In this study, smokers with schizophrenia and smokers without psychiatric illness participate in a nicotine preference task before and after a 3-day period of continuous smoking abstinence. The investigators will experimentally control abstinence by providing participants with high-value cash incentives contingent upon smoking abstinence verified with breath carbon monoxide levels. The investigators will measure nicotine withdrawal and smoking urge during the abstinence period. In the nicotine preference task, participants will make choices between nicotine-containing and denicotinized cigarette puffs to provide a measure of nicotine reinforcement, and the investigators will also measure the effects of smoking on mood. After the second nicotine preference task, participants will receive a small-value reinforcer if they continue to abstain for another day, and the investigators will measure time to the second lapse.