MAPT and Brain atrophy: These biomarkers include the reduction of β-amyloid 42 (Aβ42), elevations of phosphorylated tau and total tau in cerebrospinal fluid, glucose hypometabolism of temporal and parietal cortex assayed by 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET), Aβ deposition in brain cortices examined by 11C-Pittsburgh compound B (11C-PiB) PET and brain atrophy measured by MRI [1].