[1] NIAAA, Intramural Res Program, NIH, Bethesda, MD 20892 USA
[2] NIDA, Intramural Res Program, NIH, Bethesda, MD 20892 USA
[3] NIH, Intramural Res Program, Ctr Compuls Behav, Bethesda, MD 20892 USA
[4] Univ Minnesota, Dept Neurosci, Minneapolis, MN 55455 USA