Others, instead, support the idea that it is mainly Tau that plays the major role in the etiopathology, essentially for two reasons: firstly because Tau tangles can be found in patients’ brain even when extracellular Aβ deposits are not present [57], and secondly because evidences proved that intracellular Tau tangles rather than Aβ deposits are the most neurotoxic species, mainly responsible of the serious neurotoxic effects, behavioral deficits and cognitive decline associated with the progression of the disease [38,58,59]. This evidence concerns the gene MAPT and Mental deterioration.