Prelinguistic predictors of vocabulary in young children with autism spectrum disorders

A Longitudinal Study of Joint Attention, Motor Imitation and Language Development in Young Children with Autism Spectrum Disorder in Taiwan

This longitudinal study examined early predictors of language development in 74 young children with Autism Spectrum Disorder (ASD) in Taiwan. Participants were assessed twice (initial age between 17 and 35 months) on responding to joint attention (RJA), initiating joint attention (IJA), motor imitation with objects (object imitation; OI) and without objects (manual imitation; MI), and receptive and expressive language. The two assessments were 18 months apart. Results showed that both RJA and MI concurrently and longitudinally predicted receptive and expressive language across the two assessments. These findings were not entirely consistent with the limited and mixed findings of Western longitudinal studies. However, they have implications for early interventions aiming to facilitate language development in children with ASD internationally.

Decreased wrist rotation imitation abilities in children with autism spectrum disorder

Introduction

While meaningless gross motor imitation (GMI) is a common challenge for children diagnosed with autism spectrum disorder (ASD), this topic has not attracted much attention and few appropriate test paradigms have been developed.

Methods

The current study proposed a wrist rotation imitation (WRI) task (a meaningless GMI assignment), and established a WRI ability evaluation system using low-cost wearable inertial sensors, which acquired the simultaneous data of acceleration and angular acceleration during the WRI task. Three metrics (i.e., total rotation time, rotation amplitude, and symmetry) were extracted from those data of acceleration and angular acceleration, and then were adopted to construct classifiers based on five machine learning (ML) algorithms, including k-nearest neighbors, linear discriminant analysis, naive Bayes, support vector machines, and random forests. To illustrate our technique, this study recruited 49 ASD children (aged 3.5-6.5 years) and 59 age-matched typically developing (TD) children.

Results

Findings showed that compared with TD children, those with ASD may exhibit shorter total rotation time, lower rotation amplitude, and weaker symmetry. This implies that children with ASD might exhibit decreased WRI abilities. The classifier with the naive Bayes algorithm outperformed than other four algorithms, and achieved a maximal classification accuracy of 88% and a maximal AUC value of 0.91. Two metrics (i.e., rotation amplitude and symmetry) had high correlations with the gross and fine motor skills [evaluated by Gesell Developmental Schedules-Third Edition and Psychoeducational Profile-3 (PEP-3)]. While, the three metrics had no significant correlation with the visual-motor imitation abilities (evaluated by the subdomain of PEP-3) and the ASD symptom severity [evaluated by the Childhood Autism Rating Scale (CARS)] .

Discussion

The strengths of this study are associated with the low-cost measurement system, correlation between the WRI metrics and clinical measures, decreased WRI abilities in ASD, and high classification accuracy.

Brief Report: Response to Joint Attention and Object Imitation as Predictors of Expressive and Receptive Language Growth Rate in Young Children on the Autism Spectrum

Joint attention and imitation are thought to facilitate a developmental cascade of language and social communication skills. Delays in developing these skills may affect the quality of children's social interactions and subsequent language development. We examined how responding to joint attention and object imitation skills predicted rate of expressive and receptive communication growth rate in a heterogeneous sample of autistic children. Children's baseline skills in responding to joint attention uniquely predicted expressive, but not receptive, language growth rate over time, while object imitation did not significantly predict language growth rate over and above joint attention skills. Future research should examine the potential moderating roles of child age and developmental level in explaining associations between joint attention and object imitation and later language development.

Language acquisition can be truly atypical in autism: Beyond joint attention

Language profiles in autism are variable and atypical, with frequent speech onset delays, but also, in some cases, unusually steep growth of structural language skills. Joint attention is often seen as a major predictor of language in autism, even though low joint attention is a core characteristic of autism, independent of language levels. In this systematic review of 71 studies, we ask whether, in autism, joint attention predicts advanced or only early language skills, and whether it may be independent of language outcomes. We consider only conservative estimates, and flag studies that include heterogenous samples or no control for non-verbal cognition. Our review suggests that joint attention plays a pivotal role for the emergence of language, but is also consistent with the idea that some autistic children may acquire language independently of joint attention skills. We propose that language in autism should not necessarily be modelled as a quantitative or chronological deviation from typical language development, and outline directions to bring autistic individuals' atypicality within the focus of scientific inquiry.

Parent Certainty and Consistency When Completing Vocabulary Checklists in Young Autistic Children

PURPOSE

Using a novel parent report measure, this study investigated whether asking parents to rate their certainty when reporting on child vocabulary skills provided additional insight into parent report and emerging language abilities in young autistic children. Specifically, we investigated whether parent certainty varied based on whether the child was reported to understand, understand and say, or neither understand nor say the word and whether standardized measures of expressive and receptive language abilities and/or autistic traits predicted parent certainty. Lastly, we investigated whether certainty was associated with inconsistency in parent report of child word knowledge.

METHOD

Twenty-one parents and their autistic children ages 2-5 years participated. One parent per child completed the MacArthur-Bates Communicative Development Inventories (MCDI) Words and Gestures form and a custom vocabulary checklist including 24 object nouns from the MCDI. Within the custom form, parents indicated whether their child understood, understood and said, or neither understood nor said 24 target nouns and reported how certain they were about their responses using a 5-point scale. Expressive language, receptive language, and autistic traits were measured via direct assessment using standardized measures.

RESULTS

Parent certainty varied widely and was higher for words the parents reported the children understood and said compared to that for words children either understood or neither understood nor said. Certainty ratings were higher when a child had higher standardized receptive and expressive language scores. Lastly, parent certainty was associated with reporting consistency, clarifying previous findings of inconsistencies in parent report of child vocabulary.

CONCLUSION

Findings from this study indicate that measuring parent certainty provides critical information when assessing early vocabulary skills in autistic children.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.23671497.

