Unraveling neural adaptation to vocal and non-vocal sounds in autism

Objective: Autism is linked to a strong need for sameness and difficulties in social communication, associated with atypical brain responses to voices and changes. This study aimed to characterize neural adaptation in autistic adults using a Roving paradigm and assess how vocal vs. non-vocal, as well as neutral vs. emotional sounds, influence this adaptation.

Methods: Neural adaptation was measured in 20 autistic and 20 non-autistic adults using a Roving paradigm, where sounds were repeated 4, 8, or 14 times. Neural responses and Repetition Positivity (RP) amplitudes were analyzed as indices of adaptation.

Results: RP amplitudes showed no significant differences between groups for vocal or non-vocal sounds, but adaptation dynamics varied. Non-autistic adults adapted more quickly to non-vocal (5-8 repetitions) compared to vocal sounds (12-14 repetitions). In contrast, autistic adults adapt faster to vocal than to non-vocal sounds. Moreover emotional prosodic content influenced RP amplitude in autistic adults only, suggesting heightened sensitivity to emotional cues in social contexts.

Conclusions: The study highlights how atypical neural adaptation in autism how emotional content impacts social communication deficits. These insights enhance understanding of autism-related adaptation challenges.