A longitudinal comparison of emotional, behavioral and attention problems in autistic and typically developing children.

BACKGROUND: Mental health problems are elevated in autistic individuals but there is limited evidence on the developmental course of problems across childhood. We compare the level and growth of anxious-depressed, behavioral and attention problems in an autistic and typically developing (TD) cohort. METHODS: Latent growth curve models were applied to repeated parent-report Child Behavior Checklist data from age 2-10 years in an inception cohort of autistic children (Pathways, N = 397; 84% boys) and a general population TD cohort (Wirral Child Health and Development Study; WCHADS; N = 884, 49% boys). Percentile plots were generated to quantify the differences between autistic and TD children. RESULTS: Autistic children showed elevated levels of mental health problems, but this was substantially reduced by accounting for IQ and sex differences between the autistic and TD samples. There was small differences in growth patterns; anxious-depressed problems were particularly elevated at preschool and attention problems at late childhood. Higher family income predicted lower base-level on all three dimensions, but steeper increase of anxious-depressed problems. Higher IQ predicted lower level of attention problems and faster decline over childhood. Female sex predicted higher level of anxious-depressed and faster decline in behavioral problems. Social-affect autism symptom severity predicted elevated level of attention problems. Autistic girls' problems were particularly elevated relative to their same-sex non-autistic peers. CONCLUSIONS: Autistic children, and especially girls, show elevated mental health problems compared to TD children and there are some differences in predictors. Assessment of mental health should be integrated into clinical practice for autistic children.

Service utilization in a sample of preschool children with autism spectrum disorder: A Canadian snapshot.

OBJECTIVE: To describe services received by preschool children diagnosed with autism spectrum disorder (ASD) during the five-year period following their diagnosis. METHOD: An inception cohort of preschoolers diagnosed with ASD from Halifax (Nova Scotia), Montreal (Quebec), Hamilton (Ontario), Edmonton (Alberta) and Vancouver (British Columbia) were invited to participate. Parents/caregivers (n=414) described the services provided to their children at four time points: baseline (T1; within four months of diagnosis; mean age three years); six months later (T2); 12 months later (T3); and at school entry (T4). Data were first coded into 11 service types and subsequently combined into four broader categories (no services, behavioural, developmental and general) for analysis. RESULTS: More than 80% of children at T1, and almost 95% at T4 received some type of service, with a significant number receiving >1 type of service at each assessment point. At T1, the most common service was developmental (eg, speech-language therapy). Subsequently, the most common services were a combination of behavioural and developmental (eg, intensive therapy based on applied behaviour analysis and speech-language therapy). Service provision varied across provinces and over time. DISCUSSION: Although most preschool children with ASD residing in urban centres were able to access specialized services shortly after diagnosis, marked variation in services across provinces remains a concern.

OBJECTIF: Décrire les services qu'ont reçus des enfants d'âge préscolaire ayant un trouble du spectre autistique (TSA) pendant la période de cinq ans suivant leur diagnostic. MÉTHODOLOGIE: Une cohorte initiale d'enfants d'âge préscolaire ayant un TSA diagnostiqué et qui provenaient de Halifax (Nouvelle-Écosse), de Montréal (Québec), de Hamilton (Ontario), d'Edmonton (Alberta) ou de Vancouver (Colombie-Britannique) a été invitée à participer à l'étude. Les parents et les tuteurs (n=414) ont décrit les services fournis à leur enfant à quatre moments : au début (T1; dans les quatre mois suivant le diagnostic, âge moyen de trois ans); six mois plus tard (T2); 12 mois plus tard (T3) et à l'entrée à l'école (T4). Les chercheurs ont d'abord codé les données en 11 types de services, pour ensuite les regrouper en quatre catégories plus vastes (absence de services, comportementaux, développementaux et généraux) en vue de leur analyse. RÉSULTATS: Plus de 80 % des enfants ont reçu certains services à T1, et près de 95 % à T4, et un nombre significatif a reçu plus d'un type de services à chaque évaluation. À T1, le service le plus courant était de type développemental (p. ex., orthophonie). Par la suite, les services les plus courants étaient un mélange de services comportementaux et développementaux (p. ex., thérapie intensive selon l'analyse de comportement appliquée et orthophonie). La prestation des services variait selon les provinces et au fil du temps. EXPOSÉ: Même si la plupart des enfants d'âge préscolaire ayant un TSA qui habitaient dans un centre urbain avaient accès à des services spécialisés peu après le diagnostic, les variations marquées des services entre les provinces demeurent préoccupantes.