Semantic and Syntactic Properties of Words and the Receptive-Expressive Gap in Autistic and Non-Autistic Children

PURPOSE

The goal of this work was to examine the semantic and syntactic properties of the vocabularies of autistic and non-autistic infants and toddlers to see if children in these two groups know different kinds of words. We focused on both receptive and expressive vocabularies. For expressive vocabulary, we looked only at the "active" lexicon: Of those words that are already in children's receptive vocabulary, we asked which ones they also produce.

METHOD

We used an existing data set of 346 parent report vocabulary checklists (MacArthur-Bates Communicative Development Inventory: Words and Gestures) from 41 autistic and 27 non-autistic children at multiple timepoints between the ages of 6 and 43 months. We coded the words on the checklists for various semantic and syntactic properties and evaluated which properties predicted whether children understood and produced those words.

RESULTS

Overall, we replicated a common finding that autistic children have smaller receptive vocabularies than non-autistic children, but we found that of the words they understand, autistic children produce a similar proportion of those words as non-autistic children. While we found that some syntactic properties are more or less likely to be represented in children's early vocabularies (e.g., nouns are more likely to be understood and produced than words that are not nouns), these patterns did not differ across autistic and non-autistic children.

CONCLUSIONS

The semantic and syntactic compositions of autistic and non-autistic children's vocabularies are similar. Thus, while receptive vocabularies are relatively smaller for autistic children, they do not appear to have specific difficulty with words that have particular syntactic or semantic properties, or with adding words to the expressive vocabulary that they already understand.

Early predictors of language skills at 3 years of age vary based on diagnostic outcome: A baby siblings research consortium study

While previous work has identified the early predictors of language skills in infants at elevated familial risk (ER) and low familial risk (LR) for autism spectrum disorder (ASD), no studies to date have explored whether these predictors vary based on diagnostic outcome of ASD or no ASD. The present study used a large, multisite dataset to examine associations between a set of commonly studied predictor variables (infant gesture abilities, fine motor skills, nonverbal cognition, and maternal education level), measured at 12 months, and language skills, measured at 3 years, across three diagnostic outcome groups-infants with ASD ("ASD"), ER infants without ASD ("ER-no ASD"), and LR infants without ASD ("LR-no ASD"). Findings revealed that the predictors of language skills differed across groups, as gesture abilities were positively associated with language skills in the ER-no ASD group but negatively associated with language skills in the ASD group. Furthermore, maternal education level was positively associated with language skills in the ASD and LR-no ASD groups only. Variability in these early predictors may help explain why language skills are heterogeneous across the autism spectrum, and, with further study, may help clinicians identify those in need of additional and/or specialized intervention services that support language development. LAY SUMMARY: The present study identified predictors of language skills in infants with and without autism spectrum disorder (ASD). Maternal education level and 12-month gesture abilities predicted 3-year language skills in infants with ASD. Measuring these predictors early in life may help identify infants and families in need of additional and/or specialized intervention services that support language development.

Word imageability is associated with expressive vocabulary in children with autism spectrum disorder

BACKGROUND & AIMS

Throughout typical development, children prioritize different perceptual, social, and linguistic cues to learn words. The earliest acquired words are often those that are perceptually salient and highly imageable. Imageability, the ease in which a word evokes a mental image, is a strong predictor for word age of acquisition in typically developing (TD) children, independent of other lexicosemantic features such as word frequency. However, little is known about the effects of imageability in children with autism spectrum disorder (ASD), who tend to have differences in linguistic processing and delayed language acquisition compared to their TD peers. This study explores the extent to which imageability and word frequency are associated with early noun and verb acquisition in children with ASD.

METHODS

Secondary analyses were conducted on previously collected data of 156 children (78 TD, 78 ASD) matched on sex and parent-reported language level. Total expressive vocabulary, as measured by the MacArthur Bates Communicative Development Inventory (MB-CDI), included 123 words (78 nouns, 45 verbs) that overlapped with previously published imageability ratings and word input frequencies. A two-step hierarchical linear regression was used to examine the relationship between word input frequency, imageability, and total expressive vocabulary. An F-test was then used to assess the unique contribution of imageability on total expressive vocabulary when controlling for word input frequency.

RESULTS

In both the TD and ASD groups, imageability uniquely explained a portion of the variance in total expressive vocabulary size, independent of word input frequency. Notably, imageability was significantly associated with noun vocabulary and verb vocabulary size alone, with imageability explaining a greater portion of the variance in total nouns produced than in total verbs produced.

CONCLUSIONS

Imageability was identified as a significant lexicosemantic feature for describing expressive vocabulary size in children with ASD. Consistent with literature on TD children, children with ASD who have small vocabularies primarily produce words that are highly imageable. Children who are more proficient word learners with larger vocabularies produce words that are less imageable, indicating a potential shift away from reliance on perceptual-based language processing. This was consistent across both noun and verb vocabularies.

IMPLICATIONS

Our findings contribute to a growing body of literature describing early word learning in children with ASD and provide a basis for exploring the use of multisensory language learning strategies.

Comparing the Pragmatic Speech Profiles of Minimally Verbal and Verbally Fluent Individuals with Autism Spectrum Disorder

Although pragmatic speech impairments have been found across the autism spectrum, how these manifest in minimally verbal (MV) individuals with autism spectrum disorder (ASD) has not been studied. We compared the pragmatic speech profiles of MV (n = 50) and verbally fluent (VF) individuals with ASD (n = 50; 6-21 years-old) based on natural language sampling during the Autism Diagnostic Observation Schedule-2. MV individuals with ASD primarily used their speech to agree/acknowledge/disagree, respond to a question, and request. In contrast, the primary pragmatic function used by VF individuals was commenting. Out of the total non-echolalic speech, groups did not differ proportionally in labeling and response to questions. Findings highlight the importance of investigating multiple aspects of pragmatic communication across different conversational partners and contexts.

