Play in Relation to Autism Traits in Young Children at Elevated Likelihood for Autism Spectrum Disorder.

Play of younger siblings of children with autism spectrum disorder (ASD) (siblings; n = 44), very preterm children (preterms; n = 44), and children at typical likelihood for ASD (n = 36) was observed at 24 months. Children with ASD and atypical development engaged less in spontaneous (pre-)symbolic play than typically developing children. Total duration of spontaneous and elicited (pre-)symbolic play was associated with later ASD traits in siblings. However, no association between most play variables and ASD traits was found in preterms. This suggests possible different ASD-trajectories between siblings and preterms. Thus, spontaneous (pre-)symbolic play may be indicative of developmental challenges across several populations, and results highlight the need to move beyond studying only siblings in order to broaden our understanding of ASD.

Emerging Verbal Functions in Early Infancy: Lessons from Observational and Computational Approaches on Typical Development and Neurodevelopmental Disorders.

Objectives: Research on typically developing (TD) children and those with neurodevelopmental disorders and genetic syndromes was targeted. Specifically, studies on autism spectrum disorder, Down syndrome, Rett syndrome, fragile X syndrome, cerebral palsy, Angelman syndrome, tuberous sclerosis complex, Williams-Beuren syndrome, Cri-du-chat syndrome, Prader-Willi syndrome, and West syndrome were searched. The objectives are to review observational and computational studies on the emergence of (pre-)babbling vocalisations and outline findings on acoustic characteristics of early verbal functions. Methods: A comprehensive review of the literature was performed including observational and computational studies focusing on spontaneous infant vocalisations at the pre-babbling age of TD children, individuals with genetic or neurodevelopmental disorders. Results: While there is substantial knowledge about early vocal development in TD infants, the pre-babbling phase in infants with neurodevelopmental and genetic syndromes is scarcely scrutinised. Related approaches, paradigms, and definitions vary substantially and insights into the onset and characteristics of early verbal functions in most above-mentioned disorders are missing. Most studies focused on acoustic low-level descriptors (e.g. fundamental frequency) which bore limited clinical relevance. This calls for computational approaches to analyse features of infant typical and atypical verbal development. Conclusions: Pre-babbling vocalisations as precursor for future speech-language functions may reveal valuable signs for identifying infants at risk for atypical development. Observational studies should be complemented by computational approaches to enable in-depth understanding of the developing speech-language functions. By disentangling features of typical and atypical early verbal development, computational approaches may support clinical screening and evaluation.

Urine lactate concentration as a non-invasive screener for metabolic abnormalities: Findings in children with autism spectrum disorder and regression.

There is increasing evidence that diseases caused by dysfunctional mitochondria (MD) are associated with autism spectrum disorder (ASD). A comprehensive meta-analysis showed that developmental regression was reported in half of the children with ASD and mitochondrial dysfunction which is much higher than in the general population of ASD. The aim of the present exploratory study was to determine lactate concentrations in urine of children with ASD, as a non-invasive large-scale screening method for metabolic abnormalities including mitochondrial dysfunction and its possible association with regression. First, clinical characteristics of MD were examined in 99 children (3-11 years) with ASD. Second, clinical characteristics of MD, severity of ASD and reported regression were compared between children with the 20% lowest lactate concentrations and those with the 20% highest lactate concentrations in urine. Third, clinical characteristics of MD and lactate concentration in urine were compared in children with (n = 37) and without (n = 62) reported regression. An association of urine lactate concentrations with mitochondrial dysfunction and regression could not be demonstrated in our large ASD cohort. However, since ASD children were reported by their parents to show a broad range of phenotypic characteristics of MD (e.g., gastro-intestinal and respiratory impairments), and lactate concentrations in urine are not always increased in individuals with MD, the presence of milder mitochondrial dysfunction cannot be excluded. Development of alternative biomarkers and their implementation in prospective studies following developmental trajectories of infants at elevated likelihood for ASD will be needed in the future to further unravel the association of ASD with mitochondrial dysfunction and eventually improve early detection.

The impact of COVID-19 measures on parent-reported restricted and repetitive behaviours in pre-school children with autism.

Background: COVID-19 restrictive measures have had a considerable impact on daily life routines, which may be especially challenging for families of children with autism. In pre-schoolers with autism, it is likely that the disruption of routines mainly impacts the presence of restrictive and repetitive behaviours (RRBs). Furthermore, influence of comorbid conditions, secondary behavioural difficulties and home environment characteristics on RRBs was explored. Method: A cross-sectional online survey design was used to collect parent-report data on 254 children with autism (2.5-6 years) during lockdown in the early months of the pandemic. RRBs were assessed using the Repetitive Behaviour Scale-Revised (RBS-R). Results: Parents reported a significant increase in stereotypic, self-injurious, compulsive and ritualistic behaviour, and restricted interests after implementation of COVID-19 restrictions. The presence of a co-occurring condition, such as language impairments or intellectual disability, was associated with more self-injurious and stereotypic behaviour. However, there was no effect of home environment on RRBs. Further, most children showed increases in internalising and/or externalising behaviour. Increased inattentive behaviour was associated with more ritualistic and stereotypic behaviour, and restricted interests. Decreases in hyperactivity were related to more restricted interests. Importantly, in a subset of children, parents reported less behavioural difficulties during the lockdown. Conclusions: Findings highlight the importance of flexible implementation and continuity of care for pre-schoolers with autism and support for parents. Further follow-up of children with autism and RRBs, and co-occurring behavioural difficulties is needed and could enhance our understanding of the long-term effects associated with sudden restrictive measures to daily routines.

