Rates of Prelinguistic Communication and Early Symbol Use in Young Children With Down Syndrome: Using a Progress-Monitoring Tool to Model Growth

Delivering Enhanced Milieu Teaching to Toddlers With Down Syndrome via Hybrid Telepractice: A Single-Case Experimental Design

PURPOSE

This pilot study investigated delivering enhanced milieu teaching tailored for children with Down Syndrome (EMT-DS) through hybrid telepractice.

METHOD

In this multiple-baseline design across behaviors study, a speech-language pathologist (SLP) taught EMT-DS to three caregivers and their children with DS (22-40 months) using a hybrid service delivery model. Sessions were conducted in person and via telepractice. The SLP taught caregivers EMT-DS, emphasizing the use of (a) four target EMT strategies: matched turns, expansions, time delays, and milieu teaching episodes; (b) augmentative and alternative communication (AAC; manual signs, speech-generating device); and (c) aided AAC modeling. The SLP provided caregiver instruction following the teach-model-coach-review approach. Caregiver outcomes were the accuracy (primary) and frequency (secondary) of EMT strategy use. Child outcomes were exploratory and included the rate of symbolic communication acts, weighted number of communication acts, and number of different words (NDW).

RESULTS

There was a functional relation between the intervention and the accuracy and frequency of EMT strategy use for all three caregivers. All caregivers showed an increase in the accuracy for all four target strategies. Caregivers also increased the frequency of the three EMT strategies: expansions, time delays, and milieu teaching episodes. There were no changes in the frequency of matched turns. Caregiver use of EMT strategies maintained for 6 weeks post-intervention. After caregivers learned EMT strategies, gradual increases in the rate of symbolic communication acts and NDW occurred for all three children.

CONCLUSION

Results demonstrate the preliminary efficacy of using a hybrid service delivery model to teach caregivers EMT-DS.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.27115252.

Determining an Effective Language Sample Elicitation Strategy for Early Language Learners Who Speak Using Augmentative and Alternative Communication

PURPOSE

This study evaluates three different language sample elicitation strategies to determine a valid elicitation strategy for early language learners who speak using augmentative and alternative communication (AAC).

METHOD

Ten children who speak using AAC participated in this study. Language samples were elicited from each participant using three strategies: the Communication and Symbolic Behavior Scales (CSBS), a generic play-based elicitation strategy, and automatic data logging. Samples were transcribed and coded. Additionally, each participant's school speech-language pathologist completed a Communication Matrix. Data from coded language samples were correlated with Communication Matrix results to determine the elicitation strategy that yielded the most valid language sample in comparison to Communication Matrix results.

RESULTS

Both the CSBS and the play-based strategy yielded clinically relevant information. Because the log lacked communicative context, resulting data from the log was limited. An analysis of variance revealed significant differences in the amount of information elicited from each elicitation strategy. The CSBS repeatedly elicited the most data, followed by the play-based strategy and then the log. Generic play-based strategy results yielded the most correlations with Communication Matrix data.

CONCLUSIONS

This preliminary data suggest that the play-based elicitation strategy elicited the most valid language sample when compared to the Communication Matrix from early language learners who speak using AAC. Additionally, results suggest that the CSBS may be an effective tool to measure the limits of this population's expressive language abilities.

Parent Responsivity, Language Input, and the Development of Simple Sentences

This study explored responsive and linguistic parent input features during parent-child interactions and investigated how four input categories related to children's production of diverse, simple sentences. Of primary interest was parent use of responsive, simple declarative input sentences. Responsive and linguistic features of parent input to 20 typically developing toddlers at 1;9 were coded during play in a laboratory playroom, then classified into four input categories: responsive, declarative, responsive declarative, and neither responsive nor simple declarative. The percentage of each input category was related to child sentence diversity at 2;6 using Spearman correlations. Parent use of responsive declarative and declarative utterances were both rare. Responsive input was positively correlated with child sentence diversity, and the neither category was negatively correlated with child sentence diversity. The findings provide new support for the importance of balanced conversational turns. Implications for defining both how input is delivered and its linguistic content are discussed.

Vocal Characteristics of Infants at Risk for Speech Motor Involvement: A Scoping Review

PURPOSE

The purpose of this scoping review was to (a) summarize methodological characteristics of studies examining vocal characteristics of infants at high risk for neurological speech motor involvement and (b) report the state of the high-quality evidence on vocal characteristic trends of infants diagnosed or at high risk for cerebral palsy (CP).

