Sibilant production patterns in three generations of Guoyu-Taiwanese bilinguals

Abstract

This study investigates the effects of age and language dominance on sibilant production in a bilingual community. Guoyu (Taiwanese Mandarin) has 3 sibilants: alveolar /s/, retroflex /ʂ/ and alveolo-palatal /ɕ/, while Taiwanese (a Southern Min dialect) only has /s/, which is palatalized before /i/ and /io/. Productions of sibilant initial words were elicited using a word repetition task. Subjects were 30 adults in three age bands from 20-80 years, with the oldest being the most Taiwanese-dominant. The spectral centroid was obtained from the middle 40ms of each sibilant, along with the onset F2 of the following vowel. In the low-vowel /a/ context, the youngest speakers clearly separate /s/ in both languages from the Guoyu /ʂ/ and /ɕ/ along the centroid dimension. The /ʂ/ is then separated from /ɕ/ by F2. However, the oldest speakers show no clear separation of these sounds in terms of centroid, although Guoyu /ɕ/ can still be differentiated by F2. Also, the three generations demonstrated differences in the assimilation patterns of palatal sounds. The younger Guoyu-dominant speakers assimilated Taiwanese palatalized one to Guoyu /ɕ/ in both centroid and F2, while older speakers matched the Guoyu /s/~/ɕ/ distinction to that of the Taiwanese pattern.