Kristelle Hudry

Parent-mediated communication-focused treatment in children with autism (PACT): a randomised controlled trial

Summary Background Results of small trials suggest that early interventions for social communication are effective for the treatment of autism in children. We therefore investigated the efficacy of such an intervention in a larger trial. Methods Children with core autism (aged 2 years to 4 years and 11 months) were randomly assigned in a one-to-one ratio to a parent-mediated communication-focused (Preschool Autism Communication Trial [PACT]) intervention or treatment as usual at three specialist centres in the UK. Those assigned to PACT were also given treatment as usual. Randomisation was by use of minimisation of probability in the marginal distribution of treatment centre, age (≤42 months or >42 months), and autism severity (Autism Diagnostic Observation Schedule-Generic [ADOS-G] algorithm score 12–17 or 18–24). Primary outcome was severity of autism symptoms (a total score of social communication algorithm items from ADOS-G, higher score indicating greater severity) at 13 months. Complementary secondary outcomes were measures of parent-child interaction, child language, and adaptive functioning in school. Analysis was by intention to treat. This study is registered as an International Standard Randomised Controlled Trial, number ISRCTN58133827. Results 152 children were recruited. 77 were assigned to PACT (London [n=26], Manchester [n=26], and Newcastle [n=25]); and 75 to treatment as usual (London [n=26], Manchester [n=26], and Newcastle [n=23]). At the 13-month endpoint, the severity of symptoms was reduced by 3·9 points (SD 4·7) on the ADOS-G algorithm in the group assigned to PACT, and 2·9 (3·9) in the group assigned to treatment as usual, representing a between-group effect size of −0·24 (95% CI −0·59 to 0·11), after adjustment for centre, sex, socioeconomic status, age, and verbal and non-verbal abilities. Treatment effect was positive for parental synchronous response to child (1·22, 0·85 to 1·59), child initiations with parent (0·41, 0·08 to 0·74), and for parent-child shared attention (0·33, −0·02 to 0·68). Effects on directly assessed language and adaptive functioning in school were small. Interpretation On the basis of our findings, we cannot recommend the addition of the PACT intervention to treatment as usual for the reduction of autism symptoms; however, a clear benefit was noted for parent-child dyadic social communication. Funding UK Medical Research Council, and UK Department for Children, Schools and Families.

ArticlesParent-mediated communication-focused treatment in children with autism (PACT): a randomised controlled trial

Summary Background Results of small trials suggest that early interventions for social communication are effective for the treatment of autism in children. We therefore investigated the efficacy of such an intervention in a larger trial. Methods Children with core autism (aged 2 years to 4 years and 11 months) were randomly assigned in a one-to-one ratio to a parent-mediated communication-focused (Preschool Autism Communication Trial [PACT]) intervention or treatment as usual at three specialist centres in the UK. Those assigned to PACT were also given treatment as usual. Randomisation was by use of minimisation of probability in the marginal distribution of treatment centre, age (≤42 months or >42 months), and autism severity (Autism Diagnostic Observation Schedule-Generic [ADOS-G] algorithm score 12–17 or 18–24). Primary outcome was severity of autism symptoms (a total score of social communication algorithm items from ADOS-G, higher score indicating greater severity) at 13 months. Complementary secondary outcomes were measures of parent-child interaction, child language, and adaptive functioning in school. Analysis was by intention to treat. This study is registered as an International Standard Randomised Controlled Trial, number ISRCTN58133827. Results 152 children were recruited. 77 were assigned to PACT (London [n=26], Manchester [n=26], and Newcastle [n=25]); and 75 to treatment as usual (London [n=26], Manchester [n=26], and Newcastle [n=23]). At the 13-month endpoint, the severity of symptoms was reduced by 3·9 points (SD 4·7) on the ADOS-G algorithm in the group assigned to PACT, and 2·9 (3·9) in the group assigned to treatment as usual, representing a between-group effect size of −0·24 (95% CI −0·59 to 0·11), after adjustment for centre, sex, socioeconomic status, age, and verbal and non-verbal abilities. Treatment effect was positive for parental synchronous response to child (1·22, 0·85 to 1·59), child initiations with parent (0·41, 0·08 to 0·74), and for parent-child shared attention (0·33, −0·02 to 0·68). Effects on directly assessed language and adaptive functioning in school were small. Interpretation On the basis of our findings, we cannot recommend the addition of the PACT intervention to treatment as usual for the reduction of autism symptoms; however, a clear benefit was noted for parent-child dyadic social communication. Funding UK Medical Research Council, and UK Department for Children, Schools and Families.

