1Key Laboratory of Cognition and Personality (SWU), Ministry of Education, Chongqing 400715, China
2Department of Psychology, Southwest University, Chongqing 400715, China
3Institute of Neuroscience, Chongqing Medical University, Chongqing 400016, China
4Chongqing Key Laboratory of Neurobiology, Chongqing 400016, China
5Department of Neurology, First Affiliated Hospital, Chongqing Medical University, Chongqing 400016, China

Abstract 

In this study, we investigated the role of structural asymmetry of the dorsolateral prefrontal cortex (DLPFC) in the continuum of depression from healthy individuals to patients. Structural magnetic resonance imaging was performed in 70 patients with major depressive disorder (MDD), 49 matched controls, and 349 healthy university students to calculate structural asymmetry indexes of the DLPFC. First-episode, treatment-naive MDD patients showed a relatively lower asymmetry index than healthy controls, and their asymmetry index was negatively correlated with the depressive symptoms. This abnormality was normalized by antidepressants in medicated MDD patients. Furthermore, the asymmetry index was negatively correlated with the depressive symptoms in university students; this was replicated at two time points in a subgroup of students, suggesting good test–retest reliability. Our findings are consistent with previous studies that support the imbalance hypothesis of MDD and suggest a potential structural basis underlying the functional asymmetry of the DLPFC in depression. In future, the structural index of the DLPFC may become a potential biomarker to evaluate individuals’ risk for the onset of MDD.

Keywords

Major depressive disorder, Structural magnetic resonance imaging, Dorsolateral prefrontal cortex, Structural asymmetry

[SpringerLink]