Figure 2. Imaging Only Top 20 Feature Importance results for Cognitive Flexibility Domain assessed using D-KEFS Trail Making – Number-Letter Switching Test.

Left Choroid Plexus volume (rank 2) was the important CSF feature in this model along with proximate projection and association white matter tracts that straddle the left lateral ventricle, including the left cingulum (paralimbic cortical association -radial diffusivity), the left cortical spinal tract (primary motor projection- fractional anisotropy), the left superior longitudinal fasciculus- (cortical association-fractional anisotropy) and the left arcuate fasciculus (cortical association fibers-fractional anisotropy), selected cortical grey matter structures, and more distal contralateral subcortical structures (right thalamus, right cerebellum and right hippocampus).