Ultrasound and acoustic analysis of sibilant fricatives in preadolescents and adults

This study describes the production of sibilant fricatives /s/ and /?/ , comparing Scottish English speaking preadolescent children with adults. The materials were the sequences /Ca/ and /Ci/ produced by 15 adults and 15 children aged between 10 and 12 years old. Quantitative analyses were carried out on both spectral information and on ultrasound imaging data on tongue shape, taken from nine successive time points during the fricative. The two groups of speakers were very similar to each other in the articulatory and acoustic characteristics distinguishing the two fricatives. Age-related differences in the fricative centroid measure occurred at consonant-vowel boundaries, with lower values in the preadolescents. Within-speaker variability was mostly similar across age groups, with the exception of the fricative centroid for /?/ , which was significantly more variable in preadolescents than in adults. Throughout the consonant duration, both groups consistently differentiated between the two consonants in both the fricative centroid and in one measure of tongue shape. 2016 Acoustical Society of America.casl139pub4373pub

Insights from ultrasound : enhancing our understanding of clinical phonetics

This is the editorial from the journal "Clinical Linguistics and Phonetics", from a Special Issue entitled "Insights from Ultrasound". \ud \ud The timing of this special issue was in part inspired by the 6th Ultrafest conference in Edinburgh in 2013, a meeting in which phoneticians, clinicians and engineers working in ultrasound tongue imaging came together. We invited contributions from these and other experts in the field working with ultrasound as a tool for investigating clinical populations; as a biofeedback device in speech therapy; or as a tool for investigating typical speech production, with a view to informing investigations of clinical populations

Strategies in the acquisition of segments and syllables in Russian-speaking children.

This study investigates the phonological development of ten children reared in Russian-speaking homes, from the emergence of first words to the age of three years two months. The paper consists of three parts: acquisition of phonemes and phonological oppositions; acoustic analysis of the consonantal opposition in palatalization emerging in children; acquisition of syllable structure of words and different syllable omission patterns. The focus is made on individual strategies adopted by different children. Some data challenge the literature claim about the acquisition of labials before other consonants and the claim about 'trochaic bias' in early word production.casl2pub2176pub

An EPG and ultrasound study of lingual coarticulation in vowel-consonant sequences

While EPG registers the location and amount of tongue-palate contact, ultrasound can capture most of the tongue contour. Previous studies have not systematically quantified lingual coarticulation using EPG and ultrasound simultaneously. This study used both techniques for analysing vowel-consonant coarticulatory effects. Four speakers of Scottish English produced /VC/ sequences with the consonants /p, f, t, s, l, r, k/ and the vowels /a, i/. The difference between each consonant in the two vowel contexts was computed using an EPG measure and an ultrasound measure. Additionally, temporal coarticulation was analysed, using EPG data. A significant positive correlation was observed between the two measures, with labial consonants, followed by /r/, having the highest values. The two techniques also provided complementary data on lingual coarticulation. The velar stop was more coarticulated on the EPG measure than on the ultrasound measure, because EPG registered a shift in closure location across vowel contexts, while ultrasound captured the close proximity of the tongue root across the vowel contexts. The sibilant was more coarticulated on the ultrasound measure than on the EPG measure, because ultrasound, unlike EPG, registered vowel-dependent difference in the tongue root. Combined EPG and ultrasound data would be useful in future studies of coarticulation.casl[1]. P. Bacsfalvi, B.M. Bernhardt, & B. Gick. Electropalatography and ultrasound in vowel remediation for adolescents with hearing impairment. Advances in Speech-Language Pathology, 9, 36-45, 2007. [2] L. Davidson. Coarticulation in contrastive Russian stop sequences. In Proceedings of the 16th International Congress of Phonetic Sciences, 417-420, 2007. [3]. E. Farnetani. V-C-V lingual coarticulation and its spatio-temporal domain. In W.J. Hardcastle and A. Marchal (Eds), Speech Production and Speech Modelling. Kluwer Academic, The Netherlands, 93-110, 1990. [4]. F. Gibbon and K. Nicolaidis. Palatography. In W. Hardcastle & N. Hewlett (Eds), Coarticulation: Theory, Data and Techniques. Cambridge University Press, Cambridge, 229-245, 1999. [5]. M. Gordon, R. Kennedy, D. Archangeli, & A. Baker. Distributed effects in coarticulation: an ultrasound study. [Oral presentation at Ultrafest IV, New York, USA, 28- 29 September 2007.] [6]. J.S. Perkell. Physiology of Speech Production: Results and Implications of a Quantitative Cineradiographic Study. MIT Press, Cambridge, MA, 1969. [7]. J. Scobbie, S. Wood, & A. Wrench. Advances in EPG for treatment and research: an illustrative case study. Clinical Linguistics and Phonetics, 18, 373-389, 2004. [8]. M. Stone. A guide to analyzing tongue motion from ultrasound images. Clinical Linguistics and Phonetics, 19, 455-502, 2005. [9]. M. Stone, A. Faber, L.J. Raphael, & T.H. Shawker. Cross-sectional tongue shape and linguopalatal contact patterns in [s], [], and [l]. Journal of Phonetics, 20, 253- 270, 1992. [10]. M. Stone & A. Lundberg. Three-dimensional tongue surface shapes of English consonants and vowels. Journal of the Acoustical Society of America, 99, 3728-3737, 1996. [11]. M. Stone & E. Vatikiotis-Bateson. Trade-offs in tongue, jaw, and palate contributions to speech production. Journal of Phonetics, 23, 81-100, 1995. [12]. Y. Vazquez Alvarez and N. Hewlett. The trough effect: an ultrasound study. Phonetica, 65:105-121, 2007. [13]. S. Wodzinski and S. Frisch. Ultrasound study of velar-vowel coarticulation. Journal of the Acoustical Society of America, 120:3373-3374, 2006. [14]. A. Wrench. Articulate Assistant Advanced: ultrasound module. [Oral presentation at Ultrafest IV, New York, USA, 28-29 September 2007.] [15]. N. Zharkova. Quantification of coarticulatory effects in several Scottish English phonemes using ultrasound. QMU Speech Science Research Centre Working Papers, WP-13, 2007pub251pu

