Spontaneous EEG changes during tobacco abstinence and nicotine substitution in human volunteers.

Electroencephalographic correlates of tobacco abstinence and nicotine substitution were measured in adult male cigarette smokers in residence on a research ward in two experiments. After ad libitum smoking, seven subjects were deprived of nicotine for 10 days and then resumed smoking. During tobacco abstinence, there were significant decreases in alpha frequency and beta frequency and increases in theta power. These effects were observed as early as 29 hr and in some instances persisted for 7 days. In the second experiment, a group of eight heavy smokers chewed 12 pieces of either placebo or nicotine-containing polacrilex gum (2 or 4 mg) per day while deprived of cigarettes. In the placebo condition, electroencephalographic signs were similar to those accompanying tobacco deprivation in the first experiment. Administration of nicotine polacrilex prevented the appearance of these tobacco withdrawal signs. This study provides new information on the time course of certain electrophysiologic components of the tobacco withdrawal syndrome and confirms that the effects are specific to the deprivation of nicotine. The data also suggest that the 4-mg polacrilex was more effective than the 2-mg dose when the results across all measures were considered.