Atypical Intrinsic Hemispheric Interaction Associated with Autism Spectrum Disorder Is Present within the First Year...

Area of Science:

• Neuroscience
• Developmental Psychology
• Genetics

Background:

• Autism spectrum disorder (ASD) is associated with atypical functional network connectivity lateralization.
• Previous research has not clarified the onset timing of these network differences in infancy.
• Understanding early brain development is crucial for identifying potential biomarkers for ASD.

Purpose of the Study:

• To investigate hemispheric asymmetries of functional brain network connectivity in infants and children with ASD.
• To determine if atypical network lateralization is present in early infancy in individuals later diagnosed with ASD or at high risk.
• To examine the developmental trajectory of these connectivity differences from 1 to 9 months of age.

Main Methods:

• Analyzed functional connectivity data from 733 children (ASD vs. typically developing) and 71 infants (high-risk vs. normal-risk) at 1 and 9 months.
• Focused on specific brain regions including the posterior cingulate cortex (PCC), posterior superior temporal gyrus, extrastriate cortex, and anterior prefrontal cortex.
• Compared connectivity patterns between groups and assessed correlations with symptom severity.

Main Results:

• In children, significant group differences in connectivity were found in four brain regions.
• No significant group differences in connectivity asymmetries were observed at 1 month of age.
• By 9 months, atypical connectivity was evident in the PCC and extrastriate cortex in infants at high risk for ASD compared to normal-risk infants.

Conclusions:

• Atypical network asymmetries associated with ASD risk are detectable before a reliable clinical diagnosis.
• These findings suggest that early brain development trajectories may differ in infants at high risk for ASD.
• Early identification of network differences could inform future diagnostic and intervention strategies.