Fig. 2.

Developmental sex differences in gray matter density. a Although gray matter density is similar at age 8 in males and females, gray matter density increases more rapidly in females than males throughout adolescence. This differential rate of development results in females having higher gray matter density across the entire brain. b Sex differences vary with age, with males and females showing no differences at 8 years of age. Females then began to show greater gray matter density across many regions soon thereafter. All data adapted with permission from ref. [21]