Voxel-by-voxel comparison of FDG/PET brain images of patient groups with MCI, PD and PD-MCI and normal controls will be presented which reveal hyper- and hypometabolic regional differences between groups. Expression of specific AD-related metabolic pattern (ADRP) and Parkinson disease cognitive pattern (PDCP) recently identified using spatial covariance analysis with FDG/PET data, will be shown for individual subjects and its ability to differentiate between groups, and correlation with CSF biomarkers for AD will be discussed.