NICOTINE PREFERENCE IN SMOKERS AS A FUNCTION OF SMOKING ABSTINENCE

Overnight smoking abstinence increases desire to smoke and intensity o f smoking behavior in smokers, but it is not completely clear that thi s reflects an increase in reinforcement from the psychoactive effects of nicotine per se. We examined choice of nicotine vs. placebo via nas al spray (Study 1) and nicotine vs. nonnicotine cigarette puffs (Study 2) in separate groups of smokers during each of two sessions, followi ng overnight abstinence vs. no abstinence. In each study, subjects fol lowed a forced choice procedure in which they were instructed to self- administer six sprays/puffs from between the two nasal sprays/cigarett es every 15 min for 2 h following initial exposure to each. In Study 1 , choice of nicotine spray (1.5 mu g/kg per spray) increased significa ntly following abstinence vs. no abstinence (47+/-6% vs. 34 +/- 5%, re spectively, p < 0.05). This shift in choice was more pronounced in the subset of smokers (choosers, n = 9 out of 24) who selected nicotine o n more than 50% of choices on the abstinent day. Choosers exhibited gr eater responses to initial nicotine exposure on positive (e.g., pleasa nt, vigor) but not aversive (e.g., jittery, uneasy) subjective measure s, suggesting that greater positive reinforcement from nicotine per se predicted subsequent choice. In Study 2, abstinence similarly increas ed choice of nicotine vs. nonnicotine cigarette puffs (82 +/- 6% vs. 6 4 +/- 8%, p < 0.05), although nearly all subjects (12 of 13) preferred the nicotine cigarette following abstinence. These results indicate t hat choice of nicotine per se, isolated from tobacco smoke, increases significantly after overnight tobacco abstinence. Copyright (C) 1996 E lsevier Science Inc.