About

Professor Ryan Keith Shosted is an experimental phonetician and phonologist at the University of Illinois at Urbana-Champaign. His research focuses on how phonetic principles shape phonological, typological, and diachronic outcomes in language. He specializes in the production of speech, examining acoustics, kinematics, and aerodynamics. His research group has made significant advances using ultra-fast magnetic resonance imaging to study speech. He works toward models of speech production built on data from typologically and geographically diverse languages, including understudied and endangered languages. Additionally, he gains insights into historical sound change by studying writing systems such as Hittite cuneiform and the Deseret Alphabet.

Research topics

• Computer Science
• Artificial Intelligence
• Speech recognition
• Linguistics
• Computer vision
• Physics
• Philosophy
• Geotechnical engineering
• Medicine
• Database
• Mechanics
• Geography
• Radiology
• Algorithm
• Archaeology
• Mathematics
• Geology
• Acoustics

Selected publications

• Spatiotemporal atlas driven reconstruction of dynamic speech imaging

  Proceedings on CD-ROM - International Society for Magnetic Resonance in Medicine. Scientific Meeting and Exhibition/Proceedings of the International Society for Magnetic Resonance in Medicine, Scientific Meeting and Exhibition · 2024-11-26

  article

  Motivation: Individuals across a population typically exhibit similar articulatory movements when performing speech tasks with specific speech samples. From an imaging experiment, we are interested in representing how an individual’s speech behavior is different from the ‘standard’ motion, which assists the preoperative planning of velopharyngeal surgery. Goal(s): We expected to visualize velopharyngeal variations between individual subjects and the average population. Approach: We have integrated an atlas into a low-rank residual reconstruction framework to capture the distinctive motion variations unique to each subject. Results: We demonstrated the ability of the method to visualize velopharyngeal variations as well as enhancing the quality of the reconstruction process. Impact: By applying a spatio-temporal atlas-driven reconstruction method, we were able to visualize and analysis velopharyngeal variations between individuals and the average population which will specifically benefit the surgical planning of individual cleft palate patients.

  PublisherDOI

• Speech Aerodynamics

  Elsevier eBooks · 2024-01-01

  book-chapter1st authorCorresponding
  PublisherDOI

• Preliminary Development of an MRI Atlas for Application to Cleft Care: Findings and Future Recommendations

  The Cleft Palate-Craniofacial Journal · 2023-06-19 · 8 citations

  article

  OBJECTIVE: To introduce a highly innovative imaging method to study the complex velopharyngeal (VP) system and introduce the potential future clinical applications of a VP atlas in cleft care. DESIGN: Four healthy adults participated in a 20-min dynamic magnetic resonance imaging scan that included a high-resolution T2-weighted turbo-spin-echo 3D structural scan and five custom dynamic speech imaging scans. Subjects repeated a variety of phrases when in the scanner as real-time audio was captured. SETTING: Multisite institution and clinical setting. PARTICIPANTS: Four adult subjects with normal anatomy were recruited for this study. MAIN OUTCOME: Establishment of 4-D atlas constructed from dynamic VP MRI data. RESULTS: Three-dimensional dynamic magnetic resonance imaging was successfully used to obtain high quality dynamic speech scans in an adult population. Scans were able to be re-sliced in various imaging planes. Subject-specific MR data were then reconstructed and time-aligned to create a velopharyngeal atlas representing the averaged physiological movements across the four subjects. CONCLUSIONS: The current preliminary study examined the feasibility of developing a VP atlas for potential clinical applications in cleft care. Our results indicate excellent potential for the development and use of a VP atlas for assessing VP physiology during speech.

  PublisherDOI

• 3D Dynamic Magnetic Resonance Imaging: A Tool for Describing Velopharyngeal Function

  Proceedings on CD-ROM - International Society for Magnetic Resonance in Medicine. Scientific Meeting and Exhibition/Proceedings of the International Society for Magnetic Resonance in Medicine, Scientific Meeting and Exhibition · 2023-08-03

  article

  Direct visualization of velopharyngeal structures and musculature during speech is best attained using 3D dynamic magnetic resonance imaging. Through innovative MR imaging and atlasing methods, we successfully describe velopharyngeal contours as represented on MR statistical atlases and individual subject images. Manual linear measurements of velum configurations during /p/ across two different speech stimuli reveal slight velar differences, reflecting major influences of neighboring speech sounds on velar movements.

