Connectivity alterations in autism reflect functional idiosyncrasy.

Area of Science:

• Neuroscience
• Developmental Neuroscience
• Computational Neuroscience

Background:

• Autism spectrum disorder (ASD) is often viewed as altered brain networks, but case-control studies show inconsistent results.
• Understanding inter-individual variability in brain functional organization is crucial for explaining these inconsistencies.

Purpose of the Study:

• To develop a novel approach to profile inter-individual variability in functional brain network organization.
• To investigate if this functional idiosyncrasy contributes to connectivity alterations in ASD.
• To explore the relationship between functional idiosyncrasy, age, symptom severity, and genetic factors in ASD.

Main Methods:

• Utilized a multi-centric dataset comprising 157 individuals with ASD and 172 typically developing (TD) individuals.
• Applied a novel approach to quantify inter-individual variability in functional network organization.
• Correlated functional idiosyncrasy with age, ASD symptom severity, cortical thickness, and ASD risk gene expression patterns.

Main Results:

• Found significantly increased functional idiosyncrasy in ASD within default mode, somatomotor, and attention networks, and reduced idiosyncrasy in lateral temporal cortices.
• Observed that functional idiosyncrasy increases with age and correlates with ASD symptom severity.
• Demonstrated that patterns of atypical idiosyncrasy in ASD overlap with conventional connectivity alterations, potentially explaining inconsistencies in prior research.

Conclusions:

• Inter-individual functional brain network idiosyncrasy is a key feature of autism spectrum disorder.
• Functional idiosyncrasy patterns in ASD are linked to ASD risk gene expression and may drive observed connectivity anomalies.
• This approach offers novel biomarkers for studying atypical brain development and reconciling variable findings in autism connectomics.