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

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    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.
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    Using ultrasound tongue imaging to identify covert contrasts in children's speech
    (2017) Zharkova, Natalia; Gibbon, Fiona; Lee, Alice
    Ultrasound 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.