Sleep Problems and Trajectories of Restricted and Repetitive Behaviors in Children with Neurodevelopmental Disabilities

Developing forebrain synapses are uniquely vulnerable to sleep loss

Sleep is an essential behavior that supports lifelong brain health and cognition. Neuronal synapses are a major target for restorative sleep function and a locus of dysfunction in response to sleep deprivation (SD). Synapse density is highly dynamic during development, becoming stabilized with maturation to adulthood, suggesting sleep exerts distinct synaptic functions between development and adulthood. Importantly, problems with sleep are common in neurodevelopmental disorders including autism spectrum disorder (ASD). Moreover, early life sleep disruption in animal models causes long lasting changes in adult behavior. Different plasticity engaged during sleep necessarily implies that developing and adult synapses will show differential vulnerability to SD. To investigate distinct sleep functions and mechanisms of vulnerability to SD across development, we systematically examined the behavioral and molecular responses to acute SD between juvenile (P21-28), adolescent (P42-49) and adult (P70-100) mice of both sexes. Compared to adults, juveniles lack robust adaptations to SD, precipitating cognitive deficits in the novel object recognition test. Subcellular fractionation, combined with proteome and phosphoproteome analysis revealed the developing synapse is profoundly vulnerable to SD, whereas adults exhibit comparative resilience. SD in juveniles, and not older mice, aberrantly drives induction of synapse potentiation, synaptogenesis, and expression of peri-neuronal nets. Our analysis further reveals the developing synapse as a convergent node between vulnerability to SD and ASD genetic risk. Together, our systematic analysis supports a distinct developmental function of sleep and reveals how sleep disruption impacts key aspects of brain development, providing mechanistic insights for ASD susceptibility.

Sleep and Autism: Current Research, Clinical Assessment, and Treatment Strategies

Autism spectrum disorder is associated with a high rate of sleep problems, affecting over 80% of autistic individuals. Sleep problems have pervasive negative effects on health, behavior, mood, and cognition but are underrecognized in autistic children. Problems initiating and maintaining sleep-hallmarks of insomnia-are common. Sleep-disordered breathing and restless legs syndrome have also been described in autism at a higher prevalence than in community populations. The authors describe current research on sleep in autistic children and potential pathophysiologic mechanisms. They describe practical approaches to sleep assessment and synthesize approaches to addressing sleep problems in autistic children.

Trajectory research in children with an autism diagnosis: A scoping review

LAY ABSTRACT

The types of outcomes studied in children on the autism spectrum include clinical characteristics, such as social functioning, communication, language, or autism symptoms. Research that measures these outcomes at multiple timepoints is useful to improve our understanding of what to expect as children develop. In trajectory studies, researchers assess outcomes at three or more timepoints. This method has advantages over two-timepoint studies because it allows researchers to describe changes in the speed of development, such as accelerations, plateaus, or slowdowns. We identified and reviewed 103 published trajectory studies in children (to age 18 years) with an autism diagnosis. Importantly, we did not include studies of treatments or their effects, nor did we summarize the results of studies. Instead, this review summarizes the characteristics of the available published research, including the methods used, the many different outcomes that have been studied over time and the ages over which they have been studied. This summary may be of interest to autistic people and caregivers (parents) who want to know about the existence of research that provides answers about what to expect during an autistic child's development. We have recommended that future trajectory research efforts try to make up for the lack of studies from low- and middle-income countries; that more attention is given to the following outcomes that are meaningful to caregivers and autistic people; and to try to fill in the age gaps where more outcome-specific data are needed.

Sleep Problems Before and During the COVID-19 Pandemic in Children with Autism Spectrum Disorder, Down Syndrome, and Typical Development

Sleep problems are common in children and adolescents, particularly those with Neurodevelopmental Disorders. With the changes in daily habits resulting from the COVID-19 pandemic, we have analyzed sleep characteristics, during social isolation, in Brazilian children and adolescents aged between 4 and 12 years with Autism Spectrum Disorder (N = 267), Down Syndrome (N = 74), and typical development (N = 312). The ASD group presented with worse indicators of sleep habits in the Children's Sleep Habits Questionnaire (CSHQ-BR) and fell asleep later during the pandemic. The entire group started fall asleep and waking up later during the pandemic - as well as waking up more often during the night. These results may contribute to parental guidance and sleep habit-related interventions during and after the COVID-19 pandemic.

