Examples of the (A) projection fiber ROIs: corona radiata in magenta; internal capsule in green, (B) limbic fiber ROIs: cingulate gyrus in green, parahippocampal white matter in magenta; fornix in red, (C) association fiber ROIs: superior longitudinal fasciculus in red; superior fronto-occipital fasciculus in green; inferior fronto-occipital fasciculus in purple, and (D) corpus callosum ROIs: genu in purple; body in green; splenium in red.

<p>ROIs are overlaid an intensity-averaged FA template generated from 23 Aging Brain research participants with no infarct and WMH <0.5% intracranial volume.