Co-occurring trajectories of anxiety and insistence on sameness behaviour in autism spectrum disorder

Longitudinal Analyses of Mental Health in Autistic Individuals: A Systematic Review

BACKGROUND/OBJECTIVES

Co-occurring mental health conditions affect autistic individuals at high rates, impacting their well-being and quality of life. Mental health conditions are often appropriate treatment targets that can improve the lives of autistic individuals. Because of this, there is growing interest in predictors of mental health and behavioral outcomes. Given the rapidly evolving evidence base and growing literature using longitudinal cohorts, it is unclear which predictors of symptoms of anxiety and depression are consistent, and which are not. Additionally, it is difficult to deduce which predictors of mental health symptoms at a given time also predict change over time. This can be partially due to the different statistical approaches that are implemented, including trajectory vs. non-trajectory methodologies.

METHODS

We conducted a systematic review to evaluate how non-trajectory and trajectory analyses inform our knowledge of how symptoms of anxiety and depression change over time. Additionally, we aimed to identify important predictors of change and later anxiety and depressive symptoms in autistic individuals.

RESULTS

There is variability in symptoms of anxiety and depression in autistic individuals. Adaptive skills arose as significant predictors of change and of later symptoms of both anxiety and depression. Peer relationships in school age seem to be particularly important in predicting later symptoms of depression.

CONCLUSIONS

This review provides evidence that there are different trajectories and different patterns of mental health symptoms over the lifespan, providing further evidence that autism is a developmental condition that changes over time in different ways for different people. Implications and future directions are further discussed.

Prevention and Reduction of Anxiety in Autistic Preschoolers Through an Autism-Specific Parent-Mediated Intervention: A Pilot Randomised Controlled Trial Evaluating Short and Longer Term Outcomes

Anxiety is a common co-occurring condition for autistic preschoolers. Whilst there has been extensive research evaluating anxiety prevention/reduction interventions for neurotypical preschoolers, such research is limited for autistic children. Fifty-seven parents of autistic 4-5-year olds, with varying levels of anxiety, participated in a randomised controlled trial of an autism-specific, parent-mediated intervention (CLK-CUES) to prevent or reduce anxiety in autistic preschoolers. Baseline, short-term (post-intervention) and longer term (12 months follow-up) assessments included child anxiety (ASC-ASD-P and PAS-R), intolerance of uncertainty, and parent well-being. (Trial registration ACTRN12620001322921). There were no reports of harmful effects of the intervention or trial. Linear mixed models show a significant group x time interaction for ASC-ASD-P Total score and the Uncertainty subscale with medium and large effect sizes. Post-hoc analyses show a significant decline for only the intervention group in anxiety (specifically, anxiety around uncertainty) from pre-post intervention, maintained at one year follow-up. There was no change on the PAS-R or other ASC-ASD-P subscales. CLK-CUES shows promise as a way to prevent and reduce anxiety in young autistic children, specifically anxiety related to uncertainty. Trials with larger samples are warranted. Findings also highlight the importance of using measures designed for autistic children.

Characterising Insistence on Sameness and Circumscribed Interests: A Qualitative Study of Parent Perspectives

Manifestations of insistence on sameness (IS) and circumscribed interests (CI) are complex, with individuals varying considerably, not only in the types of behaviours they express, but also in terms of a behaviour's frequency, intensity, trajectory, adaptive benefits, and impacts. However, current quantitative RRB instruments capture only certain aspects of these behaviours (e.g., mostly frequency or general "severity"). Thus, the current study utilised a semi-structured caregiver interview to provide an in-depth, qualitative characterization of different aspects of IS and CI presentation. Caregivers of 27 autistic children and adolescents displaying IS and/or CI behaviours (3-16 years; 18 males; 9 females) participated in a semi-structured interview. Responses were analysed using thematic framework analysis. Framework analysis identified nine different aspects of IS and CI presentation: (1) intensity, (2) frequency, (3) emergence of behaviour, (4) changes over time, (5) day-to-day fluctuations, (6) purpose/adaptive benefit, (7) experiences of distress, (8) challenges for the individual, their family, and their socialisation, and (9) management strategies and their effectiveness. Autistic children and adolescents were reported to vary greatly on each of these dimensions. Findings demonstrate the complexity of IS and CI presentations and highlight the need for more comprehensive quantitative assessments that independently assess the frequency, intensity, and impact of behaviours. Further, findings reported here emphasize the need for ecologically valid measures that assess the contexts in which these behaviours occur and how their presentations can change within and across days.

