Figure 2

Cortical location of the hypometabolic areas. X axis presents the number of hypometabolic areas using visual analysis (n = 86) and of hypometabolic clusters (true hypometabolic areas and artifacts) using SPM-P (n = 83) and SPM-A (n = 120), according to their regional location on the cortex: F, frontal; C, central or opercular; P, parietal; T, temporal or insular; O, occipital. Y axis presents the number of hypometabolic areas among the 470 regions visually analyzed (47 patients, ten regions/patient). Notice that visual analysis is equal or superior to SPM to identify a hypometabolic area in any region, and both SPM procedures are quite equivalent to identify a true hypometabolic cluster in any region, but SPM-A identifies more artifacts than SPM-P, particularly in the frontal and temporal cortices, the most frequent hypometabolic locations.