Cynthia Kuhn, PhD, professor of pharmacology, cancer biology, psychiatry and behavioral sciences at Duke University School of Medicine in Durham, North Carolina, where she studies the biologic factors that increase sensitivity to drug abuse and depression. Dr. Kuhn is also coauthor, with Scott Swartzwelder, PhD, and Wilkie Wilson, PhD, of Buzzed: The Straight Facts About the Most Used and Abused Drugs from Alcohol to Ecstasy(Norton).