Children with Autism Spectrum Disorder and Abnormalities of Clinical EEG: A Qualitative Review

Over the last decade, the comorbidity between Autism Spectrum Disorder (ASD) and epilepsy has been widely demonstrated, and many hypotheses regarding the common neurobiological bases of these disorders have been put forward. A variable, but significant, prevalence of abnormalities on electroencephalogram (EEG) has been documented in non-epileptic children with ASD; therefore, several scientific studies have recently tried to demonstrate the role of these abnormalities as a possible biomarker of altered neural connectivity in ASD individuals. This narrative review intends to summarize the main findings of the recent scientific literature regarding abnormalities detected with standard EEG in children/adolescents with idiopathic ASD. Research using three different databases (PubMed, Scopus and Google Scholar) was conducted, resulting in the selection of 10 original articles. Despite an important lack of studies on preschoolers and a deep heterogeneity in results, some authors speculated on a possible association between EEG abnormalities and ASD characteristics, in particular, the severity of symptoms. Although this correlation needs to be more strongly elucidated, these findings may encourage future studies aimed at demonstrating the role of electrical brain abnormalities as an early biomarker of neural circuit alterations in ASD, highlighting the potential diagnostic, prognostic and therapeutic value of EEG in this field.

Critical periods and Autism Spectrum Disorders, a role for sleep

Brain development relies on both experience and genetically defined programs. Time windows where certain brain circuits are particularly receptive to external stimuli, resulting in heightened plasticity, are referred to as "critical periods". Sleep is thought to be essential for normal brain development. Importantly, studies have shown that sleep enhances critical period plasticity and promotes experience-dependent synaptic pruning in the developing mammalian brain. Therefore, normal plasticity during critical periods depends on sleep. Problems falling and staying asleep occur at a higher rate in Autism Spectrum Disorder (ASD) relative to typical development. In this review, we explore the potential link between sleep, critical period plasticity, and ASD. First, we review the importance of critical period plasticity in typical development and the role of sleep in this process. Next, we summarize the evidence linking ASD with deficits in synaptic plasticity in rodent models of high-confidence ASD gene candidates. We then show that the high-confidence rodent models of ASD that show sleep deficits also display plasticity deficits. Given how important sleep is for critical period plasticity, it is essential to understand the connections between synaptic plasticity, sleep, and brain development in ASD. However, studies investigating sleep or plasticity during critical periods in ASD mouse models are lacking. Therefore, we highlight an urgent need to consider developmental trajectory in studies of sleep and plasticity in neurodevelopmental disorders.

Loss of sleep when it is needed most - Consequences of persistent developmental sleep disruption: A scoping review of rodent models

Sleep is an essential component of development. Developmental sleep disruption (DSD) impacts brain maturation and has been associated with significant consequences on socio-emotional development. In humans, poor sleep during infancy and adolescence affects neurodevelopmental outcomes and may be a risk factor for the development of autism spectrum disorder (ASD) or other neuropsychiatric illness. Given the wide-reaching and enduring consequences of DSD, identifying underlying mechanisms is critical to best inform interventions with translational capacity. In rodents, studies have identified some mechanisms and neural circuits by which DSD causes later social, emotional, sensorimotor, and cognitive changes. However, these studies spanned methodological differences, including different developmental timepoints for both sleep disruption and testing, different DSD paradigms, and even different rodent species. In this scoping review on DSD in rodents, we synthesize these various studies into a cohesive framework to identify common neural mechanisms underlying DSD-induced dysfunction in brain and behavior. Ultimately, this review serves the goal to inform the generation of novel translational interventions for human developmental disorders featuring sleep disruption.

