Children and adolescents ages nine to eighteen will be allowed into the study. Subjects entering the protocol as new patients will be characterized by clinical phenomenology, eye tracking, MRI brain imaging, cerebrospinal fluid, plasma and urinary biochemistry, and chromosomal analysis. Patients with prominent mood symptoms who have required the addition of mood stabilizing agents such as lithium or valproic acid will be allowed to remain on these medications for the duration of the treatment trial, if clinically indicated. Liver chemistries will be checked at baseline and at the end of the study.