Auditory Perception and Ultrasound Biofeedback Treatment Outcomes for Children With Residual /ɹ/ Distortions: A Randomized Controlled Trial

Intervention for residual speech errors in adolescents and adults: A systematised review

When speech sound errors persist beyond childhood they are classified as residual speech errors (RSE) and may have detrimental impacts on an individual's social, educational and employment participation. Despite this, individuals who present with RSE are usually not prioritised on large caseloads. The aim of this literature review was to examine what intervention approaches are available in remediating RSE, and how effective are they for adolescents and adults? A systematised review was undertaken. Comprehensive and systematic searching included search of terms across seven databases, forward and reverse citation searching, and key author contact. Thirty articles underwent critical appraisal before data extraction. Inductive thematic analysis was done before completion of a narrative review. Twenty-three (76.6%) of the articles were from the US and most studies involved intervention for 'r' (90%). Intervention approaches for RSE involved traditional articulation therapy, auditory perceptual training, instrumental approaches, and approaches based on principles of motor learning. Twenty-one studies (70%) investigated the use of more than one intervention approach. Measures of intervention efficacy varied between studies; however, any intervention approach tended to be more successful if delivered in a more intensive schedule. A variety of approaches can be used for RSE, but a combination of high intensity, traditional therapy with adjunctive instrumental biofeedback may be most effective, especially with highly motivated individuals. Unfortunately, this usually requires costly equipment and training to implement. More information about the best dosage and intensity intervention for RSE, evaluated for a larger number of phonemes across other languages and dialects is required.

Comparing online versus laboratory measures of speech perception in older children and adolescents

Given the increasing prevalence of online data collection, it is important to know how behavioral data obtained online compare to samples collected in the laboratory. This study compares online and in-person measurement of speech perception in older children and adolescents. Speech perception is important for assessment and treatment planning in speech-language pathology; we focus on the American English /ɹ/ sound because of its frequency as a clinical target. Two speech perception tasks were adapted for web presentation using Gorilla: identification of items along a synthetic continuum from rake to wake, and category goodness judgment of English /ɹ/ sounds in words produced by various talkers with and without speech sound disorder. Fifty typical children aged 9-15 completed these tasks online using a standard headset. These data were compared to a previous sample of 98 typical children aged 9-15 who completed the same tasks in the lab setting. For the identification task, participants exhibited smaller boundary widths (suggestive of more acute perception) in the in-person setting relative to the online setting. For the category goodness judgment task, there was no statistically significant effect of modality. The correlation between scores on the two tasks was significant in the online setting but not in the in-person setting, but the difference in correlation strength was not statistically significant. Overall, our findings agree with previous research in suggesting that online and in-person data collection do not yield identical results, but the two contexts tend to support the same broad conclusions. In addition, these results suggest that online data collection can make it easier for researchers connect with a more representative sample of participants.

Preliminary Speech Perception Performance Profiles of School-Age Children With Childhood Apraxia of Speech, Speech Sound Disorder, and Typical Development

PURPOSE

Limited research exists assessing speech perception in school-age children with speech sound disorder (SSD) and childhood apraxia of speech (CAS); despite early evidence that speech perception may lead to error-prone motor planning/programming. In this study, we examine speech perception performance in school-age children with and without speech production deficits.

METHOD

Speech perception was assessed using the Wide Range Acoustic Accuracy Scale to determine the just-noticeable difference in discrimination for three consonant-vowel syllable contrasts (/bɑ/-/wɑ/, /dɑ/-/gɑ/, /ɹɑ/-/wɑ/), each varying along a single acoustic parameter for seven children with CAS with rhotic errors, seven children with SSD with rhotic errors, and seven typically developing (TD) children.

RESULTS

Findings revealed statistically significant mean differences between perceptual performance of children with CAS when compared to TD children for discrimination of /ɹɑ/-/wɑ/ contrasts. Large effect sizes were also observed for comparisons of /ɹɑ/-/wɑ/ contrasts between children with CAS, SSD, and TD peers. Additionally, large effect sizes were observed for /dɑ/-/gɑ/ contrasts between children with CAS and SSD and TD children despite nonsignificant mean differences in group performance.

CONCLUSIONS

Overall, mean outcome scores suggest that school-age children with CAS and persistent rhotic errors demonstrated less accurate speech perception skills relative to TD children for the /ɹɑ/-/wɑ/ contrasts. However, the relatively small sample sizes per group limit the extent to which these findings may be generalized to the broader population.