Preschoolers with autism show greater impairment in receptive compared with expressive language abilities

BACKGROUND In early typical language development, children understand words before they are able to use them in speech. Children with autism spectrum disorders (ASD) generally show impairments in both the comprehension and the production of language. However, the relative degree of delay or impairment in each of these sub-domains may also be atypical and remains less well-understood. AIMS Relative delay in receptive and expressive language skills was examined within a large sample of preschoolers with autism. Childrens language abilities varied from pre-verbal to fluent speech. METHOD & PROCEDURES Scores on one direct clinician assessment and two parent-report measures of language were obtained for 152 preschoolers with core autism. OUTCOMES & RESULTS As expected, on average, the language ability of the children with autism was lower than typical age norms, albeit with substantial individual variability. On all three language measures, receptive ability was relatively more impaired than expressive ability. Higher non-verbal ability was associated with such an atypical language profile. CONCLUSIONS & IMPLICATIONS Recognition of the marked receptive language impairment relative to expressive language, found to affect at least one-third of preschoolers with autism in this sample, has important implications for interacting with these children and for informing appropriate targets in language and communication intervention.

The development of face orienting mechanisms in infants at-risk for autism

Highlights ► Infants preferentially orient to socially relevant information such as faces. ► Infants at-risk for autism have a tendency to sustain attention to faces. ► Those infants who later develop autism show an equally strong face orienting response. ► Combined influence of social and attentional brain systems is implicated in autism.

Atypicalities in Cortical Structure, Handedness, and Functional Lateralization for Language in Autism Spectrum Disorders

Language is typically a highly lateralized function, with atypically reduced or reversed lateralization linked to language impairments. Given the diagnostic and prognostic role of impaired language for autism spectrum disorders (ASDs), this paper reviews the growing body of literature that examines patterns of lateralization in individuals with ASDs. Including research from structural and functional imaging paradigms, and behavioral evidence from investigations of handedness, the review confirms that atypical lateralization is common in people with ASDs. The evidence indicates reduced structural asymmetry in fronto-temporal language regions, attenuated functional activation in response to language and pre-linguistic stimuli, and more ambiguous (mixed) hand preferences, in individuals with ASDs. Critically, the evidence emphasizes an intimate relationship between atypical lateralization and language impairment, with more atypical asymmetries linked to more substantive language impairment. Such evidence highlights opportunities for the identification of structural and functional biomarkers of ASDs, affording the potential for earlier diagnosis and intervention implementation.

Superior discrimination of speech pitch and its relationship to verbal ability in autism spectrum disorders

Whilst hypersensitivity to pitch information appears to be characteristic of many individuals with autism spectrum disorders little is known about the implications of such a tendency for language acquisition and development. Discrimination of systematically varied pitch differences between pairs of words, nonwords, and nonspeech pitch contour analogues was assessed in children with autism spectrum disorders (ASD) and matched controls. The findings revealed superior performance in ASD, although, like controls, discrimination of pitch in speech stimuli was poorer in this group than for nonspeech stimuli. Whilst it was hypothesized that enhanced processing of speech pitch would correlate negatively with receptive language skills in ASD, the findings did not fully support this, and enhanced discrimination skills were observed in individuals without significant language impairment. The implications of these findings for understanding heterogeneity of language ability in ASD are discussed.