An ultrasound study of the development of lingual coarticulation during childhood

This is the peer-reviewed but unedited manuscript version of the following article: Zharkova, N. (2018) An ultrasound study of the development of lingual coarticulation during childhood. Phonetica, 75 (3), pp. 245-271. https://doi.org/10.1159/000485802. The final, published version is available at http://www.karger.com/?doi=10.1159/000485802Background/Aims. There is growing evidence that coarticulation development is protracted and segment-specific, and yet very little information is available on the changes in the extent of coarticulation across different phonemes throughout childhood. This study describes lingual coarticulatory patterns in six age groups of Scottish English speaking children between three and thirteen years old. Methods. Vowel-on-consonant anticipatory coarticulation was analysed using ultrasound imaging data on tongue shape from four consonants that differ in the degree of constraint, i.e., the extent of articulatory demand, on the tongue. Results. Consonant-specific age-related patterns are reported, with consonants that have more demands on the tongue reaching adolescent-like levels of coarticulation in older age groups. Within-speaker variability in tongue shape decreases with increasing age. Conclusion. Reduced coarticulation in the youngest age group may be due to insufficient tongue differentiation. Immature patterns for lingual consonants in 5-to-11-year-olds are explained by the goal of producing the consonant target overriding the goal of coarticulating the consonant with the following vowel.casl75pub5328pub

Adult speakers' tongue-palate contact patterns for bilabial stops within complex clusters

Previous studies using Electropalatography (EPG) have shown that individuals with speech disorders sometimes produce articulation errors that affect bilabial targets, but currently there is limited normative data available. In this study, EPG and acoustic data were recorded during complex word final /sps/ clusters spoken by 20 normal adults. A total contact (TC) index measured amount of tongue-palate contact during clusters in words such as 'crisps'. Bilabial closure was inferred from the acoustic signal. The TC profiles indicated that normal adults hold their tongues in a steady /s/-like position throughout the cluster; most speakers (85%, n=17) had no significant difference in TC values during bilabial closure compared to flanking fricatives. The results are interpreted as showing that normal speakers produce double bilabial-alveolar articulations for /p/ in these clusters. Although steady state TC profiles were typical of the group, absolute TC values varied considerably between speakers, with some speakers having up to three times more contact than others. These findings add to the knowledge about normal articulation, and will help to improve diagnosis and treatment of individuals with speech disorders

