[1] Univ Virginia, Off Dean, Sch Med, Charlottesville, VA 22908 USA
[2] Univ Pittsburgh, Sch Med, Dept Neurol, Brain Trauma Res Ctr, Pittsburgh, PA 15261 USA
[3] Univ Pittsburgh, Sch Med, Dept Psychiat, Brain Trauma Res Ctr, Pittsburgh, PA USA
[4] Univ Pittsburgh, Sch Med, Dept Neurosurg, Brain Trauma Res Ctr, Pittsburgh, PA 15261 USA