title: A fast and flexible MRI system for the study of dynamic vocal tract shaping.
abstract: 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.
  
  
  
  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.
  
  
  
  We report spatiotemporal resolutions of 2.4 × 2.4 mm2every 12 ms for single-slice imaging, and 2.4 × 2.4 mm2every 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.
  
  
  
  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.
authors.affiliation: Electrical Engineering, University of Southern California, Los Angeles, CA.
authors.forename: Sajan Goud
authors.initials: SG
authors.lastname: Lingala
authors.affiliation: Electrical Engineering, University of Southern California, Los Angeles, CA.
authors.forename: Yinghua
authors.initials: Y
authors.lastname: Zhu
authors.affiliation: Samsung Medical Center, Seoul, South Korea.
authors.forename: Yoon-Chul
authors.initials: YC
authors.lastname: Kim
authors.affiliation: Electrical Engineering, University of Southern California, Los Angeles, CA.
authors.forename: Asterios
authors.initials: A
authors.lastname: Toutios
authors.affiliation: Electrical Engineering, University of Southern California, Los Angeles, CA.
authors.forename: Shrikanth
authors.initials: S
authors.lastname: Narayanan
authors.affiliation: Electrical Engineering, University of Southern California, Los Angeles, CA.
authors.forename: Krishna S
authors.initials: KS
authors.lastname: Nayak
mesh_terms: D000328:Adult; D000465:Algorithms; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D012815:Signal Processing, Computer-Assisted; D059629:Signal-To-Noise Ratio; D013018:Sound Spectrography / Q000379:methods*; D013060:Speech / Q000502:physiology*; D014062:Tongue Neoplasms / Q000000981:diagnostic imaging; D014827:Vocal Cords / Q000000981:diagnostic imaging*
keywords: constrained reconstruction; custom upper-airway coil; flexible MRI system; multi-slice; rapid vocal tract shaping; spiral readouts