| Objectives: Rejection sensitivity refers to the tendency of individuals to anxiously anticipate the rejection of others and overreact to the rejection clue,it is a significant predictor of depression,social anxiety,self-injurious and aggressive behaviors.Previous studies showed that individuals with rejection sensitivity have emotional dysregulation of social pain,and social emotional dysregulation may be an important factor affecting the development of serious psychological diseases in individuals with rejection sensitivity.Therefore,to prevent individuals with rejection sensitivity from developing into depression and other serious psychological diseases,intervention in emotional dysregulation of social pain could be considered.In addition,emotion regulation could be divided into explicit/conscious and implicit/automatic emotion regulation according to the form of the regulation goal.Previous imaging studies showed that the dorsolateral prefrontal cortex(DLPFC)and the ventrolateral prefrontal cortex(VLPFC)are involved in the process of emotion regulation.However,the current studies mainly focused on the relationship between the DLPFC/VLPFC and explicit emotion regulation,fewer studies have explored the causal relationship between the DLPFC/VLPFC and implicit emotion regulation.This study intended to explore whether high-definition transcranial direct current stimulation(HD-tDCS)activates the DLPFC or the VLPFC could promote the process of emotion regulation of social pain in individuals with rejection sensitivity by combining the event-related potentials(ERP).The effect of the DLPFC/VLPFC on implicit and explicit emotion regulation were further explored to clarify the causal role of the prefrontal cortex in different forms of emotion regulation.Methods:A total of 63 individuals with high rejection sensitivity were recruited from Anhui Medical University.Participants were randomly assigned to one of the following three groups: the rVLPFC group(n = 22),the rDLPFC group(n = 23),and the sham group(n = 18).All participants received active or sham HD-tDCS(2 mA,20 min,once a day for 10 consecutive days).Before the first day of intervention(pre-stimulation)and after the last day of the intervention(post-stimulation),all participants in three groups filled out questionnaires,then completed the emotion priming paradigm and the emotion regulation task,during which EEG data were recorded.The effect of HD-tDCS was evaluated by comparing behavioral and electrophysiological indicators before and after stimulation.In addition,one month after the completion of the last stimulation,the participants were followed up with questionnaires.Results:(1)In the emotion priming paradigm,the negative emotional score and the LPP amplitude of individuals in the implicit regulation condition was significantly fewer than the control condition,indicating that the implicit regulation of emotions can effectively reduce the social pain experience of individuals with rejection sensitivity.After the intervention of HD-tDCS,the negative emotional score and the difference of P3 amplitude between the two conditions were significantly decreased in the rDLPFC group compared with the sham group and rVLPFC group.It is suggested that HD-tDCS of DLPFC may reduce the negative emotional response to social pain in individuals with rejection sensitivity by promoting cognitive control during the process of implicit emotion regulation.(2)In the emotion regulation task,the negative emotional score of the individuals in the cognitive reappraisal condition was significantly fewer than the control condition,but no significant difference in the amplitude of LPP was found between the conditions,suggesting that the rejection sensitive individuals may have explicit difficulty in emotion regulation.After the intervention of HD-tDCS,the LPP amplitude in the cognitive reappraisal condition of rVLPFC group were significantly decreased compared with the sham stimulus group and rDLPFC activated group,indicating that HD-tDCS activated rVLPFC can directly improve the cognitive reappraisal process of rejection sensitive individuals.Conclusions: The results showed that the individuals with rejection sensitivity had an explicit emotion regulation deficit in social pain emotion,while their implicit emotion regulation function was good.Activation of rDLPFC and rVLPFC by HD-tDCS can effectively reduce the social pain experience of individuals with rejection sensitivity.In addition,the results of this study further suggest that rDLPFC activation may contribute to promoting the involvement of early cognitive resources in the implicit emotion regulation process of social pain,thus helping to reduce the subjective negative experience of individuals with rejection sensitivity,and the activation of rVLPFC can promote the use of explicit emotion regulation strategies(cognitive reappraisal)in individuals with rejection sensitivity. |
