4. Define the temporal evolution of pathologies in the predementia phases of Alzheimer's disease. One of the last decade's paradigm shifts in neuroscience has been the realization that AD, and likely also other neurodegenerative diseases, starts with a prolonged predementia phase. AD even starts with an asymptomatic phase, when brain pathology is present in the absence of clinical symptoms. It has become clear that we need to better understand the temporal sequence of pathologic events in these disorders to be able to select the optimal disease stages for interventions in clinical trials with different disease-modifying therapies directed at specific pathologies.