1 Institute of Neurology, Catholic University, Rome, Italy.
2 Morton and Gloria Shulman Movement Disorders Centre and the Edmond J. Safra Program in Parkinson's Disease, Toronto Western Hospital, UHN, Division of Neurology, University of Toronto, Toronto, Ontario, Canada; Krembil Research Institute, Toronto, Ontario, Canada.
3 Institute of Neurology, Catholic University, Rome, Italy. Electronic address: [email protected].