1. Department of Neurology, Medical University of South Carolina, Charleston, SC, USA
2. Division of Sleep Medicine, Department of Neurology, University of Michigan, Ann Arbor, MI, USA
3. Division of Multiple Sclerosis and Clinical Neuroimmunology, Department of Neurology, University of Michigan, Ann Arbor, MI, USA/VA Ann Arbor Healthcare System, Ann Arbor, MI, USA
4. Divisions of Multiple Sclerosis, Clinical Neuroimmunology and Sleep Medicine, Department of Neurology, University of Michigan, Ann Arbor, MI, USA/Division of Multiple Sclerosis and Clinical Neuroimmunology, Department of Neurology, University of Michigan, Ann Arbor, MI, USA/VA Ann Arbor Healthcare System, Ann Arbor, MI, USA