1. Departments of Neurology (Lee, C.E. Gamaldo, Dziedzic, Salas), Psychiatry and Behavioral Sciences (Peters, Roy, Buenaver), and Biology (Sierra-Arce, Vargas), Johns Hopkins Medicine, Baltimore; Human Development and Family Studies, Pennsylvania State University, State College, Pa. (A. Gamaldo); and Johns Hopkins University, Undergraduate Program in Public Health Studies, Baltimore (Chow).