Journal Article

Abnormal functional connectivity of default mode sub-networks in autism spectrum disorder patients

O'Boyle, Jacqueline G., Jagannathan, Kanchana, Assaf, Michal, Pearlson, Godfrey D., Stevens, Michael C., Schultz, Robert T., Calhoun, Vince D., Miller, Laura, Sahl, Robert

2010

Overview

Autism spectrum disorders (ASDs) are characterized by deficits in social and communication processes. Recent data suggest that altered functional connectivity (FC), i.e. synchronous brain activity, might contribute to these deficits. Of specific interest is the FC integrity of the default mode network (DMN), a network active during passive resting states and cognitive processes related to social deficits seen in ASD, e.g. Theory of Mind. We investigated the role of altered FC of default mode sub-networks (DM-SNs) in 16 patients with high-functioning ASD compared to 16 matched healthy controls of short resting fMRI scans using independent component analysis (ICA). ICA is a multivariate data-driven approach that identifies temporally coherent networks, providing a natural measure of FC. Results show that compared to controls, patients showed decreased FC between the precuneus and medial prefrontal cortex/anterior cingulate cortex, DMN core areas, and other DM-SNs areas. FC magnitude in these regions inversely correlated with the severity of patients' social and communication deficits as measured by the Autism Diagnostic Observational Schedule and the Social Responsiveness Scale. Importantly, supplemental analyses suggest that these results were independent of treatment status. These results support the hypothesis that DM-SNs under-connectivity contributes to the core deficits seen in ASD. Moreover, these data provide further support for the use of data-driven analysis with resting-state data for illuminating neural systems that differ between groups. This approach seems especially well suited for populations where compliance with and performance of active tasks might be a challenge, as it requires minimal cooperation. ► Three default mode sub-networks (DM-SNs) were identified from resting state fMRI scans of 16 patients with high-functioning autism spectrum disorders (ASD) and 16 matched healthy controls (HC) using independent component analysis (ICA). ► Compared to HC, patients with ASD showed decreased functional connectivity between the precuneus and medial prefrontal cortex/anterior cingulate cortex and other DM-SNs areas. ► FC magnitude in these regions inversely correlated with the severity of patients’ social and communication deficits as measured by the Autism Diagnostic Observational Schedule and the Social Responsiveness Scale. ► Supplemental analyses suggest that these results were independent of treatment status.

• Publisher: Elsevier Inc,Elsevier Limited
• Subject: Adolescent / Autism / Behavior / Brain / Brain - physiopathology / Brain research / Child / Child Development Disorders, Pervasive - physiopathology / Cognition & reasoning / Default mode network / Female / Functional MRI / High-functioning autism / Humans / Image Interpretation, Computer-Assisted - methods / Independent component analysis / Magnetic Resonance Imaging - methods / Male / Nerve Net - abnormalities / Nerve Net - physiopathology / Neural networks / Neural Pathways - abnormalities / Neural Pathways - physiopathology / Patients / Reproducibility of Results / Resting state / Sensitivity and Specificity / Young Adult