Interhemispheric functional connectivity in untreated first-episode major depressive disorder: a resting-state functional magnetic resonance imaging study

Abstract

Objective To investigate functional connectivity between the two hemispheres in major depressive disorder using voxel-mirrored homotopic connectivity (VMHC) based on resting-state functional magnetic resonance imaging (rs-fMRI). Methods Thirty patients with unmedicated major depressive disorder and 70 normal controls underwent the rs-fMRI. The whole brain VMHC was calculated and correlation analysis was performed between the regional VMHC and HAMD scores. Results The major depressive disorder patients showed lower VMHC than normal controls in the cerebellum posterior lobe (t=-3.74), and fusiform/lingual gyrus (t=-3.29). There were no significant correlations between the VMHC values in these regions and HAMD scores (r=- 0.16, P=0.451; r=- 0.22, P=0.295). Conclusion The functional coordination between homotopic brain regions be impaired in major depressive disorder. Key words: Depressive disorder; Magnetic resonance imaging; Brain function; Voxel-mirrored homotopic connectivity