Atrophic Corpus Callosum Associated with Altered Functional Asymmetry in Major Depressive Disorder

Shuhua Ran,1,* Zhiwei Zuo,2,* Chang Li,3 Xuntao Yin,4 Wei Qu,5 Qianying Tang,5 Yao Wang,1 Yanshu Shi,1 Haitao Li1 1Department of Radiology, Southwest Hospital, Army Medical University, Chongqing, People’s Republic of China; 2Department of Radiology, General Hospital of Western Theater Command, Chengdu, People’s Republic of China; 3Department of Radiology, Daping Hospital, Army Medical University, Chongqing, People’s Republic of China; 4Department of Medical Imaging, Guizhou Provincial People’s Hospital, Guizhou, People’s Republic of China; 5Department of Psychology, Southwest Hospital, Army Medical University, Chongqing, People’s Republic of China*These authors contributed equally to this workCorrespondence: Haitao Li Email liihait@163.comPurpose: Impairments in intra- and inter-hemispheric information transfer circuits have been reported in patients with major depressive disorder (MDD). However, the specific anomalous connection (intra- and/or inter-hemispheric) and hemisphere (left and/or right) in which this connection plays a more dominant role in the pathogenic mechanism underlying MDD are still poorly understood.Patients and Methods: Structural magnetic resonance imaging and resting-state functional magnetic resonance imaging were performed in 33 patients with MDD and 33 healthy controls. The intra- and inter-hemispheric functional connectivity (FC) strength in the default mode network areas and volume of the callosal subregions were computed using independent samples t-tests. The partial correlations between the volumes and FCs were also computed.Results: The patients with MDD had smaller volumes in the genu of the corpus callosum than the controls. The intrahemispheric FCs of the bilateral posterior cingulate gyrus, left precuneus, left medial superior frontal gyrus, left medial orbitofrontal gyrus, left angular gyrus and left middle temporal gyrus, and interhemispheric FCs of the bilateral posterior cingulate gyrus in the patients with MDD were lower than those in the controls. Moreover, the ...