Idiosyncratic brain activation patterns are associated with poor social comprehension in autism

Area of Science:

• Neuroscience
• Psychology
• Medical Imaging

Background:

• Autism spectrum disorder (ASD) is characterized by significant social deficits, yet neuroimaging has not identified a consistent neural basis.
• Previous research has struggled to link brain activity patterns with social impairments in ASD.

Purpose of the Study:

• To investigate the relationship between brain activation patterns during social interaction and social comprehension deficits in individuals with ASD.
• To determine if idiosyncratic brain responses are associated with specific social understanding difficulties in ASD.

Main Methods:

• Functional magnetic resonance imaging (fMRI) was used to record brain activity in participants with ASD (N=17) and controls (N=20) while they watched a sitcom.
• Intersubject correlation analysis was employed to compare patterns of brain activation between groups.
• Neuropsychological assessments and eye-tracking were utilized to explore potential explanatory factors for observed brain activity patterns.

Main Results:

• Reduced intersubject correlations in brain activation were observed in the ASD group.
• This reduction was primarily driven by a subset of five ASD participants exhibiting idiosyncratic and internally unreliable brain responses.
• These five participants showed specific impairments in understanding character motivations, while the remaining ASD participants' brain activity was comparable to controls.

Conclusions:

• Idiosyncratic patterns of brain activation during seminaturalistic social stimuli are linked to social comprehension deficits in a subset of individuals with ASD.
• These findings underscore the heterogeneity of ASD and suggest a specific neurofunctional basis for social understanding difficulties.
• Future research should consider the diverse neural profiles within the ASD population.