innately different skills, this logically extends to a belief that it is pointless to encourage people to break out of the boxes we've created for them. Thus the lack of women in science is excused by women's supposed inferior scientific ability – an argument that ignores the social context in which such things occur.

The ongoing discussions around transgender issues bring all these questions to the fore. When I say there's no such thing as an innately gendered brain, this does not play well with certain people.

Perhaps gender irrelevance is what we should be aiming for. Let's get away from the idea that your brain is in some way hard-wired to be female or male, to determine your skills and aptitudes, your role in society. Brains reflect the lives they have lived, not just the sex of their owners. The sooner we accept this reality, the more all of us can realise our potential.

*As told to Rosa Silverman