ISCA Archive ISAPh 2024
ISCA Archive ISAPh 2024

Backchannel and Filled Pause by Taiwan Mandarin Speakers with Autism

Vanessa Shih-Han Wu, Ying Hsun Liu, Shaoren Lyu, Ho-hsien Pan, Susan Shur-Fen Gau

This study examines how native Mandarin speakers with Autistic Spectrum Disorder (ASD) produce the discourse marker [ən] “嗯” which functions pragmatically either as backchannel (BC) or filled pauses (FP). Acoustic cues, including f0 range and Harmonic-to-Noise-Ratio up to 2500 Hz (HNR25), were extracted from the [ən] syllables produced by speakers with ASD or gender- and age-matched comparison groups. Intragroup results showed that some comparison subgroups produced significantly smaller f0 ranges or larger HNR25 for FP than for BC. However, autistic females and children did not distinguish FP and BC at all. Only autistic male youths exhibited significantly higher HNR25 for FP than BC. Inter-group results showed that the autistic youths produced both FP and BC with significantly larger f0 ranges and higher HNR25 than non-ASD youths. In summary, speakers with ASD tend not to distinguish the pragmatic FP and BC functions of [ən]. However, in general, they exhibited a more curved pitch contours and more periodic voice quality for both FP and BC. It is suggested that speakers with ASD speakers produce canonical form but non-autistic speakers may reduce articulatory efforts and produced weakened form for the highfrequency discourse marker [ən].