Disentangling the effect of sex from brain size on brain organization and cognitive functioning.

ABSTRACT: Neuroanatomical sex differences estimated in neuroimaging studies are confounded by total intracranial volume (TIV) as a major biological factor. Employing a matching approach widely used for causal modeling, we disentangled the effect of TIV from sex to study sex-differentiated brain aging trajectories, their relation to functional networks and cytoarchitectonic classes, brain allometry, and cognition. Using data from the UK Biobank, we created subsamples that removed, maintained, or exaggerated the TIV differences in the original sample. We compared regional and vertex-level sex estimates across subsamples. The overall sex-related differences diminished in head size-matched subsamples, suggesting that most of the observed variability results from TIV differences. Furthermore, bidirection

SUBMITTER: Brzezinski-Rittner A 

PROVIDER: S-EPMC11872830 | biostudies-literature | 2025 Feb

REPOSITORIES: biostudies-literature