Do Infants With Down Syndrome Show an Early Receptive Language Advantage?

Pragmatic competence in people with dual diagnosis: down syndrome and autism spectrum disorder

BACKGROUND

Pragmatics is an area that can be affected in a wide variety of disorders. In this sense, Syndromic Autism is defined as a disorder in which a causal link is established between an associated syndrome and Autism Spectrum Disorder (ASD). Likewise, Down Syndrome (DS) is one of the main genetically based syndromes in which ASD is described as one of its possible manifestations. In this direction, people with DS are described as social beings whereas in ASD there seems to be a specific alteration of this domain.

METHODS

In this study, pragmatic performance was analysed in a sample of 72 participants, where comparisons were made between the scores obtained by children with ASD (n = 24), with DS (n = 24) and with DS + ASD (n = 24).

RESULTS

The Social Communication Questionnaire (SCQ), the Block Objective and Criterial Language Battery (BLOC-SR) and the Neuropsychology subtest (NEPSY-II) aimed at Theory of Mind (ToM) identified significant differences between the groups. However, two-to-two comparisons reported no significant differences between DS and DS + ASD.

CONCLUSIONS

Although several studies report differences between the three proposed groups, our data seem to suggest that ASD symptomatology in DS is associated with Intellectual Developmental Disorder (IDD). However, the lack of solid scientific evidence regarding comorbid diagnosis makes further research along these lines indispensable.

TRIAL REGISTRATION

This study was approved by the Ethics Committee for Social Research at UCLM with reference CEIS-704,511-L8M4.

The Perfect Match! A Review and Tutorial on Issues Related to Matching Groups in Investigations of Children with Neurodevelopmental Conditions

Research concerned with children and young people who have neurodevelopmental disabilities (ND) in relation to early language acquisition usually involves comparisons with matched group(s) of typically developing individuals. In these studies, several important and complex issues need to be addressed. Three major issues are related to: (1) the choice of a variables on which to carry out group matching; (2) recruiting children into the study; and (3) the statistical analysis of the data. To assist future research on this topic, we discuss each of these three issues and provide recommendations about what we believe to be the best course of action. To provide a comprehensive review of the methodological issues, we draw on research beyond the topic of early language acquisition. Our overall aim is to contribute to research that considers questions about delay or differences in development patterns of development and about identifying potentially causal variables.

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.

A systematic review of speech, language and communication interventions for children with Down syndrome from 0 to 6 years

BACKGROUND

Speech and language acquisition can be a challenge for young children with Down syndrome (DS), and while early intervention is important, we do not know what early interventions exist and how effective they may be.

AIMS

To systematically review existing early speech, language and communication interventions for young children with DS from birth up to 6 years, and to investigate their effectiveness in improving speech, language and communication outcomes in children with DS. Other outcomes are changes in parental behaviour and their responsiveness METHODS & PROCEDURES: We conducted a systematic search of relevant electronic databases to identify early intervention studies targeting speech, language and communication outcomes in children with DS published up to May 2020. A total of 11 studies that met the inclusion criteria were synthesized and appraised for quality using the PEDro-P scale. There were a total of 242 children. We identified three types of intervention: communication training and responsive teaching, early stimulation programme, and dialectic-didactic approach.

MAIN CONTRIBUTION

The findings from nine out of the 11 studies reported positive outcomes for children's language and communication up to 18 months following the intervention. All nine studies reported interventions that were co-delivered by parents and clinicians. However, there was also a de-accelerated growth in requesting behaviours in the intervention group reported by one study as well as a case of no improvement for the intervention group. Three studies provided some evidence of improvements to parent outcomes, such as increased parental language input and increased responsiveness. However, there was a moderate to high risk of bias for all studies included.

CONCLUSIONS

The findings from this review suggest that interventions that have high dosage, focus on language and communication training within a naturalistic setting, and are co-delivered by parents and clinicians/researchers may have the potential to provide positive outcomes for children with DS between 0 and 6 years of age. Due to the limited number of studies, limited heterogeneous data and the moderate to high risk of bias across studies, there is an urgent need for higher quality intervention studies in the field to build the evidence base.

WHAT THIS PAPER ADDS

What is already known on the subject Speech and language acquisition is usually delayed in children with DS, yet there are currently no standard interventions for children under 6. A number of research-based interventions exist in the literature, yet it is unknown how effective these are. What this study adds to existing knowledge This is the first systematic review that specifically and exclusively focuses on parent- and non-parent-mediated speech, language and communication interventions for children with DS between 0 and 6 years of age. It complements three existing recent reviews, each of which has a slightly different focus. The previously published reviews have covered only parent-mediated interventions, excluding interventions not mediated by parents, have reviewed interventions including children and adults, without any mention of what early interventions may be like or how effective these may be for young children with DS, have not always assessed risk of bias or have focused specifically on language interventions excluding those focusing on speech articulation or pre-linguistic skills. The findings from the current review suggest that interventions that have high dosage focus on language and communication training within a naturalistic setting and are co-delivered by parents and clinicians/researchers may have the potential to provide positive outcomes for children with Diwn syndrome from 0 to 6. We acknowledge that the current evidence base comes from studies with moderate to high risk of bias, hence our conclusions are not definitive. What are the potential or actual clinical implications of this work? Speech and language therapists will have synthesized information and a quick reference point on what type of interventions exist for children with DS under the age of 6, and evidence of which intervention approaches may be promising in terms of providing positive outcomes. However, it is acknowledged that, due to the limited number of studies and the moderate to high risk of bias inherent in the evidence, there is an urgent need for higher quality intervention studies in the field to build the evidence base.

The Association between Difficulties with Speech Fluency and Language Skills in a National Age Cohort of Children with Down Syndrome

The present study (a) addressed difficulties in speech fluency in children with Down syndrome and typically developing children at a similar non-verbal level and (b) examined the association between difficulties with speech fluency and language skills in children with Down syndrome. Data from a cross-sectional parent survey that included questions about children's difficulties with speech fluency, as well as clinical tests from a national age cohort of 43 six-year-olds with Down syndrome and 57 young typically developing children, were collected. Fisher's exact test, Student's t-test, linear regression, and density ellipse scatter plots were used for analysis. There was a significantly higher occurrence of parent-reported difficulties with speech fluency in the children with Down syndrome. Higher language scores were significantly associated with a lower degree of difficulties; this association was strongest for vocabulary and phonological skills. Although difficulties with speech fluency were not reported for all children with Down syndrome, a substantially higher occurrence of such difficulties was reported compared to that for typically developing children. The significant association between difficulties with speech fluency and the level of language functioning suggests that speech fluency and language skills should be taken into consideration when planning treatment for children with Down syndrome.