Motor development in children at risk of autism: A follow-up study of infant siblings:

Recently, evidence of poor or atypical motor skills in autism spectrum disorder has led some to argue that motor impairment is a core feature of the condition. The current study uses a longitudinal prospective design to assess the development of motor skills of 20 children at increased risk of developing autism spectrum disorder, who were recruited and tested at 9 and 40 months of age, on the basis of having an older sibling diagnosed with the condition. All children completed a range of motor, face processing, IQ and diagnostic assessments at a follow-up visit (aged 5–7 years), providing a detailed profile of development in this group from a number of standardised, parental report and experimental measures. A higher proportion of children than expected demonstrated motor difficulties at the follow-up visit and those highlighted by parental report as having poor motor skills as infants and toddlers were also more likely to have lower face processing scores and elevated autism-related social symptoms at 5–7 years, despite having similar IQ levels. These data lend support to the argument that early motor difficulties may be a risk factor for later motor impairment as well as differences in social communication and cognition, traits that are related to autism spectrum disorder.

Treatment mechanism in the MRC preschool autism communication trial: implications for study design and parent-focussed therapy for children.

BACKGROUND The PACT randomised-controlled trial evaluated a parent-mediated communication-focused treatment for children with autism, intended to reduce symptom severity as measured by a modified Autism Diagnostic Observation Schedule-Generic (ADOS-G) algorithm score. The therapy targeted parental behaviour, with no direct interaction between therapist and child. While nonsignificant group differences were found on ADOS-G score, significant group differences were found for both parent and child intermediate outcomes. This study aimed to better understand the mechanism by which the PACT treatment influenced changes in child behaviour though the targeted parent behaviour. METHODS Mediation analysis was used to assess the direct and indirect effects of treatment via parent behaviour on child behaviour and via child behaviour on ADOS-G score. Alternative mediation was explored to study whether the treatment effect acted as hypothesised or via another plausible pathway. Mediation models typically assume no unobserved confounding between mediator and outcome and no measurement error in the mediator. We show how to better exploit the information often available within a trial to begin to address these issues, examining scope for instrumental variable and measurement error models. RESULTS Estimates of mediation changed substantially when account was taken of the confounder effects of the baseline value of the mediator and of measurement error. Our best estimates that accounted for both suggested that the treatment effect on the ADOS-G score was very substantially mediated by parent synchrony and child initiations. CONCLUSIONS The results highlighted the value of repeated measurement of mediators during trials. The theoretical model underlying the PACT treatment was supported. However, the substantial fall-off in treatment effect highlighted both the need for additional data and for additional target behaviours for therapy.

Gaze Following, Gaze Reading, and Word Learning in Children at Risk for Autism

This study investigated gaze-following abilities as a prerequisite for word learning, in a population expected to manifest a wide range of social and communicative skills-children with a family history of autism. Fifty-three 3-year-olds with or without a family history of autism took part in a televised word-learning task. Using an eye-tracker to monitor childrens gaze behavior, it was shown that the ability to follow gaze was necessary but not sufficient for successful word learning. Those children who had poor social and communicative skills followed gaze to the labeled object but did not then learn the associated word. These findings shed light on the conditions that lead to successful word learning in typical and atypical populations.

Intellectual development in Autism Spectrum Disorders : new insights from longitudinal studies.

The presence/absence of Intellectual Disability (ID) is considered to be the most critical factor affecting outcomes in individuals with Autism Spectrum Disorders (ASD). However, the question of the specific nature of ID in ASD has received little attention, with the current view being that ID is a comorbid condition (i.e., one that is unrelated in etiology and causality from the ASD itself). Recent advances in developmental neuroscience, highlighting the importance of early exposure to social experiences for cognitive development, support an alternative view; that ID in ASD might emerge as a consequence of severe social-communication deficits on the experience-dependent mechanisms underlying neurocognitive development. We tested this prediction in two independent samples of young children with ASD (Ns = 23 and 60), finding that children with greater ASD severity at an initial assessment were more likely to present with poorer cognitive outcomes at a later assessment, irrespective of initial cognitive level. The results of this proof of principle study suggest that ASD symptom severity contributes to the extent to which the environmental input required to support “typical” brain development can be processed by the individual, so that the risk of developing ID increases as the number and severity of ASD social-communicative impairments increase.