Effects of nicotine and caffeine, separately and in combination, on EEG topography, mood, heart rate, cortisol, and vigilance

Abstract

Effects of nicotine and caffeine, separately and in combination, were assessed in 12 male habitual smokers in a repeated-measures design. Caffeine (0-mg vs. two 150-mg doses administered in a decaffeinated/sugar-free cola drink post-baseline and 90 min later) was crossed with nicotine (ad libitum own dosing vs. 1.0-mg machine-delivered dose vs. 0.05-mg machine-delivered dose). Participants smoked a total of five cigarettes at 30-min intervals over a 2-hr period. Caffeine and nicotine had large effect sizes on electroencephalogram (EEG) power; however, these effects were modulated by the eyes open versus closed condition, the other drug, and electrode site. EEG effects of open versus closed eyes tended to be of the same size and direction as those of nicotine and caffeine. However, whereas nicotine increased EEG power in some higher frequency bands in some conditions, caffeine decreased EEG power across almost all conditions. Serum cortisol concentration, vigor, and pleasantness were increased by nicotine, but not by caffeine. Level of depressive mood depended on an interaction of caffeine and nicotine. Vigilance performance was enhanced significantly by caffeine and was increased almost significantly by nicotine. The findings were interpreted in terms of common and differential mechanisms of the two drugs.

Caffeine effects on resting-state arousal in children

“…Presynaptic adenosine receptors occur on virtually all types of neurons (Lorist and Tops, 2003), supporting a widespread arousal function, consistent with the common view of caffeine's primary effect (Flaten and Blumental, 1999;Lyvers et al, 2004). Caffeine consistently increases SCL (Bruce et al, 1986;Zahn and Rapoport, 1987;Flaten and Blumental, 1999;Gilbert et al, 2000;Quinlan et al, 2000), as we confirmed with 200 mg caffeine in adults (Barry et al, 2005b(Barry et al, , 2008.…”

Electroencephalographic abnormalities in antisocial personality disorder

“…33e35 Increase of alpha power had been reported as a nicotine effect in rest EEG with closed eyes. 34,35 A decrease in alpha activity was found in this study. The result is consistent with findings from other studies where violent individuals had been involved.…”

“…36 Therefore it is probable that alpha decreasing observed may be higher without the influence of the nicotine over the EEG activity. With regard to caffeine, studies designed to characterize the effects of caffeine on EEG had showed increase of beta power, 35,37,38 as the outcome of this research found in the ASPD group. Nevertheless, there is a very low level of consumption of this legal drug during the permanence in prison (at least in Cuba), that is why it is considered that caffeine effects were not responsible for the increase of beta power in the ASPD group.…”

Smoking, arousal, and affect: The role of anxiety sensitivity

“…Studies have found that smoking reliably increases heart rate (HR) (Byrne, 2000;Gilbert, Meliska, Welser, & Estes, 1994;Masson & Gilbert, 1999), blood pressure (Dembroski, MacDougall, Cardoza, Ireland, & Krug-Fite, 1985;MacDougall, Dembroski, Slaats, Herd, & Eliot, 1983;Perkins, Epstein, Jennings, & Stiller, 1986), serum cortisol concentration (Gilbert, Dibb, Plath, & Hiyane, 2000;Gilbert et al, 1994;Pomerleau & Pomerleau, 1990) and skin conductance (SC) (Byrne, 2000;Perkins, Grobe, Fonte, & Breus, 1992). These physiological indices are believed to be associated with states of stress and anxiety.…”