The Relationship Between Single-Word Speech Severity and Intelligibility in Childhood Apraxia of Speech

Treatment for Childhood Apraxia of Speech: Past, Present, and Future

PURPOSE

The purposes of this review article were to provide an introduction to and "bird's-eye" overview of the current evidence base for treatment of childhood apraxia of speech (CAS), identify some gaps and trends in this rapidly growing literature, and formulate some future research directions, in order to advance the evidence base and clinical practice for children with CAS.

METHOD

Following a brief introduction outlining important concepts, a narrative review of the CAS treatment literature is provided, and trends and future directions are identified based on this review. The review is organized around four fundamental treatment research questions: (a) "Does Treatment X work?", (b) "Does Treatment X work better than Treatment Y?", (c) "For whom does Treatment X work?", and (d) "What does 'work' mean, anyway?"

RESULTS

A wide range of CAS treatments with varying degrees of evidence for efficacy exists. Research is beginning to emerge that compares different treatments and seeks to determine optimal treatment parameters. Few studies to date have explored child-level predictors of treatment response, and the evidence base currently is limited in scope with respect to populations and outcomes studied.

CONCLUSIONS

A growing evidence base supports the efficacy of a number of treatments for CAS. However, many important gaps in the literature were identified that warrant redoubled and sustained research attention. Research is beginning to emerge that addresses treatment optimization, comparison, candidacy, and outcomes. Suggestions for future research are offered, and the concept of a hypothesized pathway was applied to CAS to illustrate how components of an intervention can effect change in a clinical goal and can help guide development and refinement of treatments for children with CAS.

Speech and Music Therapy in the Treatment of Childhood Apraxia of Speech: An Introduction and a Case Study

PURPOSE

Speech-Music Therapy for Aphasia (SMTA), a method that combines speech therapy and music therapy, is introduced as a treatment method for childhood apraxia of speech (CAS). SMTA will be evaluated in a proof-of-principle study. The first case study is presented herein.

METHOD

SMTA was evaluated in a study with a single-subject experimental design comparing 10 weeks of treatment with 2 months of no treatment. The research protocol included a pretest, baseline phase, treatment phase, posttest, no-treatment phase, and follow-up test. The participant was a boy with CAS aged 5;8 (years;months). Outcome measures were selected to reflect both intelligibility in daily communication as well as features of CAS and speech motor planning and programming.

RESULTS

Results on the Intelligibility in Context Scale-Dutch (ICS-Dutch) and in the analysis of a spontaneous speech sample suggest generalization of treatment effects. Improvements were found in measures that reflect complex speech motor skills, that is, the production of consonant clusters and consistency.

CONCLUSIONS

This case study showed that speech production of the participant improved after treatment with SMTA. Although intelligibility as measured with the ICS-Dutch improved over the study period, objectifying changes at the level of intelligibility in daily communication proved to be difficult. Additional measures may be necessary to gain more insight into treatment effects at this level. Overall, the results of this first case study provide sufficient support and important leads for further evaluation of SMTA in the treatment of CAS in a proof-of-principle study.

Self-Reported Communication Attitudes of Children With Childhood Apraxia of Speech: An Exploratory Study

PURPOSE

Much of the research literature on childhood apraxia of speech (CAS) has focused on understanding, diagnosing, and treating the impairment, rather than examining its functional effect on children's daily lives. This study focuses on the Personal Factors component of the World Health Organization International Classification of Functioning, Disability and Health-Children and Youth Version Framework. Specifically, the purpose was to examine the self-reported communication attitudes of children with CAS.

METHOD

Two validated communication attitude questionnaires were administered to 12 children with CAS enrolled in an intensive speech-focused intervention (age range: 4-10 years old). Children's scores were compared to the questionnaires' typically developing norms. Descriptive analyses explored relationships between communication attitude and CAS severity, caregiver perceptions of communicative participation, frustration ratings during therapy, and change in communication attitude over a brief time.

RESULTS

Older (ages 6-10 years) but not younger (ages 4-5;11 [years;months]) children with CAS were more likely to have negative attitudes about their speech. No clear relationships were observed between communication attitudes and caregiver perceptions of communicative participation; small positive relationships were observed between communication attitude and frustration during therapy. For the younger children, there was also a relationship with CAS severity. For most children, no change in communication attitude was observed over a brief period, though one child appeared to develop more negative and one appeared to develop more positive attitudes.

CONCLUSIONS

These initial findings suggest that older children with CAS may be at greater risk for negative communication attitudes than their peers without CAS. The findings also highlight the need to include more child self-report measures in research. Further implications for CAS assessment and intervention are discussed.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.21834432.

Naive Listener Ratings of Speech Intelligibility Over the Course of Motor-Based Intervention in Children With Childhood Apraxia of Speech

PURPOSE

The aim of this study was to describe changes in speech intelligibility and interrater and intrarater reliability of naive listeners' ratings of words produced by young children diagnosed with childhood apraxia of speech (CAS) over a period of motor-based intervention (dynamic temporal and tactile cueing [DTTC]).

METHOD

A total of 120 naive listeners (i.e., listeners without experience listening to children with speech and/or language impairments; age range: 18-45 years) orthographically transcribed single-word productions by five children (age range: 2;6-3;11 [years;months]) across three time points over an intervention period (baseline, post-treatment, maintenance). Changes in intelligibility and interrater and intrarater reliability were examined within and across time points.