  PublisherDOI

• Enhancing linguistic research through 2-mm isotropic 3D dynamic speech magnetic resonance imaging

  Proceedings on CD-ROM - International Society for Magnetic Resonance in Medicine. Scientific Meeting and Exhibition/Proceedings of the International Society for Magnetic Resonance in Medicine, Scientific Meeting and Exhibition · 2023-08-03

  article

  We are able to push the spatial resolution of dynamic speech magnetic resonance imaging to 2-mm near-isotropic level with 64 mm coverage of 32 3D slice locations that are spaced 2-mm apart with 35 fps. We choose to analyze lingual differences of American English voiced lateral [l] and (central) [t]. Several analysing methods are utilized such as magnitude comparison, t-test and deformation map comparison. The results give us detailed observations of lingual articulatory differences such as tongue grooving, twisting and coarticulation. Through this high spatial and temporal resolution, we demonstrate that this method will show great potentials on linguistic research.

  PublisherDOI

• Optimization of 3D dynamic speech <scp>MRI</scp>: Poisson‐disc undersampling and locally higher‐rank reconstruction through partial separability model with regional optimized temporal basis

  Magnetic Resonance in Medicine · 2023-09-07 · 6 citations

  articleOpen access

  PURPOSE: To improve the spatiotemporal qualities of images and dynamics of speech MRI through an improved data sampling and image reconstruction approach. METHODS: For data acquisition, we used a Poisson-disc random under sampling scheme that reduced the undersampling coherence. For image reconstruction, we proposed a novel locally higher-rank partial separability model. This reconstruction model represented the oral and static regions using separate low-rank subspaces, therefore, preserving their distinct temporal signal characteristics. Regional optimized temporal basis was determined from the regional-optimized virtual coil approach. Overall, we achieved a better spatiotemporal image reconstruction quality with the potential of reducing total acquisition time by 50%. RESULTS: The proposed method was demonstrated through several 2-mm isotropic, 64 mm total thickness, dynamic acquisitions with 40 frames per second and compared to the previous approach using a global subspace model along with other k-space sampling patterns. Individual timeframe images and temporal profiles of speech samples were shown to illustrate the ability of the Poisson-disc under sampling pattern in reducing total acquisition time. Temporal information of sagittal and coronal directions was also shown to illustrate the effectiveness of the locally higher-rank operator and regional optimized temporal basis. To compare the reconstruction qualities of different regions, voxel-wise temporal SNR analysis were performed. CONCLUSION: Poisson-disc sampling combined with a locally higher-rank model and a regional-optimized temporal basis can drastically improve the spatiotemporal image quality and provide a 50% reduction in overall acquisition time.

  PublisherOA PDFDOI

• Travertine crystal growth ripples record the hydraulic history of ancient Rome’s Anio Novus aqueduct

  Scientific Reports · 2022 · 14 citations

  • Geology
  • Geotechnical engineering
  • Mechanics

  Travertine crystal growth ripples are used to reconstruct the early hydraulic history of the Anio Novus aqueduct of ancient Rome. These crystalline morphologies deposited within the aqueduct channel record the hydraulic history of gravity-driven turbulent flow at the time of Roman operation. The wavelength, amplitude, and steepness of these travertine crystal growth ripples indicate that large-scale sustained aqueduct flows scaled directly with the thickness of the aqueous viscous sublayer. Resulting critical shear Reynolds numbers are comparable with those reconstructed from heat/mass transfer crystalline ripples formed in other natural and engineered environments. This includes sediment transport in rivers, lakes, and oceans, chemical precipitation and dissolution in caves, and melting and freezing in ice. Where flow depth and perimeter could be reconstructed from the distribution and stratigraphy of the travertine within the Anio Novus aqueduct, flow velocity and rate have been quantified by deriving roughness-flow relationships that are independent of water temperature. More generally, under conditions of near-constant water temperature and kinematic viscosity within the Anio Novus aqueduct channel, the travertine crystal growth ripple wavelengths increased with decreasing flow velocity, indicating that systematic changes took place in flow rate during travertine deposition. This study establishes that travertine crystal growth ripples such as those preserved in the Anio Novus provide a sensitive record of past hydraulic conditions, which can be similarly reconstructed from travertine deposited in other ancient water conveyance and storage systems around the world.

