H. Stefan Bracha, M.D.: Dr. Bracha, a child and adolescent psychiatrist and
neuropsychiatrist, is Associate Professor of Psychiatry and Neurology at
the University of Arkansas for Medical Sciences, Little Rock. He is an
expert on prenatal brain development and dermatoglyphics and has writ-
ten more than 50 articles about neurobiological brain disorders. He
received clinical and research training at the Bronx VA Hospital, NIMH,
and the University of California, San Diego. In 1989 he was awarded the
Young Scientist Award by the National Alliance for the Mentally 111. Dr.
Bracha was responsible for research planning and data analysis of finger
ridge counts and other dermatoglyphic measures in the twin study.

Richard Coppola, D.Sc.: Dr. Coppola is Chief of the Neuro-Imaging Unit,
NIMH Neuroscience Center at St. Elizabeths Hospital. He has specialized
in imaging techniques and the processing of neurophysiological data for
studying brain activity. He has authored over 100 professional publica-
tions and been awarded a Commendation Medal and Outstanding Service
Medal by the U.S. Public Health Service. Dr. Coppola was responsible for
the collection of MRI and EEG data on the twins.

Terry E. Goldberg, Ph.D.: Dr. Goldberg, Chief of the Neuropsychology Unit,
NIMH Neuroscience Center at St. Elizabeths Hospital, is one of the lead-
ing researchers in neuropsychology, especially in individuals with serious
mental illnesses. He has published more than 100 professional papers and
abstracts, including reviews of this research area. Dr. Goldberg was
responsible for planning, coordinating, and analyzing the 3-hour battery
of neuropsychological tests administered to the twins.

Thomas F. McNeil, Ph.D.: Dr. McNeil is Professor and Chairman of the
Department of Psychiatry at the University of Lund, Sweden, where he
has been associated since 1970. He has published many professional
papers and book chapters on the relationship of obstetrical complications
to serious mental illnesses and is a world authority on this subject. Prior to
going to the University of Lund, Dr. McNeil was associated with the
Lafayette Clinic in Detroit. Dr. McNeil was responsible for the data analy-
sis on obstetrical complications in this study.

Patricia O. Quinn, M.D.: Dr. Quinn, Clinical Assistant Professor of Pediatrics
and Child Psychiatry at Georgetown University School of Medicine, is in the
private practice of developmental pediatrics. She has conducted research
and published professional papers on minor physical anomalies for 20
years. She is also coauthor of Putting on the Brakes: A Young People's Guide toUnderstanding Attention Hyperactivity Disorder

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