Metabolic network analysis of pre-ASD newborns and 5-year-old children with autism spectrum disorder

Classical metabolomic and new metabolic network methods were used to study the developmental features of autism spectrum disorder (ASD) in newborns (n = 205) and 5-year-old children (n = 53). Eighty percent of the metabolic impact in ASD was caused by 14 shared biochemical pathways that led to decreased anti-inflammatory and antioxidant defenses, and to increased physiologic stress molecules like lactate, glycerol, cholesterol, and ceramides. CIRCOS plots and a new metabolic network parameter,V ° net, revealed differences in both the kind and degree of network connectivity. Of 50 biochemical pathways and 450 polar and lipid metabolites examined, the developmental regulation of the purine network was most changed. Purine network hub analysis revealed a 17-fold reversal in typically developing children. This purine network reversal did not occur in ASD. These results revealed previously unknown metabolic phenotypes, identified new developmental states of the metabolic correlation network, and underscored the role of mitochondrial functional changes, purine metabolism, and purinergic signaling in autism spectrum disorder.

Examining the Relationship Between Anxiety Severity and Autism-Related Challenges During Cognitive Behavioral Therapy for Children with Autism

PURPOSE

Using data from a randomized clinical trial evaluating cognitive behavioral therapy (CBT) for children with autism and co-occurring anxiety, this study examined the relationship between autism features and anxiety symptoms throughout CBT.

METHODS

Two multilevel mediation analyses were run which examined the mediating role of changes in anxiety for changes in two core features of autism, (a) repetitive and restrictive behaviors (RRBs) and (b) social communication/interaction impairments, between pre- and post-treatment.

RESULTS

Indirect effects between time and autism characteristics were significant for both models, indicating that as anxiety changes, so do RRBs and social communication/interaction as the outcomes respectively.

CONCLUSION

Findings suggest a bidirectional relationship between anxiety and autism features. Implications of these findings are discussed.

Emotion regulation and emotion dysregulation in children and adolescents with Autism Spectrum Disorder: A meta-analysis of evaluation and intervention studies

Children and adolescents with Autism Spectrum Disorder (ASD) often experience challenges in emotion regulation (ER) and emotion dysregulation (ED) which can interfere with their adaptive functioning. This study aimed to systematically review and meta-analyze the evidence on ER/ED in children and/or adolescents with ASD, examining its relationship with the following variables: internalizing and externalizing symptoms, cognitive function and social skills, and the effectiveness of non-pharmacological interventions addressing ER difficulties. Both electronic and manual searches were conducted to identify potential studies. Fifty-five studies were included in the meta-analysis. A statistically significant between-group difference was found, suggesting greater ER/ED challenges in the ASD group. Also, the ASD group showed more maladaptive ER strategies and fewer adaptive ER strategies compared to the non-ASD participants. Additionally, more severe ASD and poorer social skills were associated with greater ED and poorer ER skills, respectivelly. Furthermore, there was a significant correlation between internalizing symptomatology and both adaptive and maladaptive ER strategies. Studies of non-pharmacological interventions showed significant improvement in both ER and ED. These results imply that assessing ER/ED in children and adolescents with ASD should be part of the evaluation process, and it should also be a focal point for intervention in this population.

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.

