1. From the Department of Neurology (R.S., V.P.-M.), Massachusetts General Hospital, Harvard Medical School, Boston; Centre for Neuromuscular Diseases (J.M.M., M.M.R.), Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, United Kingdom; Department of Neurology (D.T.), and Department of Radiology (P.A.D.), University of Iowa Health Care, Carver College of Medicine, Iowa City; Michigan Neuroscience Institute (B.A.M.), University of Michigan, Ann Arbor; Unit of Medical...