1. Vita-Salute San Raffaele University, Milan, Italy
2. Human Molecular and Structural Neuroimaging Unit, Division of Neuroscience, IRCCS San Raffaele Scientific Institute, Milan, Italy
3. Memory and Aging Center, Weill Institute for Neurosciences, University of California San Francisco, San Francisco, CA, USA
4. Nuclear Medicine Unit, San Raffaele Hospital, Milan, Italy