RESULTS

Speech intelligibility significantly increased in children with CAS over the course of treatment, and these gains were also maintained at 6 weeks posttreatment. There was poor-to-fair consistency between listeners (interrater reliability) and excellent consistency within listeners (intrarater reliability) in ratings of speech intelligibility within and across time points.

CONCLUSIONS

Motor-based intervention increases speech intelligibility following a period of DTTC treatment. Variability among naive listeners of speech intelligibility was also present, with intrarater reliability (within listeners) yielding greater consistency than interrater reliability (between listeners). The implications for including naive listeners as raters of speech intelligibility for research and clinical purposes are discussed.

Comorbidity and Severity in Childhood Apraxia of Speech: A Retrospective Chart Review

PURPOSE

The purpose of this study was to investigate comorbidity prevalence and patterns in childhood apraxia of speech (CAS) and their relationship to severity.

METHOD

In this retroactive cross-sectional study, medical records for 375 children with CAS (M age = 4;9 [years;months], SD = 2;9) were examined for comorbid conditions. The total number of comorbid conditions and the number of communication-related comorbidities were regressed on CAS severity as rated by speech-language pathologists during diagnosis. The relationship between CAS severity and the presence of four common comorbid conditions was also examined using ordinal or multinomial regressions.

RESULTS

Overall, 83 children were classified with mild CAS; 35, with moderate CAS; and 257, with severe CAS. Only one child had no comorbidities. The average number of comorbid conditions was 8.4 (SD = 3.4), and the average number of communication-related comorbidities was 5.6 (SD = 2.2). Over 95% of children had comorbid expressive language impairment. Children with comorbid intellectual disability (78.1%), receptive language impairment (72.5%), and nonspeech apraxia (37.3%; including limb, nonspeech oromotor, and oculomotor apraxia) were significantly more likely to have severe CAS than children without these comorbidities. However, children with comorbid autism spectrum disorder (33.6%) were no more likely to have severe CAS than children without autism.

CONCLUSIONS

Comorbidity appears to be the rule, rather than the exception, for children with CAS. Comorbid intellectual disability, receptive language impairment, and nonspeech apraxia confer additional risk for more severe forms of CAS. Findings are limited by being from a convenience sample of participants but inform future models of comorbidity.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.22096622.

Fine motor skill and expressive language in minimally verbal and verbal school-aged autistic children

Fine motor skill is associated with expressive language outcomes in infants who have an autistic sibling and in young autistic children. Fewer studies have focused on school-aged children even though around 80% have motor impairments and 30% remain minimally verbal (MV) into their school years. Moreover, expressive language is not a unitary construct, but it is made up of components such as speech production, structural language, and social-pragmatic language use. We used natural language sampling to investigate the relationship between fine motor and speech intelligibility, mean length of utterance and conversational turns in MV and verbal autistic children between the ages of 4 and 7 while controlling for age and adaptive behavior. Fine motor skill predicted speech production, measured by percent intelligible utterances. Fine motor skill and adaptive behavior predicted structural language, measured by mean length of utterance in morphemes. Adaptive behavior, but not fine motor skill, predicted social-pragmatic language use measured by number of conversational turns. Simple linear regressions by group corrected for multiple comparisons showed that fine motor skill predicted intelligibility for MV but not verbal children. Fine motor skill and adaptive behavior predicted mean length of utterance for both MV and verbal children. These findings suggest that future studies should explore whether MV children may benefit from interventions targeting fine motor along with speech and language into their school years.

The importance of deep speech phenotyping for neurodevelopmental and genetic disorders: a conceptual review

Background

Speech is the most common modality through which language is communicated, and delayed, disordered, or absent speech production is a hallmark of many neurodevelopmental and genetic disorders. Yet, speech is not often carefully phenotyped in neurodevelopmental disorders. In this paper, we argue that such deep phenotyping, defined as phenotyping that is specific to speech production and not conflated with language or cognitive ability, is vital if we are to understand how genetic variations affect the brain regions that are associated with spoken language.

Speech is distinct from language, though the two are related behaviorally and share neural substrates. We present a brief taxonomy of developmental speech production disorders, with particular emphasis on the motor speech disorders childhood apraxia of speech (a disorder of motor planning) and childhood dysarthria (a set of disorders of motor execution). We review the history of discoveries concerning the KE family, in whom a hereditary form of communication impairment was identified as childhood apraxia of speech and linked to dysfunction in the FOXP2 gene. The story demonstrates how instrumental deep phenotyping of speech production was in this seminal discovery in the genetics of speech and language. There is considerable overlap between the neural substrates associated with speech production and with FOXP2 expression, suggesting that further genes associated with speech dysfunction will also be expressed in similar brain regions. We then show how a biologically accurate computational model of speech production, in combination with detailed information about speech production in children with developmental disorders, can generate testable hypotheses about the nature, genetics, and neurology of speech disorders.

Conclusions

Though speech and language are distinct, specific types of developmental speech disorder are associated with far-reaching effects on verbal communication in children with neurodevelopmental disorders. Therefore, detailed speech phenotyping, in collaboration with experts on pediatric speech development and disorders, can lead us to a new generation of discoveries about how speech development is affected in genetic disorders.