Sex differences in the temporal lobe white matter and the corpus callosum: a diffusion tensor tractography study

Abstract

We assessed sex differences in fractional anisotropy (FA) and mean diffusion (MD) of temporal lobe white matter (TLWM(FA), TLWM(MD)), TLWM asymmetry, and the relationship between TLWM asymmetry and FA and MD of the corpus callosum (CC(FA), CC(MD)) using diffusion tensor tractography. We found sex differences in the M D of both inferior longitudinal fasciculus (ILF); however, it disappeared after statistical adjustments for intracranial volume and CC(MD) variability. FA of the superior longitudinal fasciculus (SLF(FA)) and FA and MD of the ILF (ILF(FA), ILF(MD)) showed leftward asymmetry. In females, the asymmetry indices of SLF(FA) and the MD of the SLF were significantly correlated with CC(FA) and CC(MD), respectively, which may be related to sex differences in the hemispheric specialization for language. NeuroReport 21:73-77 (C) 2010 Wolters Kluwer Health vertical bar Lippincott Williams & Wilkins.