The subcortical correlates of autistic traits in school-age children: a population-based neuroimaging study.

BACKGROUND: There is emerging evidence that the neuroanatomy of autism forms a spectrum which extends into the general population. However, whilst several studies have identified cortical morphology correlates of autistic traits, it is not established whether morphological differences are present in the subcortical structures of the brain. Additionally, it is not clear to what extent previously reported structural associations may be confounded by co-occurring psychopathology. To address these questions, we utilised neuroimaging data from the Adolescent Brain Cognitive Development Study to assess whether a measure of autistic traits was associated with differences in child subcortical morphology, and if any observed differences persisted after adjustment for child internalising and externalising symptoms. METHODS: Our analyses included data from 7005 children aged 9-10 years (female: 47.19%) participating in the Adolescent Brain Cognitive Development Study. Autistic traits were assessed using scores from the Social Responsiveness Scale (SRS). Volumes of subcortical regions of interest were derived from structural magnetic resonance imaging data. RESULTS: Overall, we did not find strong evidence for an association of autistic traits with differences in subcortical morphology in this sample of school-aged children. Whilst lower absolute volumes of the nucleus accumbens and putamen were associated with higher scores of autistic traits, these differences did not persist once a global measure of brain size was accounted for. LIMITATIONS: It is important to note that autistic traits were assessed using the SRS, of which higher scores are associated with general behavioural problems, and therefore may not be wholly indicative of autism-specific symptoms. In addition, individuals with a moderate or severe autism diagnosis were excluded from the ABCD study, and thus, the average level of autistic traits will be lower than in the general population which may bias findings towards the null. CONCLUSIONS: These findings from our well-powered study suggest that other metrics of brain morphology, such as cortical morphology or shape-based phenotypes, may be stronger candidates to prioritise when attempting to identify robust neuromarkers of autistic traits.

Severity of hyperacusis predicts individual differences in speech perception in Williams Syndrome.

BACKGROUND: Williams Syndrome (WS) is a neurodevelopmental disorder of genetic origin, characterised by relative proficiency in language in the face of serious impairment in several other domains. Individuals with WS display an unusual sensitivity to noise, known as hyperacusis. METHODS: In this study, we examined the extent to which hyperacusis interferes with the perception of speech in children and adults with WS. Participants were required to discriminate words which differed in one consonant of a cluster when these contrasts were embedded in a background of noise. RESULTS: Although the introduction of noise interfered with performance on a consonant cluster discrimination task equally in the WS and control groups, the severity of hyperacusis significantly predicted individual variability in speech perception within the WS group. CONCLUSIONS: These results suggest that alterations in sensitivity to input mediate atypical pathways for language development in WS, where hyperacusis exerts an important influence together with other non-auditory factors.

Non-verbal IQ and change in restricted and repetitive behavior throughout childhood in autism: a longitudinal study using the Autism Diagnostic Interview-Revised.

BACKGROUND: Restricted and repetitive behavior (RRB) is one of the characteristic features of Autism Spectrum Disorder. This domain of symptoms includes a broad range of behaviors. There is a need to study each behavior individually to better understand the role of each in the development of autistic children. Moreover, there are currently no longitudinal studies investigating change in these behaviors over development. METHODS: The goal of the present study was to explore the association between age and non-verbal IQ (NVIQ) on 15 RRB symptoms included in the Autism Diagnostic Interview-Revised (ADI-R) over time. A total of 205 children with ASD were assessed using the ADI-R at time of diagnosis, at age 6 years, and at age 11 years, and with the Wechsler Intelligence Scales for Children-Fourth Edition (WISC-IV) at age 8 years. RESULTS: The proportion of children showing each RRB tended to diminish with increasing age, except for sensitivity to noise and circumscribed interests, where the proportion increased over time. Although there was no significant main effect of NVIQ, there was a significant interaction between age and NVIQ. This was mainly driven by Difficulties with change in routine, for which higher NVIQ was associated with the behavior remaining relatively stable with age, while lower NVIQ was associated with the behavior becoming more prevalent with age. LIMITATIONS: The study focused on the presence/absence of each RRB but did not account for potential changes in frequency or severity of the behaviors over development. Furthermore, some limitations are inherent to the measures used. The ADI-R relies on parent report and hence has some level of subjectivity, while the Wechsler intelligence scales can underestimate the intellectual abilities of some autistic children. CONCLUSIONS: These results confirm that specific RRB are differentially linked to age and NVIQ. Studying RRB individually is a promising approach to better understanding how RRB change over the development of autistic children and are linked to other developmental domains.

