1. Parkinson's and Movement Disorders Unit, Neurology Service, Hospital Clinic, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
2. Department of Psychiatry and Clinical Psychobiology, University of Barcelona, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
3. Neurosurgery Service, Hospital Clinic, Barcelona, Spain