Sleep disturbances in autism spectrum disorder: Animal models, neural mechanisms, and therapeutics

Sleep is crucial for brain development. Sleep disturbances are prevalent in children with autism spectrum disorder (ASD). Strikingly, these sleep problems are positively correlated with the severity of ASD core symptoms such as deficits in social skills and stereotypic behavior, indicating that sleep problems and the behavioral characteristics of ASD may be related. In this review, we will discuss sleep disturbances in children with ASD and highlight mouse models to study sleep disturbances and behavioral phenotypes in ASD. In addition, we will review neuromodulators controlling sleep and wakefulness and how these neuromodulatory systems are disrupted in animal models and patients with ASD. Lastly, we will address how the therapeutic interventions for patients with ASD improve various aspects of sleep. Together, gaining mechanistic insights into the neural mechanisms underlying sleep disturbances in children with ASD will help us to develop better therapeutic interventions.

Sleep problems in autism: Sex differences in the school-age population

Clinically significant sleep problems affect up to 86% of the autistic population in school-age. Sleep problems can have negative impacts on child cognition, behavior, and health. However, sex differences in the prevalence and types of sleep problems are not well understood in autism. To evaluate sex differences in sleep problems in the school-age autistic population, we obtained parent-report of sleep problems on the Children's Sleep Habits Questionnaire and conducted direct assessments to establish diagnosis and intellectual ability in 6-12-year-old children (autism n = 250; typical development [TD] n = 114). Almost 85% of autistic females demonstrated sleep problems compared to 65.8% of autistic males, 44.8% of TD females, and 42.4% of TD males; a statistically significant increase for autistic females. Autistic females demonstrated increased bedtime resistance, sleep anxiety, and sleepiness, and decreased sleep duration, but did not differ in sleep onset delay, night wakings, parasomnias, or disordered breathing compared with autistic males. Intellectual ability was not related to increased sleep problems. Higher anxiety scores were associated with more sleep problems for males but not females. In one of the first studies to evaluate sex differences in sleep in the school-age, autistic population, autistic females demonstrated increased sleep problems compared to autistic males, TD females, and TD males. Current autism assessment and intervention practices may benefit from increased attention to sleep problems in autistic school-age females and to anxiety in autistic males to enhance well-being and behavioral and health outcomes.

Sleep, plasticity, and sensory neurodevelopment

A defining feature of early infancy is the immense neural plasticity that enables animals to develop a brain that is functionally integrated with a growing body. Early infancy is also defined as a period dominated by sleep. Here, we describe three conceptual frameworks that vary in terms of whether and how they incorporate sleep as a factor in the activity-dependent development of sensory and sensorimotor systems. The most widely accepted framework is exemplified by the visual system where retinal waves seemingly occur independent of sleep-wake states. An alternative framework is exemplified by the sensorimotor system where sensory feedback from sleep-specific movements activates the brain. We prefer a third framework that encompasses the first two but also captures the diverse ways in which sleep modulates activity-dependent development throughout the nervous system. Appreciation of the third framework will spur progress toward a more comprehensive and cohesive understanding of both typical and atypical neurodevelopment.

Early life sleep disruption potentiates lasting sex-specific changes in behavior in genetically vulnerable Shank3 heterozygous autism model mice

Background

Patients with autism spectrum disorder (ASD) experience high rates of sleep disruption beginning early in life; however, the developmental consequences of this disruption are not understood. We examined sleep behavior and the consequences of sleep disruption in developing mice bearing C-terminal truncation mutation in the high-confidence ASD risk gene SHANK3 (Shank3ΔC). We hypothesized that sleep disruption may be an early sign of developmental divergence, and that clinically relevant Shank3^WT/ΔC mice may be at increased risk of lasting deleterious outcomes following early life sleep disruption.

