Multilevel Resting-State Dysfunctional Connectivity in People With Autism Spectrum Disorder: A Systematic Review and Meta-Analysis.

This large study combined results from 26 previous brain imaging studies to understand how the brains of autistic people connect and communicate differently. The researchers found that autistic people have weaker connections in two important brain networks: one involved in attention and another involved in self-reflection and social thinking. These differences were consistent across multiple studies and may help explain some autism characteristics.

This systematic review and meta-analysis examined brain connectivity differences in autism spectrum disorder (ASD) using resting-state functional connectivity (rsFC) data from 26 studies comprising 709 people with ASD and 705 controls. The analysis identified significant dysfunction in two key brain networks: the default mode network (DMN) and ventral attention network (VAN). Specifically, individuals with ASD showed reduced connectivity in the right medial cingulate gyrus of the VAN (effect size g = -0.51) and the medial left superior frontal gyrus of the DMN (effect size g = -0.42). This research provides the first meta-analytic evidence for VAN dysfunction in ASD, complementing established findings of DMN abnormalities.

These findings suggest that attention and social-cognitive difficulties in autism may stem from specific brain network connectivity differences. This could inform targeted interventions focusing on attention training and social cognition, and may guide future research into biomarkers for autism diagnosis and treatment monitoring.

Specific limitations are not detailed in the abstract. As with most neuroimaging meta-analyses, potential limitations may include heterogeneity in study methodologies, participant characteristics, and scanning parameters across the included studies.

Autism spectrum disorder (ASD) has been linked to dysfunctional communication among brain regions and functional networks, as reflected by abnormal resting-state functional connectivity (rsFC). However, the consistent findings thus far have been elusive. To examine whether individuals with ASD show rsFC differently than healthy individuals at multiple seed levels, we performed a systematic analysis and meta-analysis at all prior seeds, functional network seeds, and single seed levels. This study was registered in the PROSPERO (registration number CRD42024559418).

Publications were identified in PubMed, Embase, and PsycINFO from database inception until December 20, 2023. Publications were included that provided seed-based whole-brain rsFC contrasts between a sample with ASD and controls at rest. Seed and peak effect coordinates and intergroup effects were extracted for analysis. Random-effects meta-analysis was performed using the Seed-based d Mapping software.

This study included 26 studies from 709 people with ASD and 705 controls. The frontal regions, right medial cingulate gyrus (MCG) (g = -0.51; 95% CI, -0.69 to -0.33) of the ventral attention network (VAN), and medial left superior frontal gyrus (g = -0.42; 95% CI, -0.60 to -0.24) of the DMN were the most robust peak clusters at all prior seeds, functional network seeds, and medial prefrontal cortex seed level respectively. The findings not only support DMN dysfunction in people with ASD but also provide the first evidence of meta-analysis to suggest VAN dysfunction in individuals with ASD.