Autism spectrum disorder and autistic traits in the Avon Longitudinal Study of Parents and Children: precursors and early signs

Sensory-movement underpinnings of lifelong neurodivergence: getting a grip on autism

While the autism diagnosis emphasizes "deficits" in social communication, the article advances that sensory-movement differences underpin autism through a review of the following sources of evidence. This account critically challenges "autistic regression", with evidence that sensory-movement features appear by birth as the earliest signs of autism and underlie the behavioral differences used for diagnosis, which may reflect adaptations to inherent differences and misunderstandings from others. Sensory and motor differences are salient to autistic people, but they often go underrecognized by others. They cause cascading effects in infancy on behavior and communication through differences in sensorimotor learning, automatic imitation, eye contact, sensory perception, and interests. The article then explains how sensory processing differences may influence reduced perceptual narrowing, which involves a bottom-up information processing style grounded in the surrounding environment. Furthermore, this bottom-up processing may grow from reduced sensory integration in feedback loops potentially involving the cerebellum of the brain. The article then moves into implications for the widespread consequences of these inherent differences on quality of life. The article closes with implications for autism as a construct (including underestimated empathy and pain), testing the theory, providing sensory-sensitive support and acceptance of autistic people, and applications to diverse autistic people. The theory may apply particularly well to autistic women and girls, autistic people with speech divergence, autistic people with ADHD, and autistic people with co-occurring sensory and motor-related neurodivergences. Throughout the article, the theory also provides clinical, neurological, and experiential evidence for sensory and motor differences as lifelong, challenging the notion of "losing" (an) autism (diagnosis) as instead reflecting (risky and not necessarily "successful") camouflaging.

Associations of Autistic Traits and Autism with Incontinence and Constipation in a UK Birth Cohort

There is evidence that children with autism/autistic traits have higher risks of incontinence and constipation, but no studies have examined this in a large community-based cohort. Aim/Research question: are autistic traits and diagnosed autism prospectively associated with increased odds of incontinence and constipation in children and adolescents? This was a population-based cohort study based on data from the Avon Longitudinal Study of Parents and Children (n = 4233-4490 at age 9 years; n = 3403-3697 at age 14). We used multivariable logistic regression to examine associations of parent-reported autistic traits (sociability, repetitive behaviours, social-communication, coherence) (at ages 3-9 years) and autism with incontinence (bedwetting, daytime-wetting, soiling) and constipation (parent-reported at age 9, self-reported at age 14). We adjusted for parity, maternal age at delivery, child's sex and developmental level, maternal depression, and anxiety (antenatal and postnatal), and indicators of family socioeconomic status. Social-communication and speech coherence difficulties showed the strongest associations with incontinence, e.g., adjusted odds ratio (OR) and 95% confidence interval (CI) for the association between social-communication difficulties and daytime-wetting was 2.21 (1.47-3.32) and for coherence was 2.34 (1.60-3.43). The odds of soiling were also higher in children with social-communication (OR: 1.88, 95% CI 1.28-2.75) and coherence difficulties (OR: 2.04, 95% CI 1.43-2.93). Diagnosed autism was only associated with an increase in the odds of daytime-wetting (OR: 3.18, 95% CI 1.44-7.02). At 14 years, there was less evidence of associations between autistic traits and incontinence but there was evidence of associations between autistic traits and constipation: social-communication (OR: 1.68, 95% CI 1.13-2.49), coherence difficulties (OR: 1.64, 95% CI 1.11-2.41). Early assessment and treatment of incontinence/constipation should be considered for children with autistic traits.

Impaired brainstem auditory evoked potentials after in utero exposure to high dose paracetamol exposure

Paracetamol is an analgesic and antipyretic medication regarded as the safest over-the-counter pain and fever relief option during pregnancy. Paracetamol and its metabolites are known to reach the developing fetus through direct placental transfer and can cross the blood brain barrier. Several recent, large-scale epidemiologic studies suggest that in utero paracetamol exposure can increase the risk of neurodevelopmental conditions, including autism spectrum disorder (ASD), attention deficit hyperactivity disorder (ADHD) and developmental delay (DD). Since auditory processing deficits are a common feature of ASD, we hypothesized that animals exposed to paracetamol in utero will have impaired auditory brainstem function. We investigated this hypothesis by recording and analyzing click-evoked auditory brainstem responses (ABR) at postnatal day 21 and 29 in Sprague-Dawley rats. In utero exposure to high dose paracetamol exposure had no impact on body or brain weight. However, high dose paracetamol exposure did significantly delay ear opening and resulted in elevated ABR thresholds, and longer wave and interwave latencies. These changes in wave latency extended to the highest click intensity tested but were most severe near threshold. This data suggests that development and function of the auditory brainstem may be impacted by high dose paracetamol exposure and that simple, non-invasive tests of auditory function have utility as an early screening tool for neurodevelopmental disorders.

Obliteration of a glycinergic projection to the medial geniculate in an animal model of autism

Auditory dysfunction affects the vast majority of people with autism spectrum disorder (ASD) and can range from deafness to hypersensitivity. In utero exposure to the antiepileptic valproic acid (VPA) is associated with significant risk of an ASD diagnosis in humans and timed in utero exposure to VPA is utilized as an animal model of ASD. VPA-exposed rats have significantly fewer neurons in their auditory brainstem, thalamus and cortex, reduced ascending projections to the midbrain and thalamus and reduced descending projections from the cortex to the auditory midbrain. Consistent with these anatomical changes, VPA-exposed animals also have abnormal auditory brainstem responses. We have recently described a significant ascending projection from calbindin-positive neurons in the medial nucleus of the trapezoid body (MNTB) to the ventral division of the medial geniculate (vMG) in rats that bypasses the central nucleus of the inferior colliculus (CNIC). Since we found that axonal projections to the vMG in VPA-exposed rats are reduced beyond what is predicted from neuron loss alone, we hypothesize that VPA exposure would result in a significant reduction in the MNTB projection to the vMG. We examined this hypothesis by quantifying the proportion of retrogradely-labeled neurons in the MNTB of control and VPA-exposed animals after injections of retrograde tracers in the CNIC and vMG in control and VPA-exposed animals. Our results indicate that in control animals, the MNTB forms the largest projection from the superior olivary complex to the MG and that this projection is nearly abolished by in utero VPA exposure.

Feeding-Related Early Signs of Autism Spectrum Disorder: A Narrative Review

Feeding difficulties are prevalent among individuals with autism spectrum disorder (ASD). Nevertheless, the knowledge about the association between feeding-related early signs and child development remains limited. This review aimed to describe the signs and symptoms related to feeding during child development and to explore their relevance to the diagnosis of ASD. Specialists in nutrition and/or ASD conducted a search of MEDLINE, PsycINFO, and Web of Science databases. Although studies in typically developing children demonstrate age-related variations in hunger and satiety cues, the literature about early feeding indicators in ASD is scarce. Challenges such as shortened breastfeeding duration, difficulties in introducing solid foods, and atypical mealtime behaviors are frequently observed in children with ASD. The eating difficulties experienced during childhood raise concerns for caregivers who base their feeding practices on their perceptions of food acceptance or refusal. Considering the observed associations between feeding difficulties and ASD, the importance of recognizing feeding-related signs according to developmental milestones is emphasized to alert medical professionals that deviation in the formation of feeding habits and skills could indicate the need for ASD diagnostic investigation.

Home participation and personal and environmental factors in children and adolescents with Down syndrome

AIM

To describe current home participation (frequency, involvement) and caregiver's desire for change in home participation of children and adolescents with Down syndrome, as well as home environmental factors, and to explore the associations of personal and environmental factors with current participation and caregiver's desire for change.

METHOD

Eighty-two caregivers (mean age = 45 years 10 months) of children and adolescents with Down syndrome (mean age = 10 years 7 months) were surveyed about the child's home participation and environmental factors using the Participation and Environment Measure-Children and Youth. Furthermore, children's personal and environmental factors were collected. Results are reported using descriptive analysis and correlations (Spearman's rank correlation coefficients and Mann-Whitney U test) to describe the relationship between current participation and caregiver's desire for change, with personal and environmental factors as ordinal and nominal variables respectively (p < 0.05).

