Enhanced cortisol response to stress in children in autism

Occupational Therapy Using Zones of Regulation™ Concepts: A Feasibility Study

There is a lack of peer-reviewed research on occupational therapy using Zones of Regulation™ concepts for autistic youth. The purpose of this article is to describe the feasibility of a newly-developed occupational therapy intervention using Zones of Regulation™ concepts (OT-ZOR) for autistic youth. Specifically, we aimed to evaluate: (a) participant recruitment, retention, and attendance; (b) intervention fidelity, safety, and assessment completion; (c) intervention acceptability; and (d) preliminary participant outcomes. A single-arm feasibility study was completed with outcome measures before and after 10 weeks of OT-ZOR. Fourteen autistic youth ages 6 to 13 completed the study. Youth attended 94% of OT-ZOR sessions. Providers achieved 97% fidelity to the intervention. Occupational therapists and caregivers expressed overall satisfaction with the OT-ZOR intervention. Youth demonstrated significant decreases in irritability, hyperactivity, emotional reactivity, and dysphoria. OT-ZOR is feasible to implement, acceptable to providers and caregivers, and may improve self-regulation in autistic youth.

Autism spectrum disorders and the gastrointestinal tract: insights into mechanisms and clinical relevance

Autism spectrum disorders (ASDs) are recognized as central neurodevelopmental disorders diagnosed by impairments in social interactions, communication and repetitive behaviours. The recognition of ASD as a central nervous system (CNS)-mediated neurobehavioural disorder has led most of the research in ASD to be focused on the CNS. However, gastrointestinal function is also likely to be affected owing to the neural mechanistic nature of ASD and the nervous system in the gastrointestinal tract (enteric nervous system). Thus, it is unsurprising that gastrointestinal disorders, particularly constipation, diarrhoea and abdominal pain, are highly comorbid in individuals with ASD. Gastrointestinal problems have also been repeatedly associated with increased severity of the core symptoms diagnostic of ASD and other centrally mediated comorbid conditions, including psychiatric issues, irritability, rigid-compulsive behaviours and aggression. Despite the high prevalence of gastrointestinal dysfunction in ASD and its associated behavioural comorbidities, the specific links between these two conditions have not been clearly delineated, and current data linking ASD to gastrointestinal dysfunction have not been extensively reviewed. This Review outlines the established and emerging clinical and preclinical evidence that emphasizes the gut as a novel mechanistic and potential therapeutic target for individuals with ASD.

The tryptophan catabolite or kynurenine pathway in autism spectrum disorder; a systematic review and meta-analysis

Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by impaired social communication and interaction, as well as rigid and unchanging interests and behaviors. Several studies have reported that activated immune-inflammatory and nitro-oxidative pathways are accompanied by depletion of plasma tryptophan (TRP), increased competing amino acid (CAAs) levels, and activation of the TRP catabolite (TRYCAT) pathway. This study aims to systematically review and meta-analyze data on peripheral TRP, CAAs, TRYCAT pathway activity, and individual TRYCATs, including kynurenine (KYN) and kynurenic acid (KA) levels, in the blood and urine of ASD patients. After extensively searching PubMed, Google Scholar, and SciFinder, a total of 25 full-text papers were included in the analysis, with a total of 6653 participants (3557 people with ASD and 3096 healthy controls). Our results indicate that blood TRP and the TRP/CAAs ratio were not significantly different between ASD patients and controls (standardized mean difference, SMD = -0.227, 95% confidence interval, CI: -0.540; 0.085, and SMD = 0.158, 95% CI: -0.042; 0.359), respectively. The KYN/TRP ratio showed no significant difference between ASD and controls (SMD = 0.001, 95% CI: -0.169; 0.171). Blood KYN and KA levels were not significantly changed in ASD. Moreover, there were no significant differences in urine TRP, KYN, and KA levels between ASD and controls. We could not establish increases in neurotoxic TRYCATs in ASD. In conclusion, this study demonstrates no abnormalities in peripheral blood TRP metabolism, indoleamine 2,3-dioxygenase enzyme (IDO) activity, or TRYCAT production in ASD. Reduced TRP availability and elevated neurotoxic TRYCAT levels are not substantial contributors to ASD's pathophysiology.

Exploring the intersection of autism spectrum disorder and eating disorders: understanding the unique challenges and treatment considerations for autistic women with eating disorders

PURPOSE OF REVIEW

Autistic women struggle with high levels of both autistic eating behaviours and disordered eating behaviours , which might make them particularly vulnerable to develop eating disorders. Research investigating the presence and characteristics of eating disorders in autistic women is however limited, as is research examining the role of autism in the treatment and recovery of an eating disorder in autistic women.

RECENT FINDINGS

The link between autism and eating disorders has mainly been investigated from the field of eating disorder research, with studies finding an overrepresentation of autism or autistic traits in eating disorders populations. Findings also suggest that autism or autistic traits are associated with a more serious presentation of the eating disorders, including a higher chance of a chronic course of the eating disorders. Most studies however lack comprehensive autism assessments, making it difficult to determine the actual prevalence of autism and its role in women with eating disorders.

SUMMARY

Autistic women with an eating disorder seem to suffer from more complex eating disorders and seem to not benefit from current treatment modalities. This could be partly related to specific autism characteristics such as sensory sensitivities, which are not being considered by current treatment protocols. Future research needs to shed light on what underlies the eating behaviours of autistic women with an eating disorder, in order to help to adapt current treatment modalities to meet the unique needs of these women.

The relationship between balance and urinary cortisol and neopterin in autistic children

Autism Spectrum Disorder (ASD) is a neurodevelopmental condition characterized by stereotyped behavior, restricted interests and social/communicative deficits. The physiological etiology of ASD is not currently understood, however recent research has implicated dysregulation of the immune system as a central feature. The interplay between the stress systems, the immune system and the brain has been well-documented and implicated in other psychiatric and neurological disorders. This interplay suggests a role for the hypothalamic-pituitary-adrenal (HPA) axis in the etiology of ASD. We assessed levels of urinary cortisol and neopterin as markers of immune function and HPA activation in a cohort of 50 children from the central Johannesburg region. Additionally, we used the Autism Treatment Evaluation Checklist to assess autistic symptomatology and the Bruininks-Oseretsky Motor Proficiency Test (Second Edition) (BOT-2) to assess motor skills. No relationships were found between cortisol and autistic symptomatology. No relationships were found between neopterin and any of the other measures. However, a relationship was observed between urinary cortisol and performance on balance-related tasks from the BOT-2 (P < 0.05). Our findings support a theory of neurological interconnectedness between postural modulation and activation of the stress system, which has not previously been documented in children with ASD.

Linehan's biosocial model applied to emotion dysregulation in autism: a narrative review of the literature and an illustrative case conceptualization

Emotion dysregulation (ED) is a transdiagnostic difficulty prevalent in autism spectrum condition (ASC). Importantly, recent research has suggested that ED is involved in self-harm and suicidality. Pre-existing models on the etiology of ED in ASC focus mainly on biological factors to ASC features, such as sensory sensitivities, poor flexibility, and sensitivity to change. However, although psychosocial factors seem to play a role in the emergence of ED in ASC as well (e.g., childhood maltreatment and camouflaging), there is a lack of a comprehensive model conceptualizing biosocial factors involved in ED in autistic people. Linehan's biosocial model (1993) is one of the leading etiological models of ED in borderline personality disorder (BPD). It conceptualizes ED as emerging from transactions between a pre-existing emotional vulnerability in the child and an invalidating developmental environment. Beyond its clinical relevance, Linehan's model has gathered empirical evidence supporting its pertinence in BPD and in other psychiatric disorders. Although ASC and BPD are two distinct diagnoses, because they may share ED, Linehan's biosocial model might be useful for understanding the development of ED in ASC. Hence, this article aims to provide an application and extension of Linehan's model to conceptualize ED in ASC. To do so, we conducted a narrative review of the literature on ED and its underlying factors in ASC from a developmental perspective. To investigate the pertinence of the biosocial model applied to ED in autistic people, we were interested on data on (i) ED and its behavioral correlates in ASC, in relation to the biosocial model, (ii) the potential biological and psychosocial correlates of ED in ASC and (iii) the overlapping difficulties in ASC and BPD. Finally, to assess the pertinence of the model, we applied it to the case of an autistic woman presenting with ED and suicidal behaviors. Our review and application to the case of an autistic woman suggest that ED in ASC encompasses factors related to both biological and psychosocial risk factors as conceptualized in the BPD framework, although in both domains ASC-specific factors might be involved.

