1. From the Department of Pediatrics (R.G.-S.), University of Michigan, Ann Arbor; Department of Neurology (K.X.), University of Virginia, Charlottesville; Department of Neurology (J.M.M.), Wake Forest University School of Medicine, Winston-Salem, NC; Department of Neurology (J.H.R.G.), University of Minnesota, Minneapolis; and Department of Neurology (J.R.), University of Rochester, NY.