Judgments of spoken discourse and impression formation of neurotypical and autistic adults

Background: Studies on impression formation in Autism Spectrum Disorder (ASD) have suggested that both ASD and neurotypical (NT) individuals extract paralinguistic cues (e.g., vocal and facial expressions) from brief extracts of social behaviors to form less favorable impressions of the personality traits of ASD individuals than of their NT peers. Yet, discourse studies in ASD have also suggested that there are specific linguistic features (e.g., conjunctions) that can distinguish the speech of ASD individuals from that of NT individuals. This study investigates whether naive participants with and without autism can perceive discourse features previously identified as characteristic of ASD speech, based on a single exposure to conversation extracts. Methods: A cross-design rating experiment was created whereby a group of ASD and NT adults (blind to diagnosis information) rated audio recordings involving ASD and NT speakers. Rating participants evaluated the recordings using a Likert scale targeting impressions of discourse features. Results: ASD and NT Raters behaved similarly on the ratings of discourse features; evaluating the speech of ASD Speakers less favorably than those of NT Speakers. Conclusion: Our results extend previous findings by showing that linguistic cues also lead to less favorable impressions of the discourse of ASD Speakers, and this from both the perspective of NT and ASD Raters.