Before concluding that smoking, or nicotine, has little effect on negative affect due to sources other than abstinence, other measures of affective response should be considered. As Perkins et al.
correctly point out, subjective measures of mood have their limitations. Physiological measures (e.g., cardiovascular, hormonal) have been utilized in prior studies to provide an objective assay of affective responses to stress. While there is some support for blunted cortisol responses to stress in smokers compared to non-smokers, the evidence for other physiological measures is mixed (8
). Further, there is little evidence to suggest that smoking reverses stress-induced changes in objective physiological indices. Thus, the findings of Perkins et al.
synergize with prior research using objective physiological measures, suggesting that effects of smoking and nicotine on stress-induced negative affect relief are modest at best.
Effects of smoking or nicotine on negative affective responses to emotional stimuli might be probed further, however, using neuroimaging approaches. For example, increases in amygdala activity correlate with self-reported smoking for calming effects (9
). Perhaps most germane to the study by Perkins et al.,
the negative affect reduction following smoking a nicotine versus a denicotinized cigarette is associated with increased smoking-induced dopamine release in a recent positron emission tomography study (10
). This line of research could be extended using functional neuroimaging paradigms involving exposure to affective stimuli (e.g., emotional faces, affect-laden images). Available evidence supports the sensitivity of this approach for assessing limbic reactivity to mood manipulations as well as sensitivity to the effects of short-term anti-depressant treatment (11
). The power of these approaches may lie in their greater sensitivity to detecting subtle affective responses that may nonetheless have important behavioral implications.