Maternal atopic conditions and autism spectrum disorder: a systematic review

Autism spectrum disorder (ASD) is a disabling neurodevelopmental condition with complex etiology. Emerging evidence has pointed to maternal atopy as a possible risk factor. It is hypothesized that maternal atopic disease during pregnancy can lead to increased levels of inflammatory cytokines in fetal circulation via placental transfer or increased production. These cytokines can then pass through the immature blood-brain barrier, causing aberrant neurodevelopment via mechanisms including premature microglial activation. The objective of this study is to systematically review observational studies that investigate whether a maternal history of atopic disease (asthma, allergy, or eczema/atopic dermatitis) is associated with a diagnosis of ASD in offspring. A search was conducted in Ovid MEDLINE, PsycINFO, and Embase databases for relevant articles up to November 2021; this was later updated in January 2022. Observational studies published in peer-reviewed journals were included. Data were synthesized and qualitatively analyzed according to the specific atopic condition. Quality assessment was done using the Newcastle-Ottawa Scale. Nine articles were identified, with all including asthma as an exposure, alongside four each for allergy and eczema. Findings were inconsistent regarding the association between a maternal diagnosis of either asthma, allergy, or eczema, and ASD in offspring, with variations in methodology contributing to the inconclusiveness. More consistent associations were demonstrated regarding maternal asthma that was treated or diagnosed during pregnancy. Evidence suggests that symptomatic maternal asthma during pregnancy could be associated with ASD in offspring, underscoring the importance of effective management of atopic conditions during pregnancy. Further research is needed, particularly longitudinal studies that use gold-standard assessment tools and correlate clinical outcomes with laboratory and treatment data.PROSPERO Registration Number and Date: CRD42018116656, 26.11.2018.

Group Changes in Cortisol and Heart Rate Variability of Children with Down Syndrome and Children with Autism Spectrum Disorder during Dog-Assisted Therapy

Dog-assisted therapy is hypothesized to lower stress in children with autism spectrum disorder (ASD) and children with Down syndrome (DS), which may be visible on a physiological level. In this study, we measured heart rate variability (HRV) and salivary cortisol of 20 children with DS or ASD at the beginning and end of six weekly sessions of dog-assisted therapy. We found a decrease of cortisol levels during single sessions, but no overall effect after six sessions (six weeks). The effect of dog-assisted therapy on the increase of HRV could not be confirmed. This study is one of the first to use physiological measurements to test the effects of DAT.

Using a life course health development framework to combat stigma-related health disparities for individuals with intellectual and/or developmental disability (I/DD)

In the U.S., 1 in 6 children has an intellectual and/or developmental disability (I/DD). This population experiences a multitude of negative health outcomes across the life course, relative to the general population. Stigma-the social devaluation of individuals with certain characteristics, identities, or statuses within interpersonal, educational, healthcare, and policy contexts-is a potentially preventable contributor to health disparities. To date, existing approaches for addressing and preventing stigma are limited to discrete and siloed interventions that often fail to address the lifelong, cumulative impacts of the specific types of stigma experienced by the I/DD population. In the current paper, we describe three elements of Life Course Health Development (LCHD)-a novel translational framework that draws on evidence from biology, sociology, epidemiology, and psychology-that healthcare providers can use to prevent stigma-related health disparities and improve outcomes for individuals with I//DDs. We discuss the utility of targeting prevention to sensitive periods; prioritizing interventions for the most damaging types of stigmas; and leveraging supports from multiple service systems and sectors. By incorporating evidence from life course science into efforts to address stigma-related health disparities, providers can more effectively and strategically prevent and combat stigma-related health disparities for the I/DD population in childhood and across the life course.

Neurophysiological Correlates of Sensory-Based Phenotypes in ASD

Children with autism spectrum disorder frequently present with atypical behavioral responses to sensory stimuli, as well as differences in autonomic nervous system (ANS) and neuroendocrine activity. However, no one consistent pattern appears to explain these differences within this heterogeneous population. To conceptualize more homogenous ASD subgroups, sensory-based subtypes have been explored. One subtyping mechanism groups children by sensory responsivity pattern in addition to sensory domain. Differences in nervous system responsivity to sensory input within this sensory-based subtyping scheme have not yet been investigated. This exploratory study used ANS indices (respiratory sinus arrhythmia [RSA], skin conductance level) and neuroendocrine (salivary cortisol) response to examine patterns differentiating these subtypes. Significant differences in RSA were found during baseline, and during tactile, tone and movement stimuli (p < 0.05). Subtype membership was predicted by RSA changes during auditory stimulation and recovery periods (p < 0.05). Results confirm that children with an adaptive sensory responsivity subtype differ from those children with sensory processing dysfunction, however, physiological variables did not distinguish between children with different patterns of sensory processing dysfunction.

A comparison of stress reactivity between BTBR and C57BL/6J mice: an impact of early-life stress

Early-life stress (ELS) is associated with hypothalamic-pituitary-adrenal (HPA) axis dysregulation and can increase the risk of psychiatric disorders later in life. The aim of this study was to investigate the influence of ELS on baseline HPA axis functioning and on the response to additional stress in adolescent male mice of strains C57BL/6J and BTBR. As a model of ELS, prolonged separation of pups from their mothers (for 3 h once a day: maternal separation [MS]) was implemented. To evaluate HPA axis activity, we assessed serum corticosterone levels and mRNA expression of corticotropin-releasing hormone (Crh) in the hypothalamus, of steroidogenesis genes in adrenal glands, and of an immediate early gene (c-Fos) in both tissues at baseline and immediately after 1 h of restraint stress. HPA axis activity at baseline did not depend on the history of ELS in mice of both strains. After the exposure to the acute restraint stress, C57BL/6J-MS mice showed less pronounced upregulation of Crh and of corticosterone concentration as compared to the control, indicating a decrease in stress reactivity. By contrast, BTBR-MS mice showed stronger upregulation of c-Fos in the hypothalamus and adrenal glands as compared to controls, thus pointing to greater activation of these organs in response to the acute restraint stress. In addition, we noted that BTBR mice are more stress reactive (than C57BL/6J mice) because they exhibited greater upregulation of corticosterone, c-Fos, and Cyp11a1 in response to the acute restraint stress. Taken together, these results indicate strain-specific and situation-dependent effects of ELS on HPA axis functioning and on c-Fos expression.

An integrated perspective for the diagnosis and therapy of neurodevelopmental disorders - From an engineering point of view

Neurodevelopmental disorders (NDDs) are complex conditions with largely unknown pathophysiology. While many NDD symptoms are familiar, the cause of these disorders remains unclear and may involve a combination of genetic, biological, psychosocial, and environmental risk factors. Current diagnosis relies heavily on behaviorally defined criteria, which may be biased by the clinical team's professional and cultural expectations, thus a push for new biological-based biomarkers for NDDs diagnosis is underway. Emerging new research technologies offer an unprecedented view into the electrical, chemical, and physiological activity in the brain and with further development in humans may provide clinically relevant diagnoses. These could also be extended to new treatment options, which can start to address the underlying physiological issues. When combined with current speech, language, occupational therapy, and pharmacological treatment these could greatly improve patient outcomes. The current review will discuss the latest technologies that are being used or may be used for NDDs diagnosis and treatment. The aim is to provide an inspiring and forward-looking view for future research in the field.

