A preliminary study of functional connectivity of medication naïve children with obsessive-compulsive disorder.

BACKGROUND: Evidence suggests that obsessive-compulsive disorder (OCD) is associated with a dysfunction in the cortico-striatal-thalamic-cortical (CSTC) circuitry. Resting state functional connectivity magnetic resonance imaging (rs-fcMRI) allows measurements of resting state networks (RSNs), brain networks that are present at 'rest'. However, although OCD has a typical onset during childhood or adolescence, only two other studies have performed rs-fcMRI comparisons of RSNs in children and adolescents with OCD against healthy controls.

METHODS: In the present study, we performed resting state functional magnetic resonance imaging using a 3 Tesla MRI, in 11 medication-naïve children and adolescents with OCD and 9 healthy controls. In contrast to previous studies that relied on a priori determination of RSNs, we determined resting state functional connectivity with a data-driven independent component analysis (ICA).

RESULTS: Consistent with previous reports in healthy adults, we identified 13 RSNs. Case-control un-adjusted statistical significance (p<0.05) was found for two networks. Firstly, increased connectivity (OCD>control) in the right section of Brodmann area 43 of the auditory network; Secondly, decreased connectivity in the right section of Brodmann area 8 and Brodmann area 40 in the cingulate network.

CONCLUSIONS: Our preliminary findings of case-control differences in RSNs lend further support to the CSTC hypothesis of OCD, as well as implicating other regions of the brain outside of the CSTC.