Acoustic vowel analysis and speech intelligibility in young adult Hebrew speakers: Developmental dysarthria versus typical development.

Publisher: Wiley Country of Publication: United States NLM ID: 9803709 Publication Model: Print-Electronic Cited Medium: Internet ISSN: 1460-6984 (Electronic) Linking ISSN: 13682822 NLM ISO Abbreviation: Int J Lang Commun Disord Subsets: MEDLINE

Publication: 2011- : Malden, MA : Wiley
Original Publication: London : Taylor & Francis for the Royal College of Speech & Language Therapists, c1998-

Dysarthria*/diagnosis ; Speech Intelligibility*; Acoustics ; Adolescent ; Humans ; Language ; Phonetics ; Speech Acoustics ; Speech Production Measurement ; Young Adult

Background: Developmental dysarthria is a motor speech impairment commonly characterized by varying levels of reduced speech intelligibility. The relationship between intelligibility deficits and acoustic vowel space among these individuals has long been noted in the literature, with evidence of vowel centralization (e.g., in English and Mandarin). However, the degree to which this centralization occurs and the intelligibility-acoustic relationship is maintained in different vowel systems has yet to be studied thoroughly. In comparison with American English, the Hebrew vowel system is significantly smaller, with a potentially smaller vowel space area, a factor that may impact upon the comparisons of the acoustic vowel space and its correlation with speech intelligibility. Data on vowel space and speech intelligibility are particularly limited for Hebrew speakers with motor speech disorders.
Aims: To determine the nature and degree of vowel space centralization in Hebrew-speaking adolescents and young adults with dysarthria, in comparison with typically developing (TD) peers, and to correlate these findings with speech intelligibility scores.
Methods & Procedures: Adolescents and young adults with developmental dysarthria (secondary to cerebral palsy (CP) and other motor deficits, n = 17) and their TD peers (n = 17) were recorded producing Hebrew corner vowels within single words. For intelligibility assessments, naïve listeners transcribed those words produced by speakers with CP, and intelligibility scores were calculated.
Outcomes & Results: Acoustic analysis of vowel formants (F1, F2) revealed a centralization of vowel space among speakers with CP for all acoustic metrics of vowel formants, and mainly for the formant centralization ratio (FCR), in comparison with TD peers. Intelligibility scores were correlated strongly with the FCR metric for speakers with CP.
Conclusions & Implications: The main results, vowel space centralization for speakers with CP in comparison with TD peers, echo previous cross-linguistic results. The correlation of acoustic results with speech intelligibility carries clinical implications. Taken together, the results contribute to better characterization of the speech production deficit in Hebrew speakers with motor speech disorders. Furthermore, they may guide clinical decision-making and intervention planning to improve speech intelligibility. What this paper adds What is already known on the subject Speech production and intelligibility deficits among individuals with developmental dysarthria (e.g., secondary to CP) are well documented. These deficits have also been correlated with centralization of the acoustic vowel space, although primarily in English speakers. Little is known about the acoustic characteristics of vowels in Hebrew speakers with motor speech disorders, and whether correlations with speech intelligibility are maintained. What this paper adds to existing knowledge This study is the first to describe the acoustic characteristics of vowel space in Hebrew-speaking adolescents and young adults with developmental dysarthria. The results demonstrate a centralization of the acoustic vowel space in comparison with TD peers for all measures, as found in other languages. Correlation between acoustic measures and speech intelligibility scores were also documented. We discuss these results within the context of cross-linguistic comparisons. What are the potential or actual clinical implications of this work? The results confirm the use of objective acoustic measures in the assessment of individuals with motor speech disorders, providing such data for Hebrew-speaking adolescents and young adults. These measures can be used to determine the nature and severity of the speech deficit across languages, may guide intervention planning, as well as measure the effectiveness of intelligibility-based treatment programmes.
(© 2021 Royal College of Speech and Language Therapists.)

