The effect of discount messages on impulse buying and self-control: investigating arousal through brain’s emotion signals

Background: This study investigated the impact of discount messages and individual self-control on arousal and Impulse buying behavior during purchasing processes. Methods: A laboratory experiment was conducted using a 2×3 between-subjects factorial design with 99 participants (mean age = 24.5, SD = 3.2; 52% female), randomly assigned to six experimental groups. The independent variables were self-control and discount message type (product-based discount, percentage discount, or no discount). Participants completed a simulated online shopping task while EEG data were recorded from 19 channels (10-20 system), focusing on frontal beta-to-alpha power ratios as a neural marker of arousal. Impulse buying was measured via post-experiment purchase intentions and actual checkout behavior. Data were analyzed using mediation analysis (PROCESS Model 4) with bootstrapping (5,000 samples). Results: The findings indicate that arousal did not significantly mediate the relationship between self-control and impulse buying. However, arousal significantly mediated the effect of product discount on impulse buying but not percentage discount. Furthermore, product discounts had a direct positive effect on impulse buying, while percentage discounts did not significantly influence impulse buying. These results highlight that discount type plays a crucial role in triggering arousal-driven impulse buying behavior. EEG analysis revealed that heightened arousal levels (beta-to-alpha ratios in frontal regions) corresponded with increased impulse Buying, reinforcing the role of arousal as a driver of emotional decision-making. Conclusion: These insights emphasize the need for marketing strategies that balance emotional engagement and consumer self-regulation. Businesses should consider differentiating discount types and promotional techniques to sustain consumer interest while mitigating post-purchase regret.