Effects of consonant cluster syllabification on vowel-to-vowel coarticulation in English

Abstract

This paper investigates how different syllable affiliations of intervocalic /st/ cluster affect vowel-to-vowel coarticulation in English. Very few studies have examined the effect of syllable structure on vowel-to-vowel coarticulation. Previous studies show that onset and coda consonants differ acoustically, articulatorily, perceptually and typologically. Onsets are stronger, more stable, more common and more distinguishable than codas. Since codas are less constrained, it was hypothesized that coda /st./ would allow more vowel-to-vowel coarticulation than onset /.st/. Three vowels (/i ɑ u/) were used to form the target sequences with the /st/ cluster in English: onset /CV.stVC/, heterosyllabic /CVs.tVC/, coda /CVst.VC/. F1 and F2 frequencies at vowel edges and the durations of the first vowel and the intervocalic consonants were measured from six speakers of Standard Southern British English. Factors included in the experiment are: Direction, Syllable Form, Target, Context. Results show that coda /st./ allows more vowel-to-vowel coarticulation than onset /.st/, and heterosyllabic /s.t/ is the most resistant among the Syllable Forms. Vowels in heterosyllabic /s.t/ are more extreme than in the other two Syllable Forms in the carryover direction. These findings suggest that vowel-to-vowel coarticulation is sensitive to different syllable structure with the same segmental composition. Possible factors contributing to the observed patterns are discussed.