Effects of tobacco smoking on electroencephalographic, auditory evoked and event related potentials.

After overnight abstinence, tobacco smokers smoked an average nicotine yield cigarette and nonsmokers sham smoked an unlit placebo cigarette. EEG alpha(1), delta, and theta frequency amplitudes decreased, whereas alpha(2) and beta frequency amplitude increased. Short, middle (EP) and long latency ERP were also studied in nonsmokers and smokers just after smoking, and after overnight abstinence from tobacco. Short latency potentials were unaffected by tobacco smoking or abstinence. Middle and long-latency potentials were reduced during abstinence and enhanced immediately after tobacco smoking. These findings indicate that compared to nonsmokers smokers have a higher arousal level after smoking than when partially abstinent. Evidence for both normalization from tobacco abstinence as well as stimulation was obtained.