MAPT and Alzheimer disease: Behavioral abnormalities, cognitive decline as well as characteristic features of AD are detectable in old mice (e.g., Aβ accumulation Tau hyperphosphorylation, neuronal loss, dendritic spine density and microgliosis), but also in young adults (e.g., astrogliosis and spongiform degeneration patterns) (Morley et al., 2012a,b).