The Transgender Experience

Is There a Female Brain?

Rebecca Juely
Jan 25 · 6 min read
Image for post
Image for post
picture courtesy of canva.com

Heresy, politics, prejudice, and junk science plague discussion on trans identities. In search of some real science, I stumbled upon this 2021 academic paper. It was a challenging read, but here goes my summary of one part of this 23,000+ word paper. See what you make of it.

Biology has been instrumental in many narratives on the sexes, including those that justify gender inequalities based on supposed differences in women’s organs, hormones and brains. In contrast, Feminist ‘degendering’ theories destabilise the fixed and biological roots of sexual differences. Feminist degendering wishes to challenge simplistic divisions of nature/culture and sex/gender and to eradicate gender difference. Feminists wish to explain away difference solely on the basis of cultural conditioning. However, the call to free ourselves from the categories of gender presents a problem.

The origins of sex differences in the brain (both structural and functional) are more attributed to the combined effects of hormones, genes, epigenetics, as well as the social environment There is a narrative in all societies that ascribes emotion to women and violence to men. At the risk of placing certain human behaviors into pigeonholes, can we derive gendered cognitive differences from the surplus of previous studies related to the differences in the reproduction burden? We may find one clue within the knowledge that human neonates are dependent on others for their survival for a very long time.

Specific innate behavioral differences in the brain are presented here as limited to factors surrounding reproduction. Gonads determine body sex — the XX ovum, XY spermatozoa, and later evidenced by physical and reproductive anatomy. Outside the XX ovum and XY spermatozoa, mammalian bodily sex is differentiated during pregnancy, i.e., before birth, yet, bodily sex is not strictly dimorphic. While it may be recognized XX / XY genetic binaries direct different classification of organisms, the existence of intersex bodies, although rare, testifies to some overlapping of bodily sex along a canalized[i] (guided) spectrum.

Image for post
Image for post

At the XX endpoint of the sex spectrum, there are those whose bodies are especially ‘pink’ (feminine). These are at the extreme feminine end of the spectrum; a circular skull, wide eyes, small nose, small jawbone, narrow shoulders and waist, wide pelvic floor; light musculature; temple hair, smaller hands, third finger shorter than the first, and smaller feet. At the extreme XY endpoint, there are those whose bodies are mostly ‘blue’ (masculine); an oval skull, narrower eyes, larger nose, larger jawbone, broader shoulders, narrower pelvic floor, heavy musculature, little to no temple hair, larger hands; third finger longer than the first; and larger feet. In-between, there is an infinite variety of everyone else. There are an estimated 450 quadrillion possibilities of dimorphism.

When the Y chromosome is absent in the human embryo, its bipotential primordial genital structures develop into female internal and external reproductive organs. This development does not account for gender incongruence after childbirth. The dominance of testosterone from around birth results in masculinization of the fetus. Essentially, in an XY genetic template, testosterone de-feminizes and masculinizes the fetal reproductive axis (RA) at around nine weeks (the reproduction axis stems from the testes, ovaries, and on to neural systems). In the developing male, testosterone is produced by the fetal testes under an SRY gene’s influence on the Y chromosome. An XY genetic template results in the formation of a male RA, including the gonads. Under an XX genetic template, and without the influence of any SRY gene on either X chromosome, relatively little testosterone is produced. The adrenal glands secrete the enzyme aromatase (also called estrogen synthase) that converts androgens to estrogens, which feminize the RA, including the gonads. At the end of the seventh gestational week the gonads are developed and bodily sex is determined, while other parts of the reproductive system, including the brain [gender], are still bipotential. Notably, immediately before and after birth, testosterone levels organize fetal male and female brains differently. Thus, the fetus is anatomically organized, differentiated, and producing sex hormones before neurogenesis (development of nerve cells including the brain) is complete.

In this way and notwithstanding other influences, an XY fetus mostly produces a male inclined brain (gender) with latent adolescent sexuality. An XX fetus mainly grows a female predisposed brain (gender) with latent adolescent sexuality. Adolescence itself is a time of gender intensification. Thus, gender is conventionally an innate trait related to reproduction. However, this sequential displacement of body and brain development means it is possible for the sex of the genitalia, brain gender identity, and sexual orientation to become discordant.

The Female Brain.

