There is considerable debate over the effect of nicotine on human emotion and performance. Some studies suggest that nicotine facilitates performance while elevating overall mood, while others suggest just the opposite. Recent data indicate that learning history plays a significant role in nicotine's effects on performance and emotion. However, previous investigations have not examined the influence of drug withdrawal or subject's drug state during training trials prior to experimental manipulation. Thirty smokers were randomly assigned to one of three groups: 1) No-smoking/Deprived, 2) Smoking/ Nondeprived, and 3) No-smoking/Nondeprived. Subjects underwent 13 nicotine-free training trials on the computerized Walter Reed Performance Assessment Battery (PAB). Subjects completed the Profile of Mood States (POMS), Emotion Assessment Scale (EAS) and a tobacco withdrawal rating scale as indication of moodstate. The No-smoking/Deprived group did not smoke, thus remained drug-deprived. The Smoking/Nondeprived group smoked ad libitum during the final test P AB in order to "cross" their drug state from the training trials. The No-smoking/ N ondeprived group smoked four puffs before the test P AB in order to partially alleviate their state of drug withdrawal, but did not smoke during the test P AB to maintain drug state consistency between training and test trials. While improvements were noted on subjective mood ratings and withdrawal symptoms following smoking, there was little evidence that overall performance was effected. Overall, the results of the present study suggest that the pharmacological aspects of nicotine may outweigh the role of learning and conditioning in human performance and emotion.Clinical Psycholog