EFFECTS OF NICOTINE ON PERCEPTUAL SPEED

Two experiments investigating the effects of nicotine on performance i n the inspection time (IT) procedure are reported. Experiment 1 compar ed ITs in smoking (0.8 mg nicotine cigarette), sham-smoking, and no-sm oking conditions. IT was significantly shorter in the smoking conditio n as compared to both the no-smoking or sham-smoking conditions, sugge sting that nicotine enhances early information processing. This result is of particular interest because of the correlation between IT and I Q reported in previous experiments. The nicotine related decrease in I T raises the possibility that nicotine enhances at least a subset of t he physiological processes underlying intellectual performance. Experi ment 2 examined the persistence of this nicotine related enhancement i n IT, and investigated the effects of nicotine across 480 IT trials. R esults suggested that ITs derived from the last third of the 480 trial s were significantly shorter in the 0.8 mg cigarette condition than in no-smoking condition. The results from these two experiments, taken t ogether with recent work examining the effects of nicotine on the stri ng length measure of AEP waveform complexity and Hick decision time (D T), and studies investigating cognitive functioning and cholinergic sy stem dysfunction in dementia, suggest a role of the cholinergic system in intellectual performance.