1. Gordon Center for Medical Imaging, Department of Radiology Massachusetts General Hospital, Harvard Medical School Boston Massachusetts USA
2. Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology Massachusetts General Hospital, Harvard Medical School Charlestown Massachusetts USA
3. Memory Unit, Department of Neurology Hospital de la Santa Creu i Sant Pau, Biomedical Research Institute Sant Pau, Universitat Autonoma de Barcelona Barcelona Spain
4. Centro de Investigacón Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED) Spain