Lip Tracking and Acoustics at the Phonetics–Phonology Interface: Coronal Stop Deletion in American English

Abstract

American English is well-known for optional /t d/ deletion in clusters, as in best [bes] man, kept [khep] going or whipped [wɪp] butter. However, research shows that even in the absence of an acoustic trace of /t d/, articulatory gestures related to the alveolar constriction are still there, although they may be of a smaller magnitude, which questions the completeness of deletion from a phonological standpoint. This study uses motion capture to look at /t d/ trapped in between consonants vs a neutral context and explore the interplay of acoustics with articulation. The results show significant differences between sequences with deleted and retained coronals in both lips and acoustic measurements. Some gradient effects and weakening strategies are also discussed, pointing to the need for a more wholesome approach to the study of (apparent) sound deletion in the context of overall articulatory strategies.