MAPT and Alzheimer disease: Moreover, MTL tau accumulation in cognitively normal elderly is associated with patterns of neurodegeneration as assessed by both structural magnetic resonance imaging (MRI) and [18F] Fluorodeoxyglucose (FDG) PET that are topographically similar to the patterns seen in AD patients [2, 74, 125, 132, 176], suggesting that early-stage MTL tau might have a pathogenic role even in cognitively healthy individuals.