Neurosexism

Neuroscientist Gina Rippon defines neurosexism as follows: Neurosexism' is the practice of claiming that there are fixed differences between female and male brains, which can explain women's inferiority or unsuitability for certain roles." Many of the issues they discuss to support their position are "serious issues for all areas of behavioral research", but they argue that "in sex/gender differences research... they are often particularly acute." The topic of neurosexism is thus closely tied to wider debates about scientific methodology, especially in the behavioral sciences. ==History==

The history of science contains many examples of scientists and philosophers drawing conclusions about the mental inferiority of women, or their lack of aptitude for certain tasks, on the basis of alleged anatomical differences between male and female brains. Absent a sexist background assumption about male superiority, there would be nothing to explain here. Despite these historical pseudo-scientific studies, Becker et al. argue that "for decades" the scientific community has abstained from studying sex-differences. Larry Cahill asserts that today there is a widely held belief in the scientific community that sex-differences do not matter to large parts of biology and neuroscience, apart from explaining reproduction and the workings of reproduction hormones. Although overtly sexist statements may no longer have a place within the scientific community, Cordelia Fine, Gina Rippon and Daphna Joel contend that similar patterns of reasoning still exist. They claim that many researchers who make claims about gendered brain differences fail to provide sufficient warrant for their position. Philosophers of science who believe in a value-free normative standard for science find the practice of neurosexism particularly problematic. They hold that science should be free from values and biases, and argue that only epistemic values have a legitimate role to play in scientific inquiry. However, contrary to the value-free ideal view, Heather Douglas argues that 'value-free science is inadequate science' == Examples in science ==

Prenatal hormone theory Contemporary research continues in a more subtle vein through Prenatal Hormone Theory. According to the Prenatal Hormone Theory, "male and female foetuses differ in testosterone concentrations beginning as early as week 8 of gestation [and] the early hormone difference exerts permanent influences on brain development and behaviour." Charges of neurosexism may then be moved against the PHT if these alleged hormonal differences are interpreted as causing the male/female brain distinction and in turn are used to reinforce stereotypical behaviours and gender roles. These two characteristics can be seen amongst young girls and boys. Girls have a tendency to play with baby dolls when they are young, enacting their social and emotional skills. Boys tend to play with plastic cars, illustrating a more mechanical, system-driven mind. This may be of course due simply to the environment and to social norms. However, the empathising-systematising theory posits three broad brain types, or organisation structures: type E, the empathiser; type S, the systematiser; type B, the 'balanced brain'. Given that females are twice as likely to display brain type E, and males are twice as likely to display brain type S, he labels these brain 'types' the 'female brain' and the 'male brain', respectively. This type of analysis suggests therefore that most (or at least some) differences in skills and occupation between males and females can be explained by virtue of them having different brain structures. Baron Cohen's theory has been criticised because it presents a clear-cut dichotomy between male and female brains, whilst this is not necessarily the case: there are females with 'male brains', and males with 'female brains'. Using the gendered labels makes it significantly more likely that evidence of gendered brain differences will be over-stated in the media, in way that might actively shape the gender norms within society. Neuroimaging In Delusions of Gender, Cordelia Fine criticises work by Ruben and Raquel Gur and collaborators. she quotes them as claiming that "the greater facility of women with interhemispheric communications may attract them to disciplines that require integration rather than detailed scrutiny of narrowly characterized processes." This contention is however corroborated by a 2014 study about the structural connectome. The study used 949 youths to establish novel sex differences, establishing the key difference that male brains are optimised for intrahemispheric communication, while female brains are optimised for interhemispheric communication. Furthermore, the development timeframe of male and female brain are vastly different. However, this study used youths from age 8 to 22, where the brain is still developing so the results may not be conclusive enough. In a 1999 study, Gur et al. found a link between the amount of white matter in a person's brain and their performance on spatial tasks. Fine points out that the sample size of ten people is a small sample size, and the researchers tested for thirty-six different relationships in this sample. This study was taken to support sex differences in emotional processing by Allan and Barbara Pease in their book ''Why Men Don't Listen and Women Can't Read Maps and by Susan Pinker in her book The Sexual Paradox''. Fine argues that, with a sample size of just 16, the results could easily have been false positives. She compares the study to a famous 2009 study in which, to illustrate the risk of false positives in neuroimaging research, researchers showed increased brain activity in a dead salmon during a perspective-taking task. Dispute between Fine and Baron-Cohen A notable dispute in 2010 between Fine and neuroscientist Simon Baron-Cohen in The Psychologist magazine centred on a study into sex differences in the responses of newborn babies to human faces and mechanical mobiles. Baron-Cohen replied to the fatigue argument by explaining that the stimuli were shown in randomised order, so as to avoid the problem of specific stimuli fatigue in either sex. In response to the claim about bias, he argued that the judges were only able to assess the babies' eye movements by watching a video of the eye area of the baby, through which it would have been almost impossible to derive the sex of the baby. Notwithstanding this, Fine argued that the effort to conceal the babies' sex from the experimenters in the room with the babies was "minimal", allowing room for implicit bias, rendering the results unreliable. Congenital adrenal hyperplasia Rebecca Jordan-Young provides a good case study of neurosexism in studies of those with congenital adrenal hyperplasia (CAH). Because Prenatal Hormone Theory posits early steroid hormones during fetal development as conducive to sex-typical behaviours, studies of genetic females with CAH are important to test the feasibility of this hypothesis. Jordan-Young conducts a comprehensive review of these studies, finding them to neglect four broad categories of variables that plausibly affect psychosexual development: "(1) physiological effects of CAH, including complex disruption of steroid hormones from early development onwards; (2) intensive medical intervention and surveillance, which many women with CAH describe as traumatic; (3) direct effects of genital morphology on sexuality; and (4) expectations of masculinisation that likely affect both the development and evaluation of gender and sexuality in CAH." Complex and continuous interactions between biological factors, medical intervention, and social pressures suggest a more holistic explanation for atypicalities in the psychological make up and behaviour of those with CAH than the conventional explanation that prenatal hormones "masculinise" the brain. Neglecting these four categories in our methodology of studies into those with CAH then favours the sex difference hypothesis, providing a clear example of neurosexism in scientific research. However, studies of CAH fail to account for unusual childhood experiences, parental expectations or reporting bias. == Examples in scientific communication ==

