Excessive Functional Coupling With Less Variability Between Salience and Default Mode Networks in Autism Spectrum...

Area of Science:

• Neuroscience
• Developmental Neuroscience
• Cognitive Neuroscience

Background:

• Atypical activity in the salience network (SN) and default mode network (DMN) is documented in autism spectrum disorder (ASD).
• The interaction dynamics between the SN and DMN in ASD remain unexplored.

Purpose of the Study:

• To characterize the functional connectivity and its dynamics between the SN and DMN in individuals with ASD.
• To compare SN-DMN interactions in ASD versus typically developing individuals using resting-state fMRI.

Main Methods:

• Utilized resting-state fMRI data from the Autism Brain Imaging Data Exchange (ABIDE) dataset.
• Included 325 individuals with ASD and 356 typically developing controls.
• Examined static and dynamic functional connectivity using the medial prefrontal cortex (mPFC) as a DMN seed.

Main Results:

• Individuals with ASD exhibited significantly higher mPFC-insula (SN core) connectivity compared to controls.
• The mPFC-insula coupling in ASD showed reduced variability.
• Stronger mPFC-insula coupling in ASD was linked to reduced spontaneous attentional shifts and social responsiveness.

Conclusions:

• Findings suggest excessive coupling between the DMN and SN contributes to internally oriented cognition in ASD.
• Altered SN-DMN interaction dynamics may underlie core features of autism spectrum disorder.