Abstract / Summary
Background: Social Anxiety Disorder (SAD) is a prevalent mental disorder characterized by altered processing of social stimuli. Intolerance of Uncertainty (IU) has been linked to social anxiety and influences the perception of social information. Yet, the neural correlates of IU in SAD during the processing of emotional stimuli remain insufficiently understood. Methods: In this study, fMRI data were collected from 25 individuals with SAD and 25 healthy controls (HC), who completed a face processing task. Differential associations between the IU subdimensions prospective IU , inhibitory IU , and burden due to IU, brain activity, and functional connectivity were analyzed using full-factorial models. Functional connectivity measures focused on the insula. Results: For prospective IU , analysis of functional activity revealed an interaction effect in parietal regions and the insula ( p TFCE- FWE ≤ 0.031), driven by a positive association between IU and activation in the HC group. Concurrently, prospective IU was negatively associated with insular functional connectivity across both groups ( p TFCE-FWE ≤ 0.031), suggesting reduced insular integration independent of diagnosis. A distinct pattern emerged for burden due to IU , showing a negative association with precuneus and posterior cingulate gyrus functional activity across both groups ( p TFCE-FWE = 0.014). No significant effects were found for inhibitory IU . Conclusions: These findings indicate both disorder-specific and shared neural associations of IU. In particular, prospective IU may hold clinical relevance in SAD, as it is linked to reduced insular connectivity across groups but to increased neural activity exclusively in HC, possibly pointing toward neural vulnerabilities that could inform future approaches to the diagnosis and treatment of SAD.