Here is the frequency distribution of the (A) Youth Self-Report and (B) Parent-Report Gender Questionnaires from the Supplementary Materials.

One explanation is that males may face lower social tolerance for gender nonconformity, leading boys to feel pressured to answer gender-related questions less truthfully, resulting in high sex/gender alignment scores despite rsFC patterns less similar to the typical male profile.

In males, however, there was an unexpected negative correlation: Those with higher rsFC sex SVM scores showed lower sex/gender alignment.

In females, the extent to which their brain rsFC matched a female or male sex profile was positively associated with the degree of sex/gender alignment, with higher rsFC sex SVM scores corresponding to greater sex/gender alignment.

The rsFC sex classifier, trained solely on youth with sex/gender alignment, was significantly better at classifying individuals with sex/gender alignment than unalignment. This suggests that gender may have a greater influence on functional connectivity patterns than neuroanatomy.

Key brain networks involved in predicting sex include association networks (default mode, dorsal attention, and parietal memory) and visual networks (visual and medial visual).

We found that rsFC significantly outperforms cortical thickness and cortical volume in predicting sex. This suggests that even in a young cohort, resting neural activity patterns capture subtle, sex-specific functional dynamics that structural measures like cortical thickness/volume may not reveal.

We leveraged data from ~3,200 youth in the Adolescent Brain Cognitive Development Study (ABCD) in the USA and Support Vector Machine learning to predict both sex (assigned at birth) and sex/gender alignment (the congruence between sex and gender) from rsFC, cortical thickness, and cortical volume.

Although many neurological and psychiatric conditions vary by sex in prevalence, onset, and symptomatology, possibly due to differences in brain structure or function, evidence on brain differences related to sex and gender remains inconclusive.

Is resting-state functional connectivity (rsFC), cortical thickness (CT), or cortical volume more effective at capturing sex and gender differences in the brains of preadolescents?

Check out our new article (doi.org/10.1016/j.dc...) now out in Developmental Cognitive Neuroscience.

Happening now! Don’t miss out - Come find me at Poster Session E (#E127) at #CNS2025 to discuss how brain functional connectivity, but not neuroanatomy, captures the interrelationship between sex and gender in preadolescents.
@cnsmtg.bsky.social

At #CNS2025? Come visit my poster (#E127) Mon afternoon (2:30-4:30pm) to learn how brain functional connectivity, but not neuroanatomy, captures the interrelationship between sex and gender in preadolescents
@cnsmtg.bsky.social @ndosenbach.bsky.social

Preprint here: www.biorxiv.org/content/10.1...