RESULTS

Children's participation was highest with regard to personal care management and lowest with regard to school-related activities. Most caregivers desired change in homework and household chores. Greater frequency was associated with male sex, caregiver less rigorous social distancing due to the COVID-19 pandemic, and children receiving therapies. Greater involvement was associated with younger age in children and higher environmental support. Older age in children was associated with caregiver's greater desire for change.

INTERPRETATION

Personal and environmental factors correlated with participation in specific ways. Creative strategies to promote participation that consider caregiver's wishes should be undertaken.

Participação em casa e fatores pessoais e ambientais em crianças e adolescentes com síndrome de Down

Objetivo

Descrever a participação em casa atual (frequência, envolvimento) e o desejo do cuidador por mudança na participação em casa de crianças e adolescentes com síndrome de Down, bem como fatores ambientais da casa, e explorar as associações de fatores pessoais e ambientais com a participação atual e o desejo do cuidador por mudança.

Método

Oitenta e dois cuidadores (média de idade = 45 anos e 10 meses) de crianças e adolescentes com síndrome de Down (média de idade = 10 anos e 7 meses) foram entrevistados sobre a participação em casa da criança e fatores ambientais utilizando a Medida de Participação e do Ambiente ‐ Crianças e Jovens. Além disso, foram coletados fatores pessoais e ambientais das crianças. Os resultados são relatados por meio de análise descritiva e correlações (coeficientes de correlação de Spearman ou teste U de Mann–Whitney) para descrever a relação entre a participação atual e o desejo do cuidador por mudança, com fatores pessoais e ambientais, para as variáveis ordinais e nominais, respectivamente (p < 0,05).

Resultados

A participação das crianças foi maior em cuidados pessoais e menor em atividades relacionadas à escola. A maioria dos cuidadores desejava mudança nas lições de casa e nas tarefas domésticas. Maior frequência de participação foi associada ao sexo masculino, distanciamento social menos rigoroso do cuidador devido à pandemia de covid‐19 e crianças recebendo terapia. O maior envolvimento na participação foi associado a uma idade mais jovem nas crianças e a um maior apoio do ambiente. A idade mais avançada das crianças foi associada ao maior desejo por mudança do cuidador.

Interpretação

Fatores pessoais e ambientais são correlacionados com a participação de formas específicas. Devem ser realizadas estratégias criativas para promover a participação e que considerem os desejos do cuidador.

Cortical dysmorphology and reduced cortico-collicular projections in an animal model of autism spectrum disorder

Autism spectrum disorder is a neurodevelopmental disability that includes sensory disturbances. Hearing is frequently affected and ranges from deafness to hypersensitivity. In utero exposure to the antiepileptic valproic acid is associated with increased risk of autism spectrum disorder in humans and timed valproic acid exposure is a biologically relevant and validated animal model of autism spectrum disorder. Valproic acid-exposed rats have fewer neurons in their auditory brainstem and thalamus, fewer calbindin-positive neurons, reduced ascending projections to the midbrain and thalamus, elevated thresholds, and delayed auditory brainstem responses. Additionally, in the auditory cortex, valproic acid exposure results in abnormal responses, decreased phase-locking, elevated thresholds, and abnormal tonotopic maps. We therefore hypothesized that in utero, valproic acid exposure would result in fewer neurons in auditory cortex, neuronal dysmorphology, fewer calbindin-positive neurons, and reduced connectivity. We approached this hypothesis using morphometric analyses, immunohistochemistry, and retrograde tract tracing. We found thinner cortical layers but no changes in the density of neurons, smaller pyramidal and non-pyramidal neurons in several regions, fewer neurons immunoreactive for calbindin-positive, and fewer cortical neurons projecting to the inferior colliculus. These results support the widespread impact of the auditory system in autism spectrum disorder and valproic acid-exposed animals and emphasize the utility of simple, noninvasive auditory screening for autism spectrum disorder.

Handedness in autism spectrum disorders and intellectually disabled children and adolescents - Contrasting caregivers' reports with assessments of hand preference

Background

A higher rate of atypical handedness prevalence (non-right-handedness or left-, mixed-hand dominance) has been recurrently reported in individuals diagnosed with autism spectrum disorder (ASD) compared to individuals with other types of developmental disabilities. However, the exact magnitude of this difference as well as the presence of possible contributing factors remained unknown. The main aim of this study was to understand caregivers' impression of the handedness of their child with developmental disabilities and its relationship with assessments of the child using a hand preference scale.

Methods and procedures

The sample of the present study was 1116 individuals with developmental disabilities from two countries, 541 (51.5%) individuals from Iran and 575 (48.5%) individuals from the Kurdistan Region of Iraq (KRI). The handedness of the sample was evaluated based on the parental report and utilizing a standardized scale (The Hand-Preference Demonstration Test "HPDT").

Outcomes and results

There was a statistically significant difference between caregivers' reports on their dependents' handedness and the application of a valid hand preference scale and they do not necessarily overlap. There was a statistically significant relationship between handedness and type of developmental disabilities based on caregivers' reports and individuals with ASD were more non-right-handed compared to individuals with ID based on the caregivers' report. Hence similar difference was not seen between the ASD and ID groups when HDTP was applied as a diagnostic scale. While left-handedness in the ASD and ID group was similar (23-24%), mixed-handedness in the ASD group was 38% compared to 33% in the ID group.

Conclusions and implications

The Hand-Preference Demonstration Test (HPDT) was a valid way to determine the hand preference of individuals with ASD and ID. It is concluded that parental reports on their offspring with ASD's hand preference need to be approved through the application of a scale and caregivers and professionals need to be more aware of early motor symptoms such as handedness. Further research should focus on the role of handedness in the development of fine motor skills and eye-hand coordination in children with differing developmental disabilities and variations among those differing impairments.

Using the Griffiths Mental Development Scales to Evaluate a Developmental Profile of Children with Autism Spectrum Disorder and Their Symptomatologic Severity

Early diagnosis is crucial for Autism spectrum disorder (ASD) and is achieved through a screening of developmental indicators to recognise children who are at risk of autism. One of the most widely used instruments in clinical practice for assessing child development is the Griffiths Mental Development Scale (GMDS). We sought (a) to assess longitudinally whether children diagnosed with ASD, with a mean age of 33.50 months (SD 7.69 months), show a developmental delay of abilities measured by the GMDS over time and (b) to analyse which skills of the GMDS could be associate to the symptomatologic severity of ASD. Our results showed lower scores of General Quotient and all sub-quotients of GMDS from first (T0) to second assessment (T1), except for the Performance sub-quotient. Three sub-quotients (Personal-Social, Hearing and Language and Practical Reasoning) also associate symptom severity at the time when the diagnosis of ASD is made.

Relationship between Parental Concerns about Social-Emotional Reciprocity Deficits and Their Children's Final ASD Diagnosis

Concerns raised by parents regarding their child's development are compatible with the child's final diagnosis of autism spectrum disorder. A better understanding of the relationship between parental concerns and a final diagnosis of autism spectrum disorder is therefore critical. In the current study, we compared the frequencies of parental concerns related to DSM-5 criteria for autism spectrum disorder between pair-matched groups with and without a final diagnosis of autism spectrum disorder and determined which parental concerns predicted a final diagnosis of autism spectrum disorder. The cohort included 80 participants (48-154 months of age, IQ > 70) assessed for a possible autism spectrum disorder diagnosis. Parental concerns were retrieved from the free-description portion of the introductory questions of the Autism Diagnostic Interview-Revised and analyzed to assess whether they corresponded to any of the seven DSM-5 criteria for ASD. The two groups only differed in the frequency of parental concerns relating to deficits in social-emotional reciprocity. Parents of children diagnosed with autism spectrum disorder were four times as likely to report deficits in social-emotional reciprocity. This finding highlights the significance of parental concerns regarding deficits in social-emotional reciprocity in predicting a final diagnosis of autism spectrum disorder.

