Mean diffusivity images, which were computed from the reconstructed diffusion tensor data, were aligned and brain structures were segmented using an automatic segmentation protocol developed at the UNC Neuro Image Research and Analysis Laboratory (NIRAL) (Lee et al., 2009). Following automatic segmentation, blinded investigators manually post-segmented selected regions of interest identified from the automatic segmentation, as well as measuring region volume using ITK-SNAP™ software version 1.8. Brain region boundaries were determined using the Brookhaven National Library 3-D MRI Digital Atlas Database of the adult C57BL/6 mouse (www.bnl.gov/medical/RCIBI/mouse).
