The Intrapersonal Functional Connectivity And Interpersonal Brain Synchronization During Interpersonal Emotion Regulation Of Negative Emotions

Interpersonal emotion regulation refers to the intentional influence individuals exert on their own or others’emotional experiences through social interactions.However,empirical research in this field have explored little about the neural basis of negative emotion regulation in the context of interpersonal interaction.This study focused on female friends,and in each friend dyads,one was randomly designated as the target while the other as the regulator used interpersonal emotion regulation strategies（cognitive reappraisal vs.expressive suppression）strategies to down-regulate the target’s negative emotions.Based on the communication theory and process theory of interpersonal emotion regulation,we divided interpersonal emotion regulation into three interaction stages artificially:emotion elicitation,emotion sharing and emotion regulation.Two f NIRS-based experiments were conducted to address the following questions during the regulation of interpersonal in sadness and anger:（1）the differences in regulation effects between cognitive reappraisal and expressive suppression strategies;（2）The differences in intrapersonal functional connectivity and interpersonal brain synchronization between regulators using cognitive reappraisal and expressive suppression strategies;（3）The interactive effects of regulation strategies（cognitive reappraisal vs.expressive suppression）and regulation stages（emotion elicitation vs.emotion sharing vs.emotion regulation）on intrapersonal functional connectivity and interpersonal brainA total of 80 female friends’dyads(M_age=21.52,SD=2.173)participated in Experiment 1.They were randomly assigned to cognitive reappraisal or expressive suppression group and completed the interpersonal emotion regulation task involving sadness.Results showed that（1）the cognitive reappraisal strategy could reduce the targets’sadness more effectively;（2）For intrapersonal functional connectivity,the regulators’neural coupling of empathic systems（i.e.supplementary motor cortex）was significantly stronger in the stage of emotion sharing than in other stages.Compared to expressive suppression strategy,cognitive reappraisal enhanced the neural coupling between the empathy system（i.e.angular gyrus,inferior temporal gyrus and temporo-parietal junction）as well as the cognitive control system（i.e.inferior frontal gyrus）for targets.（3）For interpersonal brain synchronization,the neural coupling of cognitive control system（left inferior frontal gyrus of the regulators and right middle temporal gyrus of the targets）was significantly stronger in the expression suppression group than others in the emotion regulation stage,while the cognitive reappraisal group was the opposite.A total of 76 female friends’dyads(M_age=21.85,SD=1.905)participated in Experiment 2.They were randomly assigned to cognitive reappraisal or expressive suppression group and completed the interpersonal emotion regulation task involving anger.Results showed that（1）the cognitive reappraisal strategy could reduce the targets’anger more effectively;（2）For intrapersonal functional connectivity,the regulators’neural coupling in empathy（i.e.supramarginal gyrus）and emotion recognition-related（i.e.somatosensory cortex）brain areas during the emotion sharing stage was stronger in the cognitive reappraisal group than in the expressive suppression group.Compared to the expressive suppression group,The targets’neural coupling in the dorsolateral prefrontal cortex of cognitive reappraisal group was stronger than those in expression suppression group,while in the inferior frontal gyrus was weaker than those in the expression suppression group.（3）For interpersonal brain synchronization,the neural coupling of the motor and sensory processing related brain regions（the right premotor cortex of the regulators and the left somatosensory cortex of the targets）was significantly stronger in the expression suppression group than others in the emotion regulation stage,while the cognitive reappraisal group was the opposite.In summary,this study draws the following conclusions:（1）Interpersonal emotion regulation can effectively reduce the targets’negative emotions of the regulated,and the cognitive reappraisal strategy is more effective than expressive suppression.（2）When sadness was down-regulated,the targets’neural coupling in the brain areas related to empathy and cognitive control was stronger in the cognitive reappraisal group than those in the expression suppression group,because the regulators in the cognitive reappraisal group needed more cognitive empathy,language comprehension,mentalization and other cognitive processes to understand and use the strategies described by the regulators.（3）When anger was down-regulated,the targets’neural coupling in the dorsolateral prefrontal cortex and superior temporal gyrus was stronger in the cognitive reappraisal group than those in the expression suppression group,while the targets’neural coupling in the inferior frontal gyrus and superior temporal gyrus was weaker in the cognitive reappraisal group than those in the expression suppression group.Because cognitive reappraisal requires a top-down reinterpretation to emotional stimuli,which is related to the activity of dorsolateral prefrontal cortex,expression suppression is a goal-driven response suppression process,which is related to the activity of inferior frontal gyrus.（4）Regardless of down-regulating sadness or anger,in the emotion regulation stage,the interpersonal brain synchronization of cognitive control system was significantly weaker in the cognitive reappraisal group than those in the expression suppression group,because the inferior frontal gyrus,as a key brain region in cognitive control and attention control,was highly activated in the process of self-behavioral suppression and emotional suppression.This study found that the inferior frontal gyrus is also involved in suppressing others’emotional expression in social interaction.