The combination of autism and exceptional cognitive ability is associated with suicidal ideation

Autism with co-occurring exceptional cognitive ability is often accompanied by severe internalizing symptoms and feelings of inadequacy. Whether cognitive ability also translates into greater risk for suicidal ideation is unclear. To investigate this urgent question, we examined two samples of high-ability autistic individuals for factors that were predictive of suicidal ideation. In the first sample (N = 1,074 individuals seen at a clinic specializing in gifted/talented youth), we observed a striking excess of parent-reported suicidal ideation in autistic individuals with IQ ≥ 120 (Odds Ratio = 5.9, p=0.0007). In a separate sample of SPARK participants, we confirmed higher rates of suicidal thoughts compared to non-autistic children from the ABCD cohort (combined N = 16,049, Odds Ratio = 6.8, p<2.2e-16), and further that autistic children with suicidal thoughts had significantly higher cognitive ability (p<2.2e-16) than those without. Elevated polygenic scores (PGS) for cognitive performance were associated with increased suicidal thoughts (N = 1,983, Z=2.16,p=0.03), with PGS for educational attainment trending in the same direction (Z=1.4,p=0.17). Notably, similar results were found in parents of these autistic youth, where higher PGS for educational attainment was associated with increasing thoughts of suicide (N = 736, Z=2.28,p=0.02). Taken together, these results suggest that on a phenotypic and genetic level, increasing cognitive ability is an unexpected risk factor for suicidal ideation in individuals diagnosed with, or at risk for autism.

A molecular framework for autistic experiences: Mitochondrial allostatic load as a mediator between autism and psychopathology

Molecular autism research is evolving toward a biopsychosocial framework that is more informed by autistic experiences. In this context, research aims are moving away from correcting external autistic behaviors and toward alleviating internal distress. Autism Spectrum Conditions (ASCs) are associated with high rates of depression, suicidality and other comorbid psychopathologies, but this relationship is poorly understood. Here, we integrate emerging characterizations of internal autistic experiences within a molecular framework to yield insight into the prevalence of psychopathology in ASC. We demonstrate that descriptions of social camouflaging and autistic burnout resonate closely with the accepted definitions for early life stress (ELS) and chronic adolescent stress (CAS). We propose that social camouflaging could be considered a distinct form of CAS that contributes to allostatic overload, culminating in a pathophysiological state that is experienced as autistic burnout. Autistic burnout is thought to contribute to psychopathology via psychological and physiological mechanisms, but these remain largely unexplored by molecular researchers. Building on converging fields in molecular neuroscience, we discuss the substantial evidence implicating mitochondrial dysfunction in ASC to propose a novel role for mitochondrial allostatic load in the relationship between autism and psychopathology. An interplay between mitochondrial, neuroimmune and neuroendocrine signaling is increasingly implicated in stress-related psychopathologies, and these molecular players are also associated with neurodevelopmental, neurophysiological and neurochemical aspects of ASC. Together, this suggests an increased exposure and underlying molecular susceptibility to ELS that increases the risk of psychopathology in ASC. This article describes an integrative framework shaped by autistic experiences that highlights novel avenues for molecular research into mechanisms that directly affect the quality of life and wellbeing of autistic individuals. Moreover, this framework emphasizes the need for increased access to diagnoses, accommodations, and resources to improve mental health outcomes in autism.

REAC Noninvasive Neurobiological Stimulation in Autism Spectrum Disorder for Alleviating Stress Impact

Objectives

Autism spectrum disorder (ASD) symptoms can become more evident because of different factors. Among these, depression, anxiety, and stress play an important role. Additionally, several studies have revealed the impact of the COVID-19 pandemic on participants with ASD. In previous studies, two noninvasive neurobiological stimulation treatments with radio electric asymmetric conveyer (REAC) technology, called neuropostural optimization (NPO) and neuropsychophysical optimization (NPPO), were shown to be effective in improving the subjective response to environmental stressors in the general population and in ASD population. Based on the proven efficacy of REAC NPO and NPPOs treatments in alleviating anxiety, stress, and depression, the purpose of this study is to verify how these treatments can reduce the severity of ASD symptoms expression, which is aggravated by depression, anxiety, and stress. The treatments' effects were perceived by caregivers and assessed by the Autism Treatment Evaluation Checklist (ATEC).

Methods

This study involved 46 children with a previous diagnosis of ASD made using the Autism Diagnostic Observation Schedule and Autism Diagnostic Interview-Revised. The participants received one session of NPO treatment and one NPPOs treatment cycle of 18 sessions, administered within approximately 3 weeks. The Autism Treatment Evaluation Checklist (ATEC) was used to evaluate the efficacy of the REAC treatments. ATEC allows to evaluate four clusters (speech or language communication; sociability; sensory or cognitive awareness; and health/physical/behavior) through a numerical scale that measures increasing levels of ASD severity.

Results

The comparison between the scores of the ATEC administered pre- and post-REAC treatments highlighted an improvement of ASD symptoms in each of the four clusters of ATEC.

Conclusions

The results confirm the usefulness of REAC treatments to optimize the individual response to environmental stressors and reduce the symptomatic expression and deficits present in ASD.

COVID-19 Pandemic and Autism Spectrum Disorder, Consequences to Children and Adolescents - a Systematic Review

In this systematic review, we aimed to identify the impact of the COVID-19 pandemic on children/adolescents with a diagnosis of autism spectrum disorder (ASD). The protocol was registered on PROSPERO CRD42021255848. Articles were selected from PubMed, Embase, and LILACS according to these characteristics: patients from zero to 18 years old, exposed to the COVID-19 pandemic, impact on social communication/interaction and restricted/repetitive behavior domains. The Newcastle-Ottawa Scale was used to assess methodological quality and the risk of bias. Of the 351 articles initially identified, 26 were finally included with information on 8,610 patients. Although the studies were heterogeneous, they indicated that the pandemic-related issues experienced by patients with ASD were mostly manifested in their behavior and sleep patterns.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40489-022-00344-4.

Prenatal valproic acid-induced autism marmoset model exhibits higher salivary cortisol levels

Individuals with autism spectrum disorder (ASD) are exposed to a variety of stressors owing to their behavioral traits. Cortisol is a hormone typically associated with stress, and its concentration and response to stress are higher in individuals with ASD than in controls. The mechanisms underlying cortisol dysregulation in ASD have been explored in rodents. Although rodent models have successfully replicated the major symptoms of autism (i.e., impaired vocal communication, social interaction deficits, and restricted/repetitive patterns of behavior), evidence suggests that the hypothalamic-pituitary-adrenal (HPA) axis system differs between rodents and primates. We developed an ASD model in the common marmoset (Callithrix jacchus), a New World monkey, utilizing prenatal exposure to valproic acid (VPA). In this study, we collected the salivary cortisol levels in VPA-exposed and unexposed marmosets in the morning and afternoon. Our results revealed that both VPA-exposed and unexposed marmosets showed similar diurnal changes in cortisol levels, which were lower in the afternoon than in the morning. However, heightened cortisol levels were observed throughout the day in VPA-exposed marmosets. These results are consistent with those of ASD in humans. Our results suggest that VPA-exposed marmosets show similarities not only in their behavioral patterns and brain pathologies, which we have reported previously, but also in hormonal regulation, validating the usefulness of VPA-exposed marmosets also as a tool for ASD stress research.

Androgens Tend to Be Higher, but What about Altered Progesterone Metabolites in Boys and Girls with Autism?

Background: Evidence exists that steroid hormones are altered in individuals with autism, especially androgens. Despite lower prevalence in girls than boys, evidence of potential alterations in progesterone metabolites is sparse, so the aim of this study was to elucidate different progesterone metabolites in affected children with autism versus healthy controls. Material and Methods: Circadian urine samples from 48 boys and 16 girls with autism spectrum disorders and a matched case−control group were analysed for progesterone metabolites by gas chromatography−mass spectrometry and normalised for creatinine excretion. Results: In boys with autism, the majority of progesterone metabolites were reduced, such as progesterone, 6a-OH-3a5b-TH-progesterone, or 20a-DH-progesterone (p < 0.01 for all). In girls with autism, a similar pattern of reduction in progesterone metabolites was detected; however, potentially due to the relatively small sample, this pattern was only detectable on the level of a trend. Discussion: As stated, androgen levels are higher in boys and girls with autism, but evidence for progesterone metabolites is much sparser. The pattern of a decrease in progesterone metabolites suggests the existence of an altered routing of steroid metabolites, probably in combination with a dysregulation of the HPAG axis. As, recently, increased CYP17A1 activity has been suggested, the stronger routing towards androgens is further implied in line with our findings of lower progesterone concentrations in boys and girls with autism than healthy controls.

