Connectome-wide functional connectivity abnormalities in youth with obsessive compulsive symptoms.

Abstract Background Obsessive compulsive symptomatology (OCS) is common in adolescence but usually does not meet the diagnostic threshold for obsessive compulsive disorder. Nevertheless, both OCD and subthreshold OCS are associated with increased likelihood of experiencing other serious psychiatric conditions including depression and suicidal ideation. Unfortunately, there is limited information on the neurobiology of OCS. Methods Here we undertook one of the first brain imaging studies of OCS in a large adolescent sample (analyzed n=832) from the Philadelphia Neurodevelopmental Cohort. We investigated resting-state fMRI functional connectivity using complementary analytic approaches that focus on different neuroanatomical scales, from known functional systems to connectome-wide tests. Results We found a robust pattern of connectome-wide, OCS-related differences, as well as evidence of specific abnormalities involving known functional systems, including dorsal and ventral attention, frontoparietal and default mode systems. Analysis of cerebral perfusion imaging and high resolution structural imaging did not show OCS-related differences, consistent with domain specificity to functional connectivity. Conclusions The brain connectomic associations with OCS reported here, together with early studies of its clinical relevance, support the potential for OCS as an early marker of psychiatric risk that may enhance our understanding of mechanisms underlying the onset of adolescent psychopathology.