The following is a summary of the “Abnormal resting-state functional connectivity of the insula in medication-free patients with obsessive-compulsive disorder” published in the November 2022 issue of Psychiatry by Zhou et al.

Recent neurocircuitry models of obsessive-compulsive disorder (OCD)  have begun to include the insula as a key player due to its extensive interactions with the conventional cortico-striato-thalamo-cortical circuit and its role in affective processing and anxiety regulation. However, little is known about the functional connectivity patterns in the brain during resting states in OCD. Therefore, researchers set out to examine the insula’s intrinsic connectivity and its relationships with clinical characteristics in OCD. In a study with 85 drug-free OCD patients and 85 age- and sex-matched healthy controls (HCs), they analyzed resting-state functional magnetic resonance imaging data. 

Investigators used a general linear model to examine differences in bilateral insula intrinsic functional connectivity between people with OCD and healthy controls. Using Pearson or Spearman correlation analysis, they also looked for a connection between the insula’s intrinsic functional connectivity changes and clinical characteristics. Patients with OCD had enhanced intrinsic connection between the bilateral insula and bilateral precuneus gyrus, extending to the inferior parietal lobule and supplementary motor region, compared to HCs.

Reduced intrinsic connectivity between the right insula and bilateral lingual gyrus in OCD patients compared to HC participants was adversely linked with the degree of depressive symptoms in the OCD group. Here, study group found that OCD patients have reduced insular intrinsic connection, with right insula and bilateral lingual gyrus dysconnectivity being linked to the degree of depression experienced by OCD patients. These results give neuroimaging support for the role for the insula in OCD and imply that it may play a role in the depressed symptoms of OCD.