Altered Developmental Trajectory in Male and Female Rats in a Prenatal Valproic Acid Exposure Model of Autism Spectrum Disorder

Early motor and sensory developmental delays precede Autism Spectrum Disorder (ASD) diagnosis and may serve as early indicators of ASD. The literature on sensorimotor development in animal models is sparse, male centered, and has mixed findings. We characterized early development in a prenatal valproic acid (VPA) model of ASD and found sex-specific developmental delays in VPA rats. We created a developmental composite score combining 15 test readouts, yielding a reliable gestalt measure spanning physical, sensory, and motor development, that effectively discriminated between VPA and control groups. Considering the heterogeneity in ASD phenotype, the developmental composite offers a robust metric that can enable comparison across different animal models of ASD and can serve as an outcome measure for early intervention studies.

Sleep quality and temperament in association with autism spectrum disorder among infants in Japan

BACKGROUND

Sleep problems and irritable temperaments are common among infants with autism spectrum disorder (ASD). The prospective association between such sleep problems and irritable temperaments and ASDs needs to be determined for elucidating the mechanism and exploring the future intervention study. Thus, in this study, we investigated whether sleep quality and temperament in 1-month-old infants are associated with the onset of ASD in 3-year-old children. We also assessed its sex-stratified associations.

METHODS

We conducted a longitudinal study using data from 69,751 mothers and infants from a large-cohort study, the Japan Environment and Children's Study. We examined the prospective association between infant sleep quality and temperament at 1 month of age and ASD diagnosis by 3 years of age.

RESULTS

Here we show infants with longer daytime sleep have a higher risk of later ASD than those with shorter daytime sleep (risk ratio [RR]: 1.33, 95% confidence interval [CI]: 1.01-1.75). Infants who experienced intense crying have a higher risk of ASD than those who did not (RR: 1.31, 95% CI: 1.00-1.72). There is a difference in sex in the association between a bad mood and later ASD. In particular, female infants experiencing bad moods have a higher risk of ASD than others (RR: 3.59, 95% CI: 1.91-6.75).

CONCLUSIONS

The study findings provide important information for future intervention to reduce the risk of future ASD.

Abnormal auditory brainstem responses in an animal model of autism spectrum disorder

Auditory dysfunction is a common feature of autism spectrum disorder (ASD) and ranges from deafness to hypersensitivity. The auditory brainstem response (ABR) permits study of the amplitude and latency of synchronized electrical activity along the ascending auditory pathway in response to clicks and pure tone stimuli. Indeed, numerous studies have shown that subjects with ASD have ABR abnormalities. In utero exposure to the antiepileptic drug valproic acid (VPA) is associated with human cases of ASD and is used as an animal model of ASD. Previous studies have shown that VPA-exposed animals have significantly fewer neurons in the auditory brainstem and thalamus, reduced ascending projections to the auditory midbrain and thalamus and increased neuronal activation in response to pure tone stimuli. Accordingly, we hypothesized that VPA-exposed animals would have abnormal ABRs throughout their lifespans. We approached this hypothesis in two cohorts. First, we examined ABRs from both ears on postnatal day 22 (P22). Then, we examined monaural ABRs in animals at P28, 60, 120, 180, 240, 300 and 360. Our results suggest that at P22, VPA-exposed animals have elevated thresholds and increased peak latencies. However, by P60 these differences largely normalize with differences appearing only near hearing threshold. Additionally, our analysis revealed that maturation of ABR waves occurred at different trajectories in control and VPA-exposed animals. These results, together with our previous work, suggest that VPA exposure not only impacts total neuron number and connectivity, but also auditory evoked responses. Finally, our longitudinal analysis suggests that delayed maturation of auditory brainstem circuits may impact ABRs throughout the lifespan of the animal.

Interrelated development of autism spectrum disorder symptoms and eating problems in childhood: a population-based cohort

Eating problems, such as food selectivity or picky eating, are thought to be an epiphenomenon of autism spectrum disorders (ASD). Yet eating problems are also common in the general pediatric population and overlap with ASD symptoms. However, the temporal association between ASD symptoms and eating problems is poorly understood. This study examines the bidirectional association between ASD symptoms and eating problems across child development, and investigates whether these associations differ by child sex. Participants (N = 4,930) were from the population-based Generation R Study. Parents reported their child's ASD symptoms and eating problems using the Child Behavior Checklist at 5 assessments from toddlerhood to adolescence (1.5 to 14 years, 50% girls). A Random Intercept Cross-Lagged Panel Model was used to examine the lagged associations between ASD symptoms and eating problems at the within-person level, controlling for stable, trait-like differences at the between-person level. At the between-person level, there was a strong correlation between ASD symptoms and eating problems (β = .48, 95% CI: 0.38 to 0.57). Controlling for these between-person effects, there was limited evidence for consistent, predictive effects of ASD symptoms and eating problems at the within-person level. Associations did not differ by child sex. Findings suggest that ASD symptoms and eating problems may represent a cluster of traits that are highly stable from early childhood to adolescence, which have a minimal reciprocal effect at the individual-level. Future research could focus on these trait-like qualities to inform the development of supportive, family-focused interventions.

Food Difficulties in Infancy and ASD: A Literature Review

PURPOSE

The aim of this literature review is to investigate the potential association between specific food difficulties and autism spectrum disorder (ASD) during the first two years of life.

MATERIALS

The search was conducted in PubMed, Google Scholar, Embase and PsycInfo databases.

RESULTS

Twenty-one studies were synthesized (3763 infants and children). Difficulties during breastfeeding, breast milk refusal and avoidance of taking solids have been linked to ASD. Infants with ASD have been referred to as picky eaters. Problematic mealtime behaviour during infancy has also been associated with ASD.

CONCLUSIONS

The present review highlights the association between food difficulties, including problematic mealtime behaviours, food selectivity, breastfeeding difficulties and food refusal during infancy and ASD early during life, including the first months.

Comparison of classification algorithms for predicting autistic spectrum disorder using WEKA modeler

BACKGROUND

In healthcare area, big data, if integrated with machine learning, enables health practitioners to predict the result of a disorder or disease more accurately. In Autistic Spectrum Disorder (ASD), it is important to screen the patients to enable them to undergo proper treatments as early as possible. However, difficulties may arise in predicting ASD occurrences accurately, mainly caused by human errors. Data mining, if embedded into health screening practice, can help to overcome the difficulties. This study attempts to evaluate the performance of six best classifiers, taken from existing works, at analysing ASD screening training dataset.

RESULT

We tested Naive Bayes, Logistic Regression, KNN, J48, Random Forest, SVM, and Deep Neural Network algorithms to ASD screening dataset and compared the classifiers' based on significant parameters; sensitivity, specificity, accuracy, receiver operating characteristic, area under the curve, and runtime, in predicting ASD occurrences. We also found that most of previous studies focused on classifying health-related dataset while ignoring the missing values which may contribute to significant impacts to the classification result which in turn may impact the life of the patients. Thus, we addressed the missing values by implementing imputation method where they are replaced with the mean of the available records found in the dataset.

CONCLUSION

We found that J48 produced promising results as compared to other classifiers when tested in both circumstances, with and without missing values. Our findings also suggested that SVM does not necessarily perform well for small and simple datasets. The outcome is hoped to assist health practitioners in making accurate diagnosis of ASD occurrences in patients.

Early manifestations of genetic liability for ADHD, autism and schizophrenia at ages 18 and 24 months

Background

ADHD and autism are neurodevelopmental conditions, for which non-specific precursors or early signs include difficulties with language and motor skills, and differences in temperament in the first and second year of life. These early features have also been linked to later diagnosis of schizophrenia which is widely considered to have neurodevelopmental origins. Given that ADHD, autism and schizophrenia are all highly heritable, we tested the hypothesis that in the general population, measures of toddler language development, motor development and temperament are associated with genetic liability to ADHD, autism and/or schizophrenia.

