Humans love putting labels on things. Especially other humans. One of the biggest debates across history is what defines the sexes. What is a woman? What is a man? What about those who aren’t quite either? And are they all really that different? As we have learned more about hormones, brain development, and genes, the conversation has only become more complicated.
Many social scientists have proposed the idea that gender is mostly, if not entirely, socially constructed. The neuropsychologist Gina Rippon (1) appears to neglect decades of scientific data to support such a view. In her recent book, “Gender and Our Brains: How New Neuroscience Explodes the Myths of the Male and Female Minds”, she suggests that much of scientific data on gender differences is misguided because girls and boys are treated differently since birth, and so environment is what causes apparent gender differences in brain and behavior. Brains are highly plastic (able to change), especially in early development, which Rippon asserts is the reason that they can so easily be molded to fit a society’s expectations for gender. She cites an example in which children view a video of someone being hurt while receiving an fMRI, which allows researchers to see which parts of the brain are active, and by how much. The children were asked how badly they felt watching the videos, as a measure of empathy. The girls tended to report more empathy as they aged, and the boys, less. However, their brain scans revealed the same amount of activity in the areas associated with empathy, regardless of age or sex. This implies that the children are filtering what they say they feel in order to conform to ideals of feminine and masculine behavior.
The flaw in Rippon’s argument is that she has blurred the distinction between gender roles, and aspects of gender identity and sexually differentiated brain physiology that are not expressed as behavior at all. By pushing the idea that biologist see sex as binary rather than along a continuum, she creates a false narrative that scientists are only looking for discrete differences between sexes, instead of trends. However, there is a wealth of data showing that our physiology, including our brain and sensory functions, are influenced by genes and hormones to create a continuum of responses in individuals that identify as male and female that are beyond the reach of cultural norms. All of these processes contribute to the expression of gendered behavior, which is culturally constructed, and gender identity, which has both biological and societal influences. Gender identity is how one perceives oneself and feels appropriately identified by the cultural labels of woman, man, or other. It may or may not translate into acting feminine, masculine, or androgynously.
To provide just one example that gender identity has a biological brain component, researchers (2) examined all the coding DNA sequences, the DNA that codes for proteins, in a sample of 30 transgender individuals. Genes associated with hormone pathways that determine whether a brain is likely to be typically feminine or masculine were different in these individuals, but not in the general population. This means differences in hormone function during development may be why some people feel like women, some like men, and some like something else.
The mysteries of human nature may never be fully explained, but accepting the idea that biology and culture both contribute to who we are can keep bringing us a little closer.
- Do men and Women have different brains? The New York Times (https://www.nytimes.com/2019/09/09/books/review/gender-and-our-brains-gina-rippon.html). Original book: Rippon, G. (2020). Gender and our brains: How new neuroscience explodes the myths of the male and female minds. Vintage.
- Medical College of Georgia at Augusta University. (2020, February 5). Gene variants provide insight into brain, body incongruence in transgender. ScienceDaily (www.sciencedaily.com/releases/2020/02/200205084203.htm). Original article: J. Graham Theisen, Viji Sundaram, Mary S. Filchak, Lynn P. Chorich, Megan E. Sullivan, James Knight, Hyung-Goo Kim & Lawrence C. Layman (2019) Gene variants provide insight into brain, body incongruence in transgender. Scientific Reports 9, 20009
Department of Biology
University of Mississippi