C-V coarticulation in velar plosives

We present 114 fps lingual ultrasound data of three speakers’ productions of words containing the initial velar plosive, and the following [a] and [i] vowels, in Mangetti Dune !Xung (N = 95 for [k] in the [a] context, N = 36 for [k] in the [i] context). We traced the midsaggital tongue edge at the frame just prior to the [k] release, and measured the tongue dorsum (TD) and tongue root (TR) constriction locations (CL’s). The TRCL was measured 1 cm below the [k] peak. Results show that [k] in the [i] context has a 1.1 cm further forward TDCL than [k] in the [a] context for one speaker, and 1.2 cm further forward for the second speaker. The results are similar to those found for English by Stevens and House (1963). The TRCL is retracted 0.3 cm in [k] in the [a] context compared with [k] in the [i] context for the first speaker, and 0.6 cm more retracted for the second speaker. A third speaker had a retracted TDCL and TRCL in both vowel contexts. These results confirm that [k] is less resistant to coarticulation. Results show that the tongue root is involved in dorsal-front vowel coarticulation.