Neural Changes in Children With Residual Speech Sound Disorder After Ultrasound Biofeedback Speech Therapy

PURPOSE

Children with residual speech sound disorders (RSSD) have shown differences in neural function for speech production, as compared to their typical peers; however, information about how these differences may change over time and relative to speech therapy is needed. To address this gap, we used functional magnetic resonance imaging (fMRI) to examine functional activation and connectivity on adaptations of the syllable repetition task (SRT-Early Sounds and SRT-Late Sounds) in children with RSSD before and after a speech therapy program.

METHOD

Sixteen children with RSSD completed an fMRI experiment before (Time 1) and after (Time 2) a speech therapy program with ultrasound visual feedback for /ɹ/ misarticulation. Progress in therapy was measured via perceptual ratings of productions of untreated /ɹ/ word probes. To control for practice effects and developmental change in patterns of activation and connectivity, 17 children with typical speech development (TD) completed the fMRI at Time 1 and Time 2. Functional activation was analyzed using a region-of-interest approach and functional connectivity was analyzed using a seed-to-voxel approach.

RESULTS

Children with RSSD showed a range of responses to therapy. After correcting for multiple comparisons, we did not observe any statistically significant cross-sectional differences or longitudinal changes in functional activation. A negative relationship between therapy effect size and functional activation in the left visual association cortex was on the SRT-Late Sounds after therapy, but it did not survive correction for multiple comparisons. Significant longitudinal changes in functional connectivity were observed for the RSSD group on SRT-Early Sounds and SRT-Late Sounds, as well as for the TD group on the SRT-Early Sounds. RSSD and TD groups showed connectivity differences near the left insula on the SRT-Late Sounds at Time 2.

CONCLUSION

RSSD and treatment with ultrasound visual feedback may thus be associated with neural differences in speech motor and visual association processes recruited for speech production.

The Relationship Between Speech Perception, Speech Production, and Vocabulary Abilities in Children: Insights From By-Group and Continuous Analyses

PURPOSE

The purpose of this study was to explore the relationship between speech perception, speech production, and vocabulary abilities in children with and without speech sound disorders (SSDs), analyzing the data both by group and continuously.

METHOD

Sixty-one Australian English-speaking children aged 48-69 months participated in this study. Children's speech production abilities ranged along the continuum from SSDs through to typical speech. Their vocabulary abilities ranged along the continuum from typical to above average ("lexically precocious"). Children completed routine speech and language assessments in addition to an experimental Australian English lexical and phonetic judgment task.

RESULTS

When analyzing data by group, there was no significant difference between the speech perception ability of children with SSDs and that of children without SSDs. Children with above-average vocabularies had significantly better speech perception ability than children with average vocabularies. When analyzing data continuously, speech production and vocabulary were both significant positive predictors of variance in speech perception ability, both individually in simple linear regression and when combined in multiple linear regression. There was also a significant positive correlation between perception and production of two of the four target phonemes tested (i.e., /k/ and /ʃ/) among children in the SSD group.

CONCLUSIONS

Results from this study provide further insight into the complex relationship between speech perception, speech production, and vocabulary abilities in children. While there is a clinical and important need for categorical distinctions between SSDs and typically developing speech, findings further highlight the value of investigating speech production and vocabulary abilities continuously and categorically. By capturing the heterogeneity among children's speech production and vocabulary abilities, we can advance our understanding of SSDs in children.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.22229674.

Auditory and Somatosensory Development for Speech in Later Childhood

PURPOSE

This study collected measures of auditory-perceptual and oral somatosensory acuity in typically developing children and adolescents aged 9-15 years. We aimed to establish reference data that can be used as a point of comparison for individuals with residual speech sound disorder (RSSD), especially for RSSD affecting American English rhotics. We examined concurrent validity between tasks and hypothesized that performance on at least some tasks would show a significant association with age, reflecting ongoing refinement of sensory function in later childhood. We also tested for an inverse relationship between performance on auditory and somatosensory tasks, which would support the hypothesis of a trade-off between sensory domains.

METHOD

Ninety-eight children completed three auditory-perceptual tasks (identification and discrimination of stimuli from a "rake"-"wake" continuum and category goodness judgment for naturally produced words containing rhotics) and three oral somatosensory tasks (bite block with auditory masking, oral stereognosis, and articulatory awareness, which involved explicit judgments of relative tongue position for different speech sounds). Pairwise associations were examined between tasks within each domain and between task performance and age. Composite measures of auditory-perceptual and somatosensory functions were used to investigate the possibility of a sensory trade-off.

