Acoustic Study in Mandarin-Speaking Children: Developmental Changes in Vowel Production

Background: Acoustic analysis had been well incorporated into clinical evaluation andmanagement of children with speech disorders for many years. The aim ofthis study is to investigate developmental changes in vowel production inMandarin-speaking children using acoustic study analysis.Methods: A total of 22 children from 5-12 years old were analyzed in this study. Eachchild read a list of speech materials consisting of 6 dissyllabic words inMandarin phonemes and the speech samples were recorded. The digitizedacoustic recordings were submitted for acoustic analysis. The acoustic parametersin this study include the first and second formant frequencies (F1 andF2) of /a/, /i/ and /u/ and the vowel space. We used the Wilcoxon rank sumtest and Spearman’s rho correlation test for statistical analysis.Results: The F1 values of the vowel /i/ were significantly lower in boys than those ingirls (p = 0.013) by Wilcoxon ranksum test. The F1 value of the vowel /i/was negatively correlated with children’s age (rho = –0.601, p = 0.003) andtheir body height (rho = 0.478 p = 0.045). The F1 values of the other twovowels (/u/ and /a/), the F2 values of all three vowels and the vowel spacehad no association with age and gender.Conclusions: F1 acoustic parameters have developmental and gender changes in vowelproduction in Mandarin-speaking children. The data in this study providereferences for acoustic assessment of Mandarin-speaking children.