Examining the impact of social stressor stimuli in eliciting physiological reactivity in children and adolescents with autism spectrum disorder: a systematic review and meta-analysis protocol

INTRODUCTION

Stress is not experienced the same by everyone. Some individuals, such as individuals with autism spectrum disorder (ASD), are at risk of heightened sensitivity to stress responses. ASD is a neurodevelopmental disorder commonly characterised by deficits in social communication and social interaction. Among different stressor stimuli, social stressors are particularly worth our attention due to the social and communication challenges inherent in ASD. This study aims to systematically evaluate different social stressor stimuli in eliciting physiological reactivity in ASD, focusing on the children and adolescent population.

METHODS AND ANALYSIS

We designed a study protocol for this study and submitted it to PROSPERO for systematic review registration. Any studies with children and adolescents with ASD between the ages of 0 and 18 in clinical and community settings will be included. All types of social stressor interventions will be included. The outcome of interest will include studies with physiological activity of the participants being measured, for example, measures related to autonomic functioning, electrodermal functioning and cortisol level. The primary literature sources will be across four electronic databases: MEDLINE, Embase, PsycInfo and CINAHL in August 2021. The second source of literature will be across grey literature, including ProQuest Dissertations & Theses Global and across clinical trial registries in August 2021. Hand searching of references will be performed on the reference lists of all included studies. Two volunteers pursuing postgraduate-level studies will independently search and screen potential studies for eligibility. Finally, all references considered by hand searching will be reviewed by two researchers. The methodological quality of the research will be assessed by adopting the quality assessment used by a previous study. The assessment consists of four primary categories: descriptive validity, internal validity, external validity and statistical conclusion validity.

ETHICS AND DISSEMINATION

No ethical approval is required for this study. Results will be disseminated through conferences and publications in relevant peer-reviewed journals.

PROSPERO REGISTRATION NUMBER

CRD42021244039.

Can dogs reduce stress levels in school children? effects of dog-assisted interventions on salivary cortisol in children with and without special educational needs using randomized controlled trials

Prolonged or excessive stress negatively affects learning, behavior and health across the lifespan. To alleviate adverse effects of stress in school children, stressors should be reduced, and support and effective interventions provided. Animal-assisted interventions (AAI) have shown beneficial effects on health and wellbeing, however, robust knowledge on stress mediation in children is lacking. Despite this, AAIs are increasingly employed in settings world-wide, including schools, to reduce stress and support learning and wellbeing. This study is the first randomized controlled trial to investigate dog-assisted interventions as a mediator of stress in school children with and without special educational needs (SEN) over the school term. Interventions were carried out individually and in small groups twice a week for 20 minutes over the course of 4 weeks. We compared physiological changes in salivary cortisol in a dog intervention group with a relaxation intervention group and a no treatment control group. We compared cortisol level means before and after the 4 weeks of interventions in all children as well as acute cortisol in mainstream school children. Dog interventions lead to significantly lower stress in children with and without special educational needs compared to their peers in relaxation or no treatment control groups. In neurotypical children, those in the dog interventions showed no baseline stress level increases over the school term. In addition, acute cortisol levels evidenced significant stress reduction following the interventions. In contrast, the no treatment control group showed significant rises in baseline cortisol levels from beginning to end of school term. Increases also occurred in the relaxation intervention group. Children with SEN showed significantly decreased cortisol levels after dog group interventions. No changes occurred in the relaxation or no treatment control groups. These findings provide crucial evidence that dog interventions can successfully attenuate stress levels in school children with important implications for AAI implementation, learning and wellbeing.

The Impact of Emotional Expressions of Parents on their Children with Specific Learning Disorders: The Role of Parental Educational Counseling Program

BACKGROUND: Children are the world’s real treasures; they should be cherished, well raised, and given the chance to develop properly. Some of them in different countries worldwide are suffering from various forms of specific learning disorders (SLDs), which can be extremely frustrating the school child, especially if associated with parental high emotional expression (EE). OBJECTIVES: The purpose of the study is to identify the relation between parents’ EEs and anxiety rate in their children with SLDs and its correlation with serum cortisol level of the children. The effect of parental educational counseling program (PECP) on the anxiety rate of children and parental EE was studied. METHODS: The study was carried out on 140 children with SLD to evaluate their anxiety rate using Taylor anxiety scale of children, and measuring serum cortisol level. Data were collected from parents by EE scale (EES). Taylor anxiety scale and EES were repeated for children and parents after conducting sessions of PECP. RESULTS: Results of Taylor anxiety scale showed that 60% of studied children were suffering from morbid anxiety. Results of EES showed that 80% of parents were practicing high EE. Scores of children on Taylor anxiety scale demonstrated a significant drop from 33.06 ± 10.4 to 25.85 ± 10.4 after applying the intervention (p < 0.001). More than two-thirds of parents became practicing low EE after receiving sessions of the interventional program PECP. Scores of parents on EES showed a significant drop from 61.31 ± 16.84 to 36.51 ± 13.89 after PECP (p < 0.001). A statistically significant positive correlation between scores of Taylor anxiety scale and EES before PECP was found (r = 0.533) and after PECP (r = 0.309). Average level of serum cortisol of children with SLD was 8.973 ± 1.784 mcg/dl, and it was significantly higher in boys than girls (p < 0.05). Serum cortisol level of studied children was higher in children with morbid and severe anxiety (p < 0.001). Cortisol levels of children were significantly higher in those whose parents were practicing high EE. Serum cortisol level of children revealed a positive correlation with each of their scores on Taylor anxiety scale (r = 0.771) and scores of parents on EES (r = 0.468). CONCLUSION: Results of this study proved the presence of direct relation between anxiety in school children with SLDs and high EEs of their parents. Results concluded the effectiveness of PECP in the management of children’s anxiety and parental EE.

Stress System Activation in Children and Adolescents With Autism Spectrum Disorder

The mission of the human stress system is the maintenance of homeostasis in the presence of real or perceived, acute or chronic stressors. The hypothalamic–pituitary–adrenal (HPA) axis and the autonomic nervous system (ANS) are the stress system-related neuroendocrine pathways. There is abundant evidence that children and adolescents with autism spectrum disorder (ASD) may exhibit atypical function within the HPA axis and the ANS both at the resting state and during the presence of social and/or non-social stressors. The aim of this review is to provide an up-to-date summary of the findings regarding stress system alterations in children and adolescents with ASD. We focus on the variations of stress hormones circadian rhythms, specifically cortisol and alpha-amylase (i.e., a surrogate index of epinephrine/norepinephrine secretion), and on the alterations of stress system responsivity to different stressors. Also, we present imaging and immunological findings that have been associated with stress system dysregulation in children and adolescents with ASD. Finally, we review the pivotal role of HPA axis-ANS coordination, the developmental trajectory of the stress system in ASD, and the possible role of early life stress in the dysregulation of the stress system demonstrated in children and adolescents with ASD. This synthesis will hopefully provide researchers with a foundation for an integrated approach to future research into stress system variations in children and adolescents with ASD.

