1. Center of Neurology, Hertie Insitute for Clinical Brain Research, University of Tuebingen, Tuebingen, Germany
2. Unit of Geriatric Rehabilitation, “P. Palagi' Hospital, Florence, Italy
3. Department of Rehabilitation Medicine, Prato Hospital, Prato, Italy
4. Unit of Gerontology and Geriatric Medicine, University of Florence, Florence, Italy