Substitution for the discriminative stimulus effects of Δ9-THC: Dose-Effect. Upper panels show mean percentage of total responses (± standard error of the mean) made on the drug-appropriate lever as a function of dose, for doses with three or more rats completing the first fixed ratio. Bottom panels show rate of responding (± standard error of the mean) in responses per second (r/s). All of the cannabinoids fully substituted for the discriminative stimulus effects of Δ9-THC (>80% drug-appropriate responding). Sample size for BB-22, MAB-CHMINACA, NM2201, and 5F-AMB was n=6 except where shown; for FUB-PB-22, sample size was n=12. Ctrl indicates vehicle and drug control. * indicates response rate different from vehicle control (p < 0.05).