1. Department of Hearing and Speech Sciences, Vanderbilt University Medical Center , Nashville, TN 37232 , USA
2. Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center , Nashville, TN 37232 , USA
3. School of Medicine, Vanderbilt University , Nashville, TN 37232 , USA
4. Department of Neurology, Vanderbilt University Medical Center , Nashville, TN 37232 , USA
5. Vanderbilt Stroke and Cerebrovascular Center, Vanderbilt University Medical Center , Nashville, TN 37232 , USA