Variation in compensatory strategies as a function of target constriction degree in post-glossectomy speech.

Individuals who have undergone treatment for oral cancer oftentimes exhibit compensatory behavior in consonant production. This pilot study investigates whether compensatory mechanisms utilized in the production of speech sounds with a given target constriction location vary systematically depending on target manner of articulation. The data reveal that compensatory strategies used to produce target alveolar segments vary systematically as a function of target manner of articulation in subtle yet meaningful ways. When target constriction degree at a particular constriction location cannot be preserved, individuals may leverage their ability to finely modulate constriction degree at multiple constriction locations along the vocal tract.

Complexity of vocal tract shaping in glossectomy patients and typical speakers: A principal component analysis.

The glossectomy procedure, involving surgical resection of cancerous lingual tissue, has long been observed to affect speech production. This study aims to quantitatively index and compare complexity of vocal tract shaping due to lingual movement in individuals who have undergone glossectomy and typical speakers using real-time magnetic resonance imaging data and Principal Component Analysis. The data reveal that (i) the type of glossectomy undergone largely predicts the patterns in vocal tract shaping observed, (ii) gross forward and backward motion of the tongue body accounts for more change in vocal tract shaping than do subtler movements of the tongue (e.g., tongue tip constrictions) in patient data, and (iii) fewer vocal tract shaping components are required to account for the patients' speech data than typical speech data, suggesting that the patient data at hand exhibit less complex vocal tract shaping in the midsagittal plane than do the data from the typical speakers observed.

Changes in Articulatory Control Pre- and Post-Facial Transplant: A Case Report.

Purpose Facial transplantation involves partial or total replacement of neuromuscular and skeletal structures of the face, head, and neck using donor tissues and is among the most extensive facial reconstructive procedures. This case report compares changes in speech production and articulator movement in a 44-year-old man from pretransplant to a 13-month posttransplant period. Method Speech production and articulator movement data were examined at 5 time points, once pretransplant and 4 times posttransplant (4, 7, 10, and 13 months), and compared to 4 healthy controls. A motion capture system was used to track jaw and vertical/horizontal lip movement during nonspeech and speech tasks. Speech intelligibility, jaw displacement, lip aperture, and movement variability were measured. Results Speech intelligibility varied across the study period and was restored to control status by 7 months posttransplant. Jaw displacement and lip aperture in the vertical plane significantly increased over time for nonspeech and speech tasks. Changes in horizontal lip movements over time were minimal. Jaw and lip movement variability fluctuated over time and was greater than the controls by 13 months posttransplant. Discussion Findings quantify changes in articulator movement and contributions to improved speech production following facial transplant. Changes reflect the adaptability of the speech motor system and are discussed in relation to pretransplant speech motor control patterns.

Characterizing Articulation in Apraxic Speech Using Real-Time Magnetic Resonance Imaging.

Purpose: Real-time magnetic resonance imaging (MRI) and accompanying analytical methods are shown to capture and quantify salient aspects of apraxic speech, substantiating and expanding upon evidence provided by clinical observation and acoustic and kinematic data. Analysis of apraxic speech errors within a dynamic systems framework is provided and the nature of pathomechanisms of apraxic speech discussed. Method: One adult male speaker with apraxia of speech was imaged using real-time MRI while producing spontaneous speech, repeated naming tasks, and self-paced repetition of word pairs designed to elicit speech errors. Articulatory data were analyzed, and speech errors were detected using time series reflecting articulatory activity in regions of interest. Results: Real-time MRI captured two types of apraxic gestural intrusion errors in a word pair repetition task. Gestural intrusion errors in nonrepetitive speech, multiple silent initiation gestures at the onset of speech, and covert (unphonated) articulation of entire monosyllabic words were also captured. Conclusion: Real-time MRI and accompanying analytical methods capture and quantify many features of apraxic speech that have been previously observed using other modalities while offering high spatial resolution. This patient's apraxia of speech affected the ability to select only the appropriate vocal tract gestures for a target utterance, suppressing others, and to coordinate them in time.