METHOD

The PRISMA (Preferred Reporting Items of Systematic Reviews and Meta-Analyses) extension for scoping reviews was followed for reporting our review. Studies measured prelinguistic vocal characteristics of infants under 24 months with birth risk or genetic conditions known to commonly present with speech motor involvement. Fifty-five studies met criteria for Part 1. Eleven studies met criteria for synthesis in Part 2.

RESULTS

A smaller percentage of studies examined infants with or at risk for CP compared to studies examining genetic conditions such as Down syndrome. The median year of publication was 1999, with a median sample size of nine participants. Most studies were conducted in laboratory settings and used human coding of vocalizations produced during caregiver-child interactions. Substantial methodological differences were noted across all studies. A small number of high-quality studies of infants with or at risk for CP revealed high rates of marginal babbling, low rates of canonical babbling, and limited consonant diversity under 24 months. Mixed findings were noted across studies of general birth risk factors.

CONCLUSIONS

There is limited evidence available to support the early detection of speech motor involvement. Large methodological differences currently impact the ability to synthesize findings across studies. There is a critical need to conduct longitudinal research with larger sample sizes and advanced, modern technologies to detect vocal precursors of speech impairment to support the accurate diagnosis and prognosis of speech development in infants with CP and other clinical populations.

A systematic review of assessment instruments for linguistic precursors during child development, ages 6 to 18 months

Linguistic precursors (gaze, joint attention, gestures, social interaction, etc.) have a predictive value over the course of child development. The aim of the present review is to analyze the content structure, and the theoretical perspective, of assessment instruments that focus on linguistic precursors for the 6-18-month age group. The search was achieved through the following citation databases: BVS, MEDLINE/PubMed, Web of Science, SciELO, Redalyc, Web of Science, Google Scholar, as well as the American Speech-Language-Hearing Association (ASHA). Elegible articles were obtained using the following terms: "neuropsychological tests," "nonverbal communication," "child language" and "infant" as well as their equivalents in Spanish and Portuguese. Twenty-six assessment instruments were found to be compatible with the eligibility criteria. From the results, 19 instruments explore various domains of linguistic precursors, while 7 are task-specific proposals. Five instruments are aimed at early detection of signs of Autistic Spectrum Disorder. The implementation of Bruner's model of communicative functions was found on 15% of the instruments. This article provides timely information for clinicians who work with children during early stages of development, in relation to the methodical monitoring, assessment and accompaniment of infants and toddlers during the prelinguistic stage.

Long-Term Effects of Early Communication Interventions: A Systematic Review and Meta-Analysis

PURPOSE

Early language and communication interventions for children with language impairments have been shown to be effective in assessments administered immediately after treatment. The purpose of the current systematic review and meta-analysis was to assess the overall durability of those effects over time and whether durability was related to outcome type, etiology of child language impairments, implementer of intervention, magnitude of posttest effects, time between intervention and follow-up, and study risk of bias.

METHOD

We conducted a systematic search of online databases and reference lists to identify experimental and quasi-experimental group design studies. All studies tested the effects of early communication interventions at least 3 months post-intervention. Participants were children 0-5 years old with language impairments. Coders identified study features and rated methodological quality indicators for all studies. Effect sizes at long-term timepoints and associations with potential moderators were estimated using multilevel meta-analysis with robust variance estimation.

RESULTS

Twenty studies with 129 long-term outcome effect sizes met inclusion criteria. Studies included children with developmental language disorders or language impairment associated with autism. The overall average effect size was small and significant (g = .22, p = .002). Effect size estimates were larger for prelinguistic outcomes (g = .36, p < .001) than for linguistic outcomes (g = .14, p = .101). Significant factors were the posttest effect sizes, the risk of bias for randomized trials, and etiology of language impairment for linguistic outcomes. Time post-intervention did not significantly predict long-term effect sizes.

CONCLUSIONS

Outcomes of early language and communication interventions appear to persist for at least several months post-intervention. More research is needed with collection and evaluation of long-term outcomes, a focus on measurement, and consistency of primary study reporting.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.23589648.

Word type and modality in the emerging expressive vocabularies of preschool children with Down syndrome

BACKGROUND

Previous studies have explored the size and word type composition (nouns, predicates, etc.) of expressive vocabularies of preschool children with Down syndrome, both spoken and signed. Separately, overall preferences for modality of expression have also been explored.

AIMS

To extend previous findings by describing the relationships between expressive vocabulary size and both word type and modality of expression in the preschool period including changes to modality preference over time.

METHODS & PROCEDURES

Mothers of 35 children with Down syndrome, aged 36-66 months and attending the same early intervention programme, completed a version - with both spoken word and sign options - of the New Zealand MacArthur-Bates Communicative Development Inventory (CDI): Words and Sentences. Most mothers completed the CDI on multiple occasions across the duration of the study. Completions (n = 114) were analysed cross-sectionally and longitudinally in terms of (1) word type relative to vocabulary size, (2) modality of expression relative to word type and vocabulary size, and (3) individual trajectories in vocabulary size and modality of expression.

