Approaches to local connectivity in autism using resting state functional connectivity MRI

Area of Science:

• Neuroscience
• Developmental Neuroscience
• Cognitive Neuroscience

Background:

• Autism spectrum disorder (ASD) research has focused on long-distance brain connectivity, with limited understanding of local connectivity patterns.
• Investigating local connectivity is crucial for a comprehensive understanding of neurodevelopmental differences in ASD.

Purpose of the Study:

• To examine local brain connectivity in children and adolescents with ASD compared to typically developing individuals.
• To identify specific patterns of local over- or underconnectivity in different brain regions.

Main Methods:

• Utilized resting-state functional magnetic resonance imaging (fMRI) data from 29 children/adolescents with ASD and 29 matched controls.
• Employed regional homogeneity and local density analyses across multiple spatial scales and analysis pipelines.
• Confirmed findings in low-motion subsamples and with global signal regression.

Main Results:

• Consistent patterns of local overconnectivity were observed in the occipital and posterior temporal regions in the ASD group.
• Underconnectivity was found in the middle/posterior cingulate and medial prefrontal regions in individuals with ASD.
• These findings remained stable across different analysis pipelines and motion-correction strategies.

Conclusions:

• Local overconnectivity in visual regions may support a local visual processing preference in ASD.
• Underconnectivity in cingulate and medial frontal regions could indicate aberrant default mode network function in ASD.
• The study highlights the importance of examining local connectivity for understanding ASD neurobiology.