Schematic representation of different hypothesis of Alzheimer’s disease; Amyloid cascade hypothesis: β-amyloid monomers in the absence of proper signaling forms the β-amyloid plaques that cause neuronal dysfunction. Tau Hypothesis: Where increased production of hyperphosphorylated tau promote disintegration of microtubules and accumulation of hyperphosphorylated tau fibrils causing neural death. Cholinergic hypothesis: Disrupted Acetylcholine effect the synaptic function.