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Permanent URI for this collectionhttps://eresearch.qmu.ac.uk/handle/20.500.12289/22
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Item 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, PerttiPrevious 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.Item 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, PerttiChildren 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.Item The dynamics of voiceless sibilant fricative production in children between 7 and 13 years old: An ultrasound and acoustic study(Acoustical Society of America (ASA), 2018-09-19) Zharkova, Natalia; Hardcastle, William J.; Gibbon, Fiona E.This study reports on dynamic tongue shape and spectral characteristics of sibilant fricatives /s/ and /ʃ/ in Scottish English speaking children aged between 7 and 13 years old. The sequences /əCa/ and /əCi/ were produced by 40 children, with ten participants in each age group, and two-year intervals between successive groups. Productions of the same sequences by ten adults were used for comparison with the children's data. Quantitative dynamic analyses were carried out on spectral information and on ultrasound imaging data on tongue shape. All age groups differentiated between the two consonants in the fricative centroid and in tongue shape. Vowel-on-consonant effects showed consonant-specific patterns across age groups without a consistent increase or decrease in the extent of coarticulation with increasing age. The extent of discriminability between the two fricatives increased with age on both acoustic and articulatory measures. Younger speakers were generally more variable than older speakers. Complementary findings from the centroid and tongue shape measures suggest that age-related differences are due to the ongoing maturation of controlling the tongue in coordination with other articulators, particularly the jaw, throughout childhood.Item Using ultrasound to quantify tongue shape and movement characteristics(Allen Press Incorporated, 2013-01) Zharkova, NataliaObjective: 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.Item Using ultrasound tongue imaging to identify covert contrasts in children's speech(2017) Zharkova, Natalia; Gibbon, Fiona; Lee, AliceUltrasound 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.