Premium
A fast and flexible MRI system for the study of dynamic vocal tract shaping
Author(s) -
Lingala Sajan Goud,
Zhu Yinghua,
Kim YoonChul,
Toutios Asterios,
Narayanan Shrikanth,
Nayak Krishna S.
Publication year - 2017
Publication title -
magnetic resonance in medicine
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.696
H-Index - 225
eISSN - 1522-2594
pISSN - 0740-3194
DOI - 10.1002/mrm.26090
Subject(s) - vocal tract , computer science , temporal resolution , visualization , spiral (railway) , dynamic range , beat (acoustics) , speech production , speech recognition , artificial intelligence , acoustics , computer vision , physics , mathematics , mathematical analysis , quantum mechanics
Purpose The aim of this work was to develop and evaluate an MRI‐based system for study of dynamic vocal tract shaping during speech production, which provides high spatial and temporal resolution. Methods The proposed system utilizes (a) custom eight‐channel upper airway coils that have high sensitivity to upper airway regions of interest, (b) two‐dimensional golden angle spiral gradient echo acquisition, (c) on‐the‐fly view‐sharing reconstruction, and (d) off‐line temporal finite difference constrained reconstruction. The system also provides simultaneous noise‐cancelled and temporally aligned audio. The system is evaluated in 3 healthy volunteers, and 1 tongue cancer patient, with a broad range of speech tasks. Results We report spatiotemporal resolutions of 2.4 × 2.4 mm 2 every 12 ms for single‐slice imaging, and 2.4 × 2.4 mm 2 every 36 ms for three‐slice imaging, which reflects roughly 7‐fold acceleration over Nyquist sampling. This system demonstrates improved temporal fidelity in capturing rapid vocal tract shaping for tasks, such as producing consonant clusters in speech, and beat‐boxing sounds. Novel acoustic‐articulatory analysis was also demonstrated. Conclusion A synergistic combination of custom coils, spiral acquisitions, and constrained reconstruction enables visualization of rapid speech with high spatiotemporal resolution in multiple planes. Magn Reson Med 77:112–125, 2017. © 2016 Wiley Periodicals, Inc.