第22屆 華語嬰幼兒語速分析

Speech rate in Mandarin-learning infants

華語嬰幼兒語速分析

李書葳¹、陳俐文²、陳麗美³

Shu-Wei Lee¹, Li-Wen Chen², Li-Mei Chen³

¹國立成功大學外文系（所）大學生、²國立成功大學醫學院小兒科主治醫師

³國立成功大學外文系（所）教授

¹Undergraduate student, Dept. of Foreign Languages and Literature, National Cheng Kung University

²Medical Doctor, Department of Pediatrics, National Cheng Kung University Hospital

³Professor, Dept. of Foreign Languages and Literature, National Cheng Kung University

Background and purpose: Speech rate plays an important role in speech and language development. It is also one of the reference indexes in early intervention for speech disorders. This research investigated utterance duration, word duration, and speaking rate of Mandarin-learning children aged four mouths to one and a half years. This research can fill the gap in the age range of available data and be a reference for clinical evaluation.

Methods: The data includes six recording files of spontaneous interactions from children aged 4-18 months. Each file lasted about 50 minutes. The beginning and ending points in each utterance were marked via Praat in order to analyze speaking rate, articulation rate, mean utterance duration, mean word duration, pause ratio, MLU, and volubility.

Results: Three major findings in this research are: 1) Speaking rate, articulation rate, mean utterance duration, and MLU all got some improvement from 12 to 18 months of age; 2) The developmental changes of articulation rate between 12 to 18 months (increased about 1.08 word/ sec) was sharper than the one between 4 to 12 months (increased about 0.037 word/ sec); 3) Articulation rate, pause ratio, and MLU improved with age. In contrast, mean word utterance and volubility declined; 4) There were no significant correlations between speaking rate and articulation rate.

Conclusions: This research focused on data from infants under 2 year old which might make the available data from the literature more complete, and thus could provide reference for clinical assessment and intervention. However, these six recordings were not sound evidences to draw a general conclusion. First, data from four children were not necessarily a good indicator of developmental trends which usually should incorporate data from more children at young ages. Second, different family backgrounds and interactions should also take into consideration in future studies.

Key words: speaking rate, articulation rate, typically developing infants.