OUTCOMES & RESULTS

(1) Word type relative to vocabulary size was similar to previous studies with a greater proportion of the SOCIAL words being present in the children's vocabularies throughout, followed by NOUNS, PREDICATES and CLOSED class words, with proportions converging as vocabulary sizes increase. (2) An initial spoken word preference for SOCIAL and CLOSED class words and sign preference for NOUNS and PREDICATES was found, with more spoken words in larger vocabularies overall. (3) Individual trajectories were highly variable and also revealed temporary points of regression in overall expressive vocabulary size in some children. Children who shifted from reliance on sign to predominantly spoken word expression did so at different ages and at different vocabulary sizes. At school entry, while most of the children used both modalities, some children continued to rely on sign for most vocabulary items whereas others used only spoken words.

CONCLUSIONS & IMPLICATIONS

An appreciation of both the general trends and potential for individual variation in vocabulary structure, modality of expression and change over time will better position clinicians and education specialists to provide individually tailored support to both preschool and school-aged children with Down syndrome.

WHAT THIS STUDY ADDS

What is already known on this subject Preschool children with Down syndrome have been shown to demonstrate developmental patterns in overall conceptual vocabulary size and word type development broadly similar to typical development. The use of signed vocabulary has also been explored, but independently from word type development and with less attention to individual trajectories in either vocabulary size development or modality preferences throughout the preschool period than is necessary for clinical use. What this paper adds to existing knowledge This study found interactions between word type and modality of expression in relation to vocabulary size as well as a few temporary vocabulary size regressions similar to those found in much younger typically developing children. An initial spoken word preference for social and closed class words, and sign preference for nouns and predicates, was followed by a general trend towards spoken words for all word types as vocabulary (with some fluctuations) increased over time. Children demonstrated considerable individual variation in size of vocabulary and age at which they pivoted from a signed to a spoken word preference. Moreover, while most children used both modalities at school entry, a few retained a sign-only vocabulary and others had moved fully onto spoken word-only expression. What are the potential or actual clinical implications of this work? An understanding of both the general trends and individual variation in vocabulary structure and modality of expression development will better position clinicians and educational specialists to provide individually tailored support to children with Down syndrome.

Exploring Expressive Communication Skills in a Cross-Sectional Sample of Individuals With a Dual Diagnosis of Autism Spectrum Disorder and Down Syndrome

Individuals with a comorbid diagnosis of Down syndrome (DS) and autism spectrum disorder (ASD) have been found to exhibit greater deficits in expressive communication than individuals with DS only. We hypothesized that individuals with a comorbid diagnosis (n = 430) would have significantly lower Communication Matrix scores and specifically social communication scores than individuals with DS alone (n = 4,352). In a sample of 4,782 individuals with DS, scores for individuals with a comorbid diagnosis were on average 18.01 points and 7.26 points lower for total score and social score respectively as compared to individuals with DS. Comorbid diagnosis accounted for 10.5% of the variance in communication scores. Between-group differences in referential gestures and symbolic communication behaviors were also observed.

Teaching Preschoolers With Down Syndrome Using Augmentative and Alternative Communication Modeling During Small Group Dialogic Reading

Purpose This study evaluated the effect of aided augmentative and alternative communication modeling (AAC-MOD) on the communication skills of children with Down syndrome (DS) during small group dialogic reading. Method Four children with DS between 3;1 and 5;3 (years;months; M = 4;5) and 5 typically developing peers between 3;5 and 5;9 (M = 4;3) participated. Effects were examined using a multiple probe across behaviors design with 4 children with DS. To simulate typical dialogic reading routines in inclusive classrooms, a strategy called Read, Ask, Answer, Prompt (Binger, Kent-Walsh, Ewing, & Taylor, 2010) was applied during the baseline and intervention sessions. Results A functional relation was demonstrated between (a) AAC-MOD and percentage of correctly identified symbols for 3 participants, (b) AAC-MOD and rate of symbolic communication for 2 participants, and (c) AAC-MOD and number of different words for 2 participants. Increases in number of multiple word combinations occurred for 2 participants. All 4 children maintained their percentage of correctly identified symbols. Increases in rate of symbolic communication did not generalize to thematic play contexts, a distal measure of response generalization. Conclusion AAC-MOD is an effective strategy for teaching target vocabulary and increasing rate of symbolic communication in young children with DS. Supplemental Material https://doi.org/10.23641/asha.10093538.