Methods

We recorded sleep behavior in developing Shank3^ΔC/ΔC, Shank3^WT/ΔC, and wild-type siblings of both sexes using a noninvasive home-cage monitoring system. Separately, litters of Shank3^WT/ΔC and wild-type littermates were exposed to automated mechanical sleep disruption for 7 days prior to weaning (early life sleep disruption: ELSD) or post-adolescence (PASD) or undisturbed control (CON) conditions. All groups underwent standard behavioral testing as adults.

Results

Male and female Shank3^ΔC/ΔC mice slept significantly less than wild-type and Shank3^WT/ΔC siblings shortly after weaning, with increasing sleep fragmentation in adolescence, indicating that sleep disruption has a developmental onset in this ASD model. ELSD treatment interacted with genetic vulnerability in Shank3^WT/ΔC mice, resulting in lasting, sex-specific changes in behavior, whereas wild-type siblings were largely resilient to these effects. Male ELSD Shank3^WT/ΔC subjects demonstrated significant changes in sociability, sensory processing, and locomotion, while female ELSD Shank3^WT/ΔC subjects had a significant reduction in risk aversion. CON Shank3^WT/ΔC mice, PASD mice, and all wild-type mice demonstrated typical behavioral responses in most tests.

Limitations

This study tested the interaction between developmental sleep disruption and genetic vulnerability using a single ASD mouse model: Shank3ΔC (deletion of exon 21). The broader implications of this work should be supported by additional studies using ASD model mice with distinct genetic vulnerabilities.

Conclusion

Our study shows that sleep disruption during sensitive periods of early life interacts with underlying genetic vulnerability to drive lasting and sex-specific changes in behavior. As individuals progress through maturation, they gain resilience to the lasting effects of sleep disruption. This work highlights developmental sleep disruption as an important vulnerability in ASD susceptibility.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13229-022-00514-5.

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

Background

COVID-19 restrictive measures have had a considerable impact on daily life routines, which may be especially challenging for families of children with autism. In pre-schoolers with autism, it is likely that the disruption of routines mainly impacts the presence of restrictive and repetitive behaviours (RRBs). Furthermore, influence of comorbid conditions, secondary behavioural difficulties and home environment characteristics on RRBs was explored.

Method

A cross-sectional online survey design was used to collect parent-report data on 254 children with autism (2.5–6 years) during lockdown in the early months of the pandemic. RRBs were assessed using the Repetitive Behaviour Scale-Revised (RBS-R).

Results

Parents reported a significant increase in stereotypic, self-injurious, compulsive and ritualistic behaviour, and restricted interests after implementation of COVID-19 restrictions. The presence of a co-occurring condition, such as language impairments or intellectual disability, was associated with more self-injurious and stereotypic behaviour. However, there was no effect of home environment on RRBs. Further, most children showed increases in internalising and/or externalising behaviour. Increased inattentive behaviour was associated with more ritualistic and stereotypic behaviour, and restricted interests. Decreases in hyperactivity were related to more restricted interests. Importantly, in a subset of children, parents reported less behavioural difficulties during the lockdown.

Conclusions

Findings highlight the importance of flexible implementation and continuity of care for pre-schoolers with autism and support for parents. Further follow-up of children with autism and RRBs, and co-occurring behavioural difficulties is needed and could enhance our understanding of the long-term effects associated with sudden restrictive measures to daily routines.

Clinical and behavioral attributes leading to sleep disorders in children on the autism spectrum

