Self-compassion, self-referential caudate circuitry, and adolescent suicide ideation

Suicide is a leading cause of death in youth, with depression a proximal predictor. Identifying protective psychological factors against suicide ideation in depressed adolescents is critical. Self-compassion is inversely associated with suicide ideation, but underlying neural mechanisms are unclear. Given links between self-referential caudate activity, self-compassion, and suicide ideation, this study tested whether caudate functional connectivity during self-appraisal explains their relationship. Seventy-nine depressed youth and 36 healthy controls, while undergoing fMRI, evaluated whether auditorily presented phrases were self-descriptive from multiple social perspectives. Self-compassion and suicide ideation were assessed via self-report and interview-based measures. Higher self-compassion was associated with stronger left caudate functional connectivity with bilateral posterior superior temporal sulcus/temporoparietal junction (pSTS/TPJ), left middle temporal gyrus (MTG), and left middle occipital gyrus during positive versus negative self-appraisals. Stronger left caudate–left MTG connectivity mediated the association between higher self-compassion and lower suicide ideation, controlling for depression (non-suicidal ideation) severity, anxiety severity, and non-suicidal self-injury. Findings suggest left caudate–MTG connectivity during positive versus negative self-referential processing as a potential biomarker and intervention target to reduce suicide ideation in depressed youth, particularly in conjunction with self-compassion training.