Inflexible Updating of the Self-Other Divide During a Social Context in Autism: Psychophysical, Electrophysiological, and Neural Network Modeling Evidence.

This study looked at how people with autism process personal space boundaries around their body. When neurotypical people are around others, they automatically adjust their sense of personal space, but people with autism don't show this same flexibility. Brain wave recordings and computer modeling suggested this difference may be due to how the autistic brain processes sensory information and maintains balance between brain activity. This inflexibility in adjusting personal boundaries may contribute to social challenges in autism.

This study investigated peripersonal space (PPS) - the boundary between self and others - in autism using behavioral, electrophysiological, and neural modeling approaches. Fifty young adults (20 with ASD, 30 neurotypical) completed a visuotactile reaction time task while EEG was recorded. Results showed that neurotypical individuals automatically adjust their personal space boundary when others are present, but autistic individuals do not show this flexible updating. EEG findings suggested altered multisensory integration patterns in autism.

Neural network modeling indicated that excitatory/inhibitory imbalances characteristic of autism may underlie this inflexibility. The findings support theories of reduced flexibility in autism and provide neurobiological insights into social boundary processing differences.

Results suggest that difficulties with social boundaries in autism may stem from reduced flexibility in sensory-social processing rather than social motivation deficits. This could inform therapeutic approaches focusing on sensory integration and environmental adaptations to support social functioning.

Single study with moderate sample size. Neural network modeling provides theoretical proof-of-principle rather than direct evidence. Cross-sectional design limits causal inferences. Unclear if findings generalize to real-world social situations or different age groups.

Autism spectrum disorder (ASD) affects many aspects of life, from social interactions to (multi)sensory processing. Similarly, the condition expresses at a variety of levels of description, from genetics to neural circuits and interpersonal behavior. We attempt to bridge between domains and levels of description by detailing the behavioral, electrophysiological, and putative neural network basis of peripersonal space (PPS) updating in ASD during a social context, given that the encoding of this space relies on appropriate multisensory integration, is malleable by social context, and is thought to delineate the boundary between the self and others. Fifty (20 male/30 female) young adults, either diagnosed with ASD or age- and sex-matched individuals, took part in a visuotactile reaction time task indexing PPS, while high-density electroencephalography was continuously recorded.

Neural network modeling was performed in silico. Multisensory psychophysics demonstrates that while PPS in neurotypical individuals shrinks in the presence of others-as to "give space"-this does not occur in ASD. Likewise, electroencephalography recordings suggest that multisensory integration is altered by social context in neurotypical individuals but not in individuals with ASD. Finally, a biologically plausible neural network model shows, as a proof of principle, that PPS updating may be inflexible in ASD owing to the altered excitatory/inhibitory balance that characterizes neural circuits in animal models of ASD.

Findings are conceptually in line with recent statistical inference accounts, suggesting diminished flexibility in ASD, and further these observations by suggesting within an example relevant for social cognition that such inflexibility may be due to excitatory/inhibitory imbalances.