MAPT and Alzheimer disease: As secondary outcomes, we analyzed the relationship between CR proxies and functional network efficiency (resting-state fMRI graph metrics) in healthy controls, aMCI and mild AD patients; the relationship between pathophysiology (CSF Aβ, total tau (t-tau) and p-tau levels) and functional network efficiency in aMCI and mild AD patients; and the relationship between pathophysiology and CR proxies in aMCI and mild AD patients.