RÉSUMÉ
Objective To explore the functional connectivity characteristics and intensity of brain network in depression at rest.Methods Patients with major depressive disorder(MDD)and healthy controls(HCs)underwent resting state functional magnetic resonance imaging.The total brain degree centrality(DC)of the two groups was calculated to assess the functional connection strength.Support vector machine(SVM)method was used to investigate whether abnormal DC value can recognize MDD.Results A total of 26 patients and 37 controls were included in the analysis.Compared to HCs,MDD group showed decreased DC value in the left middle frontal gyrus(t=-4.98,P＜0.05,GRF corrected)and increased DC value in the right middle temporal gyrus(t=5.02,P＜0.05,GRF corrected),right parahippocampal gyrus(t=4.80,P＜0.05,GRF corrected),and right posterior cerebellar gyrus(t=4.98,P＜0.05,GRF corrected).Additionally,no significant correlations were found between abnormal DC values and clinical variables(i.e.,17-item Hamilton depression scale and Beck depression scale scores)in MDD group(P＞0.05).SVM analysis showed that decreased DC value in the left middle frontal gyrus might be used to distinguish MDD group from HCs with an accuracy of 84.13%,a specificity of 81.08%,and a sensitivity of 88.46%,the area under the operational characteristic curve is 0.87.Conclusions Altered DC values in the left middle frontal gyrus and right middle temporal gyrus,right parahippocampal gyrus,right posterior cerebellum may contribute to the pathophysiology of MDD.The change of functional connection strength of the left medial frontal gyrus may be helpful for the recognition of MDD.