Content Words in Child-Directed Speech of Mothers Toward Children With Autism Spectrum Disorder

Purpose Our study aimed to analyze the characteristics of content word usage in mother's child-directed speech ( CDS) toward children with autism spectrum disorder compared to mother's CDS toward typically developing children. Method We analyzed the lexical characteristics of CDS of mothers of children with autism (16 dyads) and compared them from a language developmental perspective to mothers of 20 typical children at the same level of expressive language development. Results Results suggest that mothers of children with autism use equal amounts of content words at the same language level, but the content consists of significantly more concrete nouns and active verbs and rarely the use of abstract nouns, stative verbs, adjectives, and adverbs. Conclusion This study suggests that professionals and parents of children with autism should be aware of the importance of varying their language use of content words.

Examining Useful Spoken Language in a Minimally Verbal Child With Autism Spectrum Disorder: A Descriptive Clinical Single-Case Study

Purpose This was a companion study to a previous one (Biller & Johnson, 2019). The purpose was to develop a detailed descriptive profile of a minimally verbal child with a unique medical history and autism spectrum disorder (ASD). The present report describes his social-cognitive and speech sound production abilities in relation to his potentially burgeoning spoken language. Method This in-depth, descriptive, clinical single-case study focused on a 3-year-old boy who was diagnosed with a chromosomal abnormality and ASD. The size of his spoken vocabulary fell at the upper limit for classifying a child as minimally verbal. His demographic information was obtained, in addition to general information from his mother. Four social-cognitive and three speech sound production abilities were assessed, as well as his overall performance in both domains. The study included a parent interview and two child assessment sessions. Results The child exhibited low social-cognitive and speech sound production abilities for his age, with social-cognitive abilities higher than speech sound production abilities. Comparison with the previous study revealed substantial gaps in social cognition and speech sound production between this child and five other minimally verbal children with ASD. His higher abilities in these two domains co-occurred with his larger spoken vocabulary size. Conclusions Although the child's social-cognitive abilities were low for his age, with his speech sound production abilities even lower, both domains were perhaps high enough to support spoken vocabulary at the upper limit for minimally verbal children. Indeed, there appeared to be quantitative and qualitative differences between him and other minimally verbal children in the previous study. The possibility was explored that there is a point or threshold along the developmental continua for social cognition and speech sound production that allows for expansion into useful language.

An investigation into maternal use of telegraphic input to children with Down syndrome

Maternal input influences language development in children with Down syndrome (DS) and typical development (TD). Telegraphic input, or simplified input violating English grammatical rules, is controversial in speech-language pathology, yet no research to date has investigated whether mothers of children with DS use telegraphic input. This study investigated the quality of linguistic input to children with DS compared to age-matched children with TD, and the relationship between maternal input and child language abilities. Mothers of children with DS simplified their input in multiple ways, by using a lower lexical diversity, shorter utterances, and more telegraphic input compared to mothers of children with TD. Telegraphic input was not significantly correlated with other aspects of maternal input or child language abilities. Since children with DS demonstrate specific deficits in grammatical compared to lexical abilities, future work should investigate the long-term influence of maternal telegraphic input on language development in children with DS.

Concurrent Social Communication Predictors of Expressive Language in Minimally Verbal Children and Adolescents with Autism Spectrum Disorder

Numerous studies have investigated the predictors of language in pre-verbal toddlers and verbally fluent children with autism spectrum disorder (ASD). The present study investigated the concurrent relations among expressive language and a set of empirically-selected social communication variables-joint attention, imitation, and play-in a unique sample of 37 minimally verbal (MV) children and adolescents with ASD. Results revealed that imitation and play were significantly correlated with expressive language, even when controlling for non-verbal IQ, but joint attention was not. Imitation was the only predictor variable to reach significance within the regression model. Findings demonstrate that predictors of expressive language vary for subpopulations of the autism spectrum, and have broader implications for intervention design for older, MV individuals with ASD.

Social-Cognitive and Speech Sound Production Abilities of Minimally Verbal Children With Autism Spectrum Disorders

Purpose To date, there has been a dearth of systematic research that examines both social-cognitive (SC) and speech sound production (SSP) abilities simultaneously in minimally verbal (MV) children with autism spectrum disorders (ASDs). Such an analysis would allow a unified and comprehensive view of the children's communication abilities. The purpose of this study was to develop detailed descriptive profiles of MV children with ASD and uncover patterns in their SC and SSP abilities that may pertain to spoken language. Method This study was a descriptive, multiple clinical case study that examined 5 MV children with ASD, 4 boys and 1 girl, aged 3-6 years. The case studies consisted of demographic information, parent report, and formal and informal assessment of the children. Four SC abilities and 3 SSP abilities were assessed. Results The 5 children's SC score, SSP score, and number of spoken words were converted to z scores. This analysis revealed 2 different patterns of development: 3 of the children had lower SC than SSP abilities, and 2 of the children had the reverse pattern. Conclusions The 5 children were low in both SC and SSP abilities. Although both domains were low, the measure that coincided most with spoken vocabulary among the 5 children was their SSP abilities. Specifically, the children had difficulty in demonstrating emerging control of the onset of voicing for specific speech sounds and verbal imitation of single speech sounds and syllables. Clinical implications of simultaneously assessing and treating SC and SSP abilities in MV children are discussed.