Sleep disorders are a common comorbid condition in children diagnosed with autism spectrum disorder ("autism"). However, the relationship between the clinical features of autism and sleep disorders remains unclear. A better understanding of the inherent autism-related characteristics linked to comorbid sleep disorders would improve comprehensive assessment and management. This study examined the relationship between sociodemographics, autism symptoms, sleep problems, cognitive status, behavioral attributes, and sensory profiles. Using data from 1268 participants who took part in the Australian Autism Biobank, sleep-related measurements using the Child Sleep Habits Questionnaire (CSHQ) were compared between autistic children aged 2 to 17 (N = 969), their siblings (N = 188), and unrelated children without an autism diagnosis (N = 111). The known relationship between sleep problems and autism was further explored by including scores from the Autism Diagnostic Observation Schedule-2, Mullen Scales of Early Learning, Vineland Adaptive Behavioral Scale-II and the Short Sensory Profile-2; which were included in analyses for autistic participants who had a completed CSHQ. Multiple regression models were used to identify clinical/behavioral variables associated with CSHQ subscales. The autism group had a significantly higher total CSHQ score than the sibling and comparison groups (p < 0.001), indicating worse sleep quality. Within the autism group, lower adaptive behaviors (i.e., VABS-II) and sensory issues (i.e., SSP-2 subclass scores) were positively associated with the severity of sleep problems (i.e., the CSHQ subclass scores) (p < 0.001). The significant functional impact of poor sleep on autistic children warrants an assessment of sleep as a critical part of a holistic approach to supporting autistic children and their families. LAY SUMMARY: Autistic children generally have co-occurring conditions. Sleep disorders impact approximately 50%-80% of autistic children. The impact on the quality of life for both the children and their families can be significant. This study compares sleep problems in autistic children and adolescents with their siblings and children without a diagnosis of autism, and investigates the relationship between specific autistic traits, daily life behaviors and sleep problems. The findings highlight the importance of a holistic assessment for autistic children and matching appropriate sleep intervention and supports where indicated.

Examining the Relationship Between Sleep Quality, Social Functioning, and Behavior Problems in Children with Autism Spectrum Disorder: A Systematic Review

Over forty percent of autistic children experience poor sleep quality, and social interaction difficulties are a core characteristic of autism. However, the relationship between sleep quality and social functioning and behavior remains poorly understood. This systematic review examined the evidence concerning the impact of sleep quality on the social functioning and behavior problems in autistic children and adolescents. It also identified key related factors and evaluated how this issue has been researched to date. Seven key journals were hand-searched and five databases were systematically searched, using keywords. Titles and abstracts of 4123 items were screened against eligibility criteria by two researchers. Relevant studies were retained if they were peer-reviewed empirical papers, published in English between 2000 and 2021. Then, the full text of 97 papers was screened and if they met the eligibility criteria, their reference lists were hand-searched. Forty-six studies were included in the final review. Data were systematically extracted and two authors critically appraised the strengths and weaknesses of studies using Critical Appraisal Skills Programme tools. Key themes were identified, because a meta-analysis was not possible due to the studies' heterogeneity. The review identified that sleep quality and social functioning are associated with one another and there is a small amount of evidence that a bi-directional causal relationship may exist. Evidence suggests that several nights of suboptimal sleep duration and a lack of deep continuous sleep negatively impact externalizing and internalizing behavior. Sleep quality is also reduced by anxiety and sensory sensitivity. However, longitudinal studies with larger samples are needed to establish causality. Future research needs to examine confounding factors and to develop consensus regarding best-practice processes for the objective measurement of sleep with autistic children. Additional research also needs to further examine the consequences of poor sleep quality on internalizing behavior, and the impact of socio-cultural practices.

Sleep in Children with Autism Spectrum Disorder: A Narrative Review and Systematic Update

Purpose of Review

Sleep problems are a common comorbidity for children with autism spectrum disorder (ASD), and research in this area has a relatively long history. Within this review, we first outline historic patterns in the field of sleep and ASD. Second, we conducted a systematic update and coded these studies based on their alignment with historic patterns. Research on ASD and sleep over the past two decades has primarily focused on four principal areas: (1) documenting the prevalence and types of sleep problems; (2) sleep problem treatment options and efficacy; (3) how sleep problems are associated with other behavioral, contextual, or biological elements; and (4) the impact of child sleep problems on families and care providers. The systematic update in this paper includes empirical studies published between 2018 and 2021 with terms for sleep and ASD within the title, keywords, or abstract.

