The Study Of Electroconvulsive Therapy Modulating The White Matter Function In Major Depressive Disorder

Background Major Depressive Disorder(MDD)is common worldwide,which has a number of etiological factors and is characterized by persistent mood or emotional distress.Electroconvulsive therapy(ECT)is a rapid and effective treatment for MDD.There are many researches to explore the neural mechanism of MDD,but there is still no unified conclusion.Abnormalities of brain structure and function play an important role in the occurrence and development of depression.Currently,most studies focus on white matter structure,while few studies on the function of white matter.As an aggregation area of fiber bundles,white matter plays an important role in information transmission and can coordinate the normal operation of brain regions.Therefore,the study of white matter function in MDD patients and how ECT regulates the change of white matter function are significant for exploring the neural mechanism of MDD.Objective To understand the alteration of white matter function in patients with MDD is helpful to further deepen the understanding of the neural mechanism of MDD.Explore how ECT modulates the alteration of white matter function can provide more targets for the treatment of MDD.Method We recruited 32 patients with MDD and 46 healthy controls matched with MDD in demographic phase.Resting-state functional Magnetic Resonance Imaging(rsf MRI)scans were performed on all participants of the two groups,and the regional activity of white matter in the two groups was compared by Amplitude of Low Frequency Fluctuation(ALFF).The Hamilton Depression Rating Scale(HDRS)was used to assess the severity of depressive symptoms in both groups.Scanning and clinical evaluation were performed before and after ECT for the MDD group.The ALFF of MDD patients and healthy controls were compared to understand the alteration of white matter function in MDD patients.The alteration in white matter function were further verified by comparing with ALFF after ECT.In addition,we used Spearman correlation analysis to evaluate the correlation between alteration in white matter function and clinical symptom severity(HDRS)in patients with MDD.Results Compared with healthy controls,the amplitude of low frequency fluctuation of the callosum(CC)forceps was reduced in patients with MDD(t=-5.16,p<0.001),while the right corticospinal tract(CST)was enhanced(t = 6.76,p < 0.001).The amplitude of low frequency fluctuation of the right corticospinal tract was improved after ECT(t=-4.89,p<0.001),and the decrease of the amplitude of low frequency fluctuation of the right corticospinal tract was significantly positively correlated with the improvement rate of depressive symptoms in MDD(r = 0.368,p = 0.039).Conclusions Our results suggest that patients with MDD exhibit white matter dysfunction in the corpus callosum forceps and the right corticospinal tract,which can be reversed by ECT.The alteration of white matter function in patients with MDD were correlated with the severity of depressive symptoms.