Effects of smoking on EEG alpha asymmetry during production of random sequences of numbers.

This study was conducted to evaluate the effects of smoking on EEG alpha asymmetry which occurs during the production of random sequences of numbers. The subjects were 10 students. The randomness of orally generated sequences was measured by the randomization index based on the Polya-Eggenberger distribution RIPE. The randomness decreased in the postsmoking sessions. Smoking increased EEG alpha asymmetry by reducing alpha activities in the left hemisphere (left-hemisphere activation) but not by increasing alpha activities (deactivation) of the right hemisphere. The self-reported stress related to task was lower in the postsmoking sessions. The cognitive facilitation model of smoking is discussed from a psychophysiological point of view.