The relation between parent verbal responsiveness and child communication in young children with or at risk for autism spectrum disorder: A systematic review and meta-analysis

Among preschool-age children with autism spectrum disorder (ASD) and typically developing children, parents' verbal responsiveness (PVR) has long been shown to predict children's later language ability. However, before the age of three, when language develops most rapidly, the early social communication deficits associated with ASD may impact parents' opportunities to facilitate early language development. The aim of this review was to characterize the relation between PVR and the vocal communication ability of children with or at high risk for ASD early in development. Specifically, we examined whether the relation between PVR and child communication varied by type of PVR and by child diagnostic status, as well as whether interventions increased PVR. A systematic multi-database search yielded 25 empirical studies (804 parent-toddler dyads; 30 effect sizes) that met inclusion criteria and related a variable of PVR to a variable of child vocalization or language. Meta-regression analyses revealed that the relation between PVR and child communication was significant regardless of PVR type or child diagnostic status. To date, interventions targeting both PVR and child communication were found to significantly increase PVR, but not child communication, for these populations. Future research should examine parent-child communication in a transactional, longitudinal manner. In addition, these findings have implications for interventions designed to target parents' responsiveness and child communication. Autism Research 2019, 12: 715-731. © 2019 International Society for Autism Research, Wiley Periodicals, Inc. LAY SUMMARY: For families with children under 3 years old who are at risk for or diagnosed with ASD, this study revealed empirical evidence of a robust relation between parents'' verbal responsiveness to their children's play and communication and children's communication ability. This relation is similar to that reported in research on typically developing children. Interventions designed to improve parent-child interaction in children with or at risk for ASD may be effective in increasing parents' responsiveness.

The Shape Bias in Children With Autism Spectrum Disorder: Potential Sources of Individual Differences

Purpose

Children with autism spectrum disorder (ASD) demonstrate many mechanisms of lexical acquisition that support language in typical development; however, 1 notable exception is the shape bias. The bases of these children's difficulties with the shape bias are not well understood, and the current study explored potential sources of individual differences from the perspectives of both attentional and conceptual accounts of the shape bias.

Method

Shape bias performance from the dataset of Potrzeba, Fein, and Naigles (2015) was analyzed, including 33 children with typical development (M = 20 months; SD = 1.6), 15 children with ASD with high verbal abilities (M = 33 months; SD = 4.6), and 14 children with ASD with low verbal abilities (M = 33 months; SD = 6.6). Lexical predictors (shape-side noun percentage from the MacArthur-Bates Communicative Development Inventory; Fenson et al., 2007) and social-pragmatic predictors (joint attention duration during play sessions) were considered as predictors of subsequent shape bias performance.

Results

For children in the low verbal ASD group, initiation of joint attention (positively) and passive attention (negatively) predicted subsequent shape bias performance, controlling for initial language and developmental level. Proportion of child's known nouns with shape-defined properties correlated negatively with shape bias performance in the high verbal ASD group but did not reach significance in regression models.

Conclusions

These findings suggest that no single account sufficiently explains the observed individual differences in shape bias performance in children with ASD. Nonetheless, these findings break new ground in highlighting the role of social communicative interactions as integral to understanding specific language outcomes (i.e., the shape bias) in children with ASD, especially those with low verbal abilities, and point to new hypotheses concerning the linguistic content of these interactions.

Presentation Video

https://doi.org/10.23641/asha.7299581.

Longitudinal predictors of early language in infants with Down syndrome: A preliminary study

PURPOSE

Children with Down syndrome (DS) typically have marked delays in language development relative to their general cognitive development, with particular difficulties in expressive compared to receptive language. Although early social communication skills, including gestures and joint attention, have been shown to be related to later language outcomes in DS, knowledge is limited as to whether these factors exclusively predict outcomes, or whether other factors (e.g. perceptual and non-verbal skills) are involved. This study addressed this question.

METHOD

Longitudinal data for a group of infants with DS (n = 14) and a group of typically-developing (TD) infants (n = 35) were collected on measures that have been shown to predict language in TD infants and/or those with developmental delays. These included: non-verbal mental ability, speech segmentation skills, and early social communication skills (initiating and responding to joint attention, initiating behavioural requests).

RESULTS

Linear regression analyses showed that speech segmentation and initiating joint attention were the strongest predictors of later language in the TD group, whereas non-verbal mental ability and responding to joint attention were the strongest predictors of later language for infants with DS.

CONCLUSIONS

Speech segmentation ability may not determine language outcomes in DS, and language acquisition may be more constrained by social communication and general cognitive skills.

Maternal Responsiveness to Gestures in Children With Down Syndrome

PURPOSE

This study compared gesture use in young children with Down syndrome (DS) and typical development (TD) as well as how mothers respond to child gestures based on child age and diagnosis.

METHOD

Twenty-two mother-child dyads with DS and 22 mother-child dyads with TD participated. The child participants were between 22 and 63 months and were matched on chronological age. We coded child gesture use and whether mothers recoded child gestures (i.e., provided a verbal translation) during naturalistic interactions.

RESULTS

The children with DS used more gestures than peers with TD. After controlling for expressive language ability, the two groups were not significantly different on child gesture use. Regardless of child diagnosis, mothers recoded approximately the same percentage of child gestures. There was a significant interaction between child diagnosis and child age when predicting the percentage of maternal gesture recodes; mothers of children with DS did not demonstrate differences in the percentage of maternal gesture recodes based on child age, but there was a negative relationship between the percentage of maternal gesture recodes and child age for the children with TD.

CONCLUSIONS

Young children with DS gesture more than chronological age-matched children with TD, therefore providing numerous opportunities for caregivers to recode child gestures and support language development. Early intervention should focus on increasing parent responsiveness to child gestures earlier in life in order to provide additional word-learning opportunities for children with DS.

Predicting Intentional Communication in Preverbal Preschoolers with Autism Spectrum Disorder

Intentional communication has previously been identified as a value-added predictor of expressive language in preverbal preschoolers with autism spectrum disorder. In the present study, we sought to identify value-added predictors of intentional communication. Of five theoretically-motivated putative predictors of intentional communication measured early in the study (at study entry and 4 months after), three had significant zero-order correlations with later intentional communication (12 months after study entry) and were thus added to a linear model that predicted later intentional communication scores controlling for initial intentional communication scores at study entry. After controlling for initial intentional communication, early motor imitation was the only predictor that accounted for a significant amount of variance in children's later intentional communication.

