Why Girls will be Girls…

Critique of “Why Girls Will Be Girls”, published in Newsweek, July 2006.


The article, Why Girls Will Be Girls, featured in popular magazine, Newsweek, reported on Louann Brizendine’s first book, The Female Brain. It attempted to describe some of the main arguments put forward in Brizendine’s book, which essentially advocates the seemingly politically incorrect view that differences in gender are biologically determined through differences in the brain and hormones. Brizendine is reported to suggest that there are biological reasons why girls are predisposed to certain behaviours and boys others, for instance why girls tend to play with dolls and boys enjoy more rough and tumble play. The article explains Brizendine’s position in some of the basic scientific terms put forward by Brizendine in her book. In brief they are as follows: women have 11% more neurons in the area of the brain devoted to memory and emotions and they have higher levels of estrogens, cortisol and dopamine. These biological differences, for Brizendine, are reported to be factors in explaining why females behave in certain ways, for example, why they tend towards higher levels of stress in situations of emotional conflict. The Female Brain is also reported to state that because women have more mirror neurons, women are better at observing emotions in others. However, Brizendine’s ideas are controversial and the article also mentions two major critics of Brizendine’s work: Janet Hyde and Dr. Nancy C. Andreasen. Hyde’s position, as reported in the article, is that the results of her meta-analysis show that gender differences are minimal. Andreasen argues that nurture cannot be underestimated in the study of gender differences and biological explanations are used to oppress women. However, Brizendine argues that differences should not be understood as equal to inferiority.


To evaluate the article and the views contained within it, this essay will need to examine the key issues advocated by Brizendine and the opposition to them. The main points to be considered are the role of sex hormones in gender and gender differences in brain. In addition to the main biological issues, it is also necessary to investigate their relationship to the environment and examine gender theories emphasising nurture over nature. Evidence suggesting a greater role for nurture than nature, whilst would not refute that there were biological factors in determining gender differences could suggest that Brizendine’s emphasis on biological differences was misplaced or wrongly biased. Evidence to suggest the importance of biology over environment would, on the other hand, support some of the claims made in the article. A combination view would need to investigate the contributions of various factors and investigate how they fit with the assertions contained in the article.


On Brizendine’s claim that the differences in levels of sex hormones in females and males in determine gender behaviour, it is necessary to examine their role in the development of the sexes. The sex of a human is determined by the 23rd pair of chromosomes; in females the pair is made up of XX and in males it is made up of XY. The Y is held to be the gene that causes the male gonads to develop into testes, which occurs at 6 weeks. Later, at 12 weeks, in female embryos they develop as ovaries. Both male and females have both “male hormones” known as androgens and “female hormones” known as estrogens but the Y in the male causes the testes to develop, which causes a predominance of androgens, the hormone commonly linked with male behaviours. However, it is important to note that so-called female hormones (both estrogens and some synthetic forms of progesterone) can have a masculinising effect on behaviour also although a dominant presence of female hormones does coincide with feminine behaviours (Golombok and Eivush 1994).


The importance of the sex hormones can be further established by supporting evidence from studies that show their effect on gender identity regardless of genetic sex. Genetic girls exposed to high levels of androgenic hormones before birth exhibited more male behaviours, such as rough and tumble play in childhood and were known as “tomboys” (Money and Erdhardt, 1972). In addition, studies found that increased levels of female hormones had effects on the male foetus, lessening masculine behaviours and heterosexual experience in the boys in later life (Baker, 1980). A particularly interesting example of the role of prenatal sex hormones is that of a patient of Money’s, commonly referred to as ‘the boy reared as a girl’ (Berk, 2000). Losing his penis in a circumcision accident at 7 months old, the parents worked with Money to reassign his gender surgically and by giving him female hormones. Although she looked like a girl in as far as genitals and secondary sex characteristics, her physical size, behaviours and desires were masculine despite hormone therapy. At fourteen, when told of her medical history, the patient requested to be reassigned back to a male gender and lived as a man once again until his suicide (Berk 2006). This case has been used as very strong evidence that sex hormones before birth play a large role in determining the gender-behaviours developed, regardless of development post-birth.


