MAPT and Alzheimer disease: GM network measures start to change early in the disease process: previous studies indicate that the presence of Aβ significantly alters GM networks, and that these alterations may precede tau and neurodegeneration,48–51 and can predict future hippocampal atrophy.52 It could be hypothesized that the Alzheimer’s disease neuropathological changes contribute to the observed brain network disruptions, and represent a close biological substrate for disease progression and cognitive decline in Alzheimer’s disease.