The difference between men’s and women’s brains, explained

Is there a difference between men’s and women’s brains?

The question of whether the brain has a sex has occupied the scientific community for decades. A study recently published in the journal PNAS provides further insight into the matter, since its authors claim that brain organisation patterns differ according to biological sex.

The difference between men’s and women’s brains, explained

Researchers from Stanford University reached this conclusion by taking advantage of recent advances in artificial intelligence (AI). They developed a deep neural network model that they taught to classify functional MRI data, to determine whether it was able to distinguish between men’s and women’s brains.

After training this AI on around a thousand cases, the research team then presented it with functional MRI scans of some 1,500 people of both sexes, aged between 20 and 35. The investigators found that, in 90% of cases, this artificial intelligence model was able to distinguish between men’s and women’s brains.

The academics found that the artificial intelligence analysed the very organisation of the brain, particularly that of the striatum, the limbic system and the “default mode” brain network, to differentiate between the different brain scans. “This is a very strong piece of evidence that sex is a robust determinant of human brain organisation,” study co-author, Vinod Menon, said in a news release.

The danger of stereotyping

To extend their research, Vinod Menon and colleagues set out to test their deep neural network model on two other cohorts, without additional training. In particular, they wanted to see whether this artificial intelligence model would be able to predict the results of individuals of both sexes on certain cognitive tasks. This proved to be the case, prompting the scientists to reaffirm their hypothesis that the functional characteristics of men’s and women’s brains have “significant behavioural implications.”

But the conclusions of this study should be interpreted with caution, despite its rigorous methodology. The authors themselves note that they are unable to state with certainty whether the brain differences they observed “arise early in life or may be driven by hormonal differences or the different societal circumstances that men and women may be more likely to encounter.”

Currently, the scientific community largely agrees that the intellectual aptitudes of men and women are not genetically programmed into their brains. The cerebral differences observed between the sexes do not allow generalisations to be made, which puts an end to sexist preconceptions. For example, there is no evidence to suggest that girls are “naturally” less gifted than boys in scientific subjects. Advances in neurobiology have established that every brain is different. The variations observed between individuals are not simply a question of sex, but rather of cerebral plasticity.

This story is published via AFP Relaxnews.