MAPT and Alzheimer disease: The age-dependent accumulation of Aβ and hyperphosphorylated/cleaved tau protein, along with other structural and functional synaptic and metabolic changes classically taking place in AD brains, are also detected in the eyes of animal models [2,11,12,13,14,15] and affected patients [4,16,17,18,19,20,21,22,23,24].