Effects of cigarette smoking on subjective and brain evoked responses to electrical pain stimulation.

The effects of smoking two cigarettes on brain evoked potentials (EP) and subjective ratings (SR) of pain intensity to 3 levels of electrical skin stimulation were investigated in 14 female habitual smokers. Smoking increased EP amplitudes to all stimulus intensities, but did not alter SRs. Changes in SRs to intensities in the pain range, but not in the prepain range, were found to be negatively correlated with smoke inhalation as measured by expired alveolar carbon monoxide (CO) elevations. No significant EP-smoking inhalation correlations were observed.