Tutorial: Speech Assessment for Multilingual Children Who Do Not Speak the Same Language(s) as the Speech-Language Pathologist

Purpose: The aim of this tutorial is to support speech language pathologists (SLPs) undertaking assessments of multilingual children with suspected speech sound disorders, particularly children who speak languages that are not shared with their SLP. Method: The tutorial was written by the International Expert Panel on Multilingual Children's Speech, which comprises 46 researchers (SLPs, linguists, phoneticians, and speech scientists) who have worked in 43 countries and used 27 languages in professional practice. Seventeen panel members met for a 1-day workshop to identify key points for inclusion in the tutorial, 26 panel members contributed to writing this tutorial, and 34 members contributed to revising this tutorial online (some members contributed tomore than 1 task). Results: This tutorial draws on international research evidence and professional expertise to provide a comprehensive overview of working with multilingual children with suspected speech sound disorders. This overview addresses referral, case history, assessment, analysis, diagnosis, and goal setting and the SLP's cultural competence and preparation for working with interpreters and multicultural support workers and dealing with organizational and government barriers to and facilitators of culturally competent practice. Conclusion: The issues raised in this tutorial are applied in a hypothetical case study of an English-speaking SLP's assessment of a multilingual Cantonese-and English-speaking 4-year-old boy. Resources are listed throughout the tutorial. 2017 The Authors.The development of this tutorial was supported by an Australian Research Council Future Fellowship (FT0990588) “Speaking My Languages: International Speech Acquisition in Australia” awarded to Sharynne McLeod.casl26pub4836pub

Using ultrasound tongue imaging to identify covert contrasts in children's speech

Special Issue on Covert ContrastsUltrasound tongue imaging has become a promising technique for detecting covert contrasts, due to the developments in data analysis methods that allow for processing information on tongue shape from young children. An important feature concerning analyses of ultrasound data from children who are likely to produce covert contrasts is that the data are likely to be collected without head-to-transducer stabilisation, due to the speakers' age. This article is a review of the existing methods applicable in analysing data from non-stabilised recordings. The article describes some of the challenges of ultrasound data collection from children, and analysing these data, as well as possible ways to address those challenges. Additionally, there are examples from typical and disordered productions featuring covert contrasts, with illustrations of quantifying differences in tongue shape between target speech sounds.caslAbakarova, D., Iskarous, K., Robertus, E., Ries, J., Tiede, M., & Noiray, A. (2015). Development of coarticulation in German children: Mutual information as a measure of coarticulation and invariance. Poster at Ultrafest VII, 8-10 December 2015, University of Hong Kong, Hong Kong. Aubin, J., & Mnard, L. (2006). Compensation for a labial perturbation: An acoustic and articulatory study of child and adult French speakers. In H. C. Yehia, D. Demolin, & R. Laboissire (Eds.), Proceedings of the 7th international seminar on speech production (pp. 209-216). Ubatuba, Brazil. Bacsfalvi, P., & Bernhardt, B. M. (2011). Long-term outcomes of speech therapy for seven adolescents with visual feedback technologies: Ultrasound and electropalatography. Clinical Linguistics & Phonetics, 25, 1034-1043. 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Lingual Coarticulation in Preadolescents and Adults: An Ultrasound Study. ESRC End of Award Report, RES-000-22-4075

SwindonWhen people combine sounds to make words, there is overlap in the tongue movements involved in articulating individual sounds, referred to as lingual coarticulation. For example, in adult speech, tongue positions at mid-consonant, in the words she- and shah-, differ because of the influence of the following vowel. The research team's earlier work showed that young children differed from adults in the extent of vowel-on-consonant coarticulation. In this project, for the first time, a quantitative analysis of the dynamics of tongue movements was performed. The project used high-speed ultrasound to measure lingual coarticulation in the syllables she-, shah-, sea- and 'Sah', comparing preadolescent children and adults, fifteen speakers in each age group. In both age groups and both consonants, the tongue position at mid-consonant was affected by the identity of the following vowel. There was no significant effect of age on the size of the vowel-related difference in tongue posture, nor on within-speaker variability in tongue placement. Age-related differences were observed in the onset of coarticulation. While in the adults, the vowel effect was present throughout the consonant for both consonants, in preadolescents the effect was apparent later into the first half of the consonant. The results of the study suggest a near-adult-like achievement in the development of lingual control by preadolescents, with respect to the coarticulation of fricative-vowel sequences. However age-related differences in timing may indicate that preadolescents have still to gain the extent of forward planning in speech production which is possible for a typical adult.caslpub3341pu

