Development of Phonetic Contrasts in Cantonese Tone Acquisition

Why Aren't All Cantonese Tones Equally Confusing to English Listeners?

English listeners often struggle to perceive tones, but some are easier than others. This study examined these phenomena grounded in the feature weighing perspective (FWP) and the Perceptual Assimilation Model for Suprasegmentals (PAM-S). Forty-seven English and Cantonese listeners completed 4,212 trials of Cantonese tone discrimination and sequence recall tasks. The English listeners showed asymmetrical perceptual patterns of discrimination but not sequence recall. Specifically, these English listeners discriminated T1-T5, T3-T5, and T4-T5 more accurately than T1-T4, T3-T4, and T1-T3. However, they recalled the contour tone and level tone sequences with similar accuracies. Results of the discrimination task aligned with the predictions of PAM-S but not FWP. However, results of the sequence recall task did not support PAM-S. Together, these results suggest that PAM-S only applies to simple discrimination, not abstract phonological processing with a high memory load.

Just-Noticeable Differences of Fundamental Frequency Change in Mandarin-Speaking Children with Cochlear Implants

Fundamental frequency (F0) provides the primary acoustic cue for lexical tone perception in tonal languages but remains poorly represented in cochlear implant (CI) systems. Currently, there is still a lack of understanding of sensitivity to F0 change in CI users who speak tonal languages. In the present study, just-noticeable differences (JNDs) of F0 contour and F0 level changes in Mandarin-speaking children with CIs were measured and compared with those in their age-matched normal-hearing (NH) peers. Results showed that children with CIs demonstrated significantly larger JND of F0 contour (JND-C) change and F0 level (JND-L) change compared to NH children. Further within-group comparison revealed that the JND-C change was significantly smaller than the JND-L change among children with CIs, whereas the opposite pattern was observed among NH children. No significant correlations were seen between JND-C change/JND-L change and age at implantation /duration of CI use. The contrast between children with CIs and NH children in sensitivity to F0 contour and F0 level change suggests different mechanisms of F0 processing in these two groups as a result of different hearing experiences.

Linguistic Tone and Non-Linguistic Pitch Imitation in Children with Autism Spectrum Disorders: A Cross-Linguistic Investigation

The conclusions on prosodic pitch features in autism spectrum disorders (ASD) have primarily been derived from studies in non-tonal language speakers. This cross-linguistic study evaluated the performance of imitating Cantonese lexical tones and their non-linguistic (nonspeech) counterparts by Cantonese- and Mandarin-speaking children with and without ASD. Acoustic analyses showed that, compared with typically developing peers, children with ASD exhibited increased pitch variations when imitating lexical tones, while performed similarly when imitating the nonspeech counterparts. Furthermore, Mandarin-speaking children with ASD failed to exploit the phonological knowledge of segments to improve the imitation accuracy of non-native lexical tones. These findings help clarify the speech-specific pitch processing atypicality and phonological processing deficit in tone-language-speaking children with ASD.