RESULTS

Statistically significant associations were observed between the identification and discrimination tasks and the bite block and articulatory awareness tasks. In addition, significant associations with age were found for the category goodness and bite block tasks. There was no statistically significant evidence of a trade-off between auditory-perceptual and somatosensory domains.

CONCLUSIONS

This study provided a multidimensional characterization of speech-related sensory function in older children/adolescents. Complete materials to administer all experimental tasks have been shared, along with measures of central tendency and dispersion for scores in two subgroups of age. Ultimately, we hope to apply this information to make customized treatment recommendations for children with RSSD based on sensory profiles.

Speech Perception Variability in Childhood Apraxia of Speech: Implications for Assessment and Intervention

PURPOSE

Beyond hallmark production deficits characterizing childhood apraxia of speech (CAS), largely attributed to disruption(s) in speech motor planning, children with CAS often present with co-occurring speech perception and language difficulties. Thus, careful consideration of the potential for speech perception difficulties to have cascading downstream effects on intervention responsiveness and real-life functioning for some children with CAS is highly important. The purpose of this tutorial was to consider the impact of speech perception abilities in children with CAS, which carries implications for caring for the needs of the whole child.

METHOD

This tutorial summarizes the current literature on speech perception and how it relates to speech production, language, and reading abilities for children with CAS. We include case illustrations that are adapted from real clinical scenarios illustrating how speech perception difficulties may impact some children with CAS and provide recommendations for incorporating speech perception into assessment and intervention practices.

RESULTS

Although speech perception difficulties do not seem to be a core deficit of CAS, they are strongly linked to language difficulties, which are highly prevalent among children with CAS. Speech perception and language difficulties are also associated with reading difficulties and risk for lower academic achievement.

CONCLUSIONS

Children with CAS who have co-occurring language difficulties likely also demonstrate speech perception deficits, which puts them at heightened risk for reading difficulties and struggles with academic achievement. Comprehensive assessment of children with CAS should address speech perception and production, language, and reading abilities, which carries important implications for multifaceted approaches to intervention.

Characterizing sensorimotor profiles in children with residual speech sound disorder: a pilot study

PURPOSE

Children with speech errors who have reduced motor skill may be more likely to develop residual errors associated with lifelong challenges. Drawing on models of speech production that highlight the role of somatosensory acuity in updating motor plans, this pilot study explored the relationship between motor skill and speech accuracy, and between somatosensory acuity and motor skill in children. Understanding the connections among sensorimotor measures and speech outcomes may offer insight into how somatosensation and motor skill cooperate during speech production, which could inform treatment decisions for this population.

METHOD

Twenty-five children (ages 9-14) produced syllables in an /ɹ/ stimulability task before and after an ultrasound biofeedback treatment program targeting rhotics. We first tested whether motor skill (as measured by two ultrasound-based metrics of tongue shape complexity) predicted acoustically measured accuracy (the normalized difference between the second and third formant frequencies). We then tested whether somatosensory acuity (as measured by an oral stereognosis task) predicted motor skill, while controlling for auditory acuity.

RESULTS

One measure of tongue shape complexity was a significant predictor of accuracy, such that higher tongue shape complexity was associated with lower accuracy at pre-treatment but higher accuracy at post-treatment. Based on the same measure, children with better somatosensory acuity produced /ɹ/ tongue shapes that were more complex, but this relationship was only present at post-treatment.

CONCLUSION

The predicted relationships among somatosensory acuity, motor skill, and acoustically measured /ɹ/ production accuracy were observed after treatment, but unexpectedly did not hold before treatment. The surprising finding that greater tongue shape complexity was associated with lower accuracy at pre-treatment highlights the importance of evaluating tongue shape patterns (e.g., using ultrasound) prior to treatment, and has the potential to suggest that children with high tongue shape complexity at pre-treatment may be good candidates for ultrasound-based treatment.

Baseline Stimulability Predicts Patterns of Response to Traditional and Ultrasound Biofeedback Treatment for Residual Speech Sound Disorder

PURPOSE

This study aimed to identify predictors of response to treatment for residual speech sound disorder (RSSD) affecting English rhotics. Progress was tracked during an initial phase of traditional motor-based treatment and a longer phase of treatment incorporating ultrasound biofeedback. Based on previous literature, we focused on baseline stimulability and sensory acuity as predictors of interest.

