Effects of emotional arousal on the neural impact and behavioral efficacy of cigarette graphic warning labels

Background and Aims Graphic warning labels (GWLs) on cigarette packs have been adopted by many jurisdictions world‐wide. In the United States, the introduction of GWLs has been delayed by claims that their high level of negative emotional arousal unnecessarily infringed upon the tobacco manufacturers’ free speech. This study aimed to provide experimental data on the contribution of emotional arousal to GWL efficacy. Design Observational study using long‐term naturalistic exposure and functional magnetic resonance imaging. Setting Research university in Philadelphia, PA, USA. Participants A total of 168 adult smokers. Measurements For 4 weeks, participants received cigarettes in packs that carried either high‐arousal or low‐arousal GWLs (n = 84 versus 84). Smoking behavior, quitting‐related cognitions and GWL‐induced brain response were measured before and after the 4‐week exposure. The amygdala and medial prefrontal cortex served as regions of interest. Findings Compared with the high‐arousal group, the low‐arousal group smoked fewer cigarettes [log10‐transformed, 1.076 versus 1.019; difference = 0.056, 95% confidence interval (CI) = 0.027, 0.085, χ2(1) = 14.21, P