Another Science family paper of interest on sex and gender

Sex and gender may be encoded differently in the brain

Yesterday, President Trump said in his inauguration speech that “as of today, it will henceforth be the official policy of the United States government that there are only two genders, male and female.” He then signed an executive order codifying many of these ideas. The word “biologically” appears many times in the order to support the idea that sex and gender are simple binaries, but the literature contains a great deal of research showing that gender is much more complicated, supporting the idea that sex and gender operate differently.

Last year, we published a paper in Science Advances called “Functional brain networks are associated with both sex and gender in children.” The paper uses brain imaging to produce evidence that sex and gender are controlled by two separate systems in the brain during development and that while a sex binary can be predicted from these data, a gender binary cannot.

The authors are: ELVISHA DHAMALA, DANI S. BASSETT, B.T. THOMAS YEO, AND AVRAM J. HOLMES.

Here is the abstract:

Sex and gender are associated with human behavior throughout the life span and across health and disease, but whether they are associated with similar or distinct neural phenotypes is unknown. Here, we demonstrate that, in children, sex and gender are uniquely reflected in the intrinsic functional connectivity of the brain. Somatomotor, visual, control, and limbic networks are preferentially associated with sex, while network correlates of gender are more distributed throughout the cortex. These results suggest that sex and gender are irreducible to one another not only in society but also in biology.

We also published an excellent Focus article that analyzes the paper and provides additional context: “How sex and gender shape functional brain networks.” Here is a very illustrative figure from that article:

The paper shows that brain network data can be used to predict sex in a binary fashion with a high degree of certainty. But for gender, predictions were no better than chance when properly controlled for sex. Further, the two systems of connections used were separate.

Read the papers and decide for yourself. Comments open, and if you see any problems with the paper, you can send a note to science_data@aaas.org, and we’ll take a look.