METHOD

Thirty-three individuals aged 9-15 years with residual distortions of /ɹ/ received a course of individual intervention comprising 1 week of intensive traditional treatment and 9 weeks of ultrasound biofeedback treatment. Stimulability for /ɹ/ was probed prior to treatment, after the traditional treatment phase, and after the end of all treatment. Accuracy of /ɹ/ production in each probe was assessed with an acoustic measure: normalized third formant (F3)-second formant (F2) distance. Model-based clustering analysis was applied to these acoustic measures to identify different average trajectories of progress over the course of treatment. The resulting clusters were compared with respect to acuity in auditory and somatosensory domains.

RESULTS

All but four individuals were judged to exhibit a clinically significant response to the combined course of treatment. Two major clusters were identified. The "low stimulability" cluster was characterized by very low accuracy at baseline, minimal response to traditional treatment, and strong response to ultrasound biofeedback. The "high stimulability" group was more accurate at baseline and made significant gains in both traditional and ultrasound biofeedback phases of treatment. The clusters did not differ with respect to sensory acuity.

CONCLUSIONS

This research accords with clinical intuition in finding that individuals who are more stimulable at baseline are more likely to respond to traditional intervention, whereas less stimulable individuals may derive greater relative benefit from biofeedback.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.20422236.

Clinical Considerations for Speech Perception in School-Age Children With Speech Sound Disorders: A Review of the Current Literature

PURPOSE

The purpose of this study was to synthesize the methodological variability in the speech perception literature for school-age children with residual speech sound disorder (RSSD), with the primary intention of using the existing knowledge to inform clinical decisions and optimize treatment outcomes for children.

METHOD

Ten electronic databases were systematically searched to identify articles examining the speech perception skills of school-age children with RSSD. A total of 11 articles met inclusion criteria, reporting of methodological characteristics was rated and compared across studies, and findings were summarized.

RESULTS

The majority of studies reviewed here confirmed the presence of a perceptual deficit for a subset of children with RSSD. However, marked variability across study methodologies limits clinical interpretation and application of the findings.

CONCLUSIONS

Despite limited research in children with RSSD and wide variability across study procedures, stimulus type, perception type, and task type emerged as potential key factors that provide critical insight into a child's perceptual skill. The current evidence suggests that deficits in speech perception may significantly impact acquisition of accurate phoneme production for children with RSSD. Furthermore, these findings suggest that assessment and treatment of speech perception may be a critical component of an intervention program for school-age children, although further research is needed to determine effective clinical procedures.

Moving Beyond Single Word Acquisition of Speech Sounds to Connected Speech Development With Dynamic Assessment

PURPOSE

The aim of this study was to document speech sound development across early childhood from a dynamic assessment (DA) perspective that captures a breadth of linguistic environments using the Glaspey Dynamic Assessment of Phonology (Glaspey, 2019), as well as to provide normative data for speech-language pathologists to compare speech skills when making clinical decisions and provide historical context. Targets of English were evaluated via DA for the (a) age of acquisition in single words; (b) continued development through connected speech; (c) early, mid, and late sequence; and (d) differences between single word and connected speech productions.

METHOD

Data were extracted from the reported results of the norming study for the Glaspey Dynamic Assessment of Phonology, which included a representative sample of 880 children ages 3 years to 10;11 (years;months). Comparisons were made with 49 items including multisyllabic words, clusters, and phonemes of English across word positions.

RESULTS

Assessment with DA showed that acquisition in single words is nearly complete by age 6 years with a 90% mastery level, and the sequence suggests an Early-13, Mid-16, and Late-14 for items by word position. In connected speech, a wider range of progression is evident from the emergence of sound production at 50%, 75%, and 90% mastery levels with observed changes between ages 3 and 10 years.

CONCLUSIONS

Given a DA approach across connected linguistic environments, children continue to progress in their development of speech sounds from early childhood well into their school-age years and for some sounds beyond the age of 10 years. DA challenges the language system to better reflect children's developmental progression.

Treatment generalization from trained /ɹ/ to untrained /l/: a case study of persisting distortion errors

The extent to which treatment of speech errors that are phonetic in nature (i.e., distortions) produces generalization to untrained sounds is not well understood. This case study reports a child referred for treatment of a velarized distortion of American English /ɹ/, who also demonstrated an inconsistent velarized distortion of /l/. Acoustic analysis revealed evidence of a covert contrast between /ɹ/ and /l/ prior to treatment. Ultrasound biofeedback treatment and perceptual training targeted /ɹ/ only, but progress was tracked for both /ɹ/ and /l/. Substantial improvements in perceptually rated accuracy and significant changes in acoustic features were observed for both sounds, indicating generalization. These results highlight that generalization from trained to untrained sounds is possible for children with residual speech errors characterized by phonetic distortions.

