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

Research Priorities for Childhood Apraxia of Speech: A Long View

This article introduces the Journal of Speech, Language, and Hearing Research Special Issue: Selected Papers From the 2022 Apraxia Kids Research Symposium. The field of childhood apraxia of speech (CAS) has developed significantly in the past 15 years, with key improvements in understanding of basic biology including genetics, neuroscience, and computational modelling; development of diagnostic tools and methods; diversity of evidence-based interventions with increasingly rigorous experimental designs; and understanding of impacts beyond impairment-level measures. Papers in this special issue not only review and synthesize the some of the substantial progress to date but also present novel findings addressing critical research gaps and adding to the overall body of knowledge. A second aim of this prologue is to report the current research needs in CAS, which arose from symposium discussions involving researchers, clinicians, and Apraxia Kids community members (including parents of children with CAS). Four primary areas of need emerged from discussions at the symposium. These were: (a) What questions should we ask? (b) Who should be in the research? (c) How do we conduct the research? and (d) How do we move from research to practice? Across themes, symposium attendees emphasized the need for CAS research to better account for the diversity of people with CAS and improve the timeliness of implementation of high-level evidence-based practice across the lifespan. It is our goal that the articles and prologue discussion in this special issue provide an appreciation of advancements in CAS research and an updated view of the most pressing needs for future research.

Expanding the molecular landscape of childhood apraxia of speech: evidence from a single-center experience

Background

Childhood apraxia of speech (CAS) is a genetically heterogeneous pediatric motor speech disorder. The advent of whole exome sequencing (WES) and whole genome sequencing techniques has led to increased identification of pathogenic variants in CAS genes. In an as yet uncharacterized Italian cohort, we aimed both to identify new pathogenic gene variants associated with CAS, and to confirm the disease-related role of genes already reported by others. We also set out to refine the clinical and neurodevelopmental characterization of affected children, with the aim of identifying specific, gene-related phenotypes.

Methods

In a single-center study aiming to explore the genetic etiology of CAS in a cohort of 69 Italian children, WES was performed in the families of the 34 children found to have no copy number variants. Each of these families had only one child affected by CAS.

Results

High-confidence (HC) gene variants were identified in 7/34 probands, in two of whom they affected KAT6A and CREBBP, thus confirming the involvement of these genes in speech impairment. The other probands carried variants in low-confidence (LC) genes, and 20 of these variants occurred in genes not previously reported as associated with CAS. UBA6, ZFHX4, and KAT6A genes were found to be more enriched in the CAS cohort compared to control individuals. Our results also showed that most HC genes are involved in epigenetic mechanisms and are expressed in brain regions linked to language acquisition processes.

Conclusion

Our findings confirm a relatively high diagnostic yield in Italian patients.

A Goal-Writing Framework for Motor-Based Intervention for Childhood Apraxia of Speech

PURPOSE

There are multiple frameworks for goal writing that are applicable to the practice of speech-language pathology. Motor-based speech disorders are a subset of speech sound disorders that are thought to require specific elements of intervention that are typically not addressed in the traditional frameworks used in the clinical setting. The purpose of this tutorial is to review general approaches of goal writing and suggest additional elements that may be used to improve the efficiency and effectiveness of treatment for childhood motor speech disorders, specifically childhood apraxia of speech (CAS).

METHOD

Existing models of goal writing were reviewed to ascertain elements common to most of these models. A basic framework was chosen and modified to include behaviors, conditions, and approaches to goal measurement tailored to the clinical needs of children with CAS. A resource for clinical decision making for children with CAS was developed to inform goal writing at the onset of treatment and adaptations that occur over the course of treatment. Case studies are presented to demonstrate how the presented framework can be applied to writing goals for motor-based treatment for two different children with CAS.

DISCUSSION

Children with CAS require a specialized approach to intervention, which requires goals to reflect the unique clinical needs of this population. This tutorial offers resources that use the best available research evidence and current understanding of effective treatment practices for CAS to guide clinical decision making for motor-based intervention and goal writing. This tutorial is intended to guide treatment planning across varied settings to facilitate progress and optimize treatment outcomes for children with CAS.

Exploring Motor Speech Disorders in Low and Minimally Verbal Autistic Individuals: An Auditory-Perceptual Analysis

PURPOSE

Motor deficits are widely documented among autistic individuals, and speech characteristics consistent with a motor speech disorder have been reported in prior literature. We conducted an auditory-perceptual analysis of speech production skills in low and minimally verbal autistic individuals as a step toward clarifying the nature of speech production impairments in this population and the potential link between oromotor functioning and language development.

METHOD

Fifty-four low or minimally verbal autistic individuals aged 4-18 years were video-recorded performing nonspeech oromotor tasks and producing phonemes, syllables, and words in imitation. Three trained speech-language pathologists provided auditory perceptual ratings of 11 speech features reflecting speech subsystem performance and overall speech production ability. The presence, attributes, and severity of signs of oromotor dysfunction were analyzed, as were relative performance on nonspeech and speech tasks and correlations between perceptual speech features and language skills.

RESULTS AND CONCLUSIONS

Our findings provide evidence of a motor speech disorder in this population, characterized by perceptual speech features including reduced intelligibility, decreased consonant and vowel precision, and impairments of speech coordination and consistency. Speech deficits were more associated with articulation than with other speech subsystems. Speech production was more impaired than nonspeech oromotor abilities in a subgroup of the sample. Oromotor deficits were significantly associated with expressive and receptive language skills. Findings are interpreted in the context of known characteristics of the pediatric motor speech disorders childhood apraxia of speech and childhood dysarthria. These results, if replicated in future studies, have significant potential to improve the early detection of language impairments, inform the development of speech and language interventions, and aid in the identification of neurobiological mechanisms influencing communication development.

Manual Rhythmic Sequencing Skills in Children With Childhood Apraxia of Speech

PURPOSE

Rhythm is one procedural mechanism that underlies language and motor skill acquisition and has been implicated in children with childhood apraxia of speech (CAS). The purpose of this study is to investigate manual rhythmic sequencing skills in children with a history of or current CAS (hx/CAS) compared to children with typical development (TD).

METHOD

Thirty-eight children (18 with hx/CAS, 20 with TD), ages 5;0-12;8 (years;months), from across the United States participated in an online study. Participants imitated two rhythms in two different conditions, clapping and tapping. We assessed overall accuracy, mean number of beats, pause marking, and rhythmic sequence variability using the Mann-Whitney U test. Effect sizes were calculated to examine the influence of coordinative complexity on performance.

RESULTS

Compared to children with TD, children with hx/CAS marked fewer trials with a pause in both conditions of the easier rhythm and showed lower overall accuracy and more variable rhythmic sequences in both rhythms and conditions. The mean number of beats produced by children with hx/CAS and children with TD did not differ in three out of four rhythms/conditions. Unlike children with TD, children with hx/CAS showed little improvement from clapping to tapping across most dependent measures; reducing coordination demands did not improve performance in children with hx/CAS.

CONCLUSIONS

We found that children with hx/CAS show manual rhythmic deficits that are similar to the deficits they display in speech. These findings provide support for a domain-general cognitive mechanisms account of the rhythmic deficits observed across linguistic and nonlinguistic tasks in children with hx/CAS.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.24052821.