Characterizing subdomains of insistence on sameness in autistic youth

Insistence on sameness (IS) encompasses a range of behavioral patterns, including resistance to change, routines, and ritualized behaviors, that can be present across social and non-social contexts. Given the breadth of behaviors encompassed by IS, it is important to determine whether this domain is best conceptualized and measured as uni- or a multi-dimensional construct. Therefore, the current study aimed to characterize the structure of IS and explore potentially distinct of patterns of associations between identified IS factors and relevant correlates, including age, sex, IQ, anxiety, social abilities, emotional and behavioral dysregulation, and sensory hypersensitivity. Exploratory graph analysis was conducted using the dimensional assessment of restricted and repetitive behaviors to examine the structure of IS in a sample 1892 autistic youth (Mage  = 10.82, SDage  = 4.14; range: 3-18 years; 420 females) recruited from the Simons Foundation Powering Autism Research for Knowledge cohort. Three distinct IS subdomains labeled as IS-Ritualistic/sameness, IS-Routines, and IS-Others (referring to IS behaviors during interactions with others) were identified. Generalized additive models demonstrated that each of the IS subdomains showed a unique pattern of association with key variables. More specifically, while sensory hypersensitivity was significantly associated with IS-Ritualistic/sameness and IS-Routines, it was not associated with IS-Others. Further, while emotional dysregulation was a unique predictor of IS-Ritualistic/sameness (but not IS-Routines or IS-Others), social interaction abilities were a unique predictor of IS-Routines (but not IS-Ritualistic/sameness or IS-Others). Current findings provide preliminary evidence that the IS may encompass several distinct subdomains.

Developmental cascades between insistence on sameness behaviour and anxiety symptoms in autism spectrum disorder

Autistic children experience high rates of anxiety. Insistence on sameness behaviour (IS) is a core feature of autism that appears correlated with anxiety severity. The objective of this study was to examine the longitudinal relations between anxiety and IS in autistic children using a developmental cascade model. A longitudinal cohort of 421 autistic children was followed between 4 and 11 years of age. Anxiety was quantified using items from the Anxiety Problems subscale of the Child Behavior Checklist; sameness behaviours were measured using the Repetitive Behavior Scale-Revised, Ritualistic/sameness subscale (both parent-report measures). Structural equation modelling was used to examine the longitudinal and directional associations between anxiety and IS at four time-points, through cross-lagged panel models (CLPM) with and without a random-intercepts component (RI-CLPM). Both the CLPM and the RI-CLPM had good fit. Significant directional associations were detected whereby elevated or increasing IS preceded elevated or increasing anxiety symptoms 1-2 years later, respectively. Stable baseline tendencies towards anxiety and IS as between-person traits (intercepts) were strongly associated (standardized estimate = 0.69, p < 0.001). The magnitude of the cross-sectional associations between anxiety and IS appeared to lessen with age. IS and anxiety symptoms in autism are closely related. They appear to be shared traits that mirror each other particularly in younger children. Increasing IS may be a sign of emerging future anxiety. Interventions that target IS to reduce or prevent anxiety amongst school-aged autistic children merit further study.

Understanding the prevalence and manifestation of anxiety and other socio-emotional and behavioural difficulties in children with Developmental Language Disorder

BACKGROUND

It is well-documented that children with Developmental Language Disorder (DLD) have a higher likelihood of experiencing anxiety, as well as other socio-emotional and behavioural (SEB) difficulties. Despite this, there is little consensus as to how these difficulties manifest. This study aims to understand the prevalence of broader SEB difficulties and anxiety, informing intervention development by understanding the relationships between them.

METHODS

A mixed-methods, case-control study was conducted. First, an online survey was completed by 107 parents of either children with DLD ("DLD sample"; n = 57) or typically developing children ("typical sample"; n = 50), aged 6-12 years old. Binary SEB statements informed by previous qualitative work (e.g. "my child requires routine/sameness"; "my child has frequent tantrums") provided an insight into the prevalence of SEB difficulties in both DLD and typical samples. Validated measures of anxiety, emotion regulation, intolerance of uncertainty, insistence on sameness, family stress and coping mechanisms were also collected. Correlation and mediation analyses were run using these validated measures to understand the manifestation of anxiety in children with DLD in more detail. Qualitative interviews were then carried out with a select panel of survey respondents (n = 4).

