MAPT and supranuclear palsy, progressive, 1: However, the pattern of ARTAG in the grey matter has been shown to correspond to the independent patterns of pathologies in PSP, PiD and CBD and the presence of TSAs and GFAs adjacent to one another in the grey matter of FTLD-tau cases have been speculated to represent various stages of astrocytic maturation from GFAs to disease-specific astrocytic plaques and ramified astrocytes [65].