The impact of autism spectrum disorder symptoms on gesture use in fragile X syndrome and Down syndrome

BACKGROUND & AIMS

This study compared gesture rate and purpose in participants with Down syndrome (DS) and fragile X syndrome (FXS), and the impact of autism spectrum disorder (ASD) symptoms on each syndrome.

METHODS

Twenty individuals with fragile X syndrome and 20 individuals with Down syndrome between nine and 22 years of age participated in this study. We coded gesture rate and purpose from an autism spectrum disorder evaluation, the Autism Diagnostic Observation Schedule - Second Edition.

RESULTS

We did not find between-group differences (Down syndrome compared to fragile X syndrome) in gesture rate or purpose. Notably, as autism spectrum disorder symptoms increased, the group with Down syndrome produced a lower rate of gestures, but used gestures for the same purpose. Gesture rate did not change based on autism spectrum disorder symptoms in the participants with fragile X syndrome, but as autism spectrum disorder symptoms increased, the participants with fragile X syndrome produced a larger proportion of gestures to regulate behavior and a smaller proportion for joint attention/social interaction.

CONCLUSIONS

Overall, the amount or purpose of gestures did not differentiate individuals with Down syndrome and fragile X syndrome. However, the presence of autism spectrum disorder symptoms had a significant and unique impact on these genetic disorders. In individuals with Down syndrome, the presence of more autism spectrum disorder symptoms resulted in a reduction in the rate of gesturing, but did not change the purpose. However, in fragile X syndrome, the rate of gestures remained the same, but the purpose of those gestures changed based on autism spectrum disorder symptoms.

IMPLICATIONS

Autism spectrum disorder symptoms differentially impact gestures in Down syndrome and fragile X syndrome. Individuals with Down syndrome and more autism spectrum disorder symptoms are using gestures less frequently. Therefore, clinicians may need to consider children with Down syndrome demonstrating symptoms of autism spectrum disorder as distinctly different from children with Down syndrome and few to no symptoms of autism spectrum disorder when implementing interventions or therapy techniques. Severity of autism spectrum disorder symptoms in fragile X syndrome affects qualitative gesture use and motivation to communicate through social gestures, which may be an appropriate goal to target in children with fragile X syndrome and heightened autism spectrum disorder symptoms.

The integrity of lexical acquisition mechanisms in autism spectrum disorders: A research review

Research on autism spectrum disorders (ASD) has rapidly expanded in recent years, yielding important developments in both theory and practice. While we have gained important insights into how children with ASD differ from typically developing (TD) children in terms of phenotypic features, less has been learned about if and how development in ASD differs from typical development in terms of underlying mechanisms of change. This article aims to provide a review of processes subserving lexical development in ASD, with the goal of identifying contributing factors to the heterogeneity of language outcomes in ASD. The focus is on available evidence of the integrity or disruption of these mechanisms in ASD, as well as their significance for vocabulary development; topics include early speech perception and preference, speech segmentation, word learning, and category formation. Significant gaps in the literature are identified and future directions are suggested. Autism Res 2016, 9: 810-828. © 2015 International Society for Autism Research, Wiley Periodicals, Inc.

"You're telling me!" The Prevalence and Predictors of Pronoun Reversals in Children with Autism Spectrum Disorders and Typical Development

Social and linguistic explanations have been proposed for pronoun reversals in young typically developing (TD) children and those with autism spectrum disorders (ASD). The current study breaks new ground in investigating both explanations, comparing 18 TD toddlers and 15 children with ASD at similar language levels. Spontaneous speech was sampled every four months for six visits. Vocabulary and joint attention were also measured. Both groups produced pronoun reversals at low rates. The ASD group produced somewhat more reversals than the TD group, overall and at multiple visits. In the ASD group, early language and joint attention scores contributed significantly and independently to the incidence of reversal. Both linguistic and social factors seem implicated; moreover, reversals seem to occur when children's language and social abilities develop asynchronously. These findings can help clinicians devise both linguistic and social interventions for the relevant children.

The effects of embodied rhythm and robotic interventions on the spontaneous and responsive verbal communication skills of children with Autism Spectrum Disorder (ASD): A further outcome of a pilot randomized controlled trial

The current manuscript is the second in a mini-series of manuscripts reporting the effects of alternative, movement-based, rhythm and robotic interventions on the social communication skills of 36 school-age children with ASD. This pilot randomized controlled trial compared the effects of 8-weeks of rhythm and robotic interventions to those of a standard-of-care, comparison intervention. The first manuscript reported intervention effects on the spontaneous and responsive social attention skills of children. In this manuscript, we report intervention effects on the spontaneous and responsive verbal communication skills of children. Communication skills were assessed within a standardized test of responsive communication during the pretest and posttest as well as using training-specific measures of social verbalization during early, mid, and late training sessions. The rhythm and comparison groups improved on the standardized test in the posttest compared to the pretest. The rhythm and robot groups increased levels of social verbalization across training sessions. Movement-based and stationary contexts afforded different types and amounts of communication in children with ASD. Overall, movement-based interventions are a promising tool to enhance verbal and non-verbal communication skills in children with ASD.

Longitudinal prediction of language emergence in infants at high and low risk for autism spectrum disorder

This study used a prospective longitudinal design to examine the early developmental pathways that underlie language growth in infants at high risk (n = 50) and low risk (n = 34) for autism spectrum disorder in the first 18 months of life. While motor imitation and responding to joint attention (RJA) have both been found to predict expressive language in children with autism spectrum disorder and those with typical development, the longitudinal relation between these capacities has not yet been identified. As hypothesized, results revealed that 15-month RJA mediated the association between 12-month motor imitation and 18-month expressive vocabulary, even after controlling for earlier levels of RJA and vocabulary. These results provide new information about the developmental sequencing of skills relevant to language growth that may inform future intervention efforts for children at risk for language delay or other developmental challenges.

