Three-dimensional analysis of liquid sounds produced by first graders

Abstract

The liquids /r/ and /l/ in American English are complex sounds whose productions are highly variable among adult speakers, but there is currently little knowledge about how children articulate these sounds, which are typically acquired late in development. In this study, the Goldman-Fristoe Test of Articulation (GFTA-3) was administered to typically developing first graders (6 and 7 years old) while a 4D ultrasound system imaged the tongue with synchronous audio and webcam video recordings. The GFTA-3 contains words in which /r/ and /l/ occur in a variety of syllable positions and phonetic contexts. Among 14 first grade participants in this study, the so-called “bunched /r/” is overwhelmingly preferred over the so-called “retroflexed /r/.” In contrast, three-dimensional tongue shapes in the production of syllable initial /l/ are substantially more variable with two basic configurations (“coronal” and “dorsal”), while syllable final /l/ productions are more consistently “dorsal.” Examples of 3D tongue shapes will be presented, along with results from a Principal Components Analysis.