  PublisherOA PDFDOI

• Enhancing linguistic research through 2‐mm isotropic <scp>3D</scp> dynamic speech MRI optimized by sparse temporal sampling and low‐rank reconstruction

  Magnetic Resonance in Medicine · 2022 · 21 citations

  • Computer Science
  • Artificial Intelligence
  • Computer Science

  PURPOSE: To enable a more comprehensive view of articulations during speech through near-isotropic 3D dynamic MRI with high spatiotemporal resolution and large vocal-tract coverage. METHODS: Using partial separability model-based low-rank reconstruction coupled with a sparse acquisition of both spatial and temporal models, we are able to achieve near-isotropic resolution 3D imaging with a high frame rate. The total acquisition time of the speech acquisition is shortened by introducing a sparse temporal sampling that interleaves one temporal navigator with four randomized phase and slice-encoded imaging samples. Memory and computation time are improved through compressing coils based on the region of interest for low-rank constrained reconstruction with an edge-preserving spatial penalty. RESULTS: spatial resolution, 64-mm through-plane coverage, and a 35.6-fps temporal resolution are achieved. Investigations and analysis on specific speech samples support novel insights into nonsymmetric tongue movement, velum raising, and coarticulation events with adequate visualization of rapid articulatory movements. CONCLUSION: Three-dimensional dynamic images of the vocal tract structures during speech with high spatiotemporal resolution and axial coverage is capable of enhancing linguistic research, enabling visualization of soft tissue motions that are not possible with other modalities.

  PublisherOA PDFDOI

• Articulatory and acoustic correlates of pharyngealization and pharyngealization spread in Cairene Arabic: A real-time magnetic resonance imaging study

  2021

  • Acoustics
  • Linguistics
  • Medicine
  Publisher

• Articulatory and acoustic correlates of pharyngealization andpharyngealization spread in Cairene Arabic

  Studies in Arabic linguistics · 2021 · 1 citations

  • Computer Science
  • Speech recognition
  • Linguistics

  Abstract Pharyngealized speech sounds in Arabic are articulated with a secondary posterior constriction and a lowered tongue body. This articulatory configuration spreads to adjacent and neighboring segments and has the acoustic consequence of lowering F2 in affected vowels. This study demonstrates that real-time Magnetic Resonance Imaging (rtMRI) can be successfully used to examine the role of (1) vowel length and (2) direction of spread in the extent of the articulatory modifications that occur in the segments to which pharyngealization spreads. Parallel acoustic measurements are also acquired to examine and compare the extent of modifications in formant frequencies. Results from both articulatory and acoustic data demonstrate that the extent of pharyngealization spread significantly varies with respect to these two factors.

  PublisherDOI

Recent grants

• Doctoral Dissertation Research: Articulatory and acoustic patterns in phonemic and phonetic nasalization

  NSF · $10k · 2017–2018

• Doctoral Dissertation Research: Oral Articulation of French Nasal Vowels

  NSF · $12k · 2011–2013

Frequent coauthors

• Bradley P. Sutton

  25 shared

• Zhi‐Pei Liang

  19 shared

• Fangxu Xing

  Harvard University

  15 shared

• Jonghye Woo

  15 shared

• Maojing Fu

  University of Illinois Urbana-Champaign

  12 shared

• Marissa Barlaz

  University of Illinois Urbana-Champaign

  11 shared

• Torrey M. Loucks

  11 shared

• Christopher Carignan

  University College London

  10 shared

Awards & honors

• Jacob K. Javits Fellowship