Adank, Patti, Smits, Roel & van Hout, Roeland (2004) A comparison of vowel normalization procedures for language variation research. The Journal of the Acoustical Society of America, 116(5), 3099-3107.
Allison, K. M., Annear, L., Policicchio, M. and Hustad, K. C., 2017, Range and precision of formant movement in pediatric dysarthria. Journal of Speech, Language, and Hearing Research, 60(7), 1864-1876.
Amir, N. and Amir, O., 2007, Novel measures for vowel reduction. Proceedings of the 16th International Congress of Phonetic Sciences, (August), 849-852.
Amir, N., Tzenker, O., Amir, O. and Rosenhouse, J., 2012, Quantifying vowel characteristics in Hebrew and Arabic. Afeka-AVIOS Speech Processing Conference, 37-43.
Ansel, B. M. and Kent, R. D., 1992, Acoustic-phonetic contrasts and intelligibility in the dysarthria associated with mixed cerebral palsy. Journal of Speech and Hearing Research, 35, 296-308.
Bates, D., Maechler, M., Bolker, B. and Walker, S., 2015, Fitting linear mixed-effects models using lme4. Journal of Statistical Software, 67(1), 1-48.
Boersma, P. & Weenink, D. (2019) Praat: Doing phonetics by computer (Version 6.1.07). http://www.fon.hum.uva.nl/praat/.
Carl, M., 2018, Vowel Production in Down Syndrome-An Ultrasound Study. (Unpublished doctoral dissertation). New York, NY: The Graduate Center, City University of New York.
Carl, M., Kent, R. D., Levy, E. S. and Whalen, D. H., 2020, Vowel acoustics and speech intelligibility in young adults with Down syndrome. Journal of Speech, Language, and Hearing Research, 63(3), 674-687.
Chen, L. M., Hustad, K. C., Kent, R. D. and Lin, Y. C., 2018, Dysarthria in Mandarin-speaking children with cerebral palsy: speech subsystem profiles. Journal of Speech, Language, and Hearing Research, 61(3), 525-548.
den Ouden, Dirk-Bart, Galkina, Elena, Basilakos, Alexandra & Fridriksson, Julius (2018) Vowel formant dispersion reflects severity of apraxia of speech. Aphasiology, 32(8), 902-921.
Duffy, J. R., 2013, Motor Speech Disorders: Substrates, Differential Diagnosis, and Management. 3rd ed. (St. Louis, MO: Elsevier, Mosby).
Fletcher, A. R., Mcauliffe, M. J., Lansford, K. L. and Liss, J. M., 2017, Assessing vowel centralization in dysarthria: a comparison of methods. Journal of Speech, Language & Hearing Research, 60, 341-354.
Flipsen, P. and Lee, S., 2012, Reference data for the American English acoustic vowel space. Clinical Linguistics & Phonetics, 26(11-12), 926-933.
Fourakis, M., 1991, Tempo, stress, and vowel reduction in American English. Journal of the Acoustical Society of America, 90(4), 1816-1827.
Green, J. R., Moore, C. A., Higashikawa, M. and Steeve, R. W., 2000, The physiologic development of speech motor control: Lip and jaw coordination. Journal of Speech, Language, and Hearing Research, 43(1), 239-255.
Higgins, C. M. and Hodge, M., 2002, Vowel area and intelligibility in children with and without dysarthria. Journal of Medical Speech-Language Pathology, 10(4), 271-277.
Hsu, S. C., Jiao, Y., Mcauliffe, M. J., Berisha, V., Wu, R. M. and Levy, E. S., 2017, Acoustic and perceptual speech characteristics of native Mandarin speakers with Parkinson's disease. The Journal of the Acoustical Society of America, 141(3), EL293-EL299.
Hustad, K. C. and Cahill, M. A., 2003, Effects of presentation mode and repeated familiarization on intelligibility of dysarthric speech. American Journal of Speech-Language Pathology, 12, 2003, 198-208.
Hustad, K. C., Gorton, K. and Lee, J., 2010, Classification of speech and language profiles in 4-year-old children with cerebral palsy: a prospective preliminary study. Journal of speech, language, and hearing research, 53(6), 1496-1513.
Icht, M. and Ben-David, B. M., 2018, Sibilant production in Hebrew-speaking adults: apical versus laminal. Clinical Linguistics and Phonetics, 32(3), 193-212.
