CASL

Permanent URI for this collectionhttps://eresearch.qmu.ac.uk/handle/20.500.12289/22

Browse

Search Results

Now showing 1 - 10 of 25

The impact of real-time articulatory information on phonetic transcription: Ultrasound-aided transcription in cleft lip and palate speech
(Karger, 2019-05-24) Cleland, Joanne; Lloyd, Susan; Campbell, Linsay; Crampin, Lisa; Palo, Pertti; Sugden, Eleanor; Wrench, Alan A.; Zharkova, Natalia
Objective: This study investigated whether adding an additional modality, namely ultrasound tongue imaging, to perception-based phonetic transcription impacted on the identification of compensatory articulations and on interrater reliability. Patients and Methods: Thirty-nine English-speaking children aged 3 to 12 with cleft lip and palate (CLP) were recorded producing repetitions of /aCa/ for all places of articulation with simultaneous audio and probe-stabilised ultrasound. Three types of transcriptions were performed: 1. Descriptive observations from the live ultrasound by the clinician recording the data; 2. Ultrasound-aided transcription by two ultrasound-trained clinicians; and 3. Traditional phonetic transcription by two CLP specialists from audio recording. We compared the number of consonants identified as in error by each transcriber and then classified errors into eight different subcategories. Results: Both the ultrasound-aided and traditional transcriptions yielded similar error-detection rates, however these were significantly higher than the observations recorded live in the clinic. Interrater reliability for the ultrasound transcribers was substantial (k=0.65), compared to moderate (k=0.47) for the traditional transcribers. Ultrasound-aided transcribers were more likely to identify covert errors such as double articulations and retroflexion than the audio-only transcribers. Conclusion: Ultrasound-tongue imaging is a useful complement to traditional phonetic transcription for CLP speech.
Visualising speech: Identification of atypical tongue-shape patterns in the speech of children with cleft lip and palate using ultrasound technology
(NHS Greater Glasgow & Clyde and University of Strathclyde, Glasgow, 2018) Lloyd, Susan; Cleland, Joanne; Crampin, Lisa; Campbell, Linsay; Zharkova, Natalia; Palo, Pertti
Previous research by Gibbon (2004) shows that at least 8 distinct error types can be identified in the speech of people with cleft lip and palate (CLP) using electropalatography (EPG), a technique which measures tongue-palate contact. However, EPG is expensive and logistically difficult. In contrast, ultrasound is cheaper and arguably better equipped to image the posterior articulations (such as pharyngeals) which are common in CLP. A key aim of this project is to determine whether the eight error types made visible with EPG in CLP speech described by Gibbon (2004) can be also be identified with ultrasound. This paper will present the first results from a larger study developing a qualitative and quantitative ultrasound speech assessment protocol. Data from the first 20 children aged 3 to 18 with CLP will be presented. Data are spoken materials from the CLEFTNET protocol. We will present a recording format compatible with CAPS-A to record initial observations from the live ultrasound (e.g. double articulations, pharyngeal stops). Two Speech and Language Therapists analysed the data independently to identify error types. Results suggest that all of the error types, for example fronted placement and double articulations can be identified using ultrasound, but this is challenging in real-time. Ongoing work involves quantitative analysis of error types using articulatory measures.
Visualising speech: Using ultrasound visual biofeedback to diagnose and treat speech disorders in children with cleft lip and palate
(NHS Greater Glasgow & Clyde and University of Strathclyde, Glasgow, 2017-09) Cleland, Joanne; Crampin, Lisa; Zharkova, Natalia; Wrench, Alan A.; Lloyd, Susan; Palo, Pertti
Children with cleft lip and palate (CLP) often continue to have problems producing clear speech long after the clefts have been surgically repaired, leading to educational and social disadvantage. Speech is of key importance in CLP from both a quality of life and surgical outcome perspective, yet assessment relies on subjective perceptual methods, with speech and language therapists (SLTs) listening to speech and transcribing errors. This is problematic because perception-based phonetic transcription is well known to be highly unreliable(Howard & Lohmander, 2011) especially in CLP, where the range of error types is arguably far greater than for other speech sound disorders. Moreover,CLP speech is known to be vulnerable to imperceptible error types, such as double articulations which can only be understood with instrumental techniques such as ultrasound tongue imaging (UTI). Incorrect transcription of these errors can result in misdiagnosis and subsequent inappropriate intervention which can lead to speech errors becoming deeply ingrained.
Quantifying lingual coarticulation using ultrasound imaging data collected with and without head stabilisation
(2015-04-01) Zharkova, Natalia; Gibbon, Fiona; Hardcastle, William J.
Previous studies reporting the use of ultrasound tongue imaging with clinical populations have generally provided qualitative information on tongue movement. Meaningful quantitative measures for use in the clinic typically require the speaker's head to be stabilised in relation to a transducer, which may be uncomfortable, and unsuitable for young children. The objective of this study was to explore the applicability of quantitative measurements of stabilisation-free tongue movement data, by comparing ultrasound data collected from 10 adolescents, with and without head stabilisation. Several measures of tongue shape were used to quantify coarticulatory influence from two contrasting vowels on four different consonants. Only one of the measures was completely unaffected by the stabilisation condition for all the consonants. The study also reported cross-consonant differences in vowel-related coarticulatory effects. The implications of the findings for the theory of coarticulation and for potential applications of stabilisation-free tongue curve measurements in clinical studies are discussed.
Development of lingual motor control in children and adolescents
(University of Glasgow: Glasgow, 2015-08-10) Zharkova, Natalia; Hardcastle, William J.; Gibbon, Fiona; Lickley, Robin