The preliminary analysis of the reliability and validity of the Chinese Edition of the CSBS DP

This study marked a preliminary attempt to standardize the Chinese Edition of the Communication and Symbolic Behavior Scales Developmental Profile (Wetherby & Prizant, 2002; CSBS DP) to assist in the early identification of young children with special needs in Taiwan. The study was conducted among 171 infants and toddlers aged 1-2. It also included a follow-up study one year after the initial test. Three domestically developed standardized child development inventories were used to measure the concurrent validity and predictive validity. The Chinese Edition of the CSBS DP demonstrated overall good test-retest and inter-rater reliability. It also showed good concurrent and predictive validity. The current study yields preliminary evidence that the Chinese Edition of the CSBS DP could be a valuable assessment tool worthy of wider distribution. Future research should employ random sampling to establish a true national norm. Additionally, the follow-up study needs to include atypical groups and to expand to children aged 6-12 months to strengthen the applicability of the instrument in Taiwan.

Language development in infants and toddlers with fragile X syndrome: change over time and the role of attention

Fragile X syndrome (FXS) is associated with significant language and communication delays, as well as problems with attention. This study investigated early language abilities in infants and toddlers with FXS (n  =  13) and considered visual attention as a predictor of those skills. We found that language abilities increased over the study period of 9 to 24 months, with moderate correlations among language assessments. In comparison to typically developing infants (n  =  11), language skills were delayed beyond chronological age and developmental-level expectations. Aspects of early visual attention predicted later language ability. Atypical visual attention is an important aspect of the FXS phenotype with implications for early language development, particularly in the domain of vocabulary.

Social smiling and its components in high-risk infant siblings without later ASD symptomatology

Impaired affective expression, including social smiling, is common in children with autism spectrum disorder (ASD), and may represent an early marker for ASD in their infant siblings (Sibs-ASD). Social smiling and its component behaviors (eye contact and non-social smiling) were examined at 15 months in Sibs-ASD who demonstrated later ASD symptomatology (Sibs-ASD/AS), those who did not (Sibs-ASD/NS), and low-risk controls (Sibs-TD). Both Sibs-ASD subgroups demonstrated lower levels of social smiling than Sibs-TD, suggesting that early social smiling may reflect elevated genetic vulnerability rather than a specific marker for ASD. Only the Sibs-ASD/AS demonstrated less eye contact and non-social smiling than Sibs-TD, suggesting that different processes, threshold effects, or protective factors may underlie social smiling development in the two Sibs-ASD subgroups.

Eye tracking as a measure of receptive vocabulary in children with autism spectrum disorders

This study examined the utility of eye tracking research technology to measure speech comprehension in 14 young boys with autism spectrum disorders (ASD) and 15 developmentally matched boys with typical development. Using eye tracking research technology, children were tested on individualized sets of known and unknown words, identified based on their performance on the Peabody Picture Vocabulary Test. Children in both groups spent a significantly longer amount of time looking at the target picture when previous testing indicated the word was known (known condition). Children with ASD spent similar amounts of time looking at the target and non-target pictures when previous testing indicated the word was unknown (unknown condition). However, children with typical development looked longer at the target pictures in the unknown condition as well, potentially suggesting emergent vocabulary knowledge.

What do repetitive and stereotyped movements mean for infant siblings of children with autism spectrum disorders?

Repetitive and stereotyped movements (RSMs) in infancy are associated with later diagnoses of autism spectrum disorder (ASD), yet this relationship has not been fully explored in high-risk populations. The current study investigated how RSMs involving object and body use are related to diagnostic outcomes in infant siblings of children with ASD (Sibs-ASD) and typically developing children (Sibs-TD). The rate and number of different types of RSMs were measured at an average of 15 months with follow-up diagnostic evaluations approximately 18 months later. While Sibs-ASD displayed higher rates of RSMs relative to Sibs-TD, rates did not differ according to diagnostic outcome in Sibs-ASD. However preliminary evidence suggests that qualitative differences in RSM type warrant further investigation as early diagnostic markers.

Understanding goals and intentions in low-functioning autism

We investigated ability to understand goals and attribute intentions in the context of two imitation studies in low-functioning, nonverbal children with autism (L-F CWA), a population that is rarely targeted by research in the domain. Down syndrome children (DSC) and typically developing children (TDC) were recruited to form matched comparison groups. In the two sets of simple action demonstrations only contextual indicators of the model's intentions were manipulated. In the Head touch experiment the model activated a button on a toy by pushing it with the forehead, whereas in the Hidden box experiment the model used a ball with a magnet to lift a box out of its container. Both actions were unusual and non-affordant with regards to the objects involved, none of the children in the baseline condition produced them. L-F CWA imitated the experimenter exactly, regardless of the model's intention. TDC showed appreciation of the model's intention by imitating her actions selectively. DSC reproduced only the intentional action as often as they imitated the experimenter exactly. It is concluded that L-F CWA attributed goals to the observed model, but did not show an appreciation of the model's intentions even in these simplified, nonverbal contexts.

The contribution of two categories of parent verbal responsiveness to later language for toddlers and preschoolers on the autism spectrum

PURPOSE

The authors examined longitudinal associations between 2 categories of parent verbal responsiveness and language comprehension and production 1 year later in 40 toddlers and preschoolers with a diagnosis of an autism spectrum disorder (ASD).

METHOD

Parent-child play samples using a standard toy set were digitally captured and coded for child engagement with objects and communication acts and for parent verbal responses to play and communication.

