Differences in the brain wiring of men and women

Major science journals issue science journalists with press releases about papers that they think will make a splash and give them embargoed advance copies of the articles so that journalists can research them and write their articles with the understanding that the articles won’t be published until the journal is released.

I have learned to be a little wary of news stories that either flatly contradict established knowledge or support common prejudices. Very often these are tentative and speculative results that in the original papers are hedged with caveats (small sample sizes, limited range, lack of proper controls) but those are stripped away in the news reports and the press releases that accompany them.

For this reason, I was a little cautious about a new paper that found that the brains of men and women were wired differently, with men’s brains wired more in the front-to-back direction while the women’s were wired more between the left and right hemispheres. From the abstract:

In all supratentorial regions, males had greater within-hemispheric connectivity, as well as enhanced modularity and transitivity, whereas between-hemispheric connectivity and cross-module participation predominated in females… Overall, the results suggest that male brains are structured to facilitate connectivity between perception and coordinated action, whereas female brains are designed to facilitate communication between analytical and intuitive processing modes.

This is undoubtedly intriguing. But is it a real effect or a product of some other unmeasured and unaccounted for factor? But that lack of knowledge did not prevent people from indulging in all manner of speculations.

Ragini Verma, a researcher at the University of Pennsylvania, said the greatest surprise was how much the findings supported old stereotypes, with men’s brains apparently wired more for perception and co-ordinated actions, and women’s for social skills and memory, making them better equipped for multitasking.

“If you look at functional studies, the left of the brain is more for logical thinking, the right of the brain is for more intuitive thinking. So if there’s a task that involves doing both of those things, it would seem that women are hardwired to do those better,” Verma said. “Women are better at intuitive thinking. Women are better at remembering things. When you talk, women are more emotionally involved – they will listen more.”

She added: “I was surprised that it matched a lot of the stereotypes that we think we have in our heads. If I wanted to go to a chef or a hairstylist, they are mainly men.”

This kind of extrapolation makes me uneasy. So I waited a bit to see if there were more mundane possibilities. Neuroskeptic came up with two alternative hypotheses other than brain wiring that could explain the data: head motion and brain size, neither of which were controlled for in the original study.

This is not to criticize the original study. Initial investigations are necessarily limited and incomplete. It is just meant to warn people to not take too seriously the speculations in the media about new scientific discoveries. In science, it takes a while for all avenues to be explored and for a consensus to emerge.


  1. says

    Robin McKie has an interesting reply:

    “Why it’s time for brain science to ditch the ‘Venus and Mars’ cliche”


    Excerpt about the technique used, diffusion tensor imaging:
    “DTI provides only indirect measures of structural connectivity and is, therefore, different from the well validated microscopic techniques that show the real anatomy of axonal connections,” says Marco Catani, of London’s Institute of Psychiatry. “Images of the brain derived from diffusion tensor MRI should not be equated to real connections and results should always be interpreted with extreme caution. …

  2. mnb0 says

    “the speculations in the media about new scientific discoveries”
    I have long ago stopped to take the speculations seriously, but remain intrigued by such researches.

  3. smrnda says

    I get a bit irritated at the whole ‘intuitive thinking’ deal, as I have yet to find any real definition of ‘intuitive thinking’ that contrasts it meaningfully with ‘rational thinking’ or ‘analytical thinking.’ I tend to find people label an approach ‘intuitive’ if it doesn’t seem to be the most straightforward approach to a task they would come up with. the terms used to differentiate between different types of thinking strike me as meaningless.

    Comments like ‘when you talk to women, they seem much more emotionally involved’ strike me as nothing but parading around confirmation bias as proof of its own existence, or a comment that social norms are such that women are expected to show more emotion and expression when communicating. As a woman who is fairly deadpan by the normal standards of the US, I’ve had people read me as expressing some negative emotion when I really feel I’m showing nothing at all.

  4. northstar says

    >>She added: “I was surprised that it matched a lot of the stereotypes that we think we have in our heads. If I wanted to go to a chef or a hairstylist, they are mainly men.”<<

    Seriously? A gay man, maybe. There's no freakin' way I'd let a straight guy do my hair. Now *there's* a topic to study. And a chef? Is she telling me men are better cooks?

    Seems to me, if your results seem to mysteriously match your mental stereotypes, it might be time to start looking to see if your perceptions are clouding your conclusions.

  5. Nathair says

    Seriously? A gay man, maybe. There’s no freakin’ way I’d let a straight guy do my hair.

    Seems to me, if your results seem to mysteriously match your mental stereotypes, it might be time to start looking to see if your perceptions are clouding your conclusions.

    And another irony meter bites the dust.

  6. lanir says

    People like to believe things that agree with or complement their world view and their opinions. It’s annoying to have to learn the biases of ignorant jerks as though they were important just so you can take in news with a reasonable BS filter.

  7. northstar says

    Nathair, I’m not publishing my perceptions as though they are science, though. Big difference.

  8. thewhollynone says

    Oh, this is such a silly argument! Of course, female brains and male brains are different– on average, and not to say that there aren’t a few outliers. Everybody knows that; it’s a self-evident truth. And everybody knows deep down that the female brain is far superior to the male brain; goodness, that’s why females have to do all the hard work and to make all the really tough decisions to keep our species surviving, functioning, and expanding. Females have to decide whose male sperm gets to sire the next generation; females have to care for our most precious resource, the children, often against almost overwhelming odds; females have to keep the family healthy by doing constant germ and vermin control (known in modern parlance as “housework”); females have to use incredible ingenuity to provide a constant supply of food and water for the family because people don’t eat in the long run, you know; people eat every day; females have to cultivate the social skills necessary to keeping the peace among squabblers by knowing how to divide up the food and water so that everyone gets what he or she needs at the time. History has shown it to be obvious that male brains are totally incapable of that level of thinking, in general, on the grand scale, although there have been a very few exceptional individuals. But male brains have their uses in the proper places; after all somebody has to decide who wins the Super Bowl, who gets the Suez Canal. and who gets to be first on the moon, and females are too busy to bother their brains with such trivia.

Leave a Reply

Your email address will not be published. Required fields are marked *