MAPT and Mental deterioration: Alzheimer’s disease (AD) is the leading cause of dementia (Scheltens et al., 2016) characterised by extracellular β-amyloid plaques and intracellular neurofibrillary tangles of hyperphosphorylated tau, neuronal loss, and cognitive decline (Braak and Braak, 1991; Drummond and Wisniewski, 2017).