Neural correlates of rumination and social anxiety: Mediating role of vmPFC connectivity in resting-state fMRI.

Rumination is closely associated with social anxiety and is considered a key cognitive factor in its onset and persistence. Both processes engage brain functions related to self-referential cognition and emotional regulation; however, the neural pathways linking rumination and social anxiety remain incompletely understood. Using resting-state neuroimaging data from 470 participants, we conducted voxel-based functional connectivity analysis focusing on the ventromedial prefrontal cortex (vmPFC), a key region implicated in self-referential processing and affective regulation. Results showed that functional connectivity between the anterior vmPFC and the left inferior frontal gyrus (IFG) and the right superior frontal gyrus (SFG) was significantly associated with both rumination and social anxiety, and mediated their association. Notably, functional connectivity related to social anxiety was primarily observed in the anterior rather than the posterior vmPFC, suggesting that social anxiety may be closely linked to heightened sensitivity to social value and reward cues. This study reveals the central role of the vmPFC in integrating self-related cognition and emotion regulation, demonstrating how its functional connectivity mediates the influence of rumination on social anxiety, thereby deepening our understanding of the neural mechanisms underlying social anxiety.