[1] McLean Hosp, Div Alcohol & Drug Abuse, Belmont, MA 02478 USA
[2] Harvard Univ, Sch Med, Dept Psychiat, Boston, MA 02115 USA
[3] McLean Hosp, Lab Psychiat Biostat, Belmont, MA 02478 USA
[4] Yale Univ, Sch Med, Dept Psychiat, West Haven, CT 06516 USA
[5] Univ Pittsburgh, Sch Med, Dept Anesthesiol, Pittsburgh, PA 15206 USA
[6] Univ Pittsburgh, Sch Med, Dept Psychiat, Pittsburgh, PA 15206 USA