MAPT and Alzheimer disease: This second phase of data acquisition includes 6 years of additional follow‐up cognitive data, and additional MRI follow‐ups, clinical progression, new longitudinal behavioral and lifestyle measures (questionnaires, actigraphy), longitudinal AD plasma biomarkers, amyloid‐beta (Aβ) and tau positron emission tomography (PET), magnetoencephalography, as well as neuroimaging analytic measures from all MRI modalities.