Prosodic marking of contrastive focus in Mandarin-speaking children with autism spectrum disorder.

Introduction: Prosodic focus marking plays a central role in conveying information structure, yet little is known about how Mandarin-speaking children with autism spectrum disorder (ASD) use acoustic cues to signal contrastive focus in a tonal language. Methods: Prosodic focus marking plays a central role in conveying information structure, yet little is known about how Mandarin-speaking children with autism spectrum disorder (ASD) use acoustic cues to signal contrastive focus in a tonal language. This study examined pitch, duration, and intensity in sentence-initial and sentence-final focus produced by 20 Mandarin-speaking children with ASD and 20 age- and sex-matched typically developing (TD) peers. Using picture-based prompts, children produced simple subject-verb-object sentences, and acoustic measures of focus words (sentence-initial subject and sentence-final object) and post-focus verbs were analyzed with linear mixed-effects models. Results: Children with ASD showed significantly higher pitch than TD children in sentence-final focus, with no group difference in sentence-initial focus. Duration ratio was significantly reduced only with high-tone verbs. Intensity ratio was lower in sentence-initial focus, but higher in sentence-final focus with high-tone verbs. In the post-focus region, children with ASD exhibited higher pitch than TD children for both high- and low-tone verbs, but showed larger duration ratio and lower intensity ratio only for low-tone verbs. Discussion: These findings suggest that children with ASD are not globally impaired in focus marking, but show patterns that vary with focus position and tonal context.