RESULTS

The DLD sample scored significantly higher on all binary SEB statements than the typical sample: experiencing anxiety (80.7%, p < .05), requiring routine and sameness (75.4%, p < .001) and emotional dysregulation (75.4%; p < .001) were the most common difficulties reported for children with DLD. Using the validated scales, family stress and coping mechanisms were found to only correlate with the manifestation of anxiety in the typical group, not the DLD group. "Intolerance of uncertainty" and "insistence on sameness" were found to fully mediate the relationship between DLD diagnosis and symptoms of anxiety. Parent's interviews provided contextual support for the analysis, as well as highlighting sensory sensitivities as a focus for future research.

CONCLUSIONS

Parents of children with DLD appear to cope well with their children's complex SEB needs. Intervention focussing on intolerance of uncertainty may help the management of difficulties with anxiety. Behaviours such as insistence on sameness should be investigated further, as potential indicators for anxiety amongst children with DLD.

Divergent projections of the prelimbic cortex mediate autism- and anxiety-like behaviors

The comorbidity of autism spectrum disorder and anxiety is common, but the underlying circuitry is poorly understood. Here, Tmem74-/- mice showed autism- and anxiety-like behaviors along with increased excitability of pyramidal neurons (PNs) in the prelimbic cortex (PL), which were reversed by Tmem74 re-expression and chemogenetic inhibition in PNs of the PL. To determine the underlying circuitry, we performed conditional deletion of Tmem74 in the PNs of PL of mice, and we found that alterations in the PL projections to fast-spiking interneurons (FSIs) in the dorsal striatum (dSTR) (PLPNs-dSTRFSIs) mediated the hyperexcitability of FSIs and autism-like behaviors and that alterations in the PL projections to the PNs of the basolateral amygdaloid nucleus (BLA) (PLPNs-BLAPNs) mediated the hyperexcitability of PNs and anxiety-like behaviors. However, the two populations of PNs in the PL had different spatial locations, optogenetic manipulations revealed that alterations in the activity in the PL-dSTR or PL-BLA circuits led to autism- or anxiety-like behaviors, respectively. Collectively, these findings highlight that the hyperactivity of the two populations of PNs in the PL mediates autism and anxiety comorbidity through the PL-dSTR and PL-BLA circuits, which may lead to the development of new therapeutics for the autism and anxiety comorbidity.

Repetitive and restricted behaviors and interests in autism spectrum disorder: relation to individual characteristics and mental health problems

BACKGROUND

Although repetitive and restricted behaviors and interests (RRBIs) may interfere with well-being and functioning in autistic individuals, research on their relation to sex, age, cognitive level, and mental health problems remains unclear. Much of the research to date has used broad categorizations rather than specific categorizations of RRBIs to examine the difference in RRBIs between individuals. The purpose of this study was to explore, in different groups of individuals, the presence of specific RRBI subtypes, and to examine the association of specific RRBI subtypes with symptoms of internalizing and externalizing behaviors.

METHODS

Secondary data analyses were conducted using the Simons Simplex Collection dataset, which included 2,758 participants (aged 4 to 18). Families of autistic children completed the Repetitive Behavior Scale-Revised (RBS-R) and the Child Behavior Checklist.

RESULTS

Across all RBS-R subtypes, results revealed no sex differences. Older children showed higher rates of Ritualistic/Sameness behaviors than younger children and adolescents, whereas younger and older children showed more Stereotypy than adolescents. Additionally, lower cognitive level groups showed higher rates of RBS-R subtypes except for Ritualistic/Sameness. After controlling for age and cognitive level, RBS-R subtypes accounted for a substantial amount of variance in internalizing and externalizing behaviors (23% and 25%, respectively). Specifically, Ritualistic/Sameness and Self-Injurious Behavior both predicted internalizing and externalizing behaviors, whereas Stereotypy only predicted internalizing behavior.

