Human primary auditory cortex in women and men

Specific patterns of anatomical symmetry or asymmetry have been associated with sex differences in human brain structure and function. An observer-ind ependent cytoarchitectonic method for the quantification of cell volume den sities and areal borders was used to investigate the size and microstructur e of primary auditory cortex (Brodmann area 41) in female (n = 14) and male (n = 13) postmortem brains. The total brain volume-adjusted volume of the primary auditory cortex was significantly larger in women than in men bilat erally. Inverse asymmetry towards the right side, as opposed to well-known asymmetries towards the left side, was more frequent in women. Laminar cell volume densities of BA 41 showed no gender effect. The morphometric data c onfirm (in part) gender differences in the cerebral organization of primary auditory cortex. NeuroReport 12:1561-1565 (C) 2001 Lippincott Williams & W ilkins.