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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 The use of electropalatography in the treatment of speech disorders in children with Down Syndrome: a randomised controlled trial(2018-07-24) Wood, Sara; Timmins, Claire; Wishart, Jennifer; Hardcastle, William J.; Cleland, JoanneBackground: Electropalatography (EPG) records details of the location and timing of tongue contacts with the hard palate during speech. It has been effective in treating articulation disorders that have failed to respond to conventional therapy approaches but, until now, its use with children and adolescents with intellectual/learning disabilities and speech disorders has been limited. Aims: This study aimed to evaluate the usefulness of EPG in the treatment of speech production difficulties in children and adolescents with Down syndrome (DS) aged 8-18 years. Methods: Twenty-seven children with DS were assessed on a range of cognitive and speech and language measures and underwent additional EPG assessment. Participants were randomly allocated to one of three age-matched groups receiving either EPG therapy, EPG-informed conventional therapy or ‘treatment as usual’ over a 12 week period. The speech of all children was assessed before therapy using the Diagnostic Evaluation of Articulation and Phonology (DEAP: Dodd et al. 2002) and re-assessed immediately post- and 3- and 6-month post-intervention to measure percent consonants correct (PCC). EPG recordings were made of the DEAP assessment items at all time-points. Percent intelligibility was also calculated using the Children’s Speech Intelligibility Measure (CSIM: Wilcox and Morris 1999). Results: Gains in accuracy of production immediately post-therapy, as measured by PCC, were seen for all groups. Reassessment at 3- and 6-month post-therapy revealed that those who had received therapy based directly on EPG visual feedback were more likely to maintain and improve on these gains compared to the other groups. Statistical testing showed significant differences between groups in DEAP scores across time-points although the majority did not survive post hoc evaluation. Intelligibility across time-points, as measured by CSIM, was also highly variable within and between the three groups, but despite significant correlations between DEAP and CSIM at all time-points, no statistically significant group differences emerged. Conclusions and implications: EPG was an effective intervention tool for improving speech production in many participants. This may be because it capitalizes on the relative strength of visual over auditory processing in this client group. The findings would seem to warrant an increased focus on addressing speech production difficulties in current therapyItem Speech Production in Down Syndrome(2009) Timmins, Claire; Cleland, Joanne; Rodger, Rebecca; Wishart, Jennifer; Wood, Sara; Hardcastle, William J.Item Widening access to electropalatography for children with persistent sound system disorders.(American Speech-Language-Hearing Association, 1999-11) Gibbon, Fiona; Stewart, Fiona; Hardcastle, William J.Previous studies have demonstrated the value of using electropalatography (EPG) to assess, diagnose, and treat persistent sound system disorders in children. However, the application of EPG research has been limited in clinical contexts because most speech-language pathologists do not have access to the technique. This article provides an overview of recent EPG research on persistent sound system disorders and describes a network that has been established to widen access to EPG. The use of EPG via the network is illustrated in the case description of an 8-year-old boy, Robbie, who presented with a persisting speech disorder. The network was used because the clinician treating Robbie did not have an EPG. The main perceptual feature of Robbie's speech before EPG treatment was the deviant phonological process of backing /t/ and /d/ targets to velar place of articulation. EPG was used to assess articulatory patterns before treatment, to provide visual feedback as part of a treatment program, and to record changes in tongue-palate contact patterns as treatment progressed. Robbie achieved normal /t/ and /d/ articulatory patterns after treatment and was subsequently discharged. Factors that could have contributed to the successful outcome in this case are discussed, and areas requiring further research are identified.Item Relationship between speech, oromotor, language and cognitive abilities in children with Down's syndrome(2010-01) Cleland, Joanne; Wood, Sara; Hardcastle, William J.; Wishart, Jennifer; Timmins, ClaireBackground: Children and young people with Down's syndrome present with deficits in expressive speech and language, accompanied by strengths in vocabulary comprehension compared with non-verbal mental age. Intelligibility is particularly low, but whether speech is delayed or disordered is a controversial topic. Most studies suggest a delay, but no studies explore the relationship between cognitive or language skills and intelligibility. Aims: This study sought to determine whether severity of speech disorder correlates with language and cognitive level and to classify the types of errors, developmental or non-developmental, that occur in the speech of children and adolescents with Down's syndrome. Methods & Procedures: Fifteen children and adolescents with Down's syndrome (aged 9-18 years) were recruited. Participants completed a battery of standardized speech, language and cognitive assessments. The phonology assessment was subject to phonological and phonetic analyses. Results from each test were correlated to determine relationships. Outcome & Results: Individuals with Down's syndrome present with deficits in receptive and expressive language that are not wholly accounted for by their cognitive delay. Receptive vocabulary is a strength in comparison with expressive and receptive language skills, but it was unclear from the findings whether it is more advanced compared with non-verbal cognitive skills. The majority of speech errors were developmental in nature, but all of the children with Down's syndrome showed at least one atypical or non-developmental speech error. Conclusions & Implications: Children with Down's syndrome present with speech disorders characterized by atypical, and often unusual, errors alongside many developmental errors. A lack of correlation between speech and cognition or language measures suggests that the speech disorder in Down's syndrome is not simply due to cognitive delay. Better differential diagnosis of speech disorders in Down's syndrome is required, allowing interventions to target the specific disorder in each individual.Item 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.Item Variability in fricative production of young people with Down's syndrome : an EPG analysis(2007-08) Timmins, Claire; Hardcastle, William J.; Wood, Sara; McCann, Joanne; Wishart, Jennifer; Acknowledgements: MRC grant no. G0401388Speech production in Down's syndrome is highly variable, with particular problems arising from complex articulations such as fricatives. In this paper, EPG analysis is used to study the variation in the production of the fricatives /s/ and /sh/ in 6 young people with Down's syndrome. The variability of these productions is compared with information from the Robbins and Klee Oral/Speech Motor Control Protocol.Item Development of lingual motor control in children and adolescents(University of Glasgow: Glasgow, 2015-08-10) Zharkova, Natalia; Hardcastle, William J.; Gibbon, Fiona; Lickley, RobinAn 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 theoriesItem Covert contrast as a stage in the acquisition of phonetics and phonology : working paper(QMU Speech Science Research Centre, 1996) Scobbie, James M.; Gibbon, Fiona; Hardcastle, William J.; Fletcher, PaulPaper adds to the growing body of evidence that children can acquire phonological systems before they are able to master the phonetic skills needed to convey the contrasts in that systemItem 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 CouncilAccording 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.