However, there has been opposition to these explanations. One is that girls who experienced higher levels androgens before birth were born to parents who were aware that they had been “masculinised” before birth and due to that belief treated them as they would boys, therefore altering their development socially (Archer and Lloyd 1982). With reference to the case of the boy reared as a girl, it has been suggested that the gender identity confusion could have been caused by her masculine size (tall, broad shoulders) and her perception of what that meant in the context of her society rather than due to prenatal hormones (Golombok and Eivush, 1994). It has been argued that gender identity stems more from such social experiences and that at an early age children begin to develop gender schemas (categories of gender behaviours), which they learn from experience and then apply to their own behaviours (Berk, 2006). One study demonstrated the strength of gender schemas when an adult labelled some toys as boys’ toys, some as girls and other unlabelled. The children showed a high tendency to desire the toys intended for their gender and ignore the toys intended for the other gender (Martin, Eisenbud, and Rose, 1995) demonstrating the importance of socially developed gender identity and behaviour.


Contrary to the view that minimises the role of sex hormones before birth, studies of people with conditions that alter their usual exposure to sex hormones support their importance in gender identity. For example, males with Complete Androgen Insensitivity are insensitive to androgen, which means that despite the Y chromosome they develop genitals that are female in appearance. Although they do not menstruate and are infertile, they are usually raised as girls (as the condition is not spotted until puberty) and develop a female gender identity.  Girls born with Congenital Adrenal Hyperplasia, which produces high level of androgens from the prenatal period onwards, when assigned and raised as male, adopt a male identity (Golombok and Eivush, 1994). These examples seem to suggest that the sex hormones are so important in gender behaviours that they over-ride the genetic sex of a person. Given these examples, it could be argued that Brizendine’s assertion that the differences in the hormones dominating the two genders are crucial factors in explaining gender differences can be substantiated.


However, studies on genetic abnormalities support a more nurture based explanation of gender identity. In Turner’s syndrome, a person has only one X and is not exposed to any sex hormones except maternal hormones. Although without a reproductive system, their external genitalia are female and they are raised as females and adopt a female gender identity. Whilst the studies of people with Congenital Adrenal Hyperplasia and Complete Androgen Insensitivity show the importance of sex hormones, Turner’s syndrome demonstrates that despite an absence of sex hormones gender identity develops, emphasising the role of society over that of biology. On the other hand, whilst Turner’s shows that an absence of sex hormones can be overcome, other conditions suggest that despite the ability of society to carve a gender identity without the usual biological background, the hormones do indeed influence gender behaviour, even if they are not acting alone, and can be supplemented or changed by the external environment. An example of this is Klinefelter’s syndrome, which causes males to have a male body but underdeveloped genitals and secondary sex characteristics and be infertile. These males do have a male gender identity in most cases, despite the atypical chromosomal and hormonal patterns, although they exhibit a reduction in typical masculine behaviours. In this case, it is possible to see both the external environment working to create a gender identity but the lack of male sex hormones causing a reduction in the strength of the identity.


As well as their direct effect, the sex hormones have prenatal influence on the development of the brain, in particular the hypothalamus. Brizendine’s book, as described in the article, suggests that there are significant differences in the brains of males and females, which are major factors in determining gender behaviour. There are differences in male and female brains, but how far these differences effect gender identity and how far they can be influenced by external factors needs to discussed. The hypothalamus is the control centre for the endocrine system in general and the sex hormones in particular. The sensitivity of the hypothalamus to stimuli (and hence its reaction to stimuli) is determined by the sex hormones it receives and produces and this state of affairs plays a crucial in the development of reproductive behaviours. It has been suggested that post-birth this cyclical relationship continues with environmental influences also playing a role (Anselmi and Law, 1998). According to Anselmi and Law (1998), external environmental factors can increase or decrease secretions of hormones, which in turn can inhibit or increase receptor site sensitivities in the hypothalamus, which will increase or decrease the sensitivity of the hypothalamus to environmental stimuli, which means that essentially the environment can have a direct influence on the biological factors that contribute to gender-related behaviour. Anselmi and Law (1998) therefore seem to suggest that whilst sex hormones and the structure of the brain are important factors in determining gender-related behavior, they can be changed and influenced by the external environment.


