Study Of Pain Empathy In Patients With Depression Using Event-related Potential Methods

Objective: Depression is a psychiatric disorder charactered by obvious low mood.It has been demonstrated that patients with depression had impairment in social cognition including theory of mind,face recognition,emotion processing and so on.Empathy is a important abilities for appropriate social communication.It allows us to understand others’ emotion and feelings even though we have not experienced the same situations.To our knowledge,There have been little studies on the ability of empathy in the patients with depression.,In addition,the only existed studies just focus on behavioral study,but the neural mechanism was not clear so far.Hence,in the present study,we use the pain empathy paradigm combining with event-related potentia(ERP)methods to study neural mechanism underlying empathy in depressive patients.Methods:(1)Subjects: 20 patients with depression and 23 healthy controls matched for gender,age and education were recruited.Subjects with impaired vision or brain organic mental disorders orsevere somatopathy or those who were unable to complete the tasks independently were excluded.(2)Empathy questionnaire: Chinese version of Interpersonal Reactivity Index.(3)Pain empathy task: Stimuli were pictures of painful or neural situations as used in previous studies.There were two attention conditions:(1)explicit task:indicate whether or not each picture showed a painful situation;implicit task: subjects were demanded to judge the laterality of hands or feet of that person,and EEG were recorded in the same time.After EEG recording,subjects should to rate the degree of pain according to the person in pictures.Results:(1)Behavioral results: in IRI-C,Patients showed lower scores in factors of fantasy(t=-2.339,P=0.024),higher scores in factors of personal distress(t=2.887,P=0.006).In the behavioral data of pain empathy paradigm,the accuracy showed the interaction effect of the task and group was significant(F(1,43)=6.542,P=0.014)in pain pictures,furthmore,the one-way ANOVA procedure results showed compared to controls,accuracy of painful were significantly lower in patients(F(1,41)=3.437,P=0.071)in explici task,patients and controls were not significantly accuracy in implicit task.In reaction time,patients showed longer react time in all conditions.(2)ERP results: it showed that significant main effect of group in N1 components(F(1,41)=16.396,P<0.001).It showed significant interaction effect between task and groups in P3 components(F(1,41)=6.819,P=0.013).Conclusion: The ability of pain empathy was impaired in patients with depression.