Methods

Data were analysed from the Avon Longitudinal Study of Parents and Children (ALSPAC) which included motor development scores at age 18 months and language development and temperament scores at age 24 months (N=7498). Genetic liability was indexed by polygenic risk scores (PGS) for ADHD, autism and schizophrenia.

Results

ADHD PGS were associated with specific temperament scales (higher activity β=0.07, 95% CI=0.04, 0.09 and lower withdrawal β=-0.05, 95% CI=-0.07, -0.02) as well as better gross motor scores (β=0.04, 95% CI=0.01, 0.06). Schizophrenia PGS were associated with one specific temperament scale (negative mood β=0.04, 95% CI=0.02, 0.07). We did not find strong evidence of association of autism PGS with any of the toddler measures; there was also not strong evidence of association with motor or language delays for any of the PGS.

Conclusions

This study suggests that some specific aspects of early temperament and gross motor differences in the general population could represent part of the early manifestation of genetic liability to neurodevelopmental conditions.

Identifying neuroanatomical and behavioral features for autism spectrum disorder diagnosis in children using machine learning

Autism spectrum disorder (ASD) is a neurodevelopmental disorder that can cause significant social, communication, and behavioral challenges. Diagnosis of ASD is complicated and there is an urgent need to identify ASD-associated biomarkers and features to help automate diagnostics and develop predictive ASD models. The present study adopts a novel evolutionary algorithm, the conjunctive clause evolutionary algorithm (CCEA), to select features most significant for distinguishing individuals with and without ASD, and is able to accommodate datasets having a small number of samples with a large number of feature measurements. The dataset is unique and comprises both behavioral and neuroimaging measurements from a total of 28 children from 7 to 14 years old. Potential biomarker candidates identified include brain volume, area, cortical thickness, and mean curvature in specific regions around the cingulate cortex, frontal cortex, and temporal-parietal junction, as well as behavioral features associated with theory of mind. A separate machine learning classifier (i.e., k-nearest neighbors algorithm) was used to validate the CCEA feature selection and for ASD prediction. Study findings demonstrate how machine learning tools might help move the needle on improving diagnostic and predictive models of ASD.

Patterns of objectively measured motor activity among infants developing ASD and concerns for ADHD

BACKGROUND

Heightened motor activity is a hallmark of attention-deficit/hyperactivity disorder (ADHD), yet high activity levels are also often reported in young children with autism spectrum disorder (ASD). It is currently unclear whether increased motor activity represents a distinct versus shared early predictor of ASD and ADHD; no prior studies have directly examined this prospectively. We investigated differences in longitudinal patterns of objectively measured motor activity during early development.

METHODS

Participants included 113 infants at high and low risk for ASD or ADHD. Continuous motion-based activity was recorded using tri-axial accelerometers at 12, 18, 24, and 36 months of age. At 36 months, participants were categorized into one of three outcome groups: ASD (n = 19), ADHD Concerns (n = 17), and Typically Developing (TD; n = 77). Group differences in trajectories of motor activity were examined in structured and semistructured contexts. Associations with behaviors relevant to ASD, ADHD, and general development were also examined.

RESULTS

In both structured and semistructured contexts, both the ASD and ADHD Concerns groups exhibited heightened activity relative to the TD group by 18 months; the ASD group exhibited higher activity than the ADHD Concerns group at 24-36 months in the structured context only. Attention/behavior regulation, nonverbal, and verbal development-but not social engagement-were differentially associated with objectively measured activity by outcome group across contexts.

CONCLUSIONS

Overactivity may be a shared, rather than distinct, precursor of atypical development in infants/toddlers developing ASD and concerns for ADHD, emerging as early as 18 months. Group differences in overactivity may be context-specific and associated with different underlying mechanisms.

Time to Diagnosis of Autism Spectrum Disorders in Children with Coexisting Developmental Behavioral Disorders

OBJECTIVE

Our study evaluates whether having an alternate developmental behavioral disorder (DBDs) diagnosis before diagnosis of autism spectrum disorders (ASD) is associated with delays in diagnosis in a nationally representative sample.

METHODS

Data were obtained from the 2011 National Survey of Pathways to Diagnosis and Services, a survey of children aged 6 to 17 years with ASD, developmental delay, or intellectual disability. A total of 1049 children met inclusion criteria for this study. Of these, 799 children were identified as "late" diagnosis if >12 months elapsed between the age parents reported concerns to a provider and age of ASD diagnosis and 250 as "timely" diagnosis if the gap was ≤12 months. Univariate and multivariate logistic regressions were used to look for association between having an alternate DBDs diagnosed before ASD and "timely" versus "late" ASD diagnosis.

RESULTS

The mean time elapsed between the age parents reported concerns to a provider and age of ASD diagnosis was 51 months for children with an alternate DBDs diagnosis before receiving ASD diagnosis and 29 months for those diagnosed with alternate DBDs concurrently with ASD. Having alternate DBDs diagnosis before diagnosis with ASD was associated with "late" ASD diagnosis as follows: developmental delay (adjusted odds ratio [aOR,] 3.46; 95% confidence interval [CI], 1.86-6.42; p < 0.001), intellectual disability (aOR, 9.75; 95% CI, 3.0-31.60; p = 0.04), attention-deficit disorder (aOR, 11.07; 95% CI, 3.43-35.71; p < 0.001), depression (aOR, 8.05; 95% CI, 1.07-60.03; p = 0.0495), and behavioral conduct disorder (aOR, 9.9; 95% CI, 3.55-27.62; p < 0.001).

CONCLUSION

These findings highlight the importance of research to improve the early diagnosis of ASD even in the presence of coexisting developmental behavioral disorders.

Early Motor Signs in Autism Spectrum Disorder

A growing number of literature data suggest the presence of early impairments in the motor development of children with autism spectrum disorder, which could be often recognized even before the appearance of the classical social communication deficits of autism. In this narrative review, we aimed at performing an update about the available data on the early motor function in children with autism spectrum disorder. Early motor impairment in these children can manifest itself both as a mere delay of motor development and as the presence of atypicalities of motor function, such as a higher rate and a larger inventory, of stereotyped movements both with and without objects. In the perspective of a timely diagnosis, the presence of early motor signs can be an important clue, especially in an individual considered at high risk for autism. Motor and communication (both verbal and non-verbal) skills are connected and a pathogenetic role of early motor dysfunctions in the development of autism can be hypothesized. From this, derives the importance of an early enabling intervention aimed at improving motor skills, which could also have favorable effects on other aspects of development.

The Role of the Maternal and Child Health Handbook in Developmental Surveillance: The Exploration of Milestone Attainment Trajectories

Despite the pivotal role of developmental surveillance in pediatric practice for the early detection of neurodevelopmental disorders (NDDs), there are several barriers, including scarcity of time and staff availability, to its implementation. Additionally, inadequate parental knowledge on what to expect about their child's development contributes to potential delays in the early identification of NDDs. Home-based records (HBRs) are widely used in both high-income and low- and middle-income countries, allowing caregivers to prospectively chart the child's development, including milestone attainment, and thus can be a useful tool for developmental surveillance. Therefore, we analyzed data on milestone attainment from birth to 5 years of age obtained through the home-based records (the Maternal Child Health Handbook: MCHH) in 720 children who attended the Hirosaki Five-year-old children Developmental Health Check-up Study in Hirosaki, Japan to identify trajectory patterns of milestone attainment. Parallel process latent class growth analysis on four milestone domains (motor, social interaction, communication, and self-care) revealed three different trajectories (Class 1: "Consistent milestone attainment" group; 42%, Class 2: "subtle initial delay and catch-up" group; 45%, Class 3: "Consistent failure to attain expected milestones" group; 13%). In Class 3, 90% of children were diagnosed with at least one NDDs at age 5 and approximately 65% of children had autism spectrum disorder and/or intellectual disability, the rate of which was higher than that in the other two classes. Boys and preterm-born children were more likely to be assigned to classes with less favorable trajectories of milestone attainment. Although the use of the MCHH alone does not substitute diagnostic evaluation for NDDs, our study findings suggest the potential utility of the MCHH as a tool to educate parents on what longitudinal patterns of milestone attainment are concerning and require prompt visits to professionals.

