Articulatory Strategies for Place Contrasts of Unreleased Final Stops on Preceding Vowels: Evidence from Ultrasound Imaging

Suki Yiu,Jonathan Yip,Diana Archangeli

doi:10.3765/amp.v9i0.4904

Abstract

This ultrasound study examines the gestural coordination involved in vowel-to-consonant sequences concerning unreleased final stops, which are more susceptible to reduction than their released counterparts. Thus, coarticulatory information on the preceding vowel is important to signal place contrasts of post-vocalic stops. The gestural coordination of vowel-consonant sequences of monosyllabic words in Cantonese represents a testing case for having preserved phonemic contrasts of six unreleased final stops in a range of vowel contexts. Preliminary results from smoothing spline ANOVA and linear mixed-effect regression show that coarticulatory patterns depend on vowel height, that is, non-high vowels are undergoing gradual coarticulation whereas high vowels are phonologising the lingual properties of the unreleased final stops on the preceding vowels.

Highlights

Unreleased final stops are susceptible to reduction, rendering coarticulatory information on the preceding vowel important to signal place contrasts of these postvocalic stops
For non–high vowels, gestural changes are highly significant from vowel onset to midpoint for coronals, from vowel midpoint to offset for both coronals and for dorsals, and from vowel onset to offset for both coronals and dorsals, indicating gradual consonant–to–vowel coarticulation
Gestural changes for high vowels are mainly reported from vowel onset to midpoint, indicating early lingual raising from vowel onset to midpoint into final stop constrictions, which is different from approaching to a gestural target over the entire course as for non-high vowels, and closer to the stage of phonologisation

Summary

Introduction

Unreleased final stops are susceptible to reduction, rendering coarticulatory information on the preceding vowel important to signal place contrasts of these postvocalic stops. This study has employed ultrasound imaging to examine the lingual properties of the place of articulation of unreleased final stops on the preceding vowels. The gestural coordination of vowel–consonant sequences of monosyllabic words in Cantonese represents a testing case for having preserved phonemic contrasts of six unreleased final stops in a range of vowel contexts. In Cantonese, unreleased final stops /p/, /t/, /k/, /m/, /n/ and /ŋ/ can be preceded by vowels such as /i/, /ɐ/, /a/, /ɔ/ and /u/. Khouw and Ciocca’s (2006) acoustic study found that unreleased final stops in Cantonese use consonant–to–vowel coarticulation to strengthen place contrasts, providing us an acoustic ground for verification. In Cantonese, unreleased final stops /p/, /t/, /k/, /m/, /n/ and /ŋ/ can be preceded by vowels such as /i/, /ɐ/, /a/, /ɔ/ and /u/. Khouw and Ciocca’s (2006) acoustic study found that unreleased final stops in Cantonese use consonant–to–vowel coarticulation to strengthen place contrasts, providing us an acoustic ground for verification.

Methods

Results

Conclusion