Effects of nicotine on olfactogustatory incentives: preference, palatability, and operant choice tests.

Introduction: The use of additives in tobacco may capitalize on the incentive motivational properties of tastes and scents such as mint (menthol), vanilla, and strawberry. These incentives are intended to increase tobacco experimentation, but their salience may also be enhanced by the incentive amplifying effects of nicotine (NIC). The goal of the present studies was to investigate the potential interaction between the incentive amplifying effects of NIC and gustatory incentives.

Methods: One of two discriminable tastes (grape or cherry Kool-Aid®; 0.05% wt/vol; unsweetened) was paired with sucrose (20% wt/vol; conditioned stimulus [CS+]) in deionized water, whereas the other taste (CS-) was presented in deionized water. Experiment 1 investigated the effects of NIC pretreatment on preference for the CS+ versus CS- in 2-bottle choice tests. Experiment 2 investigated the effects of NIC on palatability of the CS+ and CS- using orofacial taste reactions. Experiment 3 investigated the effects of NIC on reinforcement by the CS+ and CS- using a concurrent choice operant task.

Results: NIC pretreatment robustly increased operant responding for the CS+ but did not alter responding for the CS- in the operant choice task (Experiment 3). However, NIC pretreatment did not alter intake or palatability of the CS+ or CS- (Experiments 1 and 2).

Conclusions: NIC increases the reinforcing effects of gustatory incentive stimuli, even though these stimuli were not paired with NIC administration. The findings suggest that adding taste incentives to tobacco products may increase the attractiveness of these products to consumers and the probability of repeated use.