Child Autistic Traits, Food Selectivity, and Diet Quality: A Population-Based Study

BACKGROUND

Children with Autism Spectrum Disorders (ASDs) tend to be selective in their food intake, which may compromise their diet quality. While ASD diagnoses capture severe levels of impairment, autistic traits vary on a continuum throughout the population. Yet, little is known about how autistic traits relate to diet quality at the population level.

OBJECTIVES

This study examines the association between autistic traits in early childhood and diet quality in mid-childhood and explores the mediating role of food selectivity.

METHODS

Participants were children (n = 4092) from the population-based Generation R Study. Parents reported their child's autistic traits at 1.5, 3, and 6 years; food selectivity at 4 years; and food intake at 8 years, from which a diet quality score was derived. Associations of autistic traits and the autistic trait trajectory (identified using Latent Class Growth Modelling) with diet quality were examined using multiple linear regression models. The indirect effect of food selectivity in the association between autistic traits at 1.5 years and diet quality was examined using mediation analysis.

RESULTS

Autistic traits were associated with diet quality (e.g., 1.5 years: β = -0.09; 95% CI: -0.13 to -0.06). Two classes captured the autistic trait trajectories from 1.5 to 6 years: children with "low and stable" (95%) and "high and increasing" (5%) mean scores. Children in the high and increasing group had poorer diet quality than those in the low and stable group (β = -0.28; 95% CI: -0.44 to -0.11). Food selectivity mediated the association between autistic traits at 1.5 years and diet quality at 8 years (βindirect = -0.03; 95% CI: -0.03 to -0.02).

CONCLUSIONS

Autistic traits in early childhood are associated with poorer diet quality in mid-childhood, and food selectivity appears to mediate this association. Interventions intended to optimize nutrition in children with elevated autistic traits may integrate behavioral strategies to support parents' responding to their child's food selectivity.

The Untouchable Ventral Nucleus of the Trapezoid Body: Preservation of a Nucleus in an Animal Model of Autism Spectrum Disorder

Autism spectrum disorder (ASD) is a neurodevelopmental condition characterized by repetitive behaviors, poor social skills, and difficulties with communication and hearing. The hearing deficits in ASD range from deafness to extreme sensitivity to routine environmental sounds. Previous research from our lab has shown drastic hypoplasia in the superior olivary complex (SOC) in both human cases of ASD and in an animal model of autism. However, in our study of the human SOC, we failed to find any changes in the total number of neurons in the ventral nucleus of the trapezoid body (VNTB) or any changes in cell body size or shape. Similarly, in animals prenatally exposed to the antiepileptic valproic acid (VPA), we failed to find any changes in the total number, size or shape of VNTB neurons. Based on these findings, we hypothesized that the neurotransmitter profiles, ascending and descending axonal projections of the VNTB are also preserved in these neurodevelopmental conditions. We investigated this hypothesis using a combination of immunohistochemistry and retrograde tract tracing. We found no difference between control and VPA-exposed animals in the number of VNTB neurons immunoreactive for choline acetyltransferase (ChAT). Additionally, we investigated the ascending projections from the VNTB to both the central nucleus of the inferior colliculus (CNIC) and medial geniculate (MG) and descending projections to the cochlea. Our results indicate no significant differences in the ascending and descending projections from the VNTB between control and VPA-exposed animals despite drastic changes in these projections from surrounding nuclei. These findings provide evidence that certain neuronal populations and circuits may be protected against the effects of neurodevelopmental disorders.

Reduced false positives in autism screening via digital biomarkers inferred from deep comorbidity patterns

Here, we develop digital biomarkers for autism spectrum disorder (ASD), computed from patterns of past medical encounters, identifying children at high risk with an area under the receiver operating characteristic exceeding 80% from shortly after 2 years of age for either sex, and across two independent patient databases. We leverage uncharted ASD comorbidities, with no requirement of additional blood work, or procedures, to estimate the autism comorbid risk score (ACoR), during the earliest years when interventions are the most effective. ACoR has superior predictive performance to common questionnaire-based screenings and can reduce their current socioeconomic, ethnic, and demographic biases. In addition, we can condition on current screening scores to either halve the state-of-the-art false-positive rate or boost sensitivity to over 60%, while maintaining specificity above 95%. Thus, ACoR can significantly reduce the median diagnostic age, reducing diagnostic delays and accelerating access to evidence-based interventions.

Central Auditory and Vestibular Dysfunction Are Key Features of Autism Spectrum Disorder

Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by repetitive behaviors, poor social skills, and difficulties with communication. Beyond these core signs and symptoms, the majority of subjects with ASD have some degree of auditory and vestibular dysfunction. Dysfunction in these sensory modalities is significant as normal cognitive development depends on an accurate representation of our environment. The hearing difficulties in ASD range from deafness to hypersensitivity and subjects with ASD have abnormal sound-evoked brainstem reflexes and brainstem auditory evoked potentials. Vestibular dysfunction in ASD includes postural instability, gait dysfunction, and impaired gaze. Untreated vestibular dysfunction in children can lead to delayed milestones such as sitting and walking and poor motor coordination later in life. Histopathological studies have revealed that subjects with ASD have significantly fewer neurons in the auditory hindbrain and surviving neurons are smaller and dysmorphic. These findings are consistent with auditory dysfunction. Further, the cerebellum was one of the first brain structures implicated in ASD and studies have revealed loss of Purkinje cells and the presence of ectopic neurons. Together, these studies suggest that normal auditory and vestibular function play major roles in the development of language and social abilities, and dysfunction in these systems may contribute to the core symptoms of ASD. Further, auditory and vestibular dysfunction in children may be overlooked or attributed to other neurodevelopmental disorders. Herein we review the literature on auditory and vestibular dysfunction in ASD. Based on these results we developed a brainstem model of central auditory and vestibular dysfunction in ASD and propose that simple, non-invasive but quantitative testing of hearing and vestibular function be added to newborn screening protocols.

Neonatal Imitation, Intersubjectivity, and Children With Atypical Development: Do Observations on Autism and Down Syndrome Change Our Understanding?

Almost all studies on neonatal imitation to date seem to have focused on typically developing children, and we thus lack information on the early imitative abilities of children who follow atypical developmental trajectories. From both practical and theoretical perspectives, these abilities might be relevant to study in children who develop a neuropsychiatric diagnosis later on or in infants who later show impaired ability to imitate. Theoretical in the sense that it will provide insight into the earliest signs of intersubjectivity—i.e., primary intersubjectivity—and how this knowledge might influence our understanding of children following atypical trajectories of development. Practical in the sense that it might lead to earlier detection of certain disabilities. In the present work, we screen the literature for empirical studies on neonatal imitation in children with an Autism spectrum disorder (ASD) or Down syndrome (DS) as well as present an observation of neonatal imitation in an infant that later was diagnosed with autism and a re-interpretation of previously published data on the phenomenon in a small group of infants with DS. Our findings suggest that the empirical observations to date are too few to draw any definite conclusions but that the existing data suggests that neonatal imitation can be observed both in children with ASD and in children with DS. Thus, neonatal imitation might not represent a useful predictor of a developmental deficit. Based on current theoretical perspectives advocating that neonatal imitation is a marker of primary intersubjectivity, we propose tentatively that an ability to engage in purposeful exchanges with another human being exists in these populations from birth.