There have been other studies of the brain in relation to gender that have found differences that support Brizendine’s assertions that the female brain is different to the male brain and that these differences cause different gender behaviours. One common gender stereotype is that women are better communicators than men and this idea is supported by the biological fact that the development of the left hemisphere of the cerebral cortex (where language is localised) develops earlier in girls than boys (Berk, 2006). In addition, it has been shown that adult females have proportionally larger Wernicke and Broca language-associated regions compared with males (Harasty, Double, Halliday, Kril, McRitchie, 1997).


Further differences in brain structure have also been identified that could suggest an influential role for the brain in gender behaviours. It has been shown that there are both general and regional differences in brain measures in males and females and although the functional importance of this is unclear it is thought to represent the effects of gonad hormones during brain development (Andresen, Flam, O’Leary, 1999). However, differences in measure do not necessarily suggest differences in type. For instance, male and female patients with schizophrenia have the same pattern of structural brain abnormalities, but male patients appear to manifest greater severity (Andresen, Flam, O’Leary, and Noodles, 1997). If the differences in brain structure are tied to the sex hormones, clearly important factors in the development of gender behavior, perhaps this would mean that these sex-based structures also influenced gender behavior. Research into differences in the brain between heterosexuals and homosexuals has found that within the hypothalamus there were differences. Homosexual men and women had the same size INAH 3 (one of the small groups of neurons found in the hypothalamus), which was two to three times smaller than that of heterosexual men (Levy 1993). This supports that claim that differences in the brain have an effect on differences in gender behaviour if one accepts that homosexual men have a different gender identity than heterosexual men, which is arguable, even if one only suggests that sexuality is just one element of gender identity.


In conclusion, this essay has examined Brizendine’s claims that the sex hormones and the structure of the brain serve as the basis of gender identity. It has also outlined some of the main points of the opposing view, which emphasise the role society and development play in acquiring gender behaviours. There is supporting evidence to suggest that Brizendine is correct to assert that differences in sex hormones contribute to differences in gender behaviour. The examples of people with abnormal exposure to sex hormones in the cases of Complete Androgen Insensitivity and Congenital Adrenal Hyperplasia demonstrate the effect the hormones can have, regardless of biological sex. However, other cases such as Turner’s Syndrome, have also showed that even without sex hormones, gender identity develop normally, evidence that leads to the conclusion that social factors in gender development must also have a part to play. This essay has also described sex differences in the structure of the brain and suggested that the relationship of these differences to the sex hormones could be used as evidence that it too has a role in the development of gender behaviours. Perhaps the best way to view the interaction of the sex hormones, the subsequent or, at least, simultaneous differences in the brain, and the role of society is within the cyclical relationship described by Anselmi and Law (1998), which illustrated that whilst there are clear biological differences relating to differences in gender behaviour, they are influenced by the external environment as well as influencing it.


Although Brizendine’s critics argue that there are more similarities than differences and that to suggest a biological basis for gender differences will lead only to oppression of women, the evidence supporting her assertions cannot be ignored. However, one can accept that hormones and brain structure contribute to gender differences without accepting that these are always related to genetic sex differences. That there are more similarities than differences does not mean that the differences are not important. In addition, much of the evidence supporting the important role of sex hormones does so at the expense of the importance of genetic sex. Therefore, it is arguable that sex hormones and brain structure are important factors in gender identity but their development and manifestation is the result of a more complex structure. That is to say, Brizendine would be wrong to suggest that all biological women will act one way and all biological men another. Rather, males and females will develop gender identities based on the role of prenatal sex hormones regardless of genetic sex in some cases, the effect of these hormones on the development of the brain, the effect of the external environment on the production levels of sex hormones after birth, and the social context in which the individual is reared. Furthermore, given this argument, genetic males may exhibit behaviours usually linked to females and females may exhibit behaviours usually linked to males. Brizendine would therefore be correct to propose that gender behaviours are linked to sex hormones and brain structure, but would be wrong to infer that these would also necessarily relate to genetic sex. That is to say, gender behaviours may have their basis in biology, but that they can be influenced by society and are not simply related to their corresponding sex categories of “men” and “women”.  




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