A Study Of Interpretation Bias In Patients With Major Depressive Disorder Toward Event-related Potentials

Objective: Major Depressive disorder(MDD)is a common clinical mental disorder,which is characterized by diverse clinical manifestations,unclear mechanism,high misdiagnosis rate,low effective treatment rate,and high recurrence rate.Robust evidence support the idea that interpretation biases are implicated with depression.Furthermore,considerable studies with different stimulation and evaluation methods not only have confirmed the tendency of depressed patients to interpret ambiguous emotional information as negative,but also revealed that the size of interpretation bias might be influenced by a variety of factors.Event-related potentials(ERPs)are widely used to explore the brain’s neural mechanisms for emotional processing because of their high time resolution.The main purpose of this study was to longitudinally a investigate the patterns of EEG responses that correlated with interpretation bias when in face of emotional faces in patients with first episode depression before and after treatment.And the secondary objective is to explore the clinical symptoms associated with interpretation bias.Methods: 41 participants(22 first-episode,medication-naive MDD,and 19 age-,gender-,and education-matched health controls)were recruited into our study.All participants were required to complete the emotional face recognition task,while behavioral data(emotional image recognition accuracy)were collected to verify negative interpretation bias in depressed patients.Late-positive potentials(LPP)was used to explore differences in cognitive emotional processes between MDD and healthy controls when faced with emotional facial expressions.Our study further adopted Pearson correlation and Logistic regression to explore the association between interpretation basis and clinical characteristics in MDD patients.Results: 1)MDD patients showed a tendency to interpret neutral face images as negative compared with healthy people,while no significant group differences were observed in happy or sad emotional faces;There was no significantly statistical difference in the effect of childhood trauma experience rumination style on the recognition of neutral emotional face images.2)When faced with happy and sad pictures,the LPP wave of healthy controls was significantly higher than in the face of neutral face pictures,while the LPP amplitude of depressed patients for neutral image stimulation significantly increased compared to healthy controls.Furthermore,the LPP wave rise was similar to that of depressed patients.The amplitude of LPP induced by happy face images in depressed patients was not significantly different from that in normal people.3)We further found that the increase of LPP stimulated by negative image in depressed patients was positively correlated with the cognitive impairment factor score of HAMD-24,but negatively associated with the score of consummatory anhedonia measured by the Temporal Experience Experience Scale(TEPs-CON).Conclusion: As a sensitive and appropriate technique,ERPs was adopted in our study to explore the neural underpinning of the interpretation bias.Our study revealed that the interpretation bias is highly associated with anhedonia and cognitive impairment.MDD was supposed to be implicated with negative interpretation bias.Furthermore,Distal markers(e.g.,childhood trauma experiences)and clinical symptoms involving in interpretative bias still merit further exploration.