The course and prognostic capability of motor difficulties in infants showing early signs of autism

Delays within the motor domain are often overlooked as an early surveillance marker for autism. The present study evaluated motor difficulties and its potential as an early predictive marker for later autism likelihood in a cohort of infants (N = 96) showing early behavioral signs of autism aged 9-14 months. The motor domain was evaluated using the motor subscales of the Mullen Scales of Early Learning at baseline, and at a 6-month follow-up. The Autism Diagnostic Observation Schedule - Toddler Module (ADOS-T) was completed at follow-up as a measure of autism likelihood. Motor difficulties were common at baseline, with 63/96 (65.6%) infants scoring very low or below average in the gross motor domain and 29/96 (30.2%) in the fine motor domain. At follow-up, gross motor difficulties had resolved for many, with 23/63 (36.5%) infants maintaining these difficulties. Fine motor difficulties resolved in fewer infants, with 20/29 (69.0%) continuing to present with fine motor delays at follow-up. Adjusted linear regression models suggested that fine motor scores at baseline (β = -0.12, SE = 0.04) and follow-up (β = -0.17, SE = 0.05) were associated with higher ADOS-T scores; with difficulties across both timepoints (β = 5.60, SE = 1.35) the strongest (largest in magnitude) association with ADOS-T scores of the predictors examined. Motor difficulties are prominent in children displaying emerging signs of autism, with persistent fine motor difficulties predictive of the developing autism phenotype. The findings indicate the potential clinical value of including evaluation of motor skills within early autism surveillance measures. LAY SUMMARY: This prospective study evaluated motor development over a 6-month period in infants showing early behavioral signs of autism. Atypical motor development was a common feature of infants showing early signs of autism and persistent fine motor difficulties were predictive of the emerging autism phenotype.

Understanding How Parents Make Meaning of Their Child's Behaviors During Screening for Autism Spectrum Disorders: A Longitudinal Qualitative Investigation

A family's journey in understanding their child's behaviors in relation to Autism Spectrum Disorders (ASD) frequently begins with screening. This study aimed to characterize the interpretive processes that unfold for parents. We employed longitudinal interviews with 19 families engaged in a community-based multi-stage screening protocol. Parents participated in 1-6 interviews dependent upon children's length of engagement in the screening protocol; data were analyzed through modified grounded theory. Parents who moved towards understanding their child's behaviors as ASD expressed (1) sensitization to ASD symptoms, (2) differentiation from other developmental conditions, and (3) use of the ASD diagnosis to explain the etiology of concerning behaviors. Identifying interpretive processes involved during ASD screening provides new opportunities for shared decision-making.

Temperament in individuals with Autism Spectrum Disorder: A systematic review

The study of temperament in Autism Spectrum Disorder (ASD) has the potential to provide insight regarding variability in the onset, nature, and course of both core and co-morbid symptoms. The aim of this systematic review was to integrate existing findings concerning temperament in the context of ASD. Searches of Medline, PsychInfo and Scopus databases identified 64 relevant studies. As a group, children and adolescents with ASD appear to be temperamentally different from both typically developing and other clinical non-ASD groups, characterized by higher negative affectivity, lower surgency, and lower effortful control at a higher-order level. Consistent with research on typically developing children, correlational findings and emerging longitudinal evidence suggests that lower effortful control and higher negative affect are associated with increased internalizing and externalizing problems in ASD samples. Longitudinal studies suggest there may be temperamental differences between high familial risk infants who do and do not develop ASD from as early as 6-months of age. Limitations of existing research are highlighted, and possible directions for future research to capitalize on the potential afforded through the study of temperament in relation to ASD are discussed.

The Route to Autism Spectrum Diagnosis in Pediatric Practice in Bulgaria

Diagnosis of autism spectrum disorder (ASD) before the age of three years is a challenge. Analyzing the present practice may help reaching that goal. Aim: To investigate developmental abnormalities and diagnostic pathway of ASD patients in pediatric practice. Methods: Retrospective cross-sectional study of 192 children aged 13 months to 17 years 11 months (average 4 years 9 months), investigated in an outpatient and hospital setting from January 2015 to June 2018 by a semi-structured history and clinical examination, and diagnosed with ASD by Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) criteria. Results: Behavioral peculiarities were detected in the history of the first two years of life in 74.8% of the subjects. The first developmental abnormalities were noticed by the parents at ages from 8 to 36 months (mean 15.6 months) and were predominantly in speech (in 94.6%) and non-verbal communication (11.3%). Developmental regression was reported in 42.1% of the patients occurring between the ages of 6 and 50 months (mean 17.9 months), affecting most commonly speech (88.4% of cases), non-verbal communication (29.2%), and behavior (12.8%). By history, the first manifestations of ASD were noticed at ages from 8 months to 84 months (mean 18.5 months), and were disorders of expressive speech (in 66.7% of cases), receptive speech (in 45.8%), non-verbal communication (35.4%), behavior (27.6%), play (8.9%), socialization (5.7%), and joint attention (2.1%). The most common motive for specialized consultation was delay in language development—in 84.6% of children. The age of ASD diagnosis varied between 12 and 132 months (mean 39.7 months), and the time period between first ASD manifestations and diagnosis was in the range of 0 to 79 months (mean 23.3 months). Many symptoms of abnormal social communication, unnoticed by parents, were detected objectively in more than 95% of the cases—absent or rare spontaneous or reciprocal smile; lack of sharing of interest or affect; abnormal eye contact; lack of finger pointing; lack of gaze to a pointed object; poor facial expressions; lack of imaginary play, etc. Conclusions: Almost two years are needed for diagnosing abnormal development in other domains besides speech in ASD patients. Diagnosis before the age of three years can be achieved by focusing parents’ and pediatricians’ attention on social communication and behavior in patients with speech delay or developmental regression.

Assessment of Autism Symptoms From 6 to 18 Months of Age Using the Autism Observation Scale for Infants in a Prospective High-Risk Cohort

The objectives were to characterize behavioral signs of autism spectrum disorder (ASD) in younger siblings of diagnosed children (high-risk; HR) and examine classification features of the Autism Observation Scale for Infants (AOSI). Participants (501 HR and 180 low-risk [LR]) were assessed between 6 and 18 months using the AOSI and at age 3 for ASD diagnoses. Total AOSI scores differentiated HR infants later diagnosed with ASD starting at 12 months. ROC analyses identified 12- and 18-month cutoff scores associated with 0.52 sensitivity and 0.74 specificity and 0.73 sensitivity and 0.65 specificity, respectively. Although classification accuracy does not support use as a standalone screen, the AOSI identifies features associated with ASD starting at 6 months and differentiates HR infants with ASD by 12 months.

Utilization of the Maternal and Child Health Handbook in Early Identification of Autism Spectrum Disorder and Other Neurodevelopmental Disorders

There is relatively little information about prospectively reported developmental milestones from caregivers of children who go on to be diagnosed with neurodevelopmental disorders (NDDs), including autism spectrum disorder (ASD). The current study examined rates of early skill attainment in 5-year-old children who participated in a comprehensive in-person assessment for NDDs in Hirosaki in Japan. Developmental milestone data were extracted from their Maternal and Child Health Handbook (MCHH), a booklet distributed to all pregnant women as part of universal health care. Seven hundred and twenty children underwent the assessment, among whom 455 received one or more NDD diagnoses (ASD: n = 124, non-ASD NDD: n = 331). Developmental skills were organized into four domains (motor, social interaction, communication, self-help), and the cumulative number of potential delays in each domain was calculated for each participant within three different age ranges (by 12 months, by 24 months, and by 36 months). Even by age 12 months, children with ASD/NDDs showed more potential delays across domains compared to those who received no NDD diagnosis. However, differences between those with ASD and those with non-ASD NDDs were not apparent until 24 months for social interaction and communication, and 36 months for self-help. These findings provide insights into specific behaviors that could be used to screen for ASD and other NDDs. In addition, the present study indicates the potential utility of the MCHH as a broadband screening tool to educate parents about what to look for in charting their child's early development. LAY SUMMARY: The present study examined prospectively charted developmental milestones from home-based records used as part of universal health care in 720 5-year-old children from Hirosaki, Japan. All children participated in a comprehensive evaluation to determine if they met criteria for a neurodevelopmental disorder (NDD), including autism spectrum disorder (ASD). Compared to those who received no NDD diagnosis, children with NDDs exhibited higher rates of potential delays across developmental domains, including social interaction, communication, and self-help. For some children, these delays were apparent before the age of 12 months. Differences between diagnostic groups became even more pronounced by 24 and 36 months, well before the average age of diagnosis. This suggests that home-based records can be useful tools to educate caregivers about what to look for in charting their child's early development and could assist with early screening efforts.

