A novel abuse liability assessment of e-cigarettes in young adults ii: Reinforcement enhancement and follow-up assessment.

A double-blind study was performed to test the abuse liability of electronic nicotine delivery systems (ENDS) in young adults; in particular, the influence of nicotine on reward sensitivity was assessed. A total of 53 healthy nonusers participated in experimental sessions during which they played a video game made available on a progressive ratio schedule of reinforcement and self-administered nicotine via ENDS. Participants were randomized into one of three groups.