Autism-Centered Therapy for Childhood Apraxia of Speech (ACT4CAS): A Single-Case Experimental Design Study

Purpose A subset of children with autism spectrum disorder (ASD) has speech sound disorders, including childhood apraxia of speech (CAS). To date, virtually all speech treatment studies consider ASD an exclusionary criterion, resulting in little scientific evidence for treatment of CAS for children who also have ASD. This study proposes and tests a novel approach, Autism-Centered Therapy for Childhood Apraxia of Speech (ACT4CAS), as a theoretically and clinically informed speech treatment option for this population. Method Using a multiple-baseline design within and across participants, three children with co-occurring ASD and CAS received 11-18 treatment sessions. Treatment targets were individually designed and matched with untreated control words. Probes were administered at the start of each session to assess speech production accuracy perceptually. Changes in production accuracy were examined through visual inspection and quantified with effect sizes. Results Findings were mixed, with one child showing significant gains for half of the treated targets at follow-up and two children showing no clear improvement. Conclusions Preliminary evidence suggests potentially positive treatment effects for ACT4CAS when implemented as intended, although treatment intensity and disorder severity likely influence treatment outcome. Replication and comparison of ACT4CAS to other speech treatments is needed. Supplemental Material https://doi.org/10.23641/asha.14110445.

Auditory-perceptual acuity in rhotic misarticulation: baseline characteristics and treatment response

The rhotic sound /r/ is one of the latest-emerging sounds in English, and many children receive treatment for residual errors affecting /r/ that persist past the age of 9. Auditory-perceptual abilities of children with residual speech errors are thought to be different from their typically developing peers. This study examined auditory-perceptual acuity in children with residual speech errors affecting /r/ and the relation of these skills to production accuracy, both before and after a period of treatment incorporating visual biofeedback. Identification of items along an /r/-/w/ continuum was assessed prior to treatment. Production accuracy for /r/ was acoustically measured from standard/r/stimulability probes elicited before and after treatment. Fifty-nine children aged 9-15 with residual speech errors (RSE) affecting /r/ completed treatment, and forty-eight age-matched controls who completed the same auditory-perceptual task served as a comparison group. It was hypothesized that children with RSE would show lower auditory-perceptual acuity than typically developing speakers and that higher auditory-perceptual acuity would be associated with more accurate production before treatment. It was also hypothesized that auditory-perceptual acuity would serve as a mediator of treatment response. Results indicated that typically developing children have more acute perception of the /r/-/w/ contrast than children with RSE. Contrary to hypothesis, baseline auditory-perceptual acuity for /r/ did not predict baseline production severity. For baseline auditory-perceptual acuity in relation to biofeedback efficacy, there was an interaction between auditory-perceptual acuity and gender, such that higher auditory-perceptual acuity was associated with greater treatment response in female, but not male, participants.

Measuring Speech Perception Using the Wide-Range Acoustic Accuracy Scale: Preliminary Findings

Purpose

Speech perception requires individuals to hear and differentiate acoustic signals integral to effective communication. Measuring speech perception in children is challenging because speech perception methodology typically requires lengthy experiments that may fatigue children, resulting in limited knowledge of developmental perceptual skills. In this study, we used an adaptive tracking measure along with a wide range of acoustic stimuli to explore how adults, typically developing (TD) children, and children with speech sound disorder (SSD) perceive small acoustic differences in synthetic speech stimuli.

Method

Twenty-four adults, 15 TD children, and 15 children with SSD between the ages of 7;0–14;0 (years;months) were administered a newly developed perceptual assessment, the Wide-Range Acoustic Accuracy Scale, to determine the just-noticeable difference in discrimination for three separate syllable contrasts. Each syllable contrast varied along a single acoustic parameter: formant transition duration for /bɑ/–/wɑ/, F3 onset frequency for /dɑ/–/ɡɑ/, and F3–F2 distance for /rɑ/–/wɑ/.

Results

Findings revealed that adults and TD children did not differ in their discrimination of any syllable contrast, but adults significantly differed from SSD children on all syllable contrasts. TD children and children with SSD differed only on the /rɑ/–/wɑ/ contrast.

Conclusions

Children with SSD demonstrate less accurate and more variable perception skills relative to adults and TD children for /bɑ/–/wɑ/, /dɑ/–/ɡɑ/, and /rɑ/–/wɑ/ syllable contrasts. Clinical implications of the utility of the Wide-Range Acoustic Accuracy Scale are discussed.