The Functional Dysconnectivity Within the Emotion Regulation System Is Associated with Anhedonia in Major Depressive Disorder

Abstract

Objective: The neuro-pathphysiological abnormalities of Major Depressive Disorder (MDD) have been reported to be distributed in emotion regulation system, involving the prefrontal cortex, limbic and subcortical nuclei[8]. Anhedonia is recognized as a hallmark of MDD. Characterizing the aberrant functional connectivity (FC) within this system and exploring the relationships between these dysconnectivity and anhedonia will help us better look into the neuro-pathophysiological mechanisms underlying MDD. Methods: Sixty-three MDD and 63 healthy controls (HCs) underwent resting-state functional magnetic resonance imaging (rsfMRI). The spatial pairwise clustering (SPC) analysis and network-based statistic (NBS) were used to explore the alterations in the emotion regulation system of MDD from voxel level to network level. The alterations in FC and their relationships with anhedonia symptom were explored. Result: This study suggested that the aberrant FC subnetworks within the emotion regulation system mainly involved in prefrontal-limbic system, prefrontal-striatum system and within the limbic system. In addition, the aberrant subnetworks of prefrontal cortex/anterior cingulate cortex and amygdala/hippocampus could predict the anhedonia symptom in MDD. Conclusion: These findings demonstrated that MDD showed characteristic pathological alterations of the emotion regulation system. Moreover, the abnormal FC between the prefrontal cortex/anterior cingulate cortex and the amygdala/hippocampus might be the potential neural markers of depression-related anhedonia.