Twenty-nine healthy, right-handed volunteers (twelve males; aged 21–45 years; Caucasian = 21; African American = 4; Asian = 2; More than one race = 2) participated in this study and were randomly assigned to the THC (n = 14) or placebo (n = 15) condition. Some participants (n = 13) had a minimal history of marijuana use (limited to < 10 lifetime exposures; mean: 1.2 ± 0.44); none had history or signs of neurological, psychiatric (including substance and alcohol abuse/dependence), or medical illness as confirmed by medical examination and a modified Structured Clinical Interview for DSM-IV (SCID-NP; (First et al., 2002)). All subjects had negative urine toxicology and alcohol breathalyzer screens at time of study.
