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The Female Brain

Caroline H's picture

In her book, The Female Brain, Louanne Brizendine describes the stages that the female brain goes through during life, citing brain structure and chemistry as the departure for differences between the male and female brains. Most of the misunderstanding of female psychology, Brizendine notes, stems from the misconception held by scientists during most of the 19th and 20th centuries - “that women are essentially small men in psychology and physiology”. She says that it is important to make the distinction between male and female psychologies because physiological sources for these differences do exist, contrary to the reality that they are usually just brushed off as mere deviations during studies. However, it is from this weakness of the methodologies that Brizendine builds her case: that the female brain differs from the male brain because of the predominating role that neurohormones, or hormones that behave as neurotransmitters, play in development and function of the brain.

The influence of neurohormones with regard to differences between males and females include areas and circuits of the brain that are engaged when given a certain task, size of structures, and while also “[determining] what the brain is interested in doing”. These hormonal differences also partially account for the fact that “the female and male brains process stimuli, hear, see, 'sense,' and gauge what others are feeling in different ways”. The idea that structure determines function is also closely interrelated with the role of neurohormones. For example, the hippocampus, which is implicated in the function of memory and emotion, is typically larger in the female brain than it is in the male brain. On the other hand, the amygdala, the center of the brain relating to instinctive aggression, is usually larger in the male brain. Some neurohormones that affect the female brain speficically and spike several times in a female's life are estrogen, progesterone, and oxytocin. Brizendine delineates the female life by the major hormonal changes which, with female-specific changes in the brain, amount to a kind of “reality change”, as Brizendine calls it.

All brains start out female, and it is only at the eighth week after conception that male brains begin to differentiate. After birth, surges of female hormones like estrogen begin to flow during the ages of 6-24 months. The estrogen serves to build up emotional and verbal circuits in the baby girl's brain, making her quite adept at picking up facial and vocal cues right from the start. She is especially responsive to her mother's actions, usually following suit of her behavior and emotions. Overall, this period of time helps to prepare the circuits that deal with intuition, empathy, communication, and relationships.

The next spike in hormone synthesis and distribution comes during puberty. Estrogen, progesterone, and testosterone cycle regularly, and in a way, make puberty an extension of the circuit priming that happened during girlhood. The areas for communication, emotion, and most of all, stress, are built on during this time. Brizendine emphasizes that the ups and downs of teenage life are especially characteristic of the female experience – she describes the girl's brain as “sprouting, reorganizing, and pruning neuronal circuits that drive the way she thinks, feels, and acts – and obsesses over her looks” (31). These are caused by daily changes in estrogen and progesterone, which cause the temperamental nature and mood swings the girl experiences. Brizendine also attributes the social conditions that the teenage girl usually encounters (e.g. aggression, cliques, bullying) to these regular changes.

The stages that follow are quite different than the tumultuous struggle that is female adolescence – young adulthood is characterized by independence, sexual maturity, and love. The woman becomes focused on her career and relationship development, seeking to strike a balance between the two. During this period of time, oxytocin rises to the forefront along with estrogen, interacting most during the search for a lifelong mate. The neurohormones help cultivate love and trust as well as pair bonding and attachment. Brizendine pinpoints each of the stages' characteristics to specific sets of hormones and circuits in the brain that are activated. Most of the cycle of the woman's early adult life that she describes centers primarily around relationships, having children, and child rearing. Although biologically and culturally, many women do enter this cycle, I am interested to see what physiological changes would occur during this time for women who do not get married or have children. How would the biological instincts for maternity play out in a life where they are not used to their full extent and what kind of physiological effects would this entail? Perhaps the woman would simply continue to pursue her own personal interests and career, and circuits for executive function would be developed. It would be certainly different for all women, but it would be interesting to see if any trends in physiology did exist.

Brizendine cites the menopausal stages as the most important factor in the shaping of the mature female brain. The last hormone-induced change comes during menopause, when low levels of estrogen tend to dominate, and previously active cycles, like those that deal with estrogen, oxytocin, and progesterone, begin to dwindle. The lessening hormone levels become the reason for the increasing calmness that the mature woman experiences. Her focus shifts over to pursuing her own interests and away from actively caring for others as she did during child rearing. She concludes that because menopause and the time periods after it are still relatively “new” (life expectancies in previous centuries were not nearly as high), there is still much more to explore in the mature female brain.

While psychology textbooks might tell us what happens in the brain during development and disorders, Brizendine's account of the female brain can explain the force behind some of the discrepancies between male and female psychology. She also explains that her intention for writing the book was to create a sort of road map for women to delineate what exactly is going on during some of the most hectic and potentially confusing times of their lives. Unfortunately the exact neurohormones that develop and cultivate the female brain also serve to muddle things into an incomprehensible jumble of happenings and emotions. Brizendine's book certainly provides for an invaluable resource for all women who would like to explore in depth their minds and the physiology behind them.