Exposure to GABAA Receptor Antagonist Picrotoxin in Pregnant Mice Causes Autism-Like Behaviors and Aberrant Gene Expression in Offspring

Autism spectrum disorder (ASD) is a neurodevelopmental disorder that is characterized by impairments in social interaction and restricted/repetitive behaviors. The neurotransmitter γ-aminobutyric acid (GABA) through GABA_A receptor signaling in the immature brain plays a key role in the development of neuronal circuits. Excitatory/inhibitory imbalance in the mature brain has been investigated as a pathophysiological mechanism of ASD. However, whether and how disturbances of GABA signaling in embryos that are caused by GABA_A receptor inhibitors cause ASD-like pathophysiology are poorly understood. The present study examined whether exposure to the GABA_A receptor antagonist picrotoxin causes ASD-like pathophysiology in offspring by conducting behavioral tests from the juvenile period to adulthood and performing gene expression analyses in mature mouse brains. Here, we found that male mice that were prenatally exposed to picrotoxin exhibited a reduction of active interaction time in the social interaction test in both adolescence and adulthood. The gene expression analyses showed that picrotoxin-exposed male mice exhibited a significant increase in the gene expression of odorant receptors. Weighted gene co-expression network analysis showed a strong correlation between social interaction and enrichment of the "odorant binding" pathway gene module. Our findings suggest that exposure to a GABA_A receptor inhibitor during the embryonic period induces ASD-like behavior, and impairments in odorant function may contribute to social deficits in offspring.

Self-Regulation Mediates Therapeutic Horseback Riding Social Functioning Outcomes in Youth With Autism Spectrum Disorder

Emerging evidence suggests therapeutic horseback riding improves self-regulation behaviors, social functioning, and language in youth with autism spectrum disorder (ASD). It has been theorized that interacting with horses is calming for youth with ASD, which may influence social and language outcomes. The current study is an exploratory secondary mediation analysis of a previously published randomized controlled trial of therapeutic horseback riding for youth with ASD. We hypothesized that self-regulation would mediate therapeutic horseback riding's effect on social and language outcomes in youth with ASD. Results indicate that self-regulation mediates therapeutic horseback riding's effect on social, but not language outcomes. This paper provides support for the hypothesis that interacting with horses may have a calming effect that serves as a platform for improving social outcomes in youth with autism.

Alteration of peripheral cortisol and autism spectrum disorder: A meta-analysis

Cortisol is the main HPA axis hormone secreted by the adrenal cortex, and influences metabolism, cognition, and behavior. Recently, a plethora of studies have tried to confirm the correlation between peripheral cortisol and autism spectrum disorder (ASD). However, the results were controversial. We assessed the effects of peripheral cortisol on ASD in this study. The included studies were identified according to the inclusion and exclusion criteria. The pooled Hedges' g and its 95% confidence interval were selected to evaluate the association between peripheral cortisol and ASD. Subgroup analyses, sensitivity analyses, meta-regression, and publication bias tests were also undertaken based on the obtained information. There were a total of twelve studies with 375 ASD patients and 335 controls included in our meta-analysis. Obvious heterogeneity across studies was found in the overall analysis. Peripheral cortisol levels were significantly elevated in ASD patients compared with controls in the absence of obvious heterogeneity. A single study did not influence the overall comparison results. Meta-regression analyses revealed that age and gender of the included subjects, sample size, and publication year did not moderate effects on the present results. These findings may provide us some targeted strategies to the diagnosis and treatment of ASD.

CNS pharmacology of NKCC1 inhibitors

The Na-K-2Cl cotransporter NKCC1 and the neuron-specific K-Cl cotransporter KCC2 are considered attractive CNS drug targets because altered neuronal chloride regulation and consequent effects on GABAergic signaling have been implicated in numerous CNS disorders. While KCC2 modulators are not yet clinically available, the loop diuretic bumetanide has been used off-label in attempts to treat brain disorders and as a tool for NKCC1 inhibition in preclinical models. Bumetanide is known to have anticonvulsant and neuroprotective effects under some pathophysiological conditions. However, as shown in several species from neonates to adults (mice, rats, dogs, and by extrapolation in humans), at the low clinical doses of bumetanide approved for diuresis, this drug has negligible access into the CNS, reaching levels that are much lower than what is needed to inhibit NKCC1 in cells within the brain parenchyma. Several drug discovery strategies have been initiated over the last ∼15 years to develop brain-permeant compounds that, ideally, should be selective for NKCC1 to eliminate the diuresis mediated by inhibition of renal NKCC2. The strategies employed to improve the pharmacokinetic and pharmacodynamic properties of NKCC1 blockers include evaluation of other clinically approved loop diuretics; development of lipophilic prodrugs of bumetanide; development of side-chain derivatives of bumetanide; and unbiased high-throughput screening approaches of drug discovery based on large chemical compound libraries. The main outcomes are that (1), non-acidic loop diuretics such as azosemide and torasemide may have advantages as NKCC1 inhibitors vs. bumetanide; (2), bumetanide prodrugs lead to significantly higher brain levels than the parent drug and have lower diuretic activity; (3), the novel bumetanide side-chain derivatives do not exhibit any functionally relevant improvement of CNS accessibility or NKCC1 selectivity vs. bumetanide; (4) novel compounds discovered by high-throughput screening may resolve some of the inherent problems of bumetanide, but as yet this has not been achieved. Thus, further research is needed to optimize the design of brain-permeant NKCC1 inhibitors. In parallel, a major challenge is to identify the mechanisms whereby various NKCC1-expressing cellular targets of these drugs within (e.g., neurons, oligodendrocytes or astrocytes) and outside the brain parenchyma (e.g., the blood-brain barrier, the choroid plexus, and the endocrine system), as well as molecular off-target effects, might contribute to their reported therapeutic and adverse effects.

Homer1a regulates Shank3 expression and underlies behavioral vulnerability to stress in a model of Phelan-McDermid syndrome

Mutations of SHANK3 cause Phelan-McDermid syndrome (PMS), and these individuals can exhibit sensitivity to stress, resulting in behavioral deterioration. Here, we examine the interaction of stress with genotype using a mouse model with face validity to PMS. In Shank3^ΔC/+ mice, swim stress produces an altered transcriptomic response in pyramidal neurons that impacts genes and pathways involved in synaptic function, signaling, and protein turnover. Homer1a, which is part of the Shank3-mGluR-N-methyl-D-aspartate (NMDA) receptor complex, is super-induced and is implicated in the stress response because stress-induced social deficits in Shank3^ΔC/+ mice are mitigated in Shank3^ΔC/+;Homer1a^-/- mice. Several lines of evidence demonstrate that Shank3 expression is regulated by Homer1a in competition with crosslinking forms of Homer, and consistent with this model, Shank3 expression and function that are reduced in Shank3^ΔC/+ mice are rescued in Shank3^ΔC/+;Homer1a^-/- mice. Studies highlight the interaction between stress and genetics and focus attention on activity-dependent changes that may contribute to pathogenesis.

Chemiluminescence analysis of saliva for the assessment of emotional stress in autistic children undergoing a medical examination

Purpose

An electroencephalography (EEG) examination may cause psychological stress in children with autism that can interfere with the examination results. The objective information on the presence or absence of psycho-emotional stress in patients can help interpret electroencephalograms. This paper aimed to demonstrate the potential of noninvasive objective diagnostics of emotional stress in autistic children undergoing an EEG examination based on analysis of saliva.

Design/methodology/approach

This study involved 19 children with autism spectrum disorder (ASD) (ICD-10 F84.0); the mean age was seven years. During EEG examination of the children, behavioral parameters were assessed. The activity of cytochrome P450 reductase (CYPOR) in saliva was measured before and after the EEG procedure using lucigenin-enhanced nicotinamide adenine dinucleotide phosphate-stimulated chemiluminescence assay.

Findings

Significant differences in CYPOR activity were found between the children who were distressed during an EEG examination and the children without behavioral disturbances (Mann–Whitney test, p = 0.002). Thus, the EEG examination resulted in an increase in CYPOR activity in saliva cells, which may prove the stressful effect of this procedure on autistic children.

Originality/value

The chemiluminescent indices reflecting the activity of microsomal CYPOR in cells presenting in saliva correlate with the absence or presence of psychological stress in children; this phenomenon can be explained by an increased metabolism of the stress hormone, cortisol, by the cytochrome P450 microsomal system. Furthermore, the proposed method is completely safe, noninvasive, rapid (recording time is 20 min), inexpensive and promising for an objective assessment of psycho-emotional stress in autistic children undergoing medical examinations.