An important insight into speech motor control development can be gained from analysing coarticulation. Despite a growing number of acoustic and articulatory studies of lingual coarticulation in children, there are conflicting opinions on how the extent of coarticulation changes during childhood. There is also increasing evidence that age-related patterns vary depending on speech sounds involved. The present study employed ultrasound tongue imaging to compare anticipatory V-on-C coarticulation in 13-year-old adolescents and 5-year-old children, using the consonants /p/ and /t/, which differ in the amount of lingual coarticulation in adult speech. For /p/, the two groups had a similar amount of coarticulation. For /t/, both groups had a vowel effect on the extent of tongue bunching, while only adolescents had an effect on the location of tongue bunching. Token-to-token variability in absolute tongue position was larger in the 5-year-olds. We discuss the findings in relation to previous studies and existing theories
Using ultrasound to quantify tongue shape and movement characteristics
(Allen Press Incorporated, 2013-01) Zharkova, Natalia
Objective: Previous experimental studies have demonstrated abnormal lingual articulatory patterns characterising cleft palate speech. Most articulatory information to date has been collected using electropalatography, which records the location and size of tongue-palate contact, but not the tongue shape. The latter type of data can be provided by ultrasound. The present paper aims to describe ultrasound tongue imaging as a potential tool for quantitative analysis of tongue function in speakers with cleft palate. A description of the ultrasound technique as applied to analysing tongue movements is given, followed by the requirements for quantitative analysis. Several measures are described, and example calculations are provided. Measures: Two measures are aimed to quantify overuse of tongue dorsum in cleft palate articulations. Crucially for potential clinical applications, these measures do not require head to transducer stabilisation, because both are based on a single tongue curve. The other three measures compare sets of tongue curves, with the aim to quantify the dynamics of tongue displacement, token-to-token variability in tongue position, and the extent of separation between tongue curves for different speech sounds. Conclusions: All measures can be used to compare tongue function in speakers with cleft palate before and after therapy, as well as to assess their performance against that in typical speakers, and to help in selecting more effective treatments.
An ultrasound study of lingual coarticulation in /sV/ syllables produced by adults and typically developing children
(Cambridge University Press, 2012-08-02) Zharkova, Natalia; Hewlett, Nigel; Hardcastle, William J.; Economic and Social Research Council
According to the Degree of Articulatory Constraint model of lingual coarticulation, the consonant /s/ has some scope for tongue adaptation to neighbouring vowels, since the tongue dorsum is not directly involved in constriction formation for this consonant. The present study aimed to establish whether the tongue shape for /s/ in consonant-vowel syllables was influenced by the nature of the following vowel, in Scottish-English-speaking children and adults. Ultrasound tongue imaging was used to establish the presence or otherwise of a vowel effect at the consonant midpoint, by measuring differences between the consonant tongue contours in different vowel environments. In adults, the vowel pairs /a/-/i/, /a/-/u/ and /i/-/u/ exerted significant coarticulatory effects on /s/. In children, no significant effects on /s/ were observed. Greater within-speaker variability in lingual articulation was found in children than in adults. The reduced ability of children to anticipate the tongue configuration of a following vowel whilst simultaneously implementing an initial /s/ sound could be explained by lesser differential control of tip/blade and tongue body.
Measuring lingual coarticulation from midsagittal tongue contours: Description and example calculations using English /t/ and //
(2009-04) Zharkova, Natalia; Hewlett, Nigel
The purpose of this study was to test the feasibility of a protocol for measuring coarticulation using tongue surface outline data derived from ultrasound imaging. Ultrasound and acoustic data were collected from three speakers of Southern British English while they repeated a list of three sentences 15 times. Tongue surface outlines for the consonant /t/ in /a{script}ta{script}/ (in ...Ma tasked...) were compared with those for the /t/ in /iti/ (in ... Leigh teased...) and tongue surface outlines for the vowel /a{script}/ in /a{script}ka{script}/ (in ... Ma cast...) were compared with those in /a{script}ta{script}/. Nearest neighbour distance calculations were used for the comparison of tongue surface outlines. Mean distance in midsagittal tongue surface outline between tokens of the same phoneme across two different environments was taken as a measure of the phoneme's susceptibility to environmental influence. The calculations show that the tongue contour during /t/ adapts to the influence of the neighbouring vowels approximately three times more than the tongue contour during /a{script}/ adapts to the influence of the neighbouring consonants. The applicability of the measure proposed in this paper to future speech research using ultrasound and other articulatory techniques is discussed. 2008 Elsevier Ltd. All rights reserved.
A normative-speaker validation study of two indices developed to quantify tongue dorsum activity from midsagittal tongue shapes
(2013-07) Zharkova, Natalia
This study reported adult scores on two measures of tongue shape, based on midsagittal tongue shape data from ultrasound imaging. One of the measures quantified the extent of tongue dorsum excursion, and the other measure represented the place of maximal excursion. Data from six adult speakers of Scottish Standard English without speech disorders were analyzed. The stimuli included a range of consonants in consonant-vowel sequences, with the vowels/a/and/i/. The measures reliably distinguished between articulations with and without tongue dorsum excursion, and produced robust results on lingual coarticulation of the consonants. The reported data can be used as a starting point for collecting more typical data and for analyzing disordered speech. The measurements do not require head-to-transducer stabilization. Possible applications of the measures include studying tongue dorsum overuse in people with cleft palate, and typical and disordered development of coarticulation. 2013 Informa UK Ltd.
Editorial: Insights from ultrasound: Enhancing our understanding of clinical phonetics
(Taylor & Francis, 2016-02-22) Cleland, Joanne; Scobbie, James M.; Zharkova, Natalia
This is the editorial from the journal Clinical Linguistics and Phonetics, from a Special Issue entitled Insights from Ultrasound. 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.

CASL

Browse

Filters

Settings

Sort By

Results per page

Search Results