Relative contribution of jaw and tongue to the vowel height dimension in American English.

Abstract

Vowels are typically described according to three articulatory dimensions: height, frontness, and rounding. Other researchers propose a role for the jaw in the height dimension. In the present study, we measured the relative contribution of the tongue and jaw for vocalic height distinction in American English vowels. Tongue and jaw motions were collected in six adult speakers for six vowels from all portions of the vowel space, embedded in [hVd] sequences. Tongue shape was captured via HOCUS (Haskins Optically Corrected Ultrasound System) which combines digital ultrasound imaging at 127 Hz with optical three‐dimensional tracking of infrared emitting diodes (IREDs) positioned on the speaker’s head and probe for subsequent decoupling of tongue motion from the jaw motion. Results showed a consistent role of the tongue in creating the vocalic constriction for the six subjects investigated, though with some idiosyncratic strategies. Jaw contribution was more sizable for vowel pairs traditionally contrasted by ...