Icht, M., Zukerman, G., Hershkovich, S., Laor, T., Heled, Y., Fink, N. and Fostick, L., 2018, The ‘Morning Voice’: the effect of 24 hours of sleep deprivation on vocal parameters of young adults. Journal of Voice, 34(3), 489.e1-489.e9.
Karlsson, F. and Van Doorn, J., 2012, Vowel formant dispersion as a measure of articulation proficiency., The Journal of the Acoustical Society of America, 132(4), 2633-2641.
Kent, R. D. and Kim, Y. J., 2003, Toward an acoustic typology of motor speech disorders. Clinical Linguistics & Phonetics, 17(6), 427-445.
Kent, R. D. and Netsell, R., 1978, Articulatory abnormalities in athetoid cerebral palsy. Journal of Speech and Hearing Disorders, 43, 353-373.
Kent, R. D. and Vorperian, H. K., 2018, Static measurements of vowel formant frequencies and bandwidths: a review. Journal of Communication Disorders, 74, 74-97.
Kim, H., Hasegawa-Johnson, M. and Perlman, A., 2011, Vowel contrast and speech intelligibility in dysarthria. Folia phoniatrica et logopaedica, 63(4), 187-194.
Kim, Y. and Choi, Y., 2017, A cross-language study of acoustic predictors of speech intelligibility in individuals with Parkinson's disease. Journal of Speech, Language, and Hearing Research, 60(9), 2506-2518.
Lansford, K. and Liss, J., 2014, Vowel acoustics in dysarthria: mapping to perception. Journal of Speech, Language, and Hearing Research, 57, 68-80.
Lee, J. and Hustad, K. C., 2013, A preliminary investigation of longitudinal changes in speech production over 18 months in young children with cerebral palsy. Folia Phoniatrica et Logopaedica, 65(1), 32-39.
Lee, J., Hustad, K. C. and Weismer, G., 2014, Predicting speech intelligibility with a multiple speech subsystems approach in children with cerebral palsy. Journal of Speech, Language, and Hearing Research, 57, 1666-1678.
Lee, J., Littlejohn, M. A. and Simmons, Z., 2017, Acoustic and tongue kinematic vowel space in speakers with and without dysarthria. International Journal of Speech-Language Pathology, 19(2), 195-204.
Lenth, R., 2019, emmeans: Estimated marginal means, aka least-squares means. R package version 1.4.3.01. Available at: https://cran.r-project.org/package=emmeans.
Levy, E., 2014, Implementing two treatment approaches to childhood dysarthria., International journal of speech-language pathology, 16(4), 344-354.
Levy, E., Chang, Y. M., Ancelle, J. A. and Mcauliffe, M. J., 2017, Acoustic and perceptual consequences of speech cues for children with dysarthria. Journal of Speech Language and Hearing Research, 60, 1766-1779.
Levy, E., Leone, D., Moya-Galé, G., Hsu, S., Chen, W. and Ramig, L. O., 2016, Vowel intelligibility in children with and without dysarthria: an exploratory study. Communication Disorders Quarterly, 37(3), 171-179.
Levy, E., Moya-Galé, G., Chang, Y. M., Campanelli, L., Macleod, A. A. N., Escorial, S. and Maillart, C., 2020, Effects of speech cues in French-speaking children with dysarthria. International Journal of Language and Communication Disorders, 1-16.
Liss, J. M., Spitzer, S. M., Caviness, J. N. and Adler, C., 2002, The effects of familiarization on intelligibility and lexical segmentation in hypokinetic and ataxic dysarthria., The Journal of the Acoustical Society of America, 112(6), 3022-3030.
Liu, H.-M., Tsao, F.-M. and Kuhl, P. K., 2005, The effect of reduced vowel working space on speech intelligibility in Mandarin-speaking young adults with cerebral palsy. The Journal of the Acoustical Society of America, 117(6), 3879-3889.
Martel-Sauvageau, V., Roy, J. P., Langlois, M. and Macoir, J., 2015, Impact of the LSVT on vowel articulation and coarticulation in Parkinson's disease. Clinical Linguistics and Phonetics, 29(6), 424-440.
Mccloy, D. R., Wright, R. and Souza, P., 2014, Modeling intrinsic intelligibility variation: vowel-space size and structure. in Proceedings of Meetings on Acoustics, 1-19.
