Louann Brizendine and the Neuroscience of the Female Brain

A few decades ago, the prevailing opinion among academic intellectuals in Western societies was that men and women were born with the same brains, but that the patriarchal socialization of children by cultural learning created stereotypical differences in male and female thought and behavior that favor male oppression of women. This suggested that social reformers could liberate women from patriarchal oppression by changing the environment of social learning to promote an androgynous society in which men and women would learn to think and act in virtually identical ways. But in recent decades, research in the biology of sex differences has challenged this position by showing how the biological nature of men and women differ in ways that are not explainable as products of social construction, and thus there is a natural limit to how far cultural changes can go in creating an androgynous society.

In Darwinian Natural Right and Darwinian Conservatism, I have drawn from that new research on the biology of sex differences to support my claim that men and women really are different by nature, but that those natural differences suggest not the superiority of men over women but the complementarity of male and female norms, in which the sometimes predatory propensities of men might be moderated by the civilizing prudence of women.

Most recently, advances in neuroscience have deepened our knowledge of how the differing neural and hormonal systems of men and women shape somewhat differing brains. Much of this new research come from improvements in brain-imaging technology. (Actually, there are some problems coming from reading too much into these brain images. But that's a post for another day.) Louann Brizendine's The Female Brain (New York: Morgan Road Books, 2006) surveys this research refuting the idea of the "unisex brain" and supporting the idea that female brains differ biologically from male brains.

The popular success of Brizendine's book comes from her combining impressive credentials and a lively writing style. She is a neuropsychiatrist at the University of California, San Francisco, and the founder of the Women's and Teen Girls' Mood and Hormone Clinic. She has advanced degrees in medicine and neurobiology from Yale and the University of California, Berkeley. She translates her expert knowledge into engaging writing by using anecdotes about the women she has counseled and by adopting a light and witty style. The main text of the book is written without any footnotes. But it's followed by 80 pages of citations and references to the scientific research supporting her claims.

Some of Brizendine's academic critics are put off by the cutesy style of the writing. For example, she identifies the hormone oxytocin as "fluffy, purring kitty; cuddly, nurturing, earth mother; the good witch Glinda in The Wizard of Oz; finds pleasure in helping and serving; sister to vasopressin (the male socializing hormone), sister to estrogen, friend of dopamine (another feel-good brain chemical" (xv). Of course, this is not the language of scientific research reports. But I can't see what's wrong with such language in a book written for a wide, popular audience, as long as the clever writing is not deceptive.

A more serious criticism is that sometimes the citations in the back of Brizendine's book don't clearly support the claims she makes in her main text. For example, in speaking about how women tend to be more talkative than men, she writes: "Men use about seven thousand words per day. Women use about twenty thousand" (14). Readers who wonder where she got these numbers might check the notes, where they discover that they come from a self-help book that cites no specific research to sustain this claim. Similarly, she writes: "Girls speak faster on average--250 words per minute versus 125 for typical males" (36). Readers who consult the notes will see a reference to an article about "speaking rates" among "20 pre-school stuttering and non-stuttering children and their mothers," which actually says nothing about differences between girls and boys in their speaking.

Here's one more example of the dubious connection between Brizendine's text and her citations. She says that one of the reasons why women have a better memory for emotional details than do men is that "a woman's amygdala is more easily activated by emotional nuance" (128). Her supporting reference is an article by Stephen Hamann, "Sex Differences in the Responses of the Human Amygdala". If you read the article, you will see that the conclusions of the article are much more complicated than what Brizendine reports. Accoring to Hamann's survey of the research, high amygdala activity is related to emotional memory for both man and women; but for men, it's the right amygdala, while for women its the left amygdala. And yet, Hamann notes, conscious ratings of emotional arousal correlate with the left amygdala for both men and women. Hamann then suggests that women's greater emotional memory might be a product of the fact that there is more overlap of brain regions for the women. Moreover, Hamann also shows that men manifest greater amygdala activity in response to visual sexual stimuli, in contrast to women. This is, I think, a typical example of how Brizendine often oversimplifies the research she's citing to make it sharper for her purposes.

Another example of this runs throughout the book, and it can be seen easily by an attentive reader, even without checking her citations. Oxytocin is one of the main protagonists in Brizendine's story. The Greek etymology of "oxytocin" denotes "quick delivery," because this hormone stimulates contractions of the uterus during child birth. Farmers inject their pregnant animals with oxytocin to induce delivery. But Brizendine speaks of oxytocin as associated not just with child birth but also with love, trust, orgasm, hugging, calming breast-feeding babies, and monogamous pair-bonding. But she never acknowledges what should be evident here to any careful reader: oxytocin does nothing by itself, because its diverse effects depend upon the diverse contexts in which it appears. This sort of causal complexity and contextuality is common in biology. But Brizendine tends to play it down in order to tell a clear, engaging story.

At the root of this problem is the big issue of nature versus nurture. Brizendine is sometimes confusing in how she approaches this issue. In her Introduction, for example, she says that female aptitudes are naturally "hardwired into the brains of women" (8). This suggests that she is a biological determinist, and it opens her up to all of the reasonable criticisms of such determinism. But then on the next page, she speaks of how the female brain is shaped "by a combination of nature and nurture" (9). Elsewhere in the book, she writes about how female propensities reflect the complex interaction of genes, hormones, life history, and social interactions (20, 27, 55, 68-69, 74, 100, 110, 133, 136-37, 147).

Here she comes close to the idea of "nurturing nature" that I lay out--in Darwinian Natural Right and Darwinian Conservatism--as an alternative to the false dichotomy between nature and nurture. To fully account for human nature, we need to see human thought and action as arising from the complex interaction of natural propensities, cultural traditions, and individual judgments. In fact, many of Brizendine's stories about the women she counsels illustrate that complexity of human experience.

This certainly holds true, for example, in what she says about the "mommy brain." Most women are naturally inclined to reproduction and child care, and that natural inclination is evident in their brains as evolved products of human evolution. But the specific expression of that natural propensity will vary according to the social circumstances of life and the individual judgments of the women making the best of their lives facing the sometimes difficult trade-offs presented to them.

As I indicated a few weeks ago in my post on Wendell Berry and E. O. Wilson, I agree with Berry that to understand the human mind we something more than the formula "mind = brain = machine." We need the more complex formula "mind = brain + body + world + local dwelling place + community + history," with "history" encompassing "the whole heritage of culture, language, memory, tools, and skills."

If one keeps in mind the emergent complexity of human life--and thus rejects any reductionist determinism--then one can read Brizendine's book as a rich survey of the female brain, the male brain, and the human brain shared by both men and women.