Fundamental Frequency and Noise Effects on Sentence Recognition in Mandarin-Speaking Autistic Children: The Role of Cognitive Abilities

Purpose: Previous studies have shown that Mandarin-speaking autistic children exhibit atypical pitch processing and their speech perception is easily affected by noise. This study examined how fundamental frequency ( F 0) contour and background noise affect Mandarin sentence recognition in autistic children, and evaluated the roles of verbal intelligence (VIQ), nonverbal intelligence (NVIQ), and working memory (WM) as cognitive predictors. Method: Thirty Mandarin-speaking autistic children and 31 age-matched typically developing (TD) controls completed an open-set sentence recognition task under four conditions: natural F 0 (NF0) versus flat F 0 (FF0) in quiet and in speech-shaped noise at 10 dB SNR. Performance was scored as percent correct monosyllables. VIQ and NVIQ were assessed using the Wechsler Intelligence Scale, and WM was assessed via forward digit span. Results: Both the ASD and TD groups showed reduced accuracy when F 0 contours were flattened and in the presence of noise. The performance of autistic children declined disproportionately under FF0 conditions, whereas they matched TD peers when the F 0 was natural. Noise imposed a similar energetic-masking effect across both groups. Within the ASD group, correlational analyses revealed that under NF0, WM was significantly associated with sentence recognition in quiet, and both VIQ and WM were significantly associated with performance in noise. NVIQ showed no significant association under any listening condition. When F 0 contours were flattened, none of the cognitive measures correlated with recognition accuracy. Conclusions: Autistic children rely on intact prosodic cues for sentence intelligibility, and higher order verbal abilities and working memory can only compensate when these cues are preserved. Therefore, interventions should integrate prosody-focused listening training with support for cognitive–linguistic skills to enhance speech comprehension in autistic individuals.