1. Department of Neurology, University of Wisconsin, Madison
2. Massachusetts General Hospital, Department of Neurology, Harvard Medical School, Boston, Massachusetts
3. Department of Neurology, Medical University of South Carolina, Charleston
4. Department of Neurology, Emory University, Atlanta, Georgia
5. Department of Neurology, Duke University, Durham, North Carolina
6. Hôpital Erasme, Département de Neurologie, Université Libre de Bruxelles, Bruxelles, Belgium
7. Department of Neurology, Yale University, New Haven, Connecticut