MAPT and Mental deterioration: When the second major AD pathology—Aβ plaques—is measured in the same patients, the deposition of Aβ and tau as measured by PET show distinct patterns throughout the AD brain (Sepulcre et al., 2016) with tau pathology showing a more direct correlation with neural network functional decline, cortical atrophy, and cognitive decline (Ishiki et al., 2015; Ossenkoppele et al., 2016; Schöll et al., 2016; Hoenig et al., 2018).