DEPRESSION, PERSONALITY, AND GENDER INFLUENCE EEG, CORTISOL, BETA-ENDORPHIN, HEART-RATE, AND SUBJECTIVE RESPONSES TO SMOKING MULTIPLE CIGARETTES

EEG, hormonal, and subjective effects of smoking multiple cigarettes w ere assessed in 8 males and 8 females who smoked their own habitual br and of cigarette on one occassion, a nicotine-free control cigarette v ia a quantified smoke delivery system (QSDS) on another occasion, and standard cigarettes by means of a QSDS on two other occasions. Smoking nicotine-containing cigarettes decreased drowsiness and delta and the ta EEG magnitude while it increased serum cortisol. Nicotine enhanced beta2 magnitude significantly more in the right than left hemisphere. Nicotine-induced changes in serum cortisol, drowsiness, and EEG magnit ude correlated with each other, such that increases in cortisol correl ated with increased arousal. Prior to smoking, nicotine-deprived femal e nonsmokers, but did not differ in this regard after smoking. Female smokers also reported more trait depression than other participants. E xtraversion correlated positively with nicotine-induced decreases in d rowsiness, theta, and alpha EEG magnitudes, while neuroticism and depr ession correlated negatively with these changes. BDI depression score correlated with greater nicotine-free baseline EEG activation of the r ight than left hemisphere. Nicotine tended to eliminate (normalize) th is frontal EEG asymmetry that is characteristic of depressed individua ls.