Abnormal morphology and subcortical projections to the medial geniculate in an animal model of autism

Auditory dysfunction, including hypersensitivity and tinnitus, is a common symptom of autism spectrum disorder (ASD). Prenatal exposure to the antiseizure medication valproic acid (VPA) significantly increases the risk of ASD in humans and similar exposure is utilized as an animal model of ASD in rodents. Animals exposed to VPA in utero have abnormal activity in their auditory cortex in response to sounds, fewer neurons, abnormal neuronal morphology, reduced expression of calcium-binding proteins, and reduced ascending projections to the central nucleus of the inferior colliculus. Unfortunately, these previous studies of central auditory circuits neglect the medial geniculate (MG), which serves as an important auditory relay from the midbrain to the auditory cortex. Here, we examine the structure and connectivity of the medial geniculate (MG) in rats prenatally exposed to VPA. Our results indicate that VPA exposure results in significantly smaller and fewer neurons in the ventral and medial nuclei of the MG. Furthermore, injections of the retrograde tract tracer fluorogold (FG) in the MG result in significantly fewer FG+ neurons in the inferior colliculus, superior olivary complex, and ventral cochlear nucleus. Together, we interpret these findings to indicate that VPA exposure results in hypoplasia throughout the auditory circuits and that VPA has a differential impact on some long-range axonal projections from brainstem centers to the thalamus. Together, our findings support the widespread impact of VPA on neurons and sensory circuits in the developing brain.

Relationship Between Early Social-Emotional Behavior and Autism Spectrum Disorder: A High-Risk Sibling Study

Social-emotional behavior in autism spectrum disorder (ASD) was examined among high-risk (HR; siblings of children diagnosed with ASD) and low-risk (LR; no family history of ASD) toddlers. Caregivers completed the Infant-Toddler Social Emotional Assessment (ITSEA) at 18 months, and blind diagnostic assessment for ASD was conducted at 36 months. Results indicated impairment in social-emotional functioning among HR toddlers subsequently diagnosed with ASD compared to other HR and LR toddlers, such that ITSEA domains (Internalizing, Dysregulation, Competence) and subdomains predicted later ASD symptoms and diagnosis. Receiver operating curves of optimal ITSEA cutoffs ranged from 0.23 to 0.44 for sensitivity, and 0.74 to 0.89 for specificity. Although classification accuracy for ASD was limited, group differences highlight the importance of considering social-emotional development when assessing ASD risk.

Age of First Walking and Associations with Symptom Severity in Children with Suspected or Diagnosed Autism Spectrum Disorder

Age of first walking (AOW) is reported to be later in autism spectrum disorder (ASD) compared with typical development. However, the relationship between AOW and variations in ASD symptoms across different neurodevelopmental disorders is largely unknown. This study investigated AOW and its association with autism symptom severity in a large sample of children (N = 490, 23% females) clinically evaluated for suspected ASD, differentiated into ASD (n = 376) and non-ASD (n = 114) diagnoses. Children with ASD achieved independent walking significantly later than children with non-ASD diagnoses. AOW was significantly associated with ASD symptom severity, and females had a non-significant later AOW. The current findings suggest that in cases with delayed AOW, ASD should be considered as an actual differential diagnosis, perhaps particularly in girls.

Research Review: Do parent ratings of infant negative emotionality and self-regulation predict psychopathology in childhood and adolescence? A systematic review and meta-analysis of prospective longitudinal studies

BACKGROUND

Identifying low-cost and easy to implement measures of infant markers of later psychopathology may improve targeting of early intervention for prevention. Because of their early manifestation, relative stability and overlap with constructs central to affect-based dimensions of child and adolescent psychopathology, negative emotionality and self-regulation have been the focus of this research. We conducted a meta-analysis of longitudinal studies examining the prospective association between infant temperament measured with parent ratings and child/adolescent psychopathology.

METHODS

A systematic literature search for prospective longitudinal studies, which included measures of questionnaire-assessed infant temperament (negative emotionality, self-regulation, behavioural inhibition, surgency/extraversion, activity level) and symptoms of child or adolescent mental health (externalising, internalising) and neurodevelopmental problems (attention deficit/hyperactivity disorder [ADHD], autism spectrum disorder [ASD]), was conducted. Standardised estimates of association were calculated and pooled in meta-analyses.

RESULTS

Twenty-five studies (n = 28,425) met inclusion criteria. Small associations were seen between psychopathology aggregated across all domains and infant negative emotionality (r = .15; p < .001) and self-regulation (r = -.19; p = .007). Effects were also significant but weaker for behavioural inhibition (r = .10; p = .027) and activity level (r = .08; p = .016). Surgency/extraversion was not significantly associated with psychopathology in general (r = -.04; p = .094); however, it was negatively associated with ASD (r = -.10, p = .015). Significant correlations were observed with some outcomes isomorphic with predictors, internalising problems and behavioural inhibition (r = .10; p = .013), ADHD symptoms and activity level (r = .19; p = .009).

CONCLUSION

Questionnaire-based assessments of infant negative emotionality may have transdiagnostic potential to contribute to a risk index of later childhood psychopathology. Behavioural inhibition, surgency/extraversion and activity ratings may provide more specific predictive power. More data from prospective studies are required before the potential of self-regulation and surgency/extraversion can be properly gauged.

Polygenic Risk Scores for Developmental Disorders, Neuromotor Functioning During Infancy, and Autistic Traits in Childhood

BACKGROUND

Impaired neuromotor development is often one of the earliest observations in children with autism spectrum disorder (ASD). We investigated whether a genetic predisposition to developmental disorders was associated with nonoptimal neuromotor development during infancy and examined the genetic correlation between nonoptimal neuromotor development and autistic traits in the general population.

METHODS

In a population-based cohort in The Netherlands (2002-2006), we calculated polygenic risk scores (PRSs) for ASD and attention-deficit/hyperactivity disorder (ADHD) using genome-wide association study summary statistics. In 1921 children with genetic data, parents rated autistic traits at 6 years of age. Among them, 1174 children (61.1%) underwent neuromotor examinations (tone, responses, senses, and other observations) during infancy (9-20 weeks of age). We used linear regressions to examine associations of PRSs with neuromotor scores and autistic traits. We performed a bivariate genome-based restricted maximum likelihood analysis to explore whether genetic susceptibility underlies the association between neuromotor development and autistic traits.

RESULTS

Higher PRSs for ASD were associated with less optimal overall infant neuromotor development, in particular low muscle tone. Higher PRSs for ADHD were associated with less optimal senses. PRSs for ASD and those for ADHD both were associated with autistic traits. The single nucleotide polymorphism-based heritability of overall motor development was 20% (SE = .21) and of autistic traits was 68% (SE = .26). The genetic correlation between overall motor development and autistic traits was .35 (SE = .21, p < .001).

CONCLUSIONS

We found that genetic liabilities for ASD and ADHD covary with neuromotor development during infancy. Shared genetic liability might partly explain the association between nonoptimal neuromotor development during infancy and autistic traits in childhood.

Structural and Functional Aberrations of the Auditory Brainstem in Autism Spectrum Disorder

Autism spectrum disorder (ASD) is a neurodevelopmental condition associated with difficulties in the social, communicative, and behavioral domains. Most cases of ASD arise from an unknown etiologic process, but there are numerous risk factors, including comorbidities and maternal exposures. Although it is not part of the diagnostic criteria, hearing difficulties ranging from deafness to hyperacusis are present in the majority of persons with ASD. High-functioning children with ASD have been found to have significantly slower and asymmetric auditory brainstem reflexes. Additionally, histopathological studies of postmortem brainstems in decedents who had ASD have consistently revealed significantly fewer neurons in auditory nuclei compared with those in people who did not have ASD. The authors review the literature implicating auditory dysfunction in ASD along with results from human study participants and postmortem human brain tissue. Together, these results implicate significant structural and functional abnormalities in the auditory brainstem in ASD and support the utility of auditory testing to screen for ASD.