An ultrasound study of lingual coarticulation in children and adults

There have been a number of studies which compared coarticulatory patterns in children and adults, but these studies have produced conflicting results, particularly with respect to anticipatory lingual coarticulation. This study used articulatory measures derived from ultrasound imaging, in order to establish any differences between child and adult coarticulatory patterns, and to quantify the degree of variability in children's and adults' productions. The participants were four adults and four normally developing children aged 6 to 9 years, all speakers of Standard Scottish English. The data were the syllables /i/, /u/ and /a/, in the carrier phrase It's a -_ Pam- (ten repetitions). Synchronised ultrasound and acoustic data were recorded using the Queen Margaret University ultrasound system. Extent of consonantal coarticulation and within-speaker variation in child and adult productions were compared according to a new ultrasound-based measure of coarticulation. A significantly greater amount of anticipatory lingual coarticulation was found in children than in adults. Much within-group variability was observed, in both age groups. Within-speaker variability was significantly greater in children than in adults. These results are in agreement with some previous studies. Possible reasons are discussed for some of the contradictions in the literature on child and adult coarticulation.casl[1]. E.H. Buder. Experimental phonology with acoustic phonetic methods: formant measures from child speech. In B. Bernhardt, J. Gilbert, & D. Ingram (Eds), Proceedings of the UBC International Conference on Phonological Acquisition. Cascadilla Press, Somerville, 254-265, 1996. [2]. W.F. Katz & S. Bharadwaj. Coarticulation in fricativevowel syllables produced by children and adults: a preliminary report. Clinical Linguistics and Phonetics, 15:139-143, 2001. [3]. W.F. Katz, C. Kripke, & P. Tallal. Anticipatory coarticulation in the speech of adults and young children: acoustic, perceptual, and video data. Journal of Speech and Hearing Research, 34:1222-1232, 1991. [4]. R.D. Kent, R.D. The segmental organization of speech. In P.F. MacNeilage (Ed.), The Production of Speech. Springer-Verlag, New York, 57-89, 1983. [5]. L. Nijland, B. Maassen, S. Van der Meulen, F. Gabriels, F.W. Kraaimaat, & R. Schreuder. Coarticulation patterns in children with developmental apraxia of speech. Clinical Linguistics and Phonetics, 16:461-483, 2002. [6]. S. Nittrouer, M. Studdert-Kennedy, & R.S. McGowan. The emergence of phonetic segments: evidence from the spectral structure of fricative-vowel syllables spoken by children and adults. Journal of Speech and Hearing Research, 32:120-132, 1989. [7]. S. Nittrouer, M. Studdert-Kennedy, & S.T. Neely. How children learn to organize their speech gestures: further evidence from fricative-vowel syllables. Journal of Speech and Hearing Research, 39:379-389, 1996. [8]. J. Sankaranarayanan, H. Samet, & A. Varshney. A fast all nearest neighbour algorithm for applications involving large point-clouds. Computers & Graphics, 31:157-174, 2007. [9]. J.A. Sereno, A.R. Baum, G. Cameron Marean, & P. Lieberman. Acoustic analyses and perceptual data on anticipatory labial coarticulation in adults and children. Journal of the Acoustical Society of America, 81:512-519, 1987. [10]. K.A. Siren & K.A. Wilcox. Effects of lexical meaning and practiced productions on coarticulation in children's and adults' speech. Journal of Speech and Hearing Research, 38:351-359, 1995. [11]. H.M. Sussman, K.A. Hoemeke, & H.A. McCaffrey. Locus equations as an index of coarticulation for place of articulation distinctions in children. Journal of Speech and Hearing Research, 35:769-781, 1992. [12]. A.E. Thompson & T.J. Hixon. Nasal air flow during normal speech production. Cleft Palate Journal, 16:412- 420, 1979. [13]. Y. Vazquez Alvarez and N. Hewlett. The trough effect: an ultrasound study. Phonetica, 65:105-121, 2007. [14]. N. Zharkova. Quantification of coarticulatory effects in several Scottish English phonemes using ultrasound. QMU Speech Science Research Centre Working Papers, WP-13, 2007pub243pu