Biological Determinism and the Never-Ending Quest for Gender Differences

Let’s face it: Books on gender differences sell. There appears to be no end to the public hunger for scientific evidence that confirms men and women to be of different species. This hunger—not large meaningful gender differences in brains or behavior—must be acknowledged as the impetus for The Female Brain. Louann Brizendine, a psychiatrist with an education from the University of California at Berkeley, Harvard, and Yale, theorizes that gender differences in behavior are directly caused by innate brain differences. She integrates stories of her clients from the Women’s and Teen Girls’ Mood and Hormone Clinic at the University of California at San Francisco with anecdotes from her own life and a review of animal and human psychological research. These sources paint an uncomplicated picture of gender differences and the neuroendocrine forces behind them. Many can identify with the female clients she describes: teenagers with mood swings and mothers stressed from child care and work demands. The book follows a life-span organization, progressing from “The Birth of the Female Brain” to “The Mature Female Brain,” which makes it accessible. To an educated but naı̈ve reader, this book has it all. To a scientist, this book is inaccurate and disappointing. The Female Brain would not likely survive the peer-review process (in fact, Brizendine has not published a first-author piece in a peerreviewed journal, despite her impressive credentials). The primary flaw is in the careless research behind her theory. I first noticed this problem in the introduction, where I saw a reference to my research on gender differences in childhood temperament (ElseQuest, Hyde, Goldsmith, & Van Hulle, 2006). I was intrigued to see it cited because it was irrelevant to the topic, a statement about the “astonishing array of structural, chemical, genetic, hormonal, and functional brain differences between women and men” (p. 4). Then I saw this study cited another 10 times—again, with no mention of childhood temperament in sight. This kind of error—citing unrelated research—occurs regularly. Brizendine frequently misrepresents or misunderstands research that is related to her topic to maintain the simple plotline. Further, there are numerous times when strong claims about hormones causing behavior are not supported by scientific research. The language is often inappropriate and unscientific—she writes of “biological truths,” female brains “marinating in estrogen,” and “innate differences” between the genders. At times, descriptions of scientific research on nonhuman animals are so imprecise that the reader would think the data were collected in humans. Moreover, Brizendine overgeneralizes nonhuman animal research to support her theory, even when findings from human research contrast with such generalizations. Conjectures about causal links are made without being identified as simple speculation. In several cases, she ignores research that directly and clearly refutes her speculation. Errors and oversights such as these are dangerous, particularly when consumed by a naı̈ve reader. Grossly exaggerating small gender differences, The Female Brain promotes the stereotype that men and women really are from different planets. There is no discussion of effect sizes, overlapping distributions, or within-group differences, despite abundant evidence that many psychological gender differences are small and that there is much variability within genders (Hyde, 2005). In reference to adolescent girls’ body image concerns, she claims, “They [girls] would be obsessing over whether or not boys thought they looked good because their hormones create the reality in their brains that being attractive to boys is the most important thing” (p. 32). Brizendine wholly rejects the idea that socialization and culture contribute to gender differences. According to Brizendine, adolescent gender differences in depression are the direct result of pubertal sex hormones and genetics. On the handful of occasions when Brizendine mentions socialization, she does so only to say it is irrelevant. This book maintains that neuroendocrine factors directly cause psychological gender differences. Her review of the research is unbalanced, and it is difficult to see this work as anything other than reductionist biological determinism that serves to promote gender-role stereotypes. Feminists will also be dismayed to see that Brizendine ignores many dimensions of diversity. The work supports heterosexism by implying that all women are heterosexual and neglecting to address the experiences of lesbians. Transgender or intersex individuals are not discussed, though surely their “biological reality” differs in some interesting way. She does not discuss ethnicity or socioeconomic factors, though they are clearly relevant to psychological gender differences. This type of omission is surprising, given that Brizendine accurately notes how women were long excluded from psychological research because of their assumed deviation from the male norm. Yet, discussing women’s diversity would complicate Brizendine’s theory. It is unfortunate that publication standards are not more rigorous when one can reach such a broad audience with a popular press book. As scholars, we have a responsibility to educate others so that they can be empowered to make informed choices. Brizendine genuinely feels she contributes in this way; yet, given the critical flaws in The Female Brain, this book could do more harm than good by misinforming women and men about psychological gender differences. In light of the media attention given to this book, it is important that we continue our efforts to educate others about the more complicated story of gender that is not told in The Female Brain—at last exposing the work to careful peer review.