Recovery of speech following total glossectomy: an acoustic and perceptual appraisal

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.

Volume and location of the defect as predictors of speech outcome after glossectomy: correlation with a classification

The evaluation of speech outcomes after resection and reconstruction of the oral tongue remains largely unsystematic. A cross-sectional study was performed to analyse the speech outcomes of patients who underwent curative treatment with appropriate reconstruction. Sixty-nine patients were assessed for speech intelligibility and phonetics using a validated speech intelligibility assessment tool in the local language. Volume defects were classified as class I (less than one third), II (one third to half), III (half to two-thirds), or IV (two-thirds to total glossectomy). Defect location was defined as lateral, tip, or sulcus. The χ² test and Kruskal-Wallis test were used to test volume and location as predictors. Twenty-six patients had class I defects, 29 had class II defects, seven had class III defects, and seven had class IV defects. Twenty-two patients (31.9%) received adjuvant radiotherapy. Mean vowel, consonant, word, and paragraph intelligibility were 99.27%, 86.86%, 85.52%, and 88.72%, respectively. The incremental volume of the glossectomy defect was significantly correlated with speech intelligibility scores and phonatory alterations. In classes II and III, tip resection significantly affected interdental sounds. All patients in class III had affected alveolar and alveo-palatal sounds. The results positively corroborated the volume and location of the glossectomy defect to a classification system.

What Acoustic Studies Tell Us About Vowels in Developing and Disordered Speech

Purpose Literature was reviewed on the development of vowels in children's speech and on vowel disorders in children and adults, with an emphasis on studies using acoustic methods. Method Searches were conducted with PubMed/MEDLINE, Google Scholar, CINAHL, HighWire Press, and legacy sources in retrieved articles. The primary search items included, but were not limited to, vowels, vowel development, vowel disorders, vowel formants, vowel therapy, vowel inherent spectral change, speech rhythm, and prosody. Results/Discussion The main conclusions reached in this review are that vowels are (a) important to speech intelligibility; (b) intrinsically dynamic; (c) refined in both perceptual and productive aspects beyond the age typically given for their phonetic mastery; (d) produced to compensate for articulatory and auditory perturbations; (e) influenced by language and dialect even in early childhood; (f) affected by a variety of speech, language, and hearing disorders in children and adults; (g) inadequately assessed by standardized articulation tests; and (h) characterized by at least three factors-articulatory configuration, extrinsic and intrinsic regulation of duration, and role in speech rhythm and prosody. Also discussed are stages in typical vowel ontogeny, acoustic characterization of rhotic vowels, a sensory-motor perspective on vowel production, and implications for clinical assessment of vowels.

Static measurements of vowel formant frequencies and bandwidths: A review

PURPOSE

Data on vowel formants have been derived primarily from static measures representing an assumed steady state. This review summarizes data on formant frequencies and bandwidths for American English and also addresses (a) sources of variability (focusing on speech sample and time sampling point), and (b) methods of data reduction such as vowel area and dispersion.

METHOD

Searches were conducted with CINAHL, Google Scholar, MEDLINE/PubMed, SCOPUS, and other online sources including legacy articles and references. The primary search items were vowels, vowel space area, vowel dispersion, formants, formant frequency, and formant bandwidth.

RESULTS

Data on formant frequencies and bandwidths are available for both sexes over the lifespan, but considerable variability in results across studies affects even features of the basic vowel quadrilateral. Origins of variability likely include differences in speech sample and time sampling point. The data reveal the emergence of sex differences by 4 years of age, maturational reductions in formant bandwidth, and decreased formant frequencies with advancing age in some persons. It appears that a combination of methods of data reduction provide for optimal data interpretation.

CONCLUSION

The lifespan database on vowel formants shows considerable variability within specific age-sex groups, pointing to the need for standardized procedures.

Effects of Aging on Vocal Fundamental Frequency and Vowel Formants in Men and Women

PURPOSE

This study reports data on vocal fundamental frequency (f_o) and the first four formant frequencies (F1, F2, F3, F4) for four vowels produced by speakers in three adult age cohorts, in a test of the null hypothesis that there are no age-related changes in these variables. Participants were 43 men and 53 women between the ages of 20 and 92 years.

RESULTS

The most consistent age-related effect was a decrease in f_o for women. Significant differences in F1, F2, and F3 were vowel-specific for both sexes. No significant differences were observed for the highest formant F4.

CONCLUSIONS

Women experience a significant decrease in f_o, which is likely related to menopause. Formant frequencies of the corner vowels change little across several decades of adult life, either because physiological aging has small effects on these variables or because individuals compensate for age-related changes in anatomy and physiology.

Phonologic and Acoustic Analysis of Speech Following Glossectomy and the Effect of Rehabilitation on Speech Outcomes

PURPOSE

Changes in acoustic features in the perioperative phase for elucidating the mechanisms of articulation disorder and the effect of perioperative rehabilitation were studied prospectively.

MATERIALS AND METHODS

Sixty-two patients with 62 tongue cancer were divided into a partial glossectomy group (n = 40) and a reconstruction group (n = 22). Acoustic characteristics were analyzed during the preoperative and postoperative periods and after rehabilitation using the first and second formants of the vowels /a/, /i/, and /u/; the triangular vowel space area (tVSA); and the slopes of formant transitions.

RESULTS

In the 2 groups, decreases in the tVSA and formant slopes were found from the preoperative to the postoperative period, and the acoustic characteristics of the reconstruction group especially improved to preoperative values after rehabilitation. Analysis of the postoperative period showed that acoustic characteristics were altered at the site of surgical resection.

CONCLUSION

Changes of acoustic variables are related to excision size and site, suggesting the distinctive tongue portion for the articulation of each speech sound. Perioperative rehabilitation could activate the articulators and increase the range of movement of the remaining tongue, especially the preserved anterior tongue.