Attentional biases toward drug-related stimuli may contribute to drug use and relapse in addicts by selectively facilitating the processing of drug-related information at the expense of other information. This could lead to increased craving and/or activation of drug-use action patterns, much as exposure to food-related stimuli can increase subjective hunger and feeding behavior in normal subjects. The proposed research investigates the effects of motivationally-salient word stimuli (food-related in normal subjects and smoking-related in nicotine-dependent smokers) on the focus of visuospatial attention under deprived (i.e. 12-hour fast/abstinence) and undeprived conditions. Subjects perform a task in which motivationally-salient and neutral word cues focus attention on the likely location of response targets. Previous studies show a validity effect with motivationally-neutral cues, i.e. when cues correctly indicate upcoming target location (valid trials), targets elicit faster reaction times (M) and larger amplitude early visual ERP components (P1 and N1) than when cues are misleading (invalid trials). Experiment I assesses the effects of food word cues on the RT validity effect in normal subjects. Experiment II replicates and adds cue and target ERP measures. Experiment III uses the Experiment II design to assess the effects of smoking word cues in nicotine-dependent smokers. Predictions: more so under deprived than undeprived conditions, 1) an ERP component sensitive to stimulus-evaluation factors (P3), will have greater amplitude when evoked by smoking/food cues than by neutral cues; 2) smoking/food cues will elicit more focused attention to locations than neutral cues, exaggerating RT and P1/N1 validity effects.
