 Objective: 1 To characterize physiological and affective condition, subjective state, cognitive performance, and concomitant changes in activation of specific brain regions blood oxygen level-dependent BOLD signal with fMRI after oromucosal administration of SativexRegistered Trademark and oral administration of THC. 2 To characterize the pharmacokinetics of THC and CBD and metabolites in plasma, urine, and oral fluid. 