Potential of Salivary Biomarkers in Autism Research: A Systematic Review

The diagnostic process for autism spectrum disorders (ASD) is based on a behavioral analysis of the suspected individual. Despite intensive research, no specific and valid biomarker has been identified for ASD, but saliva, with its advantages such as non-invasive collection, could serve as a suitable alternative to other body fluids. As a source of nucleic acid of both human and microbial origin, protein and non-protein molecules, saliva offers a complex view on the current state of the organism. Additionally, the use of salivary markers seems to be less complicated not only for ASD screening but also for revealing the etiopathogenesis of ASD, since enrolling neurotypical counterparts willing to participate in studies may be more feasible. The aim of the presented review is to provide an overview of the current research performed on saliva in relation to ASD, mutual complementing, and discrepancies that result in difficulties applying the observed markers in clinical practice. We emphasize the methodological limitations of saliva collection and processing as well as the lack of information regarding ASD diagnosis, which is critically discussed.

An Initial Development and Evaluation of a Culturally Responsive Police Interactions Training for Black Adolescents with Autism Spectrum Disorder

The purpose of the current study was to conduct a qualitative and experimental analysis of a culturally informed police safety skills training for adolescents with autism spectrum disorder (ASD). The current study focused primarily on meeting the unique training needs of Black adolescents with autism spectrum disorder (ASD). A single case design was used to evaluate the initial efficacy and acceptability of a culturally responsive training method. Preliminary evidence about the physiological ramifications of police contact were also collected to begin to examine the broader behavioral and psychophysiological nature of youth's experiences. The current experimental design included in-person simulated contexts that youth, and caregivers, endorsed as relevant to their normal lives, which greatly strengthened the ecological validity of the approach.

Autistic traits and gender modulate emotion changes before and during the COVID-19 pandemic

Individuals with autism spectrum disorder (ASD) show an enhanced response to stressors, and gender plays an important role in stress response. Thus, autistic traits (ATs) in the general population and gender may regulate the emotion changes before and during the COVID-19 pandemic. In the present study, participants were divided into higher and lower ATs groups. The generalized linear models were used to estimate the effects of the independent variables (e.g. the COVID-19 pandemic status (before, during), gender (male, female), and AT groups (higher ATs, lower ATs) and their interactions on emotions measured by the Positive and Negative Affect scales. The results showed that the COVID-19 pandemic reduced positive emotions and increased fear and anger. Furthermore, compared with the status before the COVID-19 pandemic, individuals with higher ATs and females experienced stronger anger and fear than individuals with lower ATs and males during the pandemic. The present study revealed the emotional impacts of the COVID-19 pandemic and greater emotional susceptibility to the pandemic among individuals with higher ATs and females. Our findings provide prospective evidence for understanding the ASD/ATs-related enhanced response to pathogen threat-related stressors and have implications for COVID-19 crisis interventions.

Elevated levels of cortisol, brain-derived neurotropic factor and tissue plasminogen activator in male children with autism spectrum disorder

Several studies demonstrated biological effects of cortisol, brain-derived neurotrophic factor (BDNF) and tissue plasminogen activator (tPA) on human metabolism and central nervous system. Our study investigated the serum levels of tPA along with BDNF and cortisol in children with autism spectrum disorder (ASD). Thirty three male children with ASD ranging in age from 2 to 15 years were selected for the study group and 27 age-matched healthy male children were selected for the control group. The ASD severity was determined by the score on the Autism Behavior Checklist (ABC). The mean cortisol levels for the study group and the control group were 79.1 ± 30.2 ng/ml and 60.0 ± 25.1 ng/ml, respectively. The mean BDNF levels for the study group and the control group were 5.9 ± 2.8 ng/ml and 3.7 ± 1.8 ng/ml, respectively. The mean tPA levels for the study group and the control group were 32.9 ± 18.5 ng/ml and 25.5 ± 15.1 ng/ml, respectively. Cortisol, BDNF and tPA levels were significantly higher in the study group compared to the control group (p < 0.001). There was no statistically significant effect in terms of age, ABC total and subscale scores on serum cortisol, BDNF and tPA levels in the study group (p > 0.05). It may be suggested that elevations may indicate a role in the pathogenesis of ASD or it may be the case that ASD may alter the levels or pathways of these metabolic factors. LAY SUMMARY: The underlying mechanism or a specific metabolic target relevant to autism spectrum disorder (ASD) has not yet been identified. Cortisol, brain-derived neurotrophic factor (BDNF) and tissue plasminogen activator (tPA) have biological effects on neuroplasticity but little is known about the role of cortisol and tPA-BDNF pathway in ASD. In the present study focused on male children with ASD, we have found higher blood levels of cortisol, BDNF and tPA than their healthy peers. This is the first clinical study to evaluate the serum tPA levels along with BDNF and cortisol in ASD. The results suggest that several neurotrophic and other related markers should be born in mind while examining children with ASD.

Engrailed 2 deficiency and chronic stress alter avoidance and motivation behaviors

Autism spectrum disorder (ASD) is a pervasive neurodevelopmental disorder characterized by impairments in social interaction, cognition, and communication, as well as the presence of repetitive or stereotyped behaviors and interests. ASD is most often studied as a neurodevelopmental disease, but it is a lifelong disorder. Adults with ASD experience more stressful life events and greater perceived stress, and frequently have comorbid mood disorders such as anxiety and depression. It remains unclear whether adult exposure to chronic stress can exacerbate the behavioral and neurodevelopmental phenotypes associated with ASD. To address this issue, we first investigated whether adult male and female Engrailed-2 deficient (En2-KO, En2-/-) mice, which display behavioral disturbances in avoidance tasks and dysregulated monoaminergic neurotransmitter levels, also display impairments in instrumental behaviors associated with motivation, such as the progressive ratio task. We then exposed adult En2-KO mice to chronic environmental stress (CSDS, chronic social defeat stress), to determine if stress exacerbated the behavioral and neuroanatomical effects of En2 deletion. En2-/- mice showed impaired instrumental acquisition and significantly lower breakpoints in a progressive ratio test, demonstrating En2 deficiency decreases motivation to exert effort for reward. Furthermore, adult CSDS exposure increased avoidance behaviors in En2-KO mice. Interestingly, adult CSDS exposure also exacerbated the deleterious effects of En2 deficiency on forebrain-projecting monoaminergic fibers. Our findings thus suggest that adult exposure to stress may exacerbate behavioral and neuroanatomical phenotypes associated with developmental effects of genetic En2 deficiency.

Altered hypothalamic DNA methylation and stress-induced hyperactivity following early life stress

Exposure to early life stress (ELS) during childhood or prenatally increases the risk of future psychiatric disorders. The effect of stress exposure during the neonatal period is less well understood. In preterm infants, exposure to invasive procedures is associated with altered brain development and future stress responses suggesting that the neonatal period could be a key time for the programming of mental health. Previous studies suggest that ELS affects the hypothalamic epigenome, making it a good candidate to mediate these effects. In this study, we used a mouse model of early life stress (modified maternal separation; MMS). We hypothesised MMS would affect the hypothalamic transcriptome and DNA methylome, and impact on adult behaviour. MMS involved repeated stimulation of pups for 1.5 h/day, whilst separated from their mother, from postnatal day (P) 4-6. 3'mRNA sequencing and DNA methylation immunoprecipitation (meDIP) sequencing were performed on hypothalamic tissue at P6. Behaviour was assessed with the elevated plus, open field mazes and in-cage monitoring at 3-4 months of age. MMS was only associated with subtle changes in gene expression, but there were widespread alterations in DNA methylation. Notably, differentially methylated regions were enriched for synapse-associated loci. MMS resulted in hyperactivity in the elevated plus and open field mazes, but in-cage monitoring revealed that this was not representative of habitual hyperactivity. ELS has marked effects on DNA methylation in the hypothalamus in early life and results in stress-specific hyperactivity in young adulthood. These results have implications for the understanding of ELS-mediated effects on brain development.

