Characterization of topographic EEG changes when smoking a cigarette.

The acute effects of cigarette smoking on the human electroencephalogram (EEG) were investigated by the topographic mapping technique. Twenty-six subjects participated in this study, which involved sham smoking and real smoking of preferred cigarettes. Effects of smoking were analyzed by statistical and multivariate analysis. Analysis of variance and t-test results showed a significant decrease in the theta and alpha 1 bands but a significant increase in the alpha 2, beta 1, and beta 2 bands. Factor analysis and cluster analysis showed that there were two or three independent regions on the scalp that indicate the effects of smoking on topographic EEG. A hypothesis was formed that smoking has different effects on human EEG profiles for different brain regions and that there are individual variations in the EEG responses to smoking.