Assessing Discrimination of Nicotine in Humans Via Cigarette Smoking

Abstract

The interoceptive stimulus effects of nicotine are critical to understanding reinforcement from cigarette smoking behavior. Because of the very recent availability of Spectrum research cigarettes from NIDA, with specific known amounts of nicotine content, the study of nicotine discrimination in humans via cigarette smoking may now be feasible. Our results demonstrate that, with sufficient training, smokers can behaviorally discriminate nicotine from four puffs' exposure between cigarettes differing in nicotine contents. Future research should evaluate human discrimination of nicotine from greater amounts of cigarette smoke exposure, as well as in response to other procedural variations.

Threshold dose for discrimination of nicotine via cigarette smoking

“…(Training conditions for these participants, all of whom learned to discriminate the two cigarettes most different in nicotine content, 16 mg/g vs 0.4 mg/g, as noted, varied slightly between the first 10 and last 8 subjects. Training involved 2 trials, one for each cigarette, for the first 10 subjects, and 4 trials, two for each cigarette, for the last 8 subjects, as explained elsewhere in the development of these procedures; Perkins et al in press. Threshold doses for those with 2 vs. 4 training trials were not different in this study, as indicated below in the Results.)…”

“…Eligible subjects were those 18 (out of 29) able to discriminate between the two Spectrum cigarettes most widely differing in nicotine content (see next section) and thus could provide a discrimination threshold dose (see Perkins et al in press). All were dependent smokers who preferred non-menthol cigarettes, to eliminate variability in one key non-nicotine constituent, menthol, that could alter discrimination behavior (a topic warranting focused research; e.g.…”

“…Holtzman 1990; Preston 1991; Rush et al 1995). The initial development and evaluation of these procedures for testing nicotine discrimination by tobacco smoking, once the Spectrum research cigarettes became available, are detailed elsewhere (Perkins et al in press). All study sessions involved testing for discrimination between the ultra-low 0.4 mg/g nicotine content cigarette versus one of the higher nicotine content Spectrum cigarettes (>1 mg/g).…”

Preliminary test of cigarette nicotine discrimination threshold in non-dependent versus dependent smokers

“…Spectrum investigational research cigarettes, manufactured by 22 nd Century Group (Clarence NY; http://www.xxiicentury.com/), were obtained from NIDA’s Drug Supply Program (see Perkins et al, 2016a). Selected for the current study were all those cigarettes that differed in nicotine contents but were similar on “tar” yield (so differing only in nicotine per se).…”

“…In contrast with commercial brands, these research cigarettes essentially prevent smokers from obtaining nicotine exposure different from the cigarette’s contents by altering their puff topography (see Hatsukami et al, 2013; Marian et al, 2009). Using Spectrum cigarettes, we adapted methods from our prior studies on nicotine discrimination with nasal spray (reviewed in Perkins, 2011) to develop procedures testing nicotine discrimination via cigarette smoking (Perkins et al, 2016a). Subsequently, we evaluated procedures for determining the threshold “dose” for discriminating nicotine in dependent smokers (Perkins et al, 2016b), followed by comparison of dependent smokers who preferred menthol vs. non-menthol cigarette brands (Perkins et al, under review).…”