The reproductive axis (RA) likely accounts for the expression of specific behaviors relevant to the rearing of offspring. Our theory is that parental cognitions are biologically relevant to reproduction that follows the RA’s differential development.

Estrogen sensitivity within areas of the brain defines mammalian maternal behavior via multiple neural and endocrine systems across the lifespan. Advanced functional magnetic resonance imaging studies reveal how the female human brain responds to infant-related cues. The differences responsible for actions relevant to reproduction are lifelong and set in utero.

The emotional behaviors most associated with mothering are cues of trustworthiness and empathy. In contrast, the remainder of the actions are a mosaic available to both sexes. Women tend toward better social and linguistic skills. In contrast, men tend toward higher physical abilities combined with technical, spatial, and navigating — behaviors which are also relevant to reproduction.

We may find clues within the knowledge that human neonates are dependent on others for their survival for a very long time. Human babies have an extended juvenile period, and young offspring’s care requires teamwork from parents, yet such care exhibits striking sex differences. The teamwork subsumes attachment, suckling, emotional nurturance, and parental sensitivity to danger. Caregiving by most animals, including humans, is teamwork yet highly sexually dimorphic. Fathers support maternal care; for example, across all mammalian species, aggression is a fundamental means to defend territory, compete for mates and food, and protect offspring.In sum

Human development in the womb is arguably a period when the fundamentals of gender as specific cognitions are laid down after the establishment of the embryo’s sex. For species survival, specific cognitions are tethered to reproduction and care of offspring. Reproduction of our species demands differentiation in the physical and psychobiological care of offspring. After heterosexuality, the two most notable differences in cognitive behaviors discussed here occur concerning offspring’s care are empathy and aggression.

Post adolescence, sexually dimorphic courtship is tethered to sexually dimorphic mating behavior, which is tethered to sexually dimorphic Mothering and Fathering, which is, in turn, tethered to dimorphic roles in the care of offspring. The differential networks are presented here, are reflected in the specific behaviors relevant to reproduction stemming from the RA. Females’ higher levels of empathy are likely the why women mother, whereas fathers predominate in other parental areas. Women in advanced societies can earn their keep via many career paths, yet they generally tend to earn it as a housewife. Men generally earn their keep in work outside the home.

Criticisms that science has historically separately pigeonholed many male and female behaviors is justified. What’s more, biology has [often] been used to subjugate and suppress the rights and experiences of women and other marginalised groups. Nevertheless, a biologically narrative is appropriate given certain behaviors are necessary for reproduction of the species.

Adapted from Sex vs. Gender: A Biological Location for Gender, not sex. Used with permission.

[i] Most species maintain abundant genetic variation and experience a range of environmental conditions. While observable characteristics of mammillian sexual variation are low, they do exist. Canalized refers to that which is moderately focused on male and female endpoints to enhance sex differences.

Sign up for Empowered Trans Woman Updates

By Empowered Trans Woman

Keeping you in the loop. Take a look.

By signing up, you will create a Medium account if you don’t already have one. Review our Privacy Policy for more information about our privacy practices.

Check your inbox
Medium sent you an email at to complete your subscription.

Rebecca Juely

Written by

Interests in issues of sex, gender, and psychological androgyny.

Empowered Trans Woman

Highlighting the experience of women of trans experience. Transition, Womanhood, Feminism, Intersectionality, Transphobia, Marginalization and Assimilation, and more.

Rebecca Juely

Written by

Interests in issues of sex, gender, and psychological androgyny.

Empowered Trans Woman

Highlighting the experience of women of trans experience. Transition, Womanhood, Feminism, Intersectionality, Transphobia, Marginalization and Assimilation, and more.

Medium is an open platform where 170 million readers come to find insightful and dynamic thinking. Here, expert and undiscovered voices alike dive into the heart of any topic and bring new ideas to the surface. Learn more

Follow the writers, publications, and topics that matter to you, and you’ll see them on your homepage and in your inbox. Explore

If you have a story to tell, knowledge to share, or a perspective to offer — welcome home. It’s easy and free to post your thinking on any topic. Write on Medium

Get the Medium app

A button that says 'Download on the App Store', and if clicked it will lead you to the iOS App store
A button that says 'Get it on, Google Play', and if clicked it will lead you to the Google Play store