McCloy, D. (2016) phonR: Tools for phoneticians and phonologists.R package version 1.0-7. https://cran.r-project.org/web/packages/phonR/phonR.pdf.
Ménard, L., Aubin, J., Thibeault, M. and Richard, G., 2012, Measuring tongue shapes and positions with ultrasound imaging: a validation experiment using an articulatory model. Folia Phoniatrica et Logopaedica, 64(2), 64-72.
Most, T., Amir, O. and Tobin, Y., 2000, The Hebrew Vowel System: raw and normalized acoustic data. Language and Speech, 43(3), 295-308.
Mou, Z., Teng, W., Ouyang, H., Chen, Y., Liu, Y., Jiang, C., Zhang, J. and Chen, Z., 2019, Quantitative analysis of vowel production in cerebral palsy children with dysarthria. Journal of Clinical Neuroscience, 66, 77-82.
Nightingale, C., Swartz, M., Ramig, L. O. and Mcallister, T., 2020, Using crowdsourced listeners’ ratings to measure speech changes in hypokinetic dysarthria: a proof-of-concept study. American Journal of Speech-Language Pathology, 29, 873-882.
Nip, I. S. B., Arias, C. R., Morita, K. and Richardson, H., 2017, Initial observations of lingual movement characteristics of children with cerebral palsy. Journal of Speech, Language & Hearing Research, 60, 1780-1790.
Pennington, L., Smallman, C. and Farrier, F., 2006, Intensive dysarthria therapy for older children with cerebral palsy: findings from six cases., Child Language Teaching & Therapy, 22(3), 255-273.
Peterson, G. and Barney and H., 1952, Control methods used in the study of vowels. The Journal of the Acoustical Society of America, 24(2), 175-184.
Pinto, S., Chan, A., Guimarães, I., Rothe-Neves, R. and Sadat, J., 2017, A cross-linguistic perspective to the study of dysarthria in Parkinson's disease. Journal of Phonetics, 64, 156-167.
R Core Team, 2020, R: A Language and Environment for Statistical Computing. (Vienna, Austria: R Foundation for Statistical Computing. URL https://www.r-project.org/.).
Rosin, D. and Yakir, P., 2000, Pictures for examining articulation and naming of Hebrew-speaking children in Israel. (Rehovot, Israel).
Sapir, S., Ramig, L. O., Spielman, J. L. and Fox, C., 2010, Formant Centralization Ratio : a proposal for a new acoustic measure of dysarthric speech. Journal of Speech, Language, and Hearing Research, 53, 114-125.
Sapir, S., Spielman, J. L., Ramig, L. O., Story, B. H. and Fox, C., 2007, Effects of intensive voice treatment (the Lee Silverman Voice Treatment [LSVT]) on vowel articulation in dysarthric individuals with idiopathic Parkinson disease: acoustic and perceptual findings. Journal of Speech, Language, and Hearing Research, 50(4), 899-912.
Strange, W., Weber, A., Levy, E. S., Shafiro, V., Hisagi, M. and Nishi, K., 2007, Acoustic variability within and across German, French, and American English vowels: phonetic context effects. The Journal of the Acoustical Society of America, 122(2), 1111-1129.
Tjaden, K. and Wilding, G. E., 2004, Rate and loudness manipulations in dysarthria: acoustic and perceptual findings. Journal of Speech Language and Hearing Research, 47(4), 766-783.
Traunmüller, H., 1990, Analytical expressions for the tonotopic sensory scale. Journal of the Acoustical Society of America, 88(1), 97-100.
Turner, G. S., Tjaden, K. and Weismer, G., 1995, The influence of speaking rate on vowel space and speech intelligibility for individuals with amyotrophic lateral sclerosis. Journal of Speech Language and Hearing Research, 38(5), 1001-1013.
Vorperian, H. K. and Kent, R. D., 2007, Vowel Acoustic Space Development in children: a synthesis of acoustic and Anatomic Data. Journal of Speech, Language, and Hearing Research, 50, 1510-1545.

Keywords: acoustic vowel analysis; cerebral palsy; developmental dysarthria; speech intelligibility; vowel space

Date Created: 20210201 Date Completed: 20211025 Latest Revision: 20211025

20250114

10.1111/1460-6984.12598

33522087