MAPT and Alzheimer disease: Previous longitudinal, neuropathological and imaging studies suggest a multifactorial aetiology of WML [13, 16, 32, 33, 58, 62] including WM damage secondary to both SVD- related ischemia and cortical AD pathology, i.e., depositions of intracellular hyperphosphorylated tau (HPτ) and extracellular amyloid-beta (Aβ).