Healthy Control Sample (n = 30, phase 1; n = 15, phase 3; n=20, phase 5): Right-handed subjects (ages 18-55) will be selected who have not met criteria for any major psychiatric disorder, have no known first-degree relatives with mood disorders, and have a current score on the Hamilton Depression Rating Scale (HDRS; 17 item) in the not depressed range (less than or equal to 7). Control subjects will be matched to depressed subjects for age, gender, and education.