1. Vanderbilt Sports Concussion Center, Vanderbilt University Medical Center, Nashville, TN, USA
2. Department of Neurological Surgery, Vanderbilt University Medical Center, Nashville, TN, USA
3. Department Neurology, Medical College of Wisconsin, Milwaukee, WI, USA
4. Department of Neurosurgery, Medical College of Wisconsin, Milwaukee, WI, USA
5. Department of Psychiatry, Vanderbilt University Medical Center, Nashville, TN, USA