1. Joshi G, Arnold Anteraper S, Patil K, Semwal M, Goldin R, Furtak S, Chai XJ, Saygin Z, Gabrieli JD, Biederman J, Whitfield-Gabrieli S. {{Integration and Segregation of Default Mode Network Resting-state Functional Connectivity in Transition-age Males with High-functioning Autism Spectrum Disorder: A Proof of Concept Study}}. {Brain Connect}. 2017.
OBJECTIVES: To assess the resting-state functional connectivity (RsFc) profile of the default mode network (DMN) in transition-age males with autism spectrum disorder (ASD). METHODS: Resting-state blood oxygen level dependent functional MRI (fMRI) data were acquired from adolescent and young adult males with high-functioning ASD (N=15) and from age-, sex-, and IQ-matched healthy controls (HC; N=16). The DMN was examined by assessing the positive and negative RsFc correlations of an average of the literature-based conceptualized major DMN nodes (medial prefrontal cortex [mPFC], posterior cingulate cortex, bilateral angular and inferior temporal gyrii regions). RsFc data analysis was performed using a seed driven approach. RESULTS: ASD was characterized by an altered pattern of RsFc in the DMN. The ASD group exhibited a weaker pattern of intra- and extra- DMN positive and negative RsFc correlations respectively. In ASD the strength of intra-DMN coupling was significantly reduced with the mPFC and the bilateral angular gyrii regions. In addition, the polarity of the extra-DMN correlation with the right hemispheric task-positive regions of fusiform gyrus and supramarginal gyrus was reversed from typically negative to positive in the ASD group. A wide variability was observed in the presentation of the RsFc profile of the DMN in both HC and ASD groups that revealed a distinct pattern of sub-grouping using pattern recognition analyses. CONCLUSIONS: These findings imply that the functional architecture profile of the DMN is altered in ASD with weaker than expected integration and segregation of the DMN RsFc. Future studies with larger sample sizes are warranted. Key Words: autism spectrum disorder, resting-state fMRI, default mode network.
