Neural Sensitivity to Conversational Inter-Speaker Gaps in the Broad Autism Phenotype

Pragmatic language differences are present in the broad autism phenotype (BAP). Objective markers of pragmatic language subprocesses, such as inter-speaker turn-taking, may enhance understanding of these differences. Here, we examined how neural and behavioral responses elicited by inter-speaker turn-taking are related to the BAP, using well-validated conversational stimuli with different inter-speaker gap durations in a stratified sample of 63 adults selected for varied autism-associated traits. As outcomes, we measured ERPs elicited by inter-speaker gap (stimulus-preceding negativity) and speaker response (P3), and subjective ratings of conversation quality. Among individuals with more autism-associated traits, extended inter-speaker gaps were considered less salient as indicated by reduced P3. However, monitoring of inter-speaker gaps and perceived conversation quality were unrelated to autism-associated traits. These findings provide preliminary evidence that pragmatic inference of inter-speaker gaps may be specifically disrupted in those endorsing a higher degree of autism-associated traits and detectable with the P3 ERP, laying the foundation for similar neurobehavioral studies in autism.