A conditioning theory of tolerance postulates a mechanism of a conditioned compensatory response which both modulates the effect of the drug and produces cravings when the drug is not forthcoming. Using measures of heartrate and peripheral vasodilation the author investigated whether reactions opposite in direction to the effects of nicotine such as bradychardia and peripheral vasodilation could be elicited specifically with smokers who are presented with smoking-related stimuli. Due to confounding variables supportive data were not obtained. Recommendations are to conduct future experiments when there is a low differential temperature between the outside and inside, incorporating a more salient conditioned stimulus so control over the conditioned response could be stronger and including more subjects to aid statistical analysis.