Pre-emptive Intervention for Autism Spectrum Disorder: Theoretical Foundations and Clinical Translation

Autism spectrum disorders (ASD) are an emergent public health problem, placing significant burden upon the individual, family and health system. ASD are polygenetic spectrum disorders of neural connectome development, in which one or more feedback loops amplify small genetic, structural, or functional variations in the very early development of motor and sensory-motor pathways. These perturbations trigger a 'butterfly effect' of unpredictable cascades of structural and functional imbalances in the global neuronal workspace, resulting in atypical behaviors, social communication, and cognition long-term. The first 100 days post-term are critically neuroplastic and comprise an injury-sensitive developmental window, characterized by a neural biomarker, the persistence of the cortical subplate, and a behavioral biomarker, the crying diathesis. By the time potential diagnostic signs are identified, from 6 months of age, ASD neuropathy is already entrenched. The International Society for Autism Research Special Interest Group has called for pre-emptive intervention, based upon rigorous theoretical frames, and real world translation and evaluation. This paper responds to that call. It synthesizes heterogenous evidence concerning ASD etiologies from both psychosocial and biological research literatures with complexity science and evolutionary biology, to propose a theoretical framework for pre-emptive intervention. This paper hypothesizes that environmental factors resulting from a mismatch between environment of evolutionary adaptedness and culture initiate or perpetuate early motor and sensory-motor lesions, triggering a butterfly effect of multi-directional cascades of atypical developmental in the complex adaptive system of the parent and ASD-susceptible infant. Chronic sympathetic nervous system/hypothalamic-pituitary-adrenal axis hyperarousal and disrupted parent-infant biobehavioral synchrony are the key biologic and behavioral mechanisms perpetuating these atypical developmental cascades. A clinical translation of this evidence is proposed, for application antenatally and in the first 6 months of life, as pre-emptive intervention for ASD.

Effectiveness of Noise-Attenuating Headphones on Physiological Responses for Children With Autism Spectrum Disorders

Objective: The purpose of this study was to evaluate the proof of concept of an intervention to decrease sympathetic activation as measured by skin conductivity (electrodermal activity, EDA) in children with an autism spectrum disorder (ASD) and auditory hypersensitivity (hyperacusis). In addition, researchers examined if the intervention provided protection against the negative effects of decibel level of environmental noises on electrodermal measures between interventions. The feasibility of implementation and outcome measures within natural environments were evaluated.

Method: A single-subject multi-treatment design was used with six children, aged 8–16 years, with a form of Autism (i.e., Autism, PDD-NOS). Participants used in-ear (IE) and over-ear (OE) headphones for two randomly sequenced treatment phases. Each child completed four phases: (1) a week of baseline data collection; (2) a week of an intervention; (3) a week of no intervention; and (4) a week of the other intervention. Empatica E4 wristbands collected EDA data. Data was collected on 16–20 occasions per participant, with five measurements per phase.

Results: Separated tests for paired study phases suggested that regardless of intervention type, noise attenuating headphones led to a significance difference in both skin conductance levels (SCL) and frequency of non-specific conductance responses (NS-SCRs) between the baseline measurement and subsequent phases. Overall, SCL and NS-SCR frequency significantly decreased between baseline and the first intervention phase. A protective effect of the intervention was tested by collapsing intervention results into three phases. Slope correlation suggested constant SCL and NS-SCR frequency after initial use of the headphones regardless of the increase in environmental noises. A subsequent analysis of the quality of EDA data identified that later phases of data collection were associated with better data quality.

Conclusion: Many children with ASD have hypersensitivities to sound resulting in high levels of sympathetic nervous system reactivity, which is associated with problematic behaviors and distress. The findings of this study suggest that the use of noise attenuating headphones for individuals with ASD and hyperacusis may reduce sympathetic activation. Additionally, results suggest that the use of wearable sensors to collect physiological data in natural environments is feasible with established protocols and training procedures.

Deviations from Typical Developmental Trajectories Detectable at 9 Months of Age in Low Risk Children Later Diagnosed with Autism Spectrum Disorder

This study was designed to track the developmental trajectory, during the first 24 months of life, of 335 low-risk infants later diagnosed with Autism Spectrum Disorder and identify early deviations observed in routine Well Care checkups. We compared their achievements to typically developing children and to children later diagnosed with non-autistic developmental impairments. The results show that in the first 6 months, the children with autism showed normal acquisition of milestones, whereas by 9 months of age they began to fail the language/communication, as well as motor items when compared to typical and delayed non-autistic children. Regular check-up visits may be useful in detecting early failure in achieving milestones, leading to earlier referral for further evaluation and treatment.

Recognising autism: a latent transition analysis of parental reports of child autistic spectrum disorder 'red flag' traits before and after age 3

PURPOSE

It has been proposed that parents should be educated about child autistic spectrum disorder (ASD) 'red flag' traits to help professionals identify and address concerning behaviours as early as possible. This study aimed to empirically demonstrate that established/recognised 'red flag' traits in the first 3 years of life would reliably predict ASD risk severity in later childhood, associated with established ASD risk correlates and mirroring functioning diagnostic categories.

METHODS

Using retrospective parental report data from the Mental Health of Children and Young People in Great Britain survey (N = 7977), latent class analysis (LCA) and a quasi -latent transition analysis were used to (1) identify profiles of variation in parent reports of child 'red flag' traits before and after age 3 and (2) model transitions in risk from 3 years and below to ≥ 3 years, respectively, per the 'optimal outcome' model.

RESULTS

Three distinct classes, each characterised by variation in parent 'red flag' trait reporting were identified for the '≤ 3 years of age' and the '≥ 3 years of age' data. Both LCA class profiles comprised groups of children characterised by low, medium and high ASD risk. Dose-response effects for a number of recognised ASD correlates across the low, moderate and high risk '≥ 3 years of age' classes seemed to validate older classes in terms of ASD relevance. Over 54% of children characterised by the highest levels of ASD 'red flag' trait probability at 3 years and below (2% of sample), also populated the high-risk class evidenced in the '≥ 3 years of age' LCA.

CONCLUSIONS

Retrospective parental reports of child ASD 'red flag' traits ≤ 3 years of age were reliable indicators of ASD risk in later childhood.

Variability in Verbal and Nonverbal Communication in Infants at Risk for Autism Spectrum Disorder: Predictors and Outcomes

Early communication impairment is among the most-reported first concerns in parents of young children with autism spectrum disorder (ASD). Using a parent-report questionnaire, we derived trajectory groups for early language and gesture acquisition in siblings at high risk for ASD and in children at low risk, during their first 2 years of life. Developmental skills at 6 months were associated with trajectory group membership representing growth in receptive language and gestures. Behavioral symptoms also predicted gesture development. All communication measures were strongly related to clinical and developmental outcomes. Trajectory groups further indicated slowest language/gesture acquisition in infants with later ASD diagnoses, in particular when associated with language delay. Overall, our results confirm considerable variability in communication development in high-risk infants.

Temperament as an Early Risk Marker for Autism Spectrum Disorders? A Longitudinal Study of High-Risk and Low-Risk Infants

To investigate temperament as an early risk marker for autism spectrum disorder (ASD), we examined parent-reported temperament for high-risk (HR, n = 170) and low-risk (LR, n = 77) siblings at 8, 14, and 24 months. Diagnostic assessment was performed at 36 months. Group-based analyses showed linear risk gradients, with more atypical temperament for HR-ASD, followed by HR-Atypical, HR-Typical, and LR siblings. Temperament differed significantly between outcome groups (0.03 ≤ ηp2 ≤ 0.34). Machine learning analyses showed that, at an individual level, HR-ASD siblings could not be identified accurately, whereas HR infants without ASD could. Our results emphasize the discrepancy between group-based and individual-based predictions and suggest that while temperament does not facilitate early identification of ASD individually, it may help identify HR infants who do not develop ASD.