The Female Brain

The Female Brain is a book by Louann Brizendine, M.D. whose main thesis is that women’s behavior is radically different from that of men due to hormonal differences. Brizendine argues that the human female brain is affected by the following hormones: estrogen, progesterone, testosterone, (oxytocin), neurotransmitters (dopamine, serotonin), and difference in architecture of the brain (prefrontal cortex, hypothalamus, amygdale) that regulates such hormones and neurotransmitters. These hormones have a life cycle of their own defining specific passages in a women's life including, puberty, and menopause. The book was not factchecked, and the author culled some of her supportive statistics from self-help gurus who seem to have fabricated them (see Fact-checking the Female Brain). At the beginning of the book, the author created a table that depicts her views on human female neuropsychological development. A summary of this table is depicted below.

Brizendine book includes seven chapters. Each chapter is dedicated to either a specific slice of a woman’s life such as puberty, motherhood, and menopause or a specific dimension of a women’s emotional life such as feelings, love & trust, and sex. The book also includes three interesting appendices on hormone therapy, postpartum depression, and sexual orientation.

Main differences between the female and male brains
The author sees neurological differences between men and women as significant enough that it makes sense to speak of a "female brain" and a "male brain". She believes that the former has larger resources dedicated to communication and emotion, which she deduces from the fact that the female hippocampus is larger than the male, and that the "female brain" has 11% more neurons dedicated to language. Testosterone level is a differentiator between male and female as it is so much lower in women. As a result, the author sees women as being cooperative, less competitive, less aggressive, more concerned with emotion of others, and more focused on the group than the self alone. She sees men as being 20 times more aggressive.

According to Brizendine, during their teens the differentiation between the female and male brain is significant. Girls, according to the author, speak faster and two to three times as much as boys. She argues that girls need social connection and ongoing communication opportunities. When those are lacking, a girl after puberty is twice as vulnerable as a boy to depression, according to Brizendine. On the other hand, because of lesser developed communication skills boys are a lot more at risk for autism.

The impact of motherhood on the female brain
Per the author, a woman's brain is altered forever after motherhood to enhance the survival of her children. The author analyzes the related metamorphosis of the women's brain in technical detail at the hormonal level.

Love and Sex
The author also addresses at length love and sex. Her findings based on neuroscience confirm some the clichés we have that women look for economic stability and loyalty in men. While men look for sexiness, women's focus is nesting. Men's is fertility. However, Brizendine indicates things get more complex. Women do want long-term relationship with loyal and caring providers. However, they occasionally do reproduce with a philanderer who appears to have superior genes. Brizendine states that 10% of children are fathered by such philanderers without the his knowledge. Superior genes are characteristics of males who have greater symmetry in their body and face. In plain English, this means men who are more handsome. Apparently, this has been confirmed by countless studies. Also, interestingly enough, the loyalty of a male seems incredibly predetermined by the length of a certain gene (which influences the manufacture of vasopressin receptors)--the longer, the more loyal.

Menopause
The chapter on menopause and the mature women suggests that marriages go through a rebalancing of the roles if they are to survive. The changing hormonal balance, including the drop off in estrogen, triggers a marked reduction in nurturing behavior. Nurturing children and husband becomes really tasking. Postmenopausal women substitute nurturing with self-actualization. This is especially pronounced if the kids are out of college and the husband is retired and expects three meals a day. The terms of the marriage need to be renegotiated if the marriage is to survive. Counter to the public's perception it is women who initiate 65% of the divorces among couples over 50.

The Lawrence Summers issue
Early in the book Brizendine addresses Lawrence Summers' remark that women are underrepresented in mathematics and scientific fields because when comparing men vs. women, even though their average ability may be the same, women's variability (or standard deviation) was lower. Thus, few women reached the top echelons of those fields. Brizendine rebuts Summers by indicating that girls' and boys' ability and variability are the same through their teen years. Brizendine states that fewer women reach the top echelon in the mentioned fields because their brain wiring makes them more social and they do not seek lonesome scientific pursuits.

Supportive authors

 * Deborah Tannen. 'A Brain of One's Own'. Washington Post August 20, 2006.
 * Daniel Goleman author of Emotional Intelligence.
 * Christiane Northrup, M.D., author of The Wisdom of Menopause.

Criticism of the book
Nature ' s review of the book was quite critical, calling The Female Brain a "melodrama" "riddled with scientific errors" and "fail[ing] to meet even the most basic standards of scientific accuracy and balance" Furthermore, the authors state that: Human sex differences are elevated almost to the point of creating different species, yet virtually all differences in brain structure, and most differences in behaviour, are characterized by small average differences and a great deal of male–female overlap at the individual level.

David H. Peterzell, a Cognitive and Clinical psychologist, expressed numerous reservations about the book. One of his main objections is that Brizendine conveys certainty about differences in brain structure, including differences in hormonal levels and behavior. Peterzell argues that this is weak science and that the author should have instead studied the relationship between brain structure and behavior from a statistical standpoint, in order to uncover correlations between the two. But, as he argues, correlations are not certainties. Peterzell was also uncomfortable with Brizendine's frequent references to the antidepressant Zoloft. Peterzell felt that amounted to not so subtle product placement throughout the book. Peterzell also disagrees with Brizendine about the extent that inherent inborn brain differences affect men and women. Furthermore, Peterzell argues that Brizendine either understated or ignored entirely the significant influences of environment and socialization on brain development, as opposed to differences at birth.

Professor Mark Liberman in the Boston Globe, Fact-checking the Female Brain, shows how Brizendine pulled one of her statistics from self-help guru Allan Pease who appears to have provided it without evidence.