Recent Findings

In sum, 60 studies fit the inclusion/exclusion criteria and most fit within the historic patterns noted above. Notable differences included more global representation in study samples, studies on the impacts of COVID-19, and a growing body of work on sleep problems as an early marker of ASD. The majority of studies focus on correlates of sleep problems noting less optimal behavioral, contextual, and biological elements are associated with sleep problems across development for children with ASD.

Summary

Recommendations for future directions include continued expansion of global and age representation across samples, a shift toward more treatment and implementation science, and studies that inform our mechanistic understanding of how sleep and ASD are connected.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40675-022-00234-5.

Adverse Effects of the COVID-19 Pandemic on Movement and Play Behaviours of Children and Youth Living with Disabilities: Findings from the National Physical Activity Measurement (NPAM) Study

All children and youth require ample physical activity (PA), low levels of sedentary behaviour (SB), and adequate sleep to stay healthy. Children and youth living with disabilities (CYWD) tend to have fewer opportunities for participation in PA and outdoor play compared with their typically developing peers. In turn, CYWD are typically less active and more sedentary, on average, compared with their peers. The COVID-19 pandemic reduced opportunities for many children and youth to participate in PA and outdoor play. The purpose of this study was to assess parent-perceived changes in PA (including outdoor play), SB (including screen time), and sleep quality and quantity, due to COVID-19 and related restrictions, in a national cohort of Canadian CYWD. We recruited parents of school-aged CYWD (N = 151) in May 2020. In an online survey, parents reported their child's previous 7-day PA, SB, and sleep, as well as perceived changes in their child's movement and play behaviours due to COVID-19 and related restrictions. Parent-perceived parental support for their child's movement and play behaviours during the pandemic was also assessed. We used descriptive statistics to describe the child's movement behaviours and assessed the association between movement behaviours and parental factors using Pearson and point-biserial correlations. Few (5.3%) CYWD met PA recommendations and 13.2% met screen time recommendations during the acute period of the COVID-19 pandemic. More CYWD (66.2%) were meeting sleep recommendations. Overall, only 1.3% of CYWD were meeting the combined movement guidelines. Parent encouragement was positively associated with the child's outdoor PA (0.23), wheeling, walking, and biking (0.19), indoor PA (0.16), and family-based PA (0.26). Parental co-play was similarly positively associated with the child's outdoor PA (0.26), wheeling, walking, and biking (0.39), indoor PA (0.16), and family-based PA (0.26). Parents perceived their CYWD to be less active and more sedentary as a result of COVID-19 and the related restrictions. Parents of CYWD have an important role in encouraging healthy movement behaviours. Return to movement and play post-COVID guidelines should include tailored strategies for CYWD and their families to mitigate the negative impacts of the pandemic.

Activated PI3Kδ syndrome, an immunodeficiency disorder, leads to sensorimotor deficits recapitulated in a murine model

The phosphoinositide-3-kinase (PI3K) family plays a major role in cell signaling and is predominant in leukocytes. Gain-of-function (GOF) mutations in the PIK3CD gene lead to the development of activated PI3Kδ syndrome (APDS), a rare primary immunodeficiency disorder. A subset of APDS patients also displays neurodevelopmental delay symptoms, suggesting a potential role of PIK3CD in cognitive and behavioural function. However, the extent and nature of the neurodevelopmental deficits has not been previously quantified. Here, we assessed the cognitive functions of two APDS patients, and investigated the causal role of the PIK3CD GOF mutation in neurological deficits using a murine model of this disease. We used p110δ^E1020K knock-in mice, harbouring the most common APDS mutation in patients. We found that APDS patients present with visuomotor deficits, exacerbated by autism spectrum disorder comorbidity, whereas p110δ^E1020K mice exhibited impairments in motor behaviour, learning and repetitive behaviour patterning. Our data indicate that PIK3CD GOF mutations increase the risk for neurodevelopmental deficits, supporting previous findings on the interplay between the nervous and the immune system. Further, our results validate the knock-in mouse model, and offer an objective assessment tool for patients that could be incorporated in diagnosis and in the evaluation of treatments.