Regional homogeneity changes for treatment response in recurrent major depressive disorder-, a resting state fMRI self case control study

Objective This study was to explore the characteristic of the brain regional homogeneity ( Re-Ho) changes of patients with recurrent major depressive disorders ( MDDs) for antidepressant treatment response u-sing resting-state functional magnetic resonance imaging ( fMRI) . Methods Resting-state fMRI scans were performed on 12 patients with recurrent MDDs before and after ten weeks of antidepressant treatment. Resting state scans were also acquired under similar conditions in 12 gender-, age-, and education-matched healthy controls. Results Compared to healthy controls, the untreated depressed group showed significantly increased regional homogeneity in the right inferior frontal gyrus( BA44) , the right posterior cingulate gyrus( BA31) , the left lentiform nucleus, the right caudate nucleus, the right insula(BA13) ; the treated depressed group showed significantly decreased in the right parahippocampal gyrus, the right superior temporal gyrus. Compared to untreated depressed group, the treated depressed group showed significantly decreased regional homogeneity in the left superior frontal gyrus(BA10) , the bilateral middle frontal gyrus( BA10, BA11 ) , the right inferior frontal gyrus( BA44) , the right dorsal anterior cingulate gyrus ( BA32) and the left parahippocampal gyrus ( BA36). Conclusions The present study provided a further support for a dysfunction in cortical-limbic-basal ganglia circuitry in depression, which is at least partly reversed after antidepressant treatment. Key words: Depressive Disorder; Magnetic Resonance Imaging; Resting state; Regional homogeneity