The media reporting of the neuroscience of sex differences has also attracted criticism. A high-profile example was the reporting of a 2014 neuroimaging study on sex differences the structural connectome of the human brain. The study used diffusion tensor imaging to investigate white matter connections in the brains of 949 participants ranging from 8 to 22 years old. The authors claimed to have discovered "fundamental sex differences in the structural architecture of the human brain". The analysis showed that information from the scientific article was given "increasingly diversified, personalized, and politicized meaning" in media outlets and was widely seen to have vindicated traditional gender stereotypes, even though the neuroimaging technique used could only detect structural differences, not functional differences, between the sexes. == Methodological issues ==

According to Cordelia Fine and Gina Rippon, there are systematic methodological issues in the neuroscience of sex differences that increase the chances of neurosexism. has criticised the small sample sizes that are typical of Functional Neuroimaging (FNI) studies reporting sex differences in the brain. She supports this claim with a meta-analysis. She takes a sample of thirty-nine studies from Medline, Web of Science, and PsycINFO databases, published between 2009 and 2010, in which sex differences were referred to in the article title. Fine reports that over the entire sample, the mean number of males was 19, and the mean number of females was 18.5. Disregarding the studies making sex-by-age and sex-by-group comparisons (which require larger sample sizes), the average sample sizes were even smaller, with a mean of 13.5 males, and a mean of 13.8 females. She also points out that the second largest study in the group reported a null finding. Small sample sizes are problematic because they increase the risk of False positives. Not only do false positives misinform, but they also "tend to persist because failures to replicate are inconclusive and unappealing both to attempt by researchers and to publish by journals". == Criticism ==

Simon Baron-Cohen has defended the neuroscience of sex differences against the charge of neurosexism. In a review of Delusions of Gender, he said that "Ultimately, for me, the biggest weakness of Fine's neurosexism allegation is the mistaken blurring of science with politics", saying that "You can be a scientist interested in the nature of sex differences while being a clear supporter of equal opportunities and a firm opponent of all forms of discrimination in society." == See also ==