1 Department of Clinical Neuroscience, Umeå University, Umeå, Sweden.
2 UCL Queen Square Institute of Neurology, London, United Kingdom.
3 Department of Neurology, UCLA David Geffen School of Medicine, Los Angeles, California, USA.
4 Neurosurgery Department at The Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA.
5 Department of Neurology, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam Neuroscience, Amsterdam, the Netherlands.
6 Department of Neurology, Emory University School of Medicine, Atlanta, Georgia, USA.
7 Department of Neurosurgery, Emory University School of Medicine, Atlanta, Georgia, USA.
8 Department of Neurology, Inselspital, University Hospital Bern, Bern, Switzerland.
9 Department of Neurosurgery, Medical School Hannover, Hannover, Germany.
10 The Edmond J. Safra Program in Parkinson's Disease and the Morton and Gloria Shulman Movement Disorders Clinic, Toronto Western Hospital & University of Toronto, Toronto, Ontario, Canada.
11 Division of Neurosurgery, Department of Surgery, University of Toronto, Toronto, Ontario, Canada.
12 HM CINAC (Centro Integral de Neurociencias Abarca Campal), Fundación Hospitales de Madrid, Hospital Universitario HM Puerta del Sur, HM Hospitales, Madrid, Spain.
13 Network Center for Biomedical Research on Neurodegenerative Diseases (CIBERNED), Instituto Carlos III, Madrid, Spain.
14 University CEU-San Pablo, Madrid, Spain.
15 Department of Neurosurgery, Amsterdam UMC, Amsterdam, the Netherlands.
16 Department of Neurology, University of Minnesota, Minneapolis, Minnesota, USA.