Human Self-Domestication and the Evolution of Pragmatics

As proposed for the emergence of modern languages, we argue that modern uses of languages (pragmatics) also evolved gradually in our species under the effects of human self-domestication, with three key aspects involved in a complex feedback loop: (a) a reduction in reactive aggression, (b) the sophistication of language structure (with emerging grammars initially facilitating the transition from physical aggression to verbal aggression); and (c) the potentiation of pragmatic principles governing conversation, including, but not limited to, turn-taking and inferential abilities. Our core hypothesis is that the reduction in reactive aggression, one of the key factors in self-domestication processes, enabled us to fully exploit our cognitive and interactional potential as applied to linguistic exchanges, and ultimately to evolve a specific form of communication governed by persuasive reciprocity-a trait of human conversation characterized by both competition and cooperation. In turn, both early crude forms of language, well suited for verbal aggression/insult, and later more sophisticated forms of language, well suited for persuasive reciprocity, significantly contributed to the resolution and reduction of (physical) aggression, thus having a return effect on the self-domestication processes. Supporting evidence for our proposal, as well as grounds for further testing, comes mainly from the consideration of cognitive disorders, which typically simultaneously present abnormal features of self-domestication (including aggressive behavior) and problems with pragmatics and social functioning. While various approaches to language evolution typically reduce it to a single factor, our approach considers language evolution as a multifactorial process, with each player acting upon the other, engaging in an intense mutually reinforcing feedback loop. Moreover, we see language evolution as a gradual process, continuous with the pre-linguistic cognitive abilities, which were engaged in a positive feedback loop with linguistic innovations, and where gene-culture co-evolution and cultural niche construction were the main driving forces.

Disruption of circadian rhythm and risk of autism spectrum disorder: role of immune-inflammatory, oxidative stress, metabolic and neurotransmitter pathways

Circadian rhythms in most living organisms are regulated by light and synchronized to an endogenous biological clock. The circadian clock machinery is also critically involved in regulating and fine-tuning neurodevelopmental processes. Circadian disruption during embryonic development can impair crucial phases of neurodevelopment. This can contribute to neurodevelopmental disorders like autism spectrum disorder (ASD) in the offspring. Increasing evidence from studies showing abnormalities in sleep and melatonin as well as genetic and epigenetic changes in the core elements of the circadian pathway indicate a pivotal role of circadian disruption in ASD. However, the underlying mechanistic basis through which the circadian pathways influence the risk and progression of ASD are yet to be fully discerned. Well-recognized mechanistic pathways in ASD include altered immune-inflammatory, nitro oxidative stress, neurotransmission and synaptic plasticity, and metabolic pathways. Notably, all these pathways are under the control of the circadian clock. It is thus likely that a disrupted circadian clock will affect the functioning of these pathways. Herein, we highlight the possible mechanisms through which aberrations in the circadian clock might affect immune-inflammatory, nitro-oxidative, metabolic pathways, and neurotransmission, thereby driving the neurobiological sequelae leading to ASD.

Biological Timing and Neurodevelopmental Disorders: A Role for Circadian Dysfunction in Autism Spectrum Disorders

Autism spectrum disorders (ASDs) are a spectrum of neurodevelopmental disorders characterized by impaired social interaction and communication, as well as stereotyped and repetitive behaviors. ASDs affect nearly 2% of the United States child population and the worldwide prevalence has dramatically increased in recent years. The etiology is not clear but ASD is thought to be caused by a combination of intrinsic and extrinsic factors. Circadian rhythms are the ∼24 h rhythms driven by the endogenous biological clock, and they are found in a variety of physiological processes. Growing evidence from basic and clinical studies suggest that the dysfunction of the circadian timing system may be associated with ASD and its pathogenesis. Here we review the findings that link circadian dysfunctions to ASD in both experimental and clinical studies. We first introduce the organization of the circadian system and ASD. Next, we review physiological indicators of circadian rhythms that are found disrupted in ASD individuals, including sleep-wake cycles, melatonin, cortisol, and serotonin. Finally, we review evidence in epidemiology, human genetics, and biochemistry that indicates underlying associations between circadian regulation and the pathogenesis of ASD. In conclusion, we propose that understanding the functional importance of the circadian clock in normal and aberrant neurodevelopmental processes may provide a novel perspective to tackle ASD, and clinical treatments for ASD individuals should comprise an integrative approach considering the dynamics of daily rhythms in physical, mental, and social processes.

Developmental effects in physiological stress in early adolescents with and without autism spectrum disorder

INTRODUCTION

Humans place high value on how they are socially evaluated by others. The Trier Social Stress Test (TSST) is a well-established measure of social evaluative threat that promotes activation of the hypothalamic pituitary adrenal (HPA) axis and release of cortisol. Higher cortisol responses in typically developing (TD) adolescents are influenced by age and pubertal development especially in later stages. Children with ASD have been shown to exhibit blunted cortisol in response to the TSST although adults with ASD show a more prototypical response. The current study examined physiological stress in early adolescents with ASD and TD. It was hypothesized that TD youth would show elevated cortisol in response to the TSST influenced by age and pubertal stage. In contrast, youth with ASD would show a more diminished stress response yet still show effects for age and pubertal development METHODS: The sample included 241 youth, 138 with ASD (median age=11.25) and 103 TD (median age=11.67). Standardized diagnostic and pubertal development (genital/breast (GB), and pubic hair (PH) stage) physical exams were performed. Salivary cortisol was collected before and after the TSST. Linear mixed effects models examined the effects of baseline cortisol, time, age, sex, pubertal stage, and diagnosis.

RESULTS

We did not find an effect of early pubertal development stage (GB or PH) on cortisol response. There was an interaction between age and TSST timepoint, showing stronger effects for older children across the timeline especially during the stressor. Finally, there was a significant diagnosis by TSST timepoint interaction characterized by a blunted cortisol stress response in youth with ASD compared to TD participants who showed higher cortisol.

DISCUSSION

We found evidence that age contributes to an increase in cortisol in response to social evaluative threat during early adolescence. TD youth exhibit an adaptive elevated stress response to psychosocial threat whereas youth with ASD do not. There may exist a developmental lag in the perception of and stress responsivity to social evaluation which may emerge in older adolescents with ASD.

Salivary cortisol and alpha-amylase daily profiles and stress responses to an academic performance test and a moral cognition task in children with neurodevelopmental disorders

There is evidence that children with neurodevelopmental disorders may exhibit atypical responses to stress and alterations in concentrations and diurnal secretion of stress hormones. We assessed diurnal profiles and stress responses of salivary cortisol and alpha-amylase (sAA) in children with attention-deficit hyperactivity disorder (ADHD), autism spectrum disorder (ASD) and specific learning disorder (SLD) compared to typically developing children (TD). A total of 157 children of both sexes, aged between 6 and 12 years old, took part in the study distributed into four groups: ADHD (N = 34), ASD (N = 56), SLD (N = 43) and TD (N = 24). Salivary samples were collected at three time points during a day, as well as before and 5 min after an academic performance test and a moral cognition task. ADHD children had lower evening and diurnal sAA levels, adjusted for age. Also, ASD children showed lower diurnal sAA secretion, adjusted for age. The mean percentage change for salivary cortisol and sAA after both tests did not differ between the groups. In conclusion, we demonstrated alterations in diurnal autonomic functioning in children with ADHD and ASD, while hypothalamic-pituitary-adrenal axis functioning did not differ between the clinical and the comparison groups.

Evidence for decreased parasympathetic response to a novel peer interaction in older children with autism spectrum disorder: a case-control study

Background

Individuals with autism spectrum disorder (ASD) often experience elevated stress during social interactions and may have difficulty forming and maintaining peer relationships. The autonomic nervous system (ANS) directs physiological changes in the body in response to a number of environmental stimuli, including social encounters. Evidence suggests the flexibility of the ANS response is an important driving factor in shaping social behavior. For youth with ASD, increased stress response and/or atypical ANS regulation to benign social encounters may therefore influence social behaviors, and, along with developmental and experiential factors, shape psychological outcomes.

