MAPT and Alzheimer disease: The negative correlation between MBI and tau pathology in the case of absence of amyloid abnormality in this study suggests that other pathologies, such as vascular, TDP-43, non-helical tau, only 3R or 4R tauopathies (and not the paired helical filament form, or the combination of 3R and 4R tau forms observed in AD, detected with AV145Cby tau PET in this study) would underlie the pathophysiology of MBI [65].