1. Department of Neurology; Johns Hopkins University School of Medicine; Baltimore Maryland U.S.A.
2. Tulane University School of Medicine; New Orleans Louisiana U.S.A.
3. Department of Neurology; University of Maryland School of Medicine; Baltimore Maryland U.S.A.
4. Department of Neurology; Sinai Hospital of Baltimore; Baltimore Maryland U.S.A.
5. Medical Advisory Board; Maryland Motor Vehicle Administration; Glen Burnie Maryland U.S.A.
6. University of Pittsburgh School of Medicine; Pittsburgh Pennsylvania U.S.A.