Methods

The current study measured ANS response to a peer-based social interaction paradigm in 50 typically developing (TD) children and 50 children with ASD (ages 10–13). Respiratory sinus arrhythmia (RSA), a cardiac measure of parasympathetic influence on the heart, and pre-ejection period (PEP), a sympathetic indicator, were collected. Participants engaged in a friendly, face-to-face conversation with a novel, same-aged peer, and physiological data were collected continuously before and during the interaction. Participants also reported on state anxiety following the interaction, while parents reported on the child’s social functioning and number of social difficulties.

Results

Linear mixed models revealed that, while there were no diagnostic effects for RSA or PEP, older youth with ASD appeared to demonstrate a blunted parasympathetic (RSA) response. Further, increased severity of parent-reported social symptoms was associated with lower RSA. Youth with ASD reported more anxiety following the interaction; however, symptoms were not related to RSA or PEP response based on linear mixed modeling.

Conclusions

Physiological regulation, age, and social functioning likely influence stress responses to peer interactions for youth with ASD. Parasympathetic functioning, as opposed to sympathetic arousal, may be especially important in behavioral regulation, as older youth with ASD demonstrated atypical regulation and response to the social interaction paradigm. Future studies should help to further elucidate the developmental factors contributing to stress responses in ASD, the impact of physiological response on observable social behavior, and potential long-term consequences of chronic social stress in youth with ASD.

Supplementary Information

The online version contains supplementary material available at 10.1186/s11689-020-09354-x.

Relationship Between Parental Attachment and Stress Elevation and Synchrony in Pediatric Occupational Therapy Patient-Parent Dyads

IMPORTANCE

Populations already experiencing chronic stress, such as families with children who are neurologically atypical, are at particular risk for developing stress-related disease.

OBJECTIVE

To establish feasibility of collecting salivary samples from pediatric occupational therapy patients and their parents in a clinical setting and at home and to examine associations among parental attachment style, parent self-reported stress, and physiological stress (i.e., cortisol) in pediatric occupational therapy patients who were neurologically atypical and their parents (N = 10 dyads).

DESIGN

Cross-sectional pilot study to test feasibility.

SETTING

Sliding-scale university clinic.

PARTICIPANTS

Participants were 10 children undergoing occupational therapy treatment and their parent. Families were approached and told the study was voluntary and would not affect their treatment. Families provided informed consent.

OUTCOMES AND MEASURES

Parents completed measures to assess their own attachment style, general and parenting stress, and stress in their child. Children and parents provided saliva samples during an occupational therapy clinic visit and collected samples at home to measure cortisol level.

RESULTS

Parent attachment avoidance was related to increased parent cortisol levels in the clinic and increased child cortisol levels at home. Parent and child cortisol levels had a strong, positive relationship in the clinic but not at home. We did not observe a difference between cortisol levels in children or parents in the clinic or at home.

CONCLUSIONS AND RELEVANCE

We concluded that this protocol is feasible and provide suggestions for future research.

WHAT THIS ARTICLE ADDS

Stress physiology in pediatric occupational therapy clients should be considered within the context of the family system. Family-based interventions may be particularly helpful for reducing client stress in this population.

The Prenatal Hormone Milieu in Autism Spectrum Disorder

Though the etiology of autism spectrum disorder (ASD) remains largely unknown, recent findings suggest that hormone dysregulation within the prenatal environment, in conjunction with genetic factors, may alter fetal neurodevelopment. Early emphasis has been placed on the potential role of in utero exposure to androgens, particularly testosterone, to theorize ASD as the manifestation of an "extreme male brain." The relationship between autism risk and obstetric conditions associated with inflammation and steroid dysregulation merits a much broader understanding of the in utero steroid environment and its potential influence on fetal neuroendocrine development. The exploration of hormone dysregulation in the prenatal environment and ASD development builds upon prior research publishing associations with obstetric conditions and ASD risk. The insight gained may be applied to the development of chronic adult metabolic diseases that share prenatal risk factors with ASD. Future research directions will also be discussed.

The Generalized Adaptation Account of Autism

The heterogeneous phenomenology of autism together with diverse patterns of comorbidities led in the past to formulation of manifold theories and hypotheses on different explanatory levels. We scrutinize most recent findings from genetics, neurobiology and physiology and derive testable hypotheses about possible physiological links between domains. With focus on altered sensory perception and neuronal processing in ASD, we assume two intertwined regulatory feedback circuits under the umbrella of genetics and environmental factors. Both regulatory circuits are highly variable between individuals in line with the heterogeneous spectrum of ASD. The circuits set off from altered pathways and connectivity in ASD, fueling HPA-axis activity and distress. In the first circuit altered tryptophan metabolism leads to higher neurotoxic substances and reinforces the excitation:inhibition imbalance in the brain. The second circuit focuses on the impact and interaction with the environment and its rhythms in ASD. With lower melatonin levels, as the pacemaker molecule of the circadian system, we assume misalignment to outer and inner states corroborated from the known comorbidities in ASD. Alterations of the microbiome composition in ASD are supposed to act as a regulatory linking factor for both circuits. Overall, we assume that altered internal balance on cellular and neurophysiological levels is one of the main reasons leading to a lower ability in ASD to adapt to the environment and own internal changing states, leading to the conceptualization of autism as a condition of generalized imbalance in adaptation. This comprehensive framework opens up new perspectives on possible intervention and prevention strategies.

Endocrinological Abnormalities in Autism

A number of chemical messengers, such as various hormones and hormone-like substances, along with neurotransmitters, such as serotonin, dopamine, and norepinephrine, are directly or indirectly linked with the encoding of social behavior via their action at the amygdala, hippocampus, and other related brain structures known to be involved in different aspects of social development. It is thought that any imbalance in the secretion and action of these chemicals may lead to defective or abnormal social behaviors that are the hallmarks of Autism Spectrum Disorders (ASDs). Many of the studies have described an association between ASDs and endocrine dysfunction, but have failed to establish a cause-effect connection between these 2 conditions. All together, the literature regarding the role of endocrine-related factors and ASDs is sparse and remains somewhat preliminary, controversial, and inconclusive. Thus, more research is needed in the future to shed more light on this topic.

Endocrine Insights into the Pathophysiology of Autism Spectrum Disorder

Autism spectrum disorder (ASD) is a class of neurodevelopmental disorders that affects males more frequently than females. Numerous genetic and environmental risk factors have been suggested to contribute to the development of ASD. However, no one factor can adequately explain either the frequency of the disorder or the male bias in its prevalence. Gonadal, thyroid, and glucocorticoid hormones all contribute to normal development of the brain, hence perturbations in either their patterns of secretion or their actions may constitute risk factors for ASD. Environmental factors may contribute to ASD etiology by influencing the development of neuroendocrine and neuroimmune systems during early life. Emerging evidence suggests that the placenta may be particularly important as a mediator of the actions of environmental and endocrine risk factors on the developing brain, with the male being particularly sensitive to these effects. Understanding how various risk factors integrate to influence neural development may facilitate a clearer understanding of the etiology of ASD.

Autism and Williams syndrome: truly mirror conditions in the socio-cognitive domain?

Autism Spectrum Disorders (ASD) and Williams Syndrome (WS) are frequently characterized as mirror conditions in the socio-cognitive domain, with ASD entailing restrictive social interests and with WS exhibiting hypersociability. In this review paper, we examine in detail the strong points and deficits of people with ASD or WS in the socio-cognitive domain and show that both conditions also share some common features. Moreover, we explore the neurobiological basis of the social profile of ASD and WS and found a similar mixture of common affected areas and condition-specific impaired regions. We discuss these findings under the hypothesis of a continuum of the socio-cognitive abilities in humans.

Catatonia as a presentation of autism in a child: a case report

Catatonia commonly refers to a cluster of movement abnormalities, behaviour, volition and speech that has long been associated with psychiatric disorders in adults. Recent evidence suggests increasing prevalence in adolescents and older children with autistic spectrum disorder (ASD), but its occurrence in younger children is rare. Here we describe a 6-year-old boy presenting with catatonic autism, highlighting the diagnostic challenge and demonstrating the importance of timely assessment and management.