Articulatory strategy as a source of variation in acoustic vowel dynamics

2026-05-22

AI Summary

This study investigates how articulatory strategies systematically influence vowel acoustic dynamics, focusing on the palatalized vowel /i/ and formant trajectories in diphthongs containing a palatal glide. Using ultrasound tongue imaging and acoustic analysis of 36 speakers of Northern English English, the research empirically demonstrates—for the first time—a systematic relationship between tongue shape, particularly retraction or dorsum displacement, and formant dynamics: greater posterior tongue body displacement correlates with earlier onset and steeper slope of formant transitions. These findings elucidate the direct impact of articulatory movements on acoustic output under vocal tract morphological constraints, reconciling individual variation with universal principles in articulatory compensation mechanisms.

Abstract

Acoustic vowel dynamics have some speaker-identifying characteristics, which have been ascribed to individual properties of articulatory strategies: formant transitions have a particular shape because speakers move their articulators, using specific and practised movements. However, there is little existing evidence that different articulatory strategies systematically affect formant dynamics. The present study corroborates the link between the two. Ultrasound tongue imaging data from 36 speakers of Northern-Anglo English are used to identify distinct articulatory strategies for the production of palatal vowel /i/. Tongue shape in /i/ is found to be a significant predictor of formant dynamics in diphthongs with a palatal offglide. The observed relationships can be explained by the characteristics of articulatory movement conditioned by vocal tract shape. Greater articulatory displacement of tongue root and/or dorsum produces greater distortion from the mean tongue shape in palatal vowels, and it also requires higher articulatory velocities, resulting in relatively earlier and steeper formant transitions. The results contribute to the conceptual understanding of individuality in speech, by illuminating the regularising and individual aspects of articulatory compensation.

Problem

• articulatory strategy
• acoustic vowel dynamics
• formant dynamics
• speaker individuality
• tongue movement

Innovation

• articulatory strategy
• formant dynamics
• ultrasound tongue imaging
• vocal tract shape
• speaker individuality