Fig. (5).

Hierarchy of the tissue classes used by EM Segmenter for vervet brain MRI segmentation. The shaded boxes correspond to the leaf nodes of the tree hierarchy. Each of the leaf nodes of the tree is assigned a spatial prior defined by the probabilistic atlas of the corresponding structure. The white boxes define the logical groups of the substructures. Class labels: background (BG), white matter (WM), gray matter (GM) and cerebrospinal fluid (CSF) (WGM class consists of WM, GM and CSF), cerebellum (CB), brainstem (BS), cortical GM (CGM), left and right sub-cortical GM (l/r-SGM), and subcortical structures of interest: caudate (CAU), putamen (PUT) and the hippocampus (HPC).