[1] Oregon Hlth & Sci Univ, Dept Neurol, Portland, OR 97201 USA
[2] Univ Minnesota, Sch Med, Masonic Inst Dev Brain, Minneapolis, MN 55455 USA
[3] Univ Minnesota, Sch Med, Dept Pediat, Minneapolis, MN 55455 USA
[4] Univ Minnesota, Inst Child Dev, Sch Med, 51 E River Rd, Minneapolis, MN 55455 USA
[5] Oregon Hlth & Sci Univ, Dept Neurosurg, Portland, OR 97201 USA
[6] Northumbria Univ, Dept Sports Exercise & Rehabil, Newcastle Upon Tyne, Tyne & Wear, England
[7] Vet Affairs Portland Hlth Care Syst VAPORHCS, Portland, OR USA