RESULTS

After controlling for parent education, child engagement, and initial language level, only parent directives for language that followed into the child's focus of attention accounted for unique variance in predicting both comprehension and production 1 year later. A series of exploratory analyses revealed that parent comments that followed into the child's focus of attention also accounted for unique variance in later comprehension and production for children who were minimally verbal at the initial time period.

CONCLUSIONS

Child developmental level may warrant different types of linguistic input to facilitate language learning. Children with ASD who have minimal linguistic skills may benefit from parent language input that follows into the child's focus of attention. Children with ASD who are verbally fluent may need more advanced language input to facilitate language development.

Rating parent-child interactions: joint engagement, communication dynamics, and shared topics in autism, Down syndrome, and typical development

A battery of 17 rating items were applied to video records of typically-developing toddlers and young children with autism and Down syndrome interacting with their parents during the Communication Play Protocol. This battery provided a reliable and broad view of the joint engagement triad of child, partner, and shared topic. Ratings of the child's joint engagement correlated very strongly with state coding of joint engagement and replicated the finding that coordinated joint engagement was less likely in children with autism. Ratings of other child actions, of parent contributions, and of shared topics and communicative dynamics also documented pervasive variations related to diagnosis, language facility, and communicative context.

Common neurological co-morbidities in autism spectrum disorders

PURPOSE OF REVIEW

Autism spectrum disorders (ASDs) are heterogeneous neurodevelopmental disorders associated with various co-morbidities. Neurological co-morbidities include motor impairments, epilepsy, and sleep dysfunction. These impairments have been receiving more attention recently, perhaps because of their significant impact on the behavior and cognitive function of children with ASDs. Here, we review the epidemiology, etiology, and clinical approach to these neurological co-morbidities and highlight future research directions.

RECENT FINDINGS

Motor impairments include stereotypies, motor delays, and deficits, such as dyspraxia, incoordination, and gait problems. Sleep dysfunction typically presents as difficulty with sleep onset and prolonged awakenings during the night. Recent data suggest that abnormalities in melatonin may affect sleep and may be a potential treatment target. There is no classic epilepsy syndrome associated with ASDs. Intellectual disability, syndromic autism, and female sex are specific risk factors. Recent research has focused on identifying the overlapping pathways between these neurological co-morbidities and the core deficits in ASDs, which may have direct and powerful implications for treatment and prognosis.

SUMMARY

Motor impairment, epilepsy, and sleep dysfunction are common neurological co-morbidities in ASDs. Clinicians should be aware that recognition and treatment of these issues may improve the function and outcome of children with ASDs.

Intentional communication in nonverbal and verbal low-functioning children with autism

In this study we characterized profiles of communicative functions and forms of children with autism and intellectual disability (n=26), as compared to typically developing children (n=26) with a comparable nonverbal mental age (2-5 years). Videotapes of the Communication and Symbolic Behavior Scales - Developmental Profile were analyzed using a standardized observation scheme in which three main functions were distinguished: behavior regulation, social interaction, and joint attention. Different forms of communication were also investigated: gestures, vocalizations/verbalizations, and eye gaze. Results indicated that in typically developing children the proportion of communication for the purpose of joint attention was much higher than for behavior regulation, whereas in children with autism the opposite pattern was seen. Low-functioning nonverbal children with autism mainly communicated for behavior regulation and not or only rarely for declarative purposes. Generally, this subgroup used the least complex forms to communicate. Low-functioning verbal children with autism differed from typically developing children only in the rate, not in the proportion of communication for specific functions. Combinations of three different communicative forms were used by verbal children with autism less frequently than by typically developing children.

LEARNING OUTCOMES

After reading this paper, readers should be able to: (1) describe early development of communicative functions, (2) explain differences in communication profiles with respect to form and function between verbal and nonverbal low-functioning children with autism and typically developing children matched on nonverbal mental age and (3) discuss clinical implications of the findings for communication interventions in verbal and nonverbal low-functioning children with autism.

The use of the Bilingual Aphasia Test for assessment and transcranial direct current stimulation to modulate language acquisition in minimally verbal children with autism

Minimally verbal children with autism commonly demonstrate language dysfunction, including immature syntax acquisition. We hypothesised that transcranial direct current stimulation (tDCS) should facilitate language acquisition in a cohort (n = 10) of children with immature syntax. We modified the English version of the Bilingual Aphasia Test (BAT) to test only basic canonical subject-verb-object sentences. We tested syntactic accuracy after teaching then testing all vocabulary from the subsequent syntax test to ensure validity of syntactic scoring. We used scaffolding sentences for syntax training. All procedures were performed both before and after tDCS. Results demonstrated a large effect size of the difference between pre-/post-tDCS groups (p < 0.0005, d = 2.78), indicating syntax acquisition. Combining a modified BAT with tDCS constitutes effective modalities for assessment and treatment of immature syntax in children with autism. Future studies should explore the BAT for patients with an inability to use or understand language, in particular bilingual children with autism.

The neurology of autism spectrum disorders

PURPOSE OF REVIEW

Neurological comorbidities in autism spectrum disorders (ASDs) are not only common, but they are also associated with more clinical severity. This review highlights the most recent literature on three of autism's most prevalent neurological comorbidities: motor impairment, sleep disorders and epilepsy.

RECENT FINDINGS

Motor impairment in ASDs manifests as both delays and deficits, with delays found in gross and fine motor domains and deficits found in praxis, coordination and gait, all of which affect other cognitive and behavioral domains. Sleep disorders, especially insomnia, occur in up to 83% of children with ASDs and recent studies have begun to explore the underlying biochemical and behavioral basis of the impairment, which has bolstered treatment studies. Epilepsy is reported in up to one third of children with ASDs, and new studies have focused on identifying the genetic causes of this association.

