Influences of high-definition transcranial direct current stimulation (HD-tDCS) and cognitive reappraisal on emotions and aggression following social exclusion.

Social exclusion can trigger negative emotions and aggressive behavior, while emotion regulation strategies and neuromodulation techniques may mitigate these effects. This study employed a 2 × 2 factorial design to investigate the impacts of high-definition transcranial direct current stimulation (HD-tDCS) and cognitive reappraisal on emotions and aggression following social exclusion. Thirty-two university students were randomly assigned to four groups: active HD-tDCS + cognitive reappraisal, sham HD-tDCS + cognitive reappraisal, active HD-tDCS + no reappraisal, and sham HD-tDCS + no reappraisal. Results showed that active HD-tDCS significantly reduced aggressive behavior in both the Competitive Reaction Time Task and Job-relevant Evaluations Task, likely by enhancing prefrontal regulatory control. Cognitive reappraisal significantly decreased negative emotions but did not directly reduce aggressive behavior, suggesting a dissociation between emotional and behavioral regulation pathways. No significant interaction was found between HD-tDCS and cognitive reappraisal, possibly due to their independent neural mechanisms. These findings highlight the potential of HD-tDCS and cognitive reappraisal as interventions for social exclusion-induced aggression and emotional dysregulation.