Diffusion tensor imaging of rat brains following long-term passive acoustic exposure at moderate sound pressure level

Abstract

Diffusion tensor imaging was used to observe changes in the brain structure of rats (n=16) following two months of continuous and passive acoustic exposure at moderate sound pressure level. Voxel-based statistics (VBS) revealed greater fractional anisotropy of the pyramidal tract, tectospinal tract, intertwined trigeminothalamic tract and medial lemniscus of the exposed rats than of the control rats. ROIs were drawn for the structures indicated and applied to the fractional anisotropy and mean diffusivity maps. ROI analysis confirmed that in the structures indicated by VBS, fractional anisotropy was higher and mean diffusivity was lower in exposed rats than in normal rats.