"... for nothing terrifies the average man so much as a touch of science which he does not understand. And nothing gives a shallow-minded individual so much importance as to when he quotes a little false biology."
~ Woman Suffrage (1907) by Arnold Harris Mathew

This past week marked the 90th anniversary of the ratification of the 19th Amendment to the US Constitution, which granted women the right to vote. The right to vote was only achieved after decades of work by supporters of women's suffrage. The "false biology" Mathew refers to in the quote above is the belief that the anatomy of women's brains made them intellectually inferior to men, a claim that was used to argue that women were mentally unsuited to vote. As Mathew points out¹, the latest scientific evidence did not find any significant gender difference in brain size or overall intelligence.

But even when women and men were considered to have similar levels of intelligence, it was argued that gender differences in brain anatomy showed that men and women have different types of intelligence:

For example, prominent phrenologist² Jessie Allen Fowler proposed:

Those parts [of the brain] which are most extensively developed in man are the seat of the intellectual attributes, creative and volitional, as opposed to the emotional and sensatory, which have their seat in the posterior and lower region; and those parts of the brain which are most extensively developed in woman are the seat of the emotional, domestic and affectionate attributes.

Thus man, as a result of this brain development of a differentiated character, shows a mind endowed with judgment, creative power and philosophic reasoning ability; and woman, on the other hand, shows an insight into the domestic relations, home life, and the social well being of mankind.

This does not mean that man has no affection and woman has no reasoning powers, but that the above named attributes predominate as a prerogative in each sex.

~ Brain Roofs and Porticos (1913), pp. 69-70

Fowler's conclusions about the gendered brain - that women are good at understanding emotions and men are good at problem solving - aren't too different from those published nearly a century later.  And while I think it's easy to dismiss Fowler's analysis of gender differences as  stereotypes dressed up as science³, current popular science books and articles

often cite recent scientific studies that presumably are more experimentally solid than phrenological skull measurements.

It turns out that even those books that appear to be scientific on the surface may distort the science to emphasize gender differences and downplay the similarities between men and women.

As Mark Liberman at Language Log has pointed out in his analysis of the misrepresentations of science in Louann Brizendine's book The Female Brain, the issue is not that there aren't differences between men and women, but that those differences are often misleadingly exaggerated:

There certainly are psychological and neurological differences between men and women, sometimes big ones. But even when they aren't promoting their ideas on the basis of "facts" that are apparently false, authors like Sax and Brizendine use a set of rhetorical tricks that tend to make sex differences seem bigger and more consequential than they really are. You can do it too, if you want -- just choose phenomena that emphasize differences, leaving out the ones where the sexes are more similar; pick studies that find stereotypic differences, leaving out the ones whose results disagree; and in all cases, talk and write as if (even relatively small) differences in group averages were essential characteristics of every member of each group.

(read Liberman's whole post if you haven't already)

Australian psychologist Cordelia Fine has looked more deeply at the issue in her recently published book, Delusions of Gender: How Our Minds, Society and Neurosexism Create Difference.  While I haven't read it yet, at least part of it appears to expand on Fine's 2008 paper in the journal Neuroethics - "Will Working Mothers' Brains Explode? The Popular New Genre of Neurosexism" (pdf).

In that article, she suggests why so many people find the claims that there are significant gender differences in brain function appealing:

What, exactly, is the draw of gender stereotypes dressed up as neuroscience? For men, perpetuation of the idea that they lack women’s hard-wired empathizing skills is a small price to pay for license to lay claim to more valued and potentially profitable psychological advantages. According to another popular book about gender difference, The Essential Difference [1], “[t]he female brain is predominantly hard-wired for empathy. The male brain is  predominantly hard-wired for understanding and building systems.” (p.1). As Levy [16] notes, this translates to the idea that “on average, women’s intelligence is best employed in putting people at their ease, while the men get on with understanding the world and building and repairing the things we need in it.” (pp. 319–320). Levy adds, “[t]his is no basis for equality. It is not an accident that there is no Nobel Prize for making people feel included.” (p. 323).

Fine suggests that women may use the information to rationalize the status-quo. For more about Delusions of Gender, see the interview with Fine in USA Today's Science Fair blog, the review post at Language Log, and the article about Fine's book in the Guardian.

So if there are indeed differences in the average male and female brain, and many men and women find those differences appealing, why is highlighting those differences a problem?

Even thought we may not consciously acknowledge gender stereotypes, they can unconsciously affect the way we perceive both ourselves and others. For example, women business leaders who conform to female stereotypes are often perceived as less competent, while those who do not conform are considered "too tough" or "too angry". Similarly a recent study by physicist Amy Bug showed that a physics lecture made by male actors received significantly higher performance ratings from male students than the identical lecture given by female actors.  Such biases are difficult to counter, since most people don't consciously realize they have them (you can try the Implicit Association Test, to assess your own unconscious biases).

It's has also been shown that just the knowledge of a negative stereotype about the group in which one belongs, can have a detrimental effect on performance.  For an examples of the effects of "stereotype threat", see Christina Agapakis's post explaining how cultural stereotypes about math ability appear to affect test scores.

Even if there are significant differences "on average" between male and female brains, such averages tell us nothing about a particular individual's abilities, aptitudes or interests. I'm not much of a stereotypical "girly" girl - don't care for chatting on the phone, have had the same hair style for a decade and enjoy science. On the other hand I tend to be soft spoken, and like watching Project Runway and cooking shows, and I think of myself as sentimental and sympathetic. Most women and men I know also have a mix of stereotypical "masculine" and "feminine" preferences and behaviors. Pop culture books that misrepresent neuroscience studies to suggest that only stereotypical behavior is "normal" or "natural" do us all a disservice.

I'm looking forward to voting in November.

Top photo: Image from the Library of Congress's Bain Collection on Flickr

Middle images: Illustrations from Jessie Allen Fowler's Brain Roofs and Porticos

Bottom image: National Institute of Biomedical Imaging and Bioengineering, Image courtesy of Dr. Paul Thompson, University of California, Los Angeles.