MAPT and Alzheimer disease: In preclinical Alzheimer’s disease: Conceptual and biomarker advances over the past decade have led to the identification of a preclinical phase of AD, recently formalized by new diagnostic criteria that integrate biomarkers for brain amyloidosis (i.e. CSF Aβ42 and Aβ PET) and neurodegeneration (CSF tau, regional atrophy, and [18F]fluorodeoxyglucose ([18F]FDG) PET) [66, 67, 79, 80].