1Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, United States, 2F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD, United States, 3International Center for Spinal Cord Injury, Kennedy Krieger Institute, Baltimore, MD, United States, 4Physical Medicine and Rehabilitation, Johns Hopkins University School of Medicine, Baltimore, MD, United States, 5Radiology and Radiological Sciences, Vanderbilt University, Nashville, TN, United States, 6Vanderbilt University Institute of Imaging Science, Vanderbilt University, Nashville, TN, United States, 7Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, United States