Improved imaging of lingual articulation using real-time multislice MRI
- PMID: 22127935
- PMCID: PMC3310329
- DOI: 10.1002/jmri.23510
Improved imaging of lingual articulation using real-time multislice MRI
Abstract
Purpose: To develop a real-time imaging technique that allows for simultaneous visualization of vocal tract shaping in multiple scan planes, and provides dynamic visualization of complex articulatory features.
Materials and methods: Simultaneous imaging of multiple slices was implemented using a custom real-time imaging platform. Midsagittal, coronal, and axial scan planes of the human upper airway were prescribed and imaged in real-time using a fast spiral gradient-echo pulse sequence. Two native speakers of English produced voiceless and voiced fricatives /f/-/v/, /θ/-/ð/, /s/-/z/, /∫/- in symmetrical maximally contrastive vocalic contexts /a_a/, /i_i/, and /u_u/. Vocal tract videos were synchronized with noise-cancelled audio recordings, facilitating the selection of frames associated with production of English fricatives.
Results: Coronal slices intersecting the postalveolar region of the vocal tract revealed tongue grooving to be most pronounced during fricative production in back vowel contexts, and more pronounced for sibilants /s/-/z/ than for /∫/-. The axial slice best revealed differences in dorsal and pharyngeal articulation; voiced fricatives were observed to be produced with a larger cross-sectional area in the pharyngeal airway. Partial saturation of spins provided accurate location of imaging planes with respect to each other.
Conclusion: Real-time MRI of multiple intersecting slices can provide valuable spatial and temporal information about vocal tract shaping, including details not observable from a single slice.
Copyright © 2011 Wiley Periodicals, Inc.
Figures






References
-
- Narayanan S, Nayak K, Lee S, Sethy A, Byrd D. An approach to real-time magnetic resonance imaging for speech production. J Acoust Soc Am. 2004;115(4):1771–1776. - PubMed
-
- Sutton BP, Conway CA, Bae Y, Seethamraju R, Kuehn DP. Faster dynamic imaging of speech with field inhomogeneity corrected spiral fast low angle shot (FLASH) at 3 T. J Magn Reson Imaging. 2010;32:1228–1237. - PubMed
-
- Demolin D, Hassid S, Metens T, Soquet A. Real-time MRI and articulatory coordination in speech. Comptes Rendus Biologies. 2002;325(4):547–556. - PubMed
-
- Bresch E, Kim YC, Nayak KS, Byrd D, Narayanan SS. Seeing speech: Capturing vocal tract shaping using real-time magnetic resonance imaging. IEEE Signal Processing Magazine. 2008:123–132.
-
- Narayanan SS, Alwan AA, Haker K. An articulatory study of fricative consonants using magnetic resonance imaging. J Acoust Soc Am. 1995;98(3):1325–1347.
Publication types
MeSH terms
Grants and funding
LinkOut - more resources
Full Text Sources
Medical