Laterality and aging of thalamic subregions measured by diffusion tensor imaging.

Thalamic nuclei are comprised of fibers connecting associated cortical regions, and abnormalities of the thalamus are correlated with abnormalities in cognition and behavior. Some previous studies showed the laterality of the whole thalamus and the regional differences among thalamic nuclei. This led us to assess regional characteristics in five major subregions of both sides of the thalamus using diffusion-tensor imaging. Statistically significant lateralities and regional differences were found among the thalamic subregions. Age has a significant correlation with diffusion-tensor imaging metrics where their projection areas are thought to be vulnerable to normal aging. Our results confirmed that the thalamic subregions behave independently, and their respective microstructures warrant further investigations.