Functional connectivity of the medial prefrontal cortex and posterior cingulate cortex mediates the association between expressive suppression and rumination in depressed adolescents.

BACKGROUND

Expressive suppression is associated with rumination, but the cortical functional connectivity (FC) patterns characterizing this relationship remain unclear in adolescents with major depressive disorder (MDD). This study examined associations among expressive suppression, rumination dimensions, and cortex-wide resting-state FC.

METHODS

A total of 228 adolescents aged 12-18 years with MDD were included. Expressive suppression and rumination were assessed using questionnaires, and cortex-wide resting-state FC was examined. Partial correlations were performed with covariate adjustment and false discovery rate correction. FC links associated with both expressive suppression and brooding were evaluated in exploratory mediation analyses. Sensitivity models additionally adjusted for anxiety and depressive symptom severity and applied Bonferroni correction across eight indirect effects.

RESULTS

Expressive suppression was positively associated with brooding, reflection, depressive rumination, and overall rumination. Cortex-wide analyses identified FC patterns involving prefrontal, insular, parietal, temporal, and posterior cingulate regions. Two FC links were associated with both expressive suppression and brooding: right medial prefrontal cortex (mPFC)-right posterior cingulate cortex (PCC) FC and right mPFC-left PCC FC. In sensitivity analyses, indirect effects through both FC links remained significant only for brooding after additional symptom adjustment and Bonferroni correction.

CONCLUSIONS

These findings highlight brooding as the rumination dimension most consistently associated with expressive suppression and right mPFC connectivity with the right and left PCC in adolescents with MDD. They may contribute to neurocognitive models of maladaptive self-focused thinking in adolescent depression and inform future longitudinal and intervention research.