Perception and Production of Pitch Information in Mandarin-Speaking Children with Autism Spectrum Disorders

This study investigated the categorical perception (CP) of linguistic pitch (lexical tones) and nonlinguistic pitch (pure tones), as well as tonal production in Mandarin-speaking children with autism spectrum disorders (ASD). A total of 26 Mandarin-speaking children with ASD and 29 age-matched typically developing (TD) children were recruited for this study. The Mandarin T2-T3 contrast and corresponding pure tones with identical pitch contours were adopted to assess the nuanced pitch processing abilities of the child participants via the CP paradigm. Accordingly, tonal production was focused on T2 and T3 with analyses of the dynamic pitch contours and tonal differentiation. Mandarin-speaking children with ASD exhibited atypical CP for linguistic pitch in comparison with their TD peers. However, the categorization of linguistic pitch exceeded that of nonlinguistic pitch among the ASD participants, indicating a global over local processing pattern contrary to autistic individuals in non-tonal languages. Additionally, despite atypical pitch contours in producing T2 and T3, the ASD group showed comparable differentiable degrees of the two tones in production to the TD group. Findings of this study served as a foray into contesting current theories' claims of local bias and/or global impairment in the autistic population, prompting further inspections on individuals with different language backgrounds and stimuli processing with various complexities. Additionally, findings of this study underscore the necessity of developing tailored assessments and interventions to enhance the perception and production of complex and confusable tones, thereby improving perceptual robustness and communication skills in Mandarin-speaking children with ASD.