1. Faculty of Medicine, University of Pisa, Pisa, Italy.
2. Department of Human and Environmental Sciences, University of Pisa, Pisa, Italy.
3. Department of Neuroscience, University of Pisa, Pisa, Italy.
4. Department of Neurological and Psychiatric Sciences, University of Florence, Florence, Italy.
5. Division of Geriatrics, Department of Internal Medicine, University of Pisa, Pisa, Italy.