Peg Nopoulos, M.D., presented this talk at the sixth World Congress on Huntington's Disease, Rio de Janeiro, Brazil, September 16, 2013. Dr. Nopoulos is Professor of Psychiatry, Pediatrics and Neurology, and Vice Chair for Research, Department of Psychiatry, at the University of Iowa Hospitals in Iowa City, Iowa. Dr. Nopoulos is a physician-scientist. Her clinical work consists of taking care of patients with Huntington’s disease in Iowa’s HD Center of Excellence, where she has worked for the past ten years. Dr. Nopoulos’ research focuses on the study of brain and behavior using state-of-the-art neuroimaging techniques, specifically Magnetic Resonance Imaging (MRI). Dr. Nopoulos is interested in aspects of understanding the normal, healthy brain such as differences in brain structure and function between the sexes as well as understanding how the brain changes with development through adolescence. In regard to HD, she is interested in studying the effects of the Huntington’s gene on brain development.