Shared functional abnormalities within somatosensory cortex in obsessive-compulsive disorder and anxiety disorders: A comparative meta-analysis.

BACKGROUNDS: Obsessive-compulsive disorder (OCD) has been consistently associated with alterations in cortico-striato-thalamo-cortical (CSTC) circuits, as demonstrated by numerous resting-state fMRI studies. However, given the high prevalence of comorbid anxiety disorders and anxiety-related traits in OCD patients, previous research has not clearly established whether these neural alterations are specific to OCD or represent shared pathophysiology with anxiety disorders (ANX).

METHODS

We conducted a coordinate-based meta-analysis using Signed Differential Mapping (SDM) of whole-brain resting-state fMRI studies in OCD (n = 1429 patients, n = 1509 healthy controls). To assess whether identified alterations were OCD-specific or shared with anxiety pathophysiology, we performed comparative meta-analyses including 15 ANX studies (n = 558 patients, n = 561 healthy controls) using conjunction and contrast analyses, and examined resting-state local brain activity as indexed by ALFF, fALFF, and ReHo.

RESULTS

Compared to ANX, OCD patients showed increased spontaneous activity in the left anterior cingulate cortex extending to the medial prefrontal cortex (ACC/MPFC), right globus pallidus, and left putamen, alongside decreased spontaneous activity in the left middle frontal gyrus. Both disorders shared decreased spontaneous activity in the left postcentral gyrus. However, this meta-analysis did not identify significant differences in amygdala activity in within-group or between-group comparisons, nor in conjunction analyses.

CONCLUSIONS

Overall, this meta-analysis reveals shared reductions in spontaneous activity in the left postcentral gyrus across OCD and ANX, suggesting a potential role for the somatosensory cortex in transdiagnostic emotional processing.