Human avoidance responding with added point loss: effects of tobacco and abstinence

Male smokers responded on a free-operant avoidance schedule with a response--point loss interval of 20 seconds and a point loss--point loss interval of 5 seconds. Unavoidable point losses were presented at variable times during the sessions. In Experiment 1 subjects were exposed to three tobacco abstinence conditions and an ad lib smoking condition. The conditions were nicotine gum, placebo gum, and no gum or cigarettes. In Experiment 2 subjects were administered tobacco smoke which delivered varying doses of nicotine. The smoke was administered by the spirometric method. Responding in each experiment was assessed during the session and also for 10 seconds following each of the unavoidable point losses. Results for Experiment 1 showed that the effect of smoke/nicotine abstinence on overall responding and for the interval following point losses differed across subjects. Results for Experiment 2 showed very little effect of acute nicotine dosing on the overall responding and varying effects on the responding during the interval following unavoidable point losses. These results are contrasted with previous research which has investigated tobacco smoke/nicotine abstinence and acute tobacco smoke dosing in experimental situations which were established as social via instructions.