Abstract
BACKGROUND: Suicide constitutes the second leading cause of death among adolescents globally and represents a critical public health concern. The neural mechanisms underlying suicidal behavior in adolescents with major depressive disorder (MDD) remain poorly understood. Aberrant resting-state functional connectivity (rsFC) in the amygdala, a key region implicated in emotional regulation and threat detection, is strongly implicated in depression and suicidal behavior. AIM: To investigate rsFC alterations between amygdala subregions and whole-brain networks in adolescent patients with depression and suicide attempts. METHODS: Resting-state functional magnetic resonance imaging data were acquired from 32 adolescents with MDD and suicide attempts (sMDD) group, 33 adolescents with MDD but without suicide attempts (nsMDD) group, and 34 demographically matched healthy control (HC) group, with the lateral and medial amygdala (MeA) defined as regions of interest. The rsFC patterns of amygdala subregions were compared across the three groups, and associations between aberrant rsFC values and clinical symptom severity scores were examined. RESULTS: Compared with the nsMDD group, the sMDD group exhibited reduced rsFC between the right lateral amygdala (LA) and the right inferior occipital gyrus as well as the left middle occipital gyrus. Compared with the HC group, the abnormal brain regions of rsFC in the sMDD group and nsMDD group involve the parahippocampal gyrus (PHG) and fusiform gyrus. In the sMDD group, right MeA and right temporal pole: Superior temporal gyrus rsFC value negatively correlated with the Rosenberg Self-Esteem Scale scores (r = -0.409, P = 0.025), while left LA and right PHG rsFC value positively correlated with the Adolescent Self-Rating Life Events Checklist interpersonal relationship scores (r = 0.372, P = 0.043). CONCLUSION: Aberrant rsFC changes between amygdala subregions and these brain regions provide novel insights into the underlying neural mechanisms of suicide attempts in adolescents with MDD.