Brain-sex differences a myth?

This was originally going to be a comment over at Athena’s blog, specifically in response to this post (where she expresses her frustration at not being listened to), but I realized I was dangerously close to a threadjack and potential flamewar, so I decided to move my comment here.

here’s a metric ton of links from Mark Lieberman debunking “the brain-sex gospel” (I’m not sure if that’s Lieberman’s phrase or not): the links are at the bottom of this post.

A single post that lays out Lieberman’s point of contention with the specific meme that “studies show that women speak more words than men in a day” is this one. Here’s a quote that summarizes his argument:

Louann Brizendine’s book The Female Brain, published last August, featured a number of striking quantitative assertions about sex differences in communication. The jacket blurb claimed “A woman uses about 20,000 words per day while a man uses about 7,000”, while the text (p. 14) gave the same numbers in the other order: “Men use about seven thousand words per day. Women use about twenty thousand.” Dr. Brizendine gives a set of references in her end-notes, but none of them support those numbers. In fact, no study of any sort has ever measured any numbers at all like these, as far as I’ve been able to find.

What are the facts about sex and talkativeness? There’s an enormous amount of individual variation, and each individual talks more or less depending on mood and context. Against this background of variation, many studies have measured how much women talk, on average, compared to how much men talk, on average. The differences that they find between men and women as groups have always been small compared to the differences among men as individuals or among women as individuals. And more often than not, these small group differences actually show men talking a bit more than women do. For additional details, see the links at the end of this post.

Even more links at the bottom of that particular post. Elsewhere he links the idea that there are gender-based differences in brain structure to the debunked (as far as I’m concerned: see Stephen Jay Gould’s “The Measure of a Man”) idea that there are “race”-based brain differences, in that both ideas are supported by nothing more than prejudice, rather than science. The reason the gender-based idea is more “popular” is because its proponents have couched their arguments in terms that appeal to feminist prejudices, as well.

I’m simply summarizing someone else’s views. I understand that massively quoting one source does not a scientific argument make, and could be characterized as the logical fallacy of appeal to authority, so if you disagree with the idea I’m presenting above, I’m not going to spend a lot of time arguing against you. I’m not an authority on gender or language, and I’ll admit right now that Lieberman’s idea feeds my bias that we’re all more similar than we are different; men, women, dark skin, light skin, tall, short, young, old. Why focus on the tiny percentage that is different? Why group people by the basis of superficial examples of natural genetic and historical variation? At least, that’s my opinion and my underlying assumption.

Feel free to challenge my assumptions, though. Nothing is more entertaining or liberating.