 Male subjects with unipolar Major Depressive Disorder DSM-IV with a minimum score of 22 on the 10-item Montgomery-Åsberg Depression Rating Scale MADRS who were medication-free for at least 6 weeks, were enrolled. Fifteen individually age-matched 3 years healthy male controls with no history of psychiatric illness were also enrolled. Subjects ages ranged from 22- 55 y.o. mean S.D. 41.4 8.75 y.o.. All subjects were required to pass a urine toxicology screen assessing the presence of drugs of abuse on the day of testing. 