1. Department of Clinical and Behavioural Neurology, Santa Lucia Foundation, Rome, Italy
2. Department of Systems Medicine, Tor Vergata University of Rome, Rome, Italy
3. Department of Medicine, Center for Memory Disturbances, University of Perugia, Italy
4. Department of Experimental Medicine and Surgery, Tor Vergata University of Rome, Rome, Italy
5. C. Besta Neurologic Foundation, Milan, Italy
6. Epidemiology and Biostatistics Unit, Institute of Biomedical Technologies, National Research Council, Milan, Italy