Study Of Transcranial Direct Current Stimulation Therapy For Major Depressive Disorder On Anticipatory Anhedonia

Objective: Major depressive disorder(MDD)is a psychological disorder with persistent depression and anhedonia as the core symptoms.Many fields in MDD will appear different degree of damage.In numerous studies,anhedonia in MDD patients is rarely studied,indicating poor response to treatment and low remission rate.Compared to healthy people,anticipatory anhedonia in MDD is more damaging.Transcranial direct current stimulation(tDCS)is a noninvasive technique that using small current to enhance or inhibit cortical stimulation.It has shown therapeutic potential in a range of neuropsychiatric disorders,including MDD.But the mechanism of treatment is unclear.In this study,to observe the therapeutic effect of anticipatory anhedonia in MDD patients with the help of symptom scale and behavioral evaluation,tDCS was used to intervene MDD patients with orbitofrontal cortex(OFC)as the therapeutic target.Methods: Patients were screened by the Temporal Experience of Pleasure Scale(TEPS),37 patients with MDD were randomly assigned to real tDCS group(15 cases),sham tDCS group(11 cases)and the control group(11 cases).The real tDCS group was treated with 2m A of tDCS,the sham tDCS group was treated with the same parameter setting.Both groups lasted 14 days,before and after treatment,behavioral evaluation,assessment of clinical symptom scale were performed.The control group was evaluated by clinical symptom scale,behavioral evaluation before and after 14 days.Hamilton Depression Scale(HAMD-17),Beck Depression Inventory(BDI-21)and TEPS were used for the clinical symptom scale.Monetary Incentive Delay paradigm(MID)wasused for behavior evaluation.SPSS 16.0 software were used to analyze the data.The data were statistically analyzed using descriptive statistical analysis,one-way analysis of variance and repeated measurement analysis of variance.Results: Before treatment,there was no significant difference in the accuracy rate and response time of different cues and the scores of clinical symptom scales among the three groups(P>0.05).The baseline was stable.After treatment,(1)In symptoms: In the HAMD-17 and BDI-21 score,the group main effect was not significant(F=0.97,P=0.39;F=0.91,P=0.41);the interaction between time and group was significant(F=22.81,P < 0.01;F=3.49,P=0.04).The posttest was significantly lower than the pretest in the real tDCS group(P<0.01);the posttest was significantly lower than the pretest in the sham tDCS group(P<0.01);the posttest was significantly lower than the pretest in the control group(P<0.05).In the TEPS,TEPS-ant and TEPS-con score,the group main effect was not significant(F=0.21,P=0.81;F=0.92,P=0.41;F=0.43,P=0.66);the interaction between time and group was significant(F=9.74,P<0.01;F=11.44,P<0.01;F=4.97,P=0.01).The posttest was significantly higher than the pretest in the real tDCS group(P<0.01);the sham tDCS group had no significant difference before and after(P>0.05);the control group had no significant difference before and after(P>0.05).(2)In behavioral results: In the accuracy of paradigm,the group main effect was not significant(F=0.26,P=0.77),the interaction among cue,time and group was not significant(F=1.46,P=0.21).In each of the three groups,there was no significant difference between the pretest and the posttest in the accuracy of different cue tasks(P> 0.05).In the reaction time of paradigm,the group main effect was not significant(F=0.19,P=0.83),the interaction among cue,time and group was not significant(F=1.52,P=0.18).In each of the three groups,there was no significant difference between the pretest and the posttest in the reaction time of different cue tasks(P>0.05).Conclusion: Transcranial direct current stimulation treatment can improve anticipatory anhedonia in MDD patients.