The prevalence, age of onset, and symptomatology of many neuropsychiatric conditions differ between
males and females. To understand the causes and consequences of sex differences it is important to estab-
lish where they occur in the human brain. We report the first meta-analysis of typical sex differences on
global brain volume, a descriptive account of the breakdown of studies of each compartmental volume
by six age categories, and whole-brain voxel-wise meta-analyses on brain volume and density. Gaussian-
process regression coordinate-based meta-analysis was used to examine sex differences in voxel-based
regional volume and density. On average, males have larger total brain volumes than females. Exami-
nation of the breakdown of studies providing total volumes by age categories indicated a bias towards
the 18–59 year-old category. Regional sex differences in volume and tissue density include the amyg-
dala, hippocampus and insula, areas known to be implicated in sex-biased neuropsychiatric conditions.
Together, these results suggest candidate regions for investigating the asymmetric effect that sex has on
the developing brain, and for understanding sex-biased neurological and psychiatric conditions