An approach to real-time magnetic resonance imaging for speech production

TLDR

MRI has been used to study static speech postures, and recent temporal resolution advances now enable examination of dynamic vocal‑tract shaping during fluent speech. The study aims to examine the dynamics of vocal‑tract shaping during fluent speech using MRI. Using spiral k‑space acquisitions with a low‑flip‑angle gradient‑echo sequence on a GE Signa 1.5‑T scanner, the authors achieved 8–9 images/s acquisition and 20–24 images/s reconstruction, enabling veridical movies that allow quantitative evaluation of segmental durations, positions, and interarticulator timing. The data reveal clear real‑time movements of the lips, tongue, and velum, and the authors present sample movies and analysis strategies.

Abstract

Magnetic resonance imaging (MRI) has served as a valuable tool for studying static postures in speech production. Now, recent improvements in temporal resolution are making it possible to examine the dynamics of vocal-tract shaping during fluent speech using MRI. The present study uses spiral k-space acquisitions with a low flip-angle gradient echo pulse sequence on a conventional GE Signa 1.5-T CV/i scanner. This strategy allows for acquisition rates of 8–9 images per second and reconstruction rates of 20–24 images per second, making veridical movies of speech production now possible. Segmental durations, positions, and interarticulator timing can all be quantitatively evaluated. Data show clear real-time movements of the lips, tongue, and velum. Sample movies and data analysis strategies are presented.