SUMMARY

Better characterization of the phenotype, developmental trajectory and underlying pathophysiology of these neurological comorbidities will enable us to define neurological endophenotypes within the autism spectrum. Future studies must investigate the emergence of these comorbidities prospectively in order to determine whether they lie on the causal pathway to ASDs or whether they reflect epiphenomena of the disorder. As epilepsy and sleep disorders can be treated and may contribute significantly to behavioral and cognitive abnormalities in ASDs, their identification is of high clinical relevance.

What Does Teaching Declaratives Tell Us About the Criteria by Which we Can Judge the Developmental Importance of Treatment Outcomes?

This paper uses examples of treatment research on declaratives to illustrate criteria for determining whether a taught behavior is a "skill", not just a context-bound behavior and whether the taught skill has associations with other theoretically linked skills as one type of validation evidence. The paper uses data from three treatment studies to illustrate the issues and proposed criteria. The paper concludes with a call to consumers and producers of treatment research to use the criteria to judge the developmental importance of treatment outcomes.

Characterizing and predicting outcomes of communication delays in infants and toddlers: implications for clinical practice

PURPOSE

This article focuses on using currently available data to assist speech-language pathologists (SLPs) in making decisions regarding a child's eligibility and considerations for recommended "dosage" of early intervention (EI) services.

METHOD

Literature describing the characteristics of infants and toddlers who are likely recipients of EI services was reviewed.

RESULTS

Current literature provides information that can be used to inform clinical decisions for infants and toddlers with established medical conditions, as well as those with risk factors, for oral language, communication, and subsequent literacy disabilities. This information is summarized.

CONCLUSION

Extant literature suggests that EI makes a critical difference in the developmental course of communication as well as in other learning domains for children with a variety of established conditions. The literature also provides guidance to SLPs who must evaluate and weigh risk factors for children with less clear eligibility for services.

Types of parent verbal responsiveness that predict language in young children with autism spectrum disorder

PURPOSE

This study examined short-term predictive associations between 5 different types of parent verbal responsiveness and later spoken vocabulary for 32 young children with a confirmed diagnosis of autism spectrum disorder (ASD).

METHOD

Parent verbal utterances were coded from videotapes of naturalistic parent-child play sessions using interval and event-based coding. A vocabulary difference score, calculated using the MacArthur Communicative Development Inventories (L. Fenson et al., 1993), was used as the outcome measure of spoken vocabulary 6 months later.

RESULTS

Parent follow-in comments and follow-in directives predicted spoken vocabulary after controlling for child engagement. Parent expansions of child verbal utterances predicted spoken vocabulary after controlling for child talkativeness. When entered together into a regression analysis, metrics that represented (a) the number of parent utterances following into the child's focus of attention and (b) the number of parent utterances responding to child verbal communication acts both accounted for unique variance in predicting change in spoken vocabulary from Time 1 to Time 2.

CONCLUSION

Parent verbal utterances that follow into the child's current focus of attention or respond to child verbal communication acts may facilitate the process of early vocabulary acquisition by mitigating the need for children with ASD to use attention-following as a word-learning strategy.

Estudo longitudinal da atenção compartilhada em crianças autistas não-verbais

OBJETIVO: identificar e caracterizar as habilidades e o desenvolvimento da Atenção Compartilhada de crianças autistas, não-verbais, pela observação de comportamentos comunicativos. MÉTODOS: a pesquisa envolveu cinco meninos, entre 5a,9m e 8a,6m, com diagnóstico de Transtorno Autista (DSM-IV, 2002), filmados em dois momentos, com intervalo de 4 meses. Neste período, as crianças foram submetidas à intervenção fonoaudiológica baseada na estimulação da Atenção Compartilhada. Cada gravação era de 15 minutos e envolvia uma criança ou um grupo de 2-3 crianças com a terapeuta, em situações de interação não-dirigida e semi-dirigida, na escola onde estudavam. Foram observados e registrados comportamentos referentes às habilidades de Atenção Compartilhada. O material utilizado envolveu instrumentos musicais de percussão. Os dados foram analisados considerando-se o tempo, a interação e o(s) interlocutor(es). RESULTADOS: o comportamento olhar apresentou maior crescimento em cada um dos sujeitos. A análise dos dados revelou que os sujeitos apresentaram tendências qualitativas de evolução da habilidade de compartilhar a atenção, revelando um significado clínico importante, apesar da não ocorrência de significância estatística. Cada sujeito apresentou características e evolução dos Comportamentos Comunicativos relativos à Atenção Compartilhada de maneira individualizada. Após o período de intervenção fonoaudiológica, verificou-se aumento quantitativo dos comportamentos observados nos cinco sujeitos, principalmente na interação criança-terapeuta. CONCLUSÕES: o olhar é um importante patamar para o desenvolvimento dos outros comportamentos em direção à Atenção Compartilhada. A interação adulto-criança favorece o surgimento de comportamentos comunicativos e o compartilhar. A terapia fonoaudiológica focada nas habilidades de Atenção Compartilhada parece contribuir positivamente para o desenvolvimento da comunicação das crianças autistas.

Predicting social impairment and ASD diagnosis in younger siblings of children with autism spectrum disorder

Later-born siblings of children with autism spectrum disorder (Sibs-ASD) are at elevated risk for social impairments. Two putative predictors of later social impairment-measures of responding to joint attention and weighted triadic communication-were examined in a sample of 43 Sibs-ASD who were followed from 15 to 34 months of age. Results revealed that initial level of responding to joint attention and growth rate of weighted triadic communication predicted the degree of social impairment at the final measurement period. Additionally, both predictors were associated with later ASD diagnosis. In contrast, unweighted triadic communication, age of entry into the study, and initial language level did not predict later social impairment. The importance of considering social outcome as a continuous variable in prospective studies of Sibs-ASD is discussed.