An ultrasound and tagged cine MRI study of German vowels

Abstract

German vowels contrast along the tense–lax as well as the rounding dimension, rendering a relatively complex (front) vowel system. The difference between tense and lax vowels is often described in terms of more extreme articulator movement and greater muscular tension for tense vowels, manifest especially in tongue root displacement and tongue height. These factors are assumed to correlate in the Germanic languages. This study uses ultrasound data to investigate global tongue shape and in particular tongue root differences for German monophthongs in stressed position. Preliminary results for one speaker indicate that some vowel pairs are nearly identical in tongue height, but differ in tongue root displacement. Rounded front vowels are more retracted and lower than their unrounded counterparts. The /a: a/ pair, which has been described as contrasting in duration only, exhibits a clear qualitative difference as well. In addition, tagged cine MRI data were collected for a subset of high and mid vowels. This technique allows inferring expansion and contraction of the tongue musculature and thus can inform about differences in muscular tension between tense and lax vowels. [Supported by NIH Grant RO1-DC01758.]