Declining Gaze to Faces in Infants Developing Autism Spectrum Disorder: Evidence From Two Independent Cohorts.

Two independent cohorts (N = 155, N = 126) of infants at high and low risk for autism spectrum disorder (ASD) were followed prospectively between 6 and 36 months of age, when n = 46 were diagnosed with ASD. Gaze to adult faces was coded-during a developmental assessment (Cohort 1) or a play interaction (Cohort 2). Across both cohorts, most children developing ASD showed sharp declines in gaze to faces over time, relative to children without ASD. These findings suggest that declining developmental trajectories may be more common than previously recognized by retrospective methods. Trajectory-based screening methods could potentially identify children in the early stages of symptom onset and allow for early intervention before the full disorder has developed.

Validation of the Language ENvironment Analysis (LENA) system for Dutch.

The validity of the Language ENvironment Analysis (LENA) System was evaluated for Dutch. 216 5-min samples (six samples per age per child) were selected from daylong recordings at 5, 10 and 14 months of age of native Dutch-speaking younger siblings of children with autism spectrum disorder (N = 6) and of typically developing children (N = 6). Two native Dutch-speaking coders counted the amount of adult words (AWC), child vocalisations (CVC) and conversational turns (CT). Consequently, correlations between LENA and human estimates were explored. Correlations were high for AWC at all ages (r = .73 to .81). Regarding CVC, estimates were moderately correlated at 5 months (r = .57) but the correlation decreased at 10 (r = .37) and 14 months (r = .14). Correlations for CT were low at all ages (r = .19 to .28). Lastly, correlations were not influenced by the risk status of the children.

Characteristics, Early Development and Outcome of Parent-Reported Regression in Autism Spectrum Disorder.

This study explored regression patterns in 100 children with ASD (3-11 years) using several approaches to enhance the validity of retrospective parent report. Both early development and outcome were examined in regression groups defined by 36 months age cut-off and two underlying empirical patterns based on type and onset age. Results over regression groups were generally consistent. During early development, children with regression showed a similar amount of social atypicalities and stereotyped behaviour as compared to children without regression. However, parents indicated less communication skills which could be a valuable predictor of regression. Development after regression was characterised by early language delay and more restricted and repetitive behaviour. The findings provide insight into the diagnosis and prognosis of regression in ASD.

Language growth in very young siblings at risk for autism spectrum disorder.

BACKGROUND: Children with autism spectrum disorder (ASD) show substantial variability in their language development. Language problems are highly prevalent in these children. In addition, the quality of early language abilities contributes to the overall development of these children and is highly predictive of their adult outcome. Yet, little is known about language development in children at risk of ASD during the first years of life. AIMS: To compare early receptive language (RL) and expressive language (EL) development in children at risk of ASD and determine predictors of language development. METHODS & PROCEDURES: Developmental trajectories of RL and EL were investigated from 10 to 36 months of age in younger siblings of typically developing children (LR-sibs, N = 30) and in younger siblings of children with ASD (HR-sibs, N = 31) using the Mullen Scales of Early Learning. Furthermore, both child and demographic characteristics were examined as possible predictors of language development. OUTCOMES & RESULTS: Both groups showed similar growth curves for RL and EL and the majority of the children showed average (within ±1.5 SD of the mean) or above-average language abilities. Nevertheless, the mean growth of EL was lower and the variation in growth of both RL and EL was higher in HR-sibs than in LR-sibs. Furthermore, early child characteristics were predictive of language development in both groups. Yet, some child characteristics seemed to be of more importance in HR-sibs than in LR-sibs. Consequently, lower non-verbal abilities at 10 months in both groups and a higher degree of ASD characteristics at 14 months in HR-sibs may be indicative of difficulties in language development. CONCLUSIONS & IMPLICATIONS: HR-sibs show more variation in their language development than LR-sibs during the first 3 years of life. The majority of HR-sibs, however, did not present with below-average language abilities. Yet, early characteristics of ASD may be a red flag for difficulties in the language development of HR-sibs.

Regression in autism spectrum disorder: A critical overview of retrospective findings and recommendations for future research.

Historically, two onset patterns in autism spectrum disorder (ASD) were described: early onset of symptoms and regression in which one-third appear to show a loss of previously established skills in the second year of life. Since this phenomenon could represent a distinct ASD subtype and provide more insight into the etiology, diagnosis, and prognosis, many studies have compared these two groups. The present review discusses definitions, etiology, and methods used in research with a retrospective design and provides an overview of the results on early development and outcomes. However, retrospective research has not provided clear answers on regression as a distinct subtype of ASD and the historic division between early onset and regression does not seem to fit the empirical findings. Based on inconsistent results, future research on onset patterns in ASD needs to be more systematic on the definitions and methods used. Several recommendations to enhance the reliability of future retrospective results are discussed. The combination of a categorical and dimensional approach provides a new interesting framework.

Social Interactions Between 24-Month-Old Children and Their Older Sibling with Autism Spectrum Disorder: Characteristics and Association with Social-Communicative Development.

This study compared sibling interactions between 24-month-old children and their older sibling with ASD (high-risk; n = 24) with 24-month-old children and their typically developing older sibling (low-risk; n = 32). First, high-risk sibling pairs showed lower levels of positive behaviour and younger siblings of children with ASD imitated their older sibling less. Second, in the high-risk group positive interactions were positively associated with the youngest child's language abilities. However, this association was no longer significant after controlling for language abilities at 14 months. Third, more total interactions in the high-risk group, both negative and positive, were associated with more ASD characteristics. Thus, early sibling interactions might reveal interesting information in light of the (atypical) developmental trajectories of younger siblings of children with ASD.