AbstractThe effects of caffeine and smoking on cognitive performance, subjective variables, heart rate, and EEG were assessed in two sessions. In one session, subjects received caffeine (2.5 mg/kg bodyweight), while in the other they received placebo. In both sessions (hey smoked a cigarette (8 cued puffs) having a nicotine yield of 1.2 mg. Caffeine produced an increase in self‐reported muscular tension and tended to increase anxiety and delta magnitude. Smoking facilitated performance of a paper‐and‐pencil math task and increased heart rate. Smoking also appeared to produce cortical activation as indexed by decreased right frontal delta, decreased right centro‐parietal theta, globally increased alpha, and increased centro‐occipital/decreased posterior‐temporal betal. Smoking also increased central/decreased posterior‐temporal beta2. Smoking and caffeine did not interact for any measure, suggesting that the epidemiological link between smoking and coffee drinking may have a non‐pharma