Effects of ABT-089 on Smoking Abstinence Symptoms and Reward

This Phase IIa within-subject, cross-over pilot study will evaluate the effects of ABT-089 (an experimental medication not approved by the FDA) when administered as 40mg oral once daily dose for 10 days, compared to placebo, on the following: abstinence-induced cognitive deficits, smoking withdrawal, smoking urges, smoking reward, and a brief, monitored quit attempt (\~4 days). The key cognitive domains include: working memory, sustained attention, and response inhibition.