aDivision of Neurology, Department of Pediatrics, Children's Hospital Los Angeles

bDepartment of Neurology, Keck School of Medicine of USC, Los Angeles, California

cDepartment of Pediatrics, University of Pittsburgh School of Medicine

dDivision of Child Neurology, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania

eDepartment of Neurology

fDivision of Developmental Medicine, Boston Children's Hospital, Boston, Massachusetts

gDepartment of Medicine

hDepartment of Psychiatry, University of Pittsburgh, Pittsburgh, Pennsylvania, USA

Correspondence to Jonathan D. Santoro, MD, Division of Neurology, Children's Hospital Los Angeles, Los Angeles, CA 90027, USA. Tel: +1 323 361 2471; fax: +1 323 361 1109; e-mail: [email protected]