Maintenance of the COT-CAUGHT Contrast Among Metro Detroit Speakers: A Multimodal Articulatory Analysis

While the acoustic characteristics of the Northern Cities Vowel Shift (NCVS) are well documented, research on the articulatory component of this shift is comparatively limited. This study combines acoustic, video, and ultrasound analysis to examine the productions of six Metro Detroit speakers in order to determine the relative contributions of lip configuration and tongue position to the production of fronted COT and CAUGHT. NCVS speakers are found to exhibit variation with regard to how this change is achieved articulatorily. While some speakers distinguish CAUGHT from COT with a combination of tongue position and lip rounding, others do so using either tongue position or lip rounding alone. For speakers who maintain the contrast with only one articulatory gesture, COT and CAUGHT are acoustically more similar than for speakers who use multiple gestures.