ERP evidence on the regulation of negative emotions by verbal humor in subthreshold depression individuals

Verbal humor, which integrates both cognitive and affective aspects, has been shown to effectively regulate negative emotions. However, there is limited temporal evidence regarding the underlying mechanisms of this regulation in individuals with subthreshold depression. In light of the three stages involved in verbal-humor processing, this study aims to explore group differences in the neural mechanisms of negative emotion regulation through verbal humor between individuals with subthreshold depression and healthy controls. Thirty-nine participants provided two emotion ratings after exposure to negative priming words and after viewing either humorous or neutral regulating stimuli. Behavioral results indicated distinct differences in emotion ratings between conditions in both groups, with larger differences observed in the humorous condition, suggesting that verbal humor plays a significant role in regulating negative emotions. The ERP results revealed that activation of the N400 and LPP components was significantly enhanced under humorous conditions, reflecting the joint regulation of cognitive and affective aspects in verbal-humor processing. Compared to healthy controls, the subthreshold depression group exhibited overall less N400 activation in the right central region. The LPP evoked in individuals with subthreshold depression was significantly lower compared to controls in neutral conditions, with no significant difference observed in the humorous condition. ERO results further demonstrated the effect of subthreshold depression on oscillatory changes in the regulation of negative emotions through verbal humor, showing that the subthreshold depression group exhibited lower activation in the theta and beta bands. Collectively, these results affirm that verbal humor can regulate negative emotions in individuals with subthreshold depression, albeit to a somewhat lesser extent within this group. Regarding the cognitive aspect of verbal humor, individuals with subthreshold depression exhibited a diminished ability to detect incongruities. Additionally, concerning the affective aspect of verbal humor, individuals with subthreshold depression showed a reduced tendency to engage with positive emotions. Future research could further explore the neural mechanisms by which individuals with subthreshold depression utilize verbal humor to regulate negative emotions.