Examining Trajectories of Daily Living Skills over the Preschool Years for Children with Autism Spectrum Disorder.

Preschool children with autism spectrum disorder (ASD) experience slower development of daily living skills (DLS) that are essential for independent functioning compared to typically developing children. Few studies have examined the trajectories of DLS in preschoolers with ASD and the existing literature has reported conflicting results. This study examined DLS trajectories and potential covariates for preschoolers with ASD from a multi-site longitudinal study following children from diagnosis to the end of grade 1. Multi-level modeling was conducted with DLS domain scores from the Vineland Adaptive Behavior Scales-2. The results demonstrated a positive trajectory of increasing scores over time, associations of age of diagnosis, developmental level, stereotypy, and language skills with the mean score at T4 or age 6 years, whereas rate of change was only associated with ASD symptom severity, such that an improvement in DLS trajectory was associated with lower and improving ASD symptom severity.

Generation of a pulsed low-energy electron beam using the channel spark device.

For the generation of low-energy electron beam, the design and characteristics of channel spark discharge (CSD) operating at a low voltage are presented in this paper. The discharge voltage, discharge current, X-ray emissions, and electron beam current were experimentally determined. The effects of the applied voltage, working gas pressure, and external capacitance on the CSD and beam parameters were measured. At an applied voltage of 11 kV, an oxygen gas pressure of 25 mTorr, and an external capacitance of 16.45 nF, the maximum measured current was 900 A. The discharge current increased with the increase in the pressure and capacitance, while its periodic time decreased with the increase in the pressure. Two types of the discharge were identified and recorded: the hollow cathode discharge and the conduction discharge. A Faraday cup was used to measure the beam current. The maximum measured beam current was 120 A, and the beam signal exhibited two peaks. The increase in both the external capacitance and the applied discharge voltage increased the maximum electron beam current. The electron-beam pulse time decreased with the increase in the gas pressure at a constant voltage and increased with the decrease in the applied discharge voltage. At an applied voltage of 11 kV and an oxygen gas pressure of 15 mTorr, the maximum beam energy was 2.8 keV. The X-ray signal intensity decreased with the increase in the gas pressure and increased with the increase in the capacitance.

Language impairment and early social competence in preschoolers with autism spectrum disorders: a comparison of DSM-5 profiles.

Children with autism spectrum disorder (ASD) and structural language impairment (LI) may be at risk of more adverse social-developmental outcomes. We examined trajectories of early social competence (using the Vineland-II) in 330 children aged 2-4 years recently diagnosed with ASD, and compared 3 subgroups classified by: language impairment (ASD/LI); intellectual disability (ASD/ID) and ASD without LI or ID (ASD/alone). Children with ASD/LI were significantly more socially impaired at baseline than the ASD/alone subgroup, and less impaired than those with ASD/ID. Growth in social competence was significantly slower for the ASD/ID group. Many preschool-aged children with ASD/LI at time of diagnosis resembled "late talkers" who appeared to catch up linguistically. Children with ASD/ID were more severely impaired and continued to lag further behind.

The role of prosody in discourse processing.

The influence of prosody and its visual analog, punctuation, in text comprehension was investigated in two experiments. In the first experiment 20 subjects listened to three taped passages of equal length and difficulty varying in intonation (normal, monotonous, or altered) and were tested on tasks of text comprehension and word recognition. In the second experiment 20 new subjects read the same passages but with varying punctuation (appropriate, no punctuation, or altered) and were also tested on text comprehension and word recognition. Subjects' reading time was also recorded. ANOVA results revealed that altered prosody and punctuation affect performance in a similar fashion and seriously impair text comprehension and word recognition. This sensitivity to altered intonation suggests that linguistic prosody not only supplies redundant cues for judging sentence structure but that it also manages attentional resources to help with semantic encoding of lexical units and with the organization of linguistic information in long term memory.