Cigarette smoking and nicotine gum (0, 2 and 4 mg): effects upon four visual attention tasks

Sixteen regular smokers, abstinent for 12 h prior to testing, were assessed on a battery of four visual attention tasks: rapid visual information processing (RVIP), letter cancellation, Stroop, and width of attention. Each subject was assessed under four conditions: placebo gum, 2 mg nicotine gum, 4 mg nicotine gum, and cigarette smoking (own brand), with the order of drug administration determined by latin square. Pre-post drug difference scores for letter cancellation response time demonstrated a significant monotonic dose-response function, with significantly faster performance following cigarette than placebo. RVIP response time and target detection were also affected by nicotine. One RVIP task parameter demonstrated a significant monotonic dose-response function, with highest performance under smoking. Other RVIP measures demonstrated curvilinear dose-response functions, with highest performance under nicotine gum, and broadly similar performance after placebo gum and cigarette smoking. Monotonic and inverted-U arousal/performance functions similar to these have been demonstrated in previous research with nicotine. In contrast to the significant changes in sustained attention, neither width of attention nor Stroop task performance (an index of distractability) was affected by nicotine. Resting heart rate and subjective 'need for a cigarette' showed the predicted monotonic dose-response functions following nicotine. There were no significant changes in any Profile of Mood State factor.