Insula-Retrosplenial Cortex Overconnectivity Increases Internalizing via Reduced Insight in Autism

Area of Science:

• Neuroscience
• Psychiatry
• Developmental Psychology

Background:

• Internalizing symptoms, such as anxiety and depression, are prevalent and debilitating in autism spectrum disorder (ASD).
• Aberrant functional connectivity within and between key brain networks is hypothesized to underlie internalizing symptoms in ASD.

Purpose of the Study:

• To investigate the association between resting-state functional connectivity and internalizing symptoms in adolescents and young adults with ASD.
• To test the hypothesis that altered connectivity among the salience network (SN), default mode network (DMN), and frontoparietal network (FPN) contributes to internalizing psychopathology in ASD.

Main Methods:

• Examined resting-state functional connectivity in 102 adolescents and young adults (49 with ASD, 53 typically developing).
• Utilized seed-to-target functional connectivity analysis with a human cerebral cortex parcellation.
• Analyzed aberrant connections in ASD dimensionally against parent-reported internalizing symptoms.

Main Results:

• Found significant overconnectivity in ASD within three connections: SN-DMN (anterior insula-retrosplenial cortex), SN-FPN (anterior insula-frontal pole), and FPN-DMN (dorsolateral prefrontal cortex-retrosplenial cortex).
• The SN-DMN overconnectivity was specifically associated with increased internalizing symptoms in ASD, mediated by discrepancies in self- and parent-reported symptom severity.
• Control analyses confirmed the specificity of the SN-DMN finding to internalizing symptoms and not externalizing symptoms.

Conclusions:

• Novel evidence supports a specific link between SN-DMN overconnectivity and internalizing symptoms in ASD.
• Intact anterior insula-retrosplenial connectivity may be crucial for self-insight into one's own psychopathology in ASD.