Sex differences in structural and functional connectivity in healthy young adults from the Amsterdam Open MRI Collection.

Understanding the structural and functional differences in the brain between sexes may provide insight into the sex differences in behaviors, cognition, and disorders. Structural (SC) and functional (FC) connectivity were examined in this study on 111 (Females = 56) right-handed, healthy, young adults controlled for brain size, using the cluster and region-of-interest (ROI) based algorithms. A nearly moderate correlation between SC and FC was observed for both male and female cohorts, but the degree of correlation was not significantly different between the sexes. Sex differences in SC were found in both intra- and inter-hemispheric clusters and connections, with more differences in the left hemisphere. Compared to males, females were found to have anatomical parcels with higher SC in the left hemisphere involving the language network. Females were also found to have anatomical parcels with higher FC than males in the left hemisphere, including connections to the somatomotor and default mode networks, and lower FC distributed symmetrically between the two hemispheres. These findings highlight the sex differences in the brain structure and function in healthy, young adult populations that may underly behavioral and cognitive differences, including language processing and somatomotor perception.