Abnormal resting-state functional connectivity in subregions of amygdala in adults and adolescents with major depressive disorder

Abstract

Abstract Background: The atypical symptoms of major depressive disorder (MDD) in adolescents suggest there may be differences in the pathophysiology between adolescents and adults with MDD. There is limited knowledge about the resting-state functional connectivity (rsFC) of amygdala subregions in MDD patients of different age groups, despite amygdala is believed to be critical in the pathophysiology. Methods: In the current study, 65 adolescents (46 with MDD and 19 controls) and 91 adults (35 with MDD and 56 controls) were recruited. A seed-based functional connectivity analysis was performed for each of the amygdala subregions. A 2×2 ANOVA was used to analyze the main effect of age, diagnosis, and their interaction on the rsFC of each subregion. Results: Significant main effect of age was revealed in the rsFC of bilateral centromedial (CM) subregions and right laterobasal (LB) subregion with several brain regions in the limbic system and frontoparietal network. Significant main effect of diagnosis showed MDD patients of different age showed a higher connectivity than controls between the right LB and left middle frontal gyrus (MFG). Conclusions: The rsFC of specific amygdala subregions with brain regions in limbic system and frontoparietal network is affected by age, indicating a distinct amygdala connectivity profile in adolescents. The decreased rsFC between the right LB and the left MFG in both adolescents and adults with MDD could potentially serve as a biomarker for early diagnosis of MDD.