Elaine R. Hitchcock

Retroflex Versus Bunched in Treatment for Rhotic Misarticulation: Evidence From Ultrasound Biofeedback Intervention

PURPOSE To document the efficacy of ultrasound biofeedback treatment for misarticulation of the North American English rhotic in children. Because of limited progress in the first cohort, a series of two closely related studies was conducted in place of a single study. The studies differed primarily in the nature of tongue-shape targets (e.g., retroflex, bunched) cued during treatment. METHOD Eight participants received 8 weeks of individual ultrasound biofeedback treatment targeting rhotics. In Study 1, all 4 participants were cued to match a bunched tongue-shape target. In Study 2, participants received individualized cues aimed at eliciting the tongue shape most facilitative of perceptually correct rhotics. RESULTS Participants in Study 1 showed only minimal treatment effects. In Study 2, all participants demonstrated improved production of rhotics in untreated words produced without biofeedback, with large to very large effect sizes. CONCLUSIONS The results of Study 2 indicate that with proper parameters of treatment, ultrasound biofeedback can be a highly effective intervention for children with persistent rhotic errors. In addition, qualitative comparison of Studies 1 and 2 suggests that treatment for the North American English rhotic should include opportunities to explore different tongue shapes, to find the most facilitative variant for each individual speaker.

Enhancing generalisation in biofeedback intervention using the challenge point framework: A case study

Abstract Biofeedback intervention can help children achieve correct production of a treatment-resistant error sound, but generalisation is often limited. This case study suggests that generalisation can be enhanced when biofeedback intervention is structured in accordance with a “challenge point” framework for speech-motor learning. The participant was an 11-year-old with residual /r/ misarticulation who had previously attained correct /r/ production through a structured course of ultrasound biofeedback treatment but did not generalise these gains beyond the word level. Treatment difficulty was adjusted in an adaptive manner following predetermined criteria for advancing, maintaining, or moving back a level in a multidimensional hierarchy of functional task complexity. The participant achieved and maintained virtually 100% accuracy in producing /r/ at both word and sentence levels. These preliminary results support the efficacy of a semi-structured implementation of the challenge point framework as a means of achieving generalisation and maintenance of treatment gains.

Social, Emotional, and Academic Impact of Residual Speech Errors in School-Aged Children: A Survey Study

Children with residual speech errors face an increased risk of social, emotional, and/or academic challenges relative to their peers with typical speech. Previous research has shown that the effects of speech sound disorder may persist into adulthood and span multiple domains of activity limitations and/or participation restrictions, as defined by the World Health Organizations International Classification of Functioning, Disability and Health model. However, the nature and extent of these influences varies widely across children. This study aimed to expand the evidence base on the social, emotional, and academic impact of residual speech errors by collecting survey data from parents of children receiving treatment for /r/ misarticulation. By examining the relationship between an overall measure of impact (weighted summed score) and responses to 11 survey items, the present study offers preliminary suggestions for factors that could be considered when making decisions pertaining to treatment allocation in this population.

Finding the experts in the crowd: Validity and reliability of crowdsourced measures of children’s gradient speech contrasts

ABSTRACT Perceptual ratings aggregated across multiple nonexpert listeners can be used to measure covert contrast in child speech. Online crowdsourcing provides access to a large pool of raters, but for practical purposes, researchers may wish to use smaller samples. The ratings obtained from these smaller samples may not maintain the high levels of validity seen in larger samples. This study aims to measure the validity and reliability of crowdsourced continuous ratings of child speech, obtained through Visual Analog Scaling, and to identify ways to improve these measurements. We first assess overall validity and interrater reliability for measurements obtained from a large set of raters. Second, we investigate two rater-level measures of quality, individual validity and intrarater reliability, and examine the relationship between them. Third, we show that these estimates may be used to establish guidelines for the inclusion of raters, thus impacting the quality of results obtained when smaller samples are used.

Selecting an acoustic correlate for automated measurement of American English rhotic production in children

Abstract Purpose: A current need in the field of speech–language pathology is the development of reliable and efficient techniques to evaluate accuracy of speech targets over the course of treatment. As acoustic measurement techniques improve, it should become possible to use automated scoring in lieu of ratings from a trained clinician in some contexts. This study asks which acoustic measures correspond most closely with expert ratings of children’s productions of American English /ɹ/ in an effort to develop an automated scoring algorithm for use in treatment targeting rhotics. Method: A series of ordinal mixed-effects regression models were fit over a large sample of childrens productions of words containing /ɹ/ that had previously been rated by three trained clinicians. Akaike/Bayesian Information Criteria were used to select the best-fitting model. Result: Controlling for age, sex, and allophonic contextual differences, the measure that accounted for the most variance in speech rating was F3–F2 distance normalised relative to a sample of age- and sex-matched speakers. Conclusion: We recommend this acoustic measure for use in future automated scoring of children’s production of American English rhotics. We also suggest that computer-based treatment with automated scoring should facilitate increases in treatment dosage by improving options for home practice.

