Fig. 2

Hypoperfusion was demonstrated in the orbitofrontal cortex, basal forebrain, and subgenual cingulate areas using IMP SPECT of the Easy Z-Score Imaging System, which is a voxel-by-voxel Z-score analysis after voxel normalization to the global mean values. Z-score = ([control population mean] – [individual value]/[control population standard deviation]), as displayed on the anatomically standardized MRI template. The colored areas demonstrate a significant decrease in regional cerebral blood flow. For example, red corresponds to a Z-score of −4.5 or less negative, i.e., most severely decreased, and blue corresponds to a Z-score between −3 and −2.5, i.e., less severely decreased