John Hewitt

Dr. Hewitt is Director of the Institute for Behavioral Genetics, and Professor of Psychology and Neuroscience. Much of his research has used cross-sectional and longitudinal studies of twins and families to elucidate the genetic and environmental influences on behavior, personality, and health. Recent research has focused on individual differences in behavior and cognition in childhood and adolescence, and vulnerability to drug use, abuse, and dependence.

He is currently a site PI for the twin study hub of the nationwide Adolescent Behavior Cognitive Development (ABCD) project, and for a recently initiated project to assess the impact of recreational cannabis legalization in a large cohort of adult twin volunteers who have participated in research since they were adolescents, before recreational cannabis was legalized in Colorado.