Efficacy of Electropalatography for Treating Misarticulation of /r/

Purpose The purpose of the present study was to document the efficacy of electropalatography (EPG) for the treatment of rhotic errors in school-age children. Despite a growing body of literature using EPG for the treatment of speech sound errors, there is little systematic evidence about the relative efficacy of EPG for rhotic errors. Method Participants were 5 English-speaking children aged 6;10 to 9;10, who produced /r/ at the word level with < 30% accuracy but otherwise showed typical speech, language, and hearing abilities. Therapy was delivered in twice-weekly 30-min sessions for 8 weeks. Results Four out of 5 participants were successful in achieving perceptually and acoustically accurate /r/ productions during within-treatment trials. Two participants demonstrated generalization of /r/ productions to nontreated targets, per blinded listener ratings. Conclusions The present findings support the hypothesis that EPG can improve production accuracy in some children with rhotic errors. However, the utility of EPG is likely to remain variable across individuals. For rhotics, EPG training emphasizes one possible tongue configuration consistent with accurate rhotic production (lateral tongue contact). Although some speakers respond well to this cue, the narrow focus may limit lingual exploration of other acceptable tongue shapes known to facilitate rhotic productions.

Longitudinal observations of typical English voicing acquisition in a 2-year-old child: Stability of the contrast and considerations for clinical assessment

Abstract Early assessment of phonetic and phonological development requires knowledge of typical versus atypical speech patterns, as well as the range of individual developmental trajectories. The nature of data reporting in previous literature on typical voicing acquisition left aspects of the developmental process unclear and limited clinical applicability. This work extends a previous four-month group study to present data for one child over 12 months. Words containing initial /b p d t/ were elicited from a monolingual English-speaking 2-year-old child biweekly for 25 sessions. Voice onset time (VOT) was measured for each stop. For each consonant and recording session, we measured range as well as accuracy, overshoot and discreteness calculated for means and individual tokens. The results underscore the value of token-by-token analyses. They further reveal that typical development may involve an extended period of fluctuating voicing patterns, suggesting that the voiced/voiceless contrast may take months or years to stabilise.

The role of voice onset time in the perception of English voicing contrasts in children’s speech

The perception of phonemic voicing distinctions is typically attributed mainly to voice onset time (VOT). Most previous research focusing on voicing discrimination used synthetic speech stimuli varying in VOT. Results of this work suggest that adult listeners show stable crossover boundaries in the 20-35 ms range. However, no research has evaluated how VOT values correspond to adult labeling regardless of whether the intended target is voiced or voiceless. The present study obtained adult labeling data for natural productions of bilabial and alveolar pairs produced by 2-3-year-old monolingual, English-speaking children. Randomized stimuli were presented twice to 20 listeners resulting in 5,760 rated stimuli. Stimuli were categorized as short VOT ( 35 ms). The findings show that listeners demonstrated the greatest accuracy for bilabials (>99%) and alveolars (>92%) when the target matched the expected VOT duration (i.e., doe → short lag and toe → long lag). As...

Not-quite-naïve listeners: Students as an audience for gamified crowdsourcing

Collecting independent listeners’ judgments of speech accuracy/intelligibility is an essential component of research on speech disorders. Raters can be trained clinicians, students in speech-language pathology, or naive listeners (now commonly recruited online via crowdsourcing platforms such as Amazon Mechanical Turk/AMT). However, limited comparison data exist to guide researchers in determining which rater population to use. We describe a study (Hitchcock et al., in prep) in which 2,256 tokens of English /r/ at the word level, produced by five children receiving intervention for /r/ misarticulation, were rated in a binary fashion using the online platform Experigen. Raters were certified clinicians (n = 3), students in speech-language pathology (n = 9 unique listeners per token), or naive listeners recruited on AMT (n = 9 unique listeners per token). Interrater reliability was higher when comparing modal ratings between clinicians and students (Cohen’s kappa=.73, CI=.7-.77) than between clinicians and ...

Effects of vowel position and place of articulation on voice onset time in children: Longitudinal data

Voice onset time (VOT) has been found to vary according to phonetic context, but past studies report varying magnitudes of effect, and no past work has evaluated the degree to which such effects are consistent over time for a single speaker. This study explores the relationships between vowel position, consonant place of articulation [POA], and voice onset time (VOT) in children, comparing the results to past adult work. VOT in CV/CVC words was measured in nine children ages 5;3–7;6 every two-four weeks for 10 months, for a total of 18 sessions yielding approximately 18,000 tokens for analysis. Bilabial and velar cognate pairs targeted a front-back vowel difference (/i/-/u/, /e/-/o/), while alveolar cognate pairs targeted a mid high-low vowel difference (/o/-/ɑ/). VOT variability over time was also evaluated. Preliminary results suggest that POA yields a robust pattern of bilabial < alveolar < velar, but vowel effects are less clear. Vowel height shows the most obvious effect with consistently longer VOT ...