Longchuan Li1, Todd M. Preuss2, James K. Rilling3,4, William D. Hopkins2, Matthew F. Glasser, Bhargav Kumar5, Roger Nana5, Xiaodong Zhang2, Xiaodong Hu1,5
1Biomedical Imaging Technology Center, School of Medicine, Emory University, Atlanta, GA, USA; 2Division of Neuroscience, Yerkes National Primate Research Center, Atlanta, GA, USA; 3Department of Anthropology, Emory University, Atlanta, GA, USA; 4Division of Psychobiology, Yerkes National Primate Research Center, Atlanta, GA, USA; 5Department of Biomedical Engineering, Georgia Institute of Technology/Emory University, Atlanta, GA, USA
Diffusion MRI was used to explore chimpanzees asymmetries in corticospinal system and their relationship with behavioral measures of handedness. Our results show that significant hemispheric asymmetries were observed at different levels of the corticospinal system in chimpanzees. Probabilistic tractography results suggest that the asymmetry in chimpanzees corticospinal system might be a combined result of the difference in hemispheric cortical connectivity and the asymmetry in white matter microstructure. A significant positive correlation between the asymmetry quiotent derived using DTI measure at the postcentral gyrus (PoG) and handedness indicates that the white matter microstructural asymmetry at the PoG reflects the functional lateralization of chimpanzees corticospinal system.