Researchers from the University of Pennsylvania and Feinstein Institutes for Medical Research have uncovered latest insights into how sex and gender are represented in children’s brains.
The study, published in , contributes to debates surrounding the connection between biological sex and gender identity and the way, and if, we are able to study this objectively.
Sex and gender, while sometimes used interchangeably, have come to separate sex in biological terms as assigned at birth from the more variable sociocultural notion of gender.
In the study’s words, “Here, we use the term “sex” to point features of a person’s physical anatomy, physiology, genetics, and/or hormones at birth, and we use the term “gender” to point features of a person’s attitude, feelings, and behaviors.”
To wrangle answers from the brain itself, the research team analyzed brain scans from 4,757 children aged 9 to 10 to look at how different parts of the brain communicate.
They then employed a series of predictive AI models to find out that while each sex and gender are related to distinct patterns of brain connectivity, these patterns usually are not similar.
Study approach and findings
The team used an enormous dataset from the Adolescent Brain Cognitive Development (ABCD) Study, which incorporates detailed brain scans and behavioral information from hundreds of kids across the United States.
The researchers used functional magnetic resonance imaging (fMRI) to watch natural patterns of brain activity while children were at rest within the scanner.
They then employed sophisticated machine learning algorithms (ridge regression models) to search for patterns on this brain activity that is perhaps related to sex or gender.
Sex was defined in accordance with the kid’s sex assigned at birth, which is Assigned as either Female at Birth (AFAB) or Male at Birth (AMAB).
For gender, the researchers used two separate measures:
- Self-reported gender: Children answered questions on their felt-gender, gender expression, and gender contentedness.
- Parent-reported gender: Parents answered questions on their child’s sex-typed behavior during play and any signs of gender dysphoria.
Importantly, gender was considered on a continuum, not as a binary. The researchers didn’t categorize children into specific gender groups, but somewhat used these scores to position children along a spectrum of gender expression and identity.
This provided two different perspectives on each child’s gender identity and expression.
Here are the important thing findings:
- Sex prediction: The researchers found they may discover whether a toddler was male or female with about 77% accuracy based on their brain connectivity patterns.
- Gender prediction: When it got here to predicting a toddler’s gender (based on the parent reports), the accuracy dropped dramatically – to only about 8%. This suggests that while gender does have some relationship to brain function, it’s way more subtle and sophisticated than differences attributed to sex alone.
- Different brain networks: The brain patterns related to sex were mainly present in areas involved in movement, vision, decision-making, and emotions. In contrast, the patterns related to gender were more opened up across the brain.
- Gender conformity: The study found that boys tended to indicate more gender-typical behavior than girls, in accordance with each the kids’s own reports and their parents’ reports. This aligns with social science research suggesting that boys often face more pressure to evolve to gender norms.
- Self-reported gender: Intriguingly, the researchers couldn’t reliably predict how children viewed their very own gender based on brain scans, highlighting the complexity of gender identity.
This research suggests that to completely understand the differences and similarities between men and women, and between children of various gender identities, we’d like to take a look at sex and gender.
They appear to influence brain development in distinct, though related, ways.
The study concludes, “Together, these findings suggest that the functional correlates of sex are distinct from the functional correlates of gender, and the unique multidimensional constructs that comprise gender are differentially related to functional connectivity patterns in AFAB and AMAB children. As such, sex and gender must each be studied concurrently to completely capture the differences and similarities that exist between men and women, between girls and boys, and between other genders.”
However, the researchers caution against misinterpretation. Their paper emphasizes that “these results don’t provide evidence for gender essentialism,” addressing concerns about reinforcing harmful stereotypes.
Both sex and gender are “essential components of identity,” but “It’s becoming an increasing number of clear that just sex itself shouldn’t be enough,” says Elvisha Dhamal from Feinstein Institutes for Medical Research and the Zucker Hillside Hospital and lead writer on the brand new study.
The study highlights how fluid and multifaceted gender identity may be, especially in young children.
In medicine, understanding how sex and gender individually influence brain function might result in more personalized treatments for neurological and psychiatric conditions. This could possibly be particularly helpful for disorders that manifest in another way across sexes or gender identities, similar to ADHD and autism.
It could also contribute to more nuanced mental health support for youngsters experiencing gender or identity-related challenges.
Perhaps most pertinently within the short term, by demonstrating that sex and gender have distinct neurological correlates, this study provides scientific evidence against oversimplified notions of “male brains” and “female brains.”
It builds on a similar recent Stanford study that accurately discerned male from female brains 90% of the time.