CONCLUSIONS

These findings have key clinical implications that emphasize not only the consideration of sex, age, and cognitive level, but also specific RRBIs and co-occurring mental health problems, when assessing for ASD and designing individualized interventions.

Sex differences in the course of autistic and co-occurring psychopathological symptoms in adolescents with and without autism spectrum disorder

LAY ABSTRACT

There is an ongoing debate as to whether autism spectrum disorder (ASD) is expressed differently in women than men. Studies on sex differences in autistic symptoms and symptoms of other psychiatric problems present in individuals with autism generally do not include a general population comparison group, making it unclear whether differences are specific to autism or merely reflecting development in the general population. In this study, we compared sex differences in the course of autistic and at the same time present symptoms of other psychiatric problems in adolescents with milder forms of ASD to those in a group of the general population with an equal intelligence quotient (IQ) and socioeconomic status. Data of five assessment moments from ages 11 to 22 years were analyzed using a statistic procedure that allowed us to determine which factors affect the course of symptoms over time. We found that in adolescence, sex differences in the course of psychopathological symptoms specific for autism are confined to the repetitive stereotyped domains. Males had higher scores on the sensory/stereotypic and resistance to change domains, the latter difference disappeared during the course of adolescence due to an increase of these problems in autistic females. Other sex differences, among which an increase over time in mood and anxiety problems in females was the most outstanding, were also observed in females without autism. These sex-specific differences have relevance in the clinical care of autistic men and women, although they are subtle compared to differences between individuals with and without autism.

Prevalence and Phenomenology of Anxiety in Preschool-Aged Children with Autism Spectrum Disorder

Individuals with autism spectrum disorder (ASD) are at a higher risk for developing co-occurring anxiety symptoms and diagnosable anxiety disorders compared to children with neurotypical development (NTD). The objective of the current study was to characterize the prevalence and phenomenology of anxiety in preschool-aged children with ASD. Our sample consisted of preschoolers (M = 52.8 months, SD = 10.8 months) with ASD (n = 77, 66% with co-occurring intellectual disability, ID) and NTD (n = 55). We employed multi-method (questionnaire and semi-structured diagnostic interview) and multi-informant (parent- and teacher-report) assessments of anxiety. Children with ASD were significantly more likely to meet criteria for an anxiety disorder than children with NTD. Over 70% of our sample with ASD met DSM-5 criteria for an anxiety disorder, with Specific Phobia and Separation Anxiety Disorder being the most prevalent. A range of specific fears was endorsed in the group with ASD, many of which overlapped with ASD symptoms. Parents, but not teachers, also reported greater anxiety symptoms for children with ASD relative to the comparison sample. Prevalence and phenomenology of anxiety in our sample with ASD generally did not differ between those with and without co-occurring ID, with the exception of higher rates of generalized anxiety in those without ID. Results showed poor concordance between parent questionnaires and a semi-structured diagnostic interview in detecting clinically-elevated anxiety in children with ASD. Implications for clinical practice and research are discussed.

Overall prognosis of preschool autism spectrum disorder diagnoses

BACKGROUND

Autism spectrum disorder is a neurodevelopmental disorder characterised by social communication difficulties, restricted interests and repetitive behaviours. The clinical pathway for children with a diagnosis of autism spectrum disorder is varied, and current research suggests some children may not continue to meet diagnostic criteria over time.

OBJECTIVES

The primary objective of this review was to synthesise the available evidence on the proportion of preschool children who have a diagnosis of autism spectrum disorder at baseline (diagnosed before six years of age) who continue to meet diagnostic criteria at follow-up one or more years later (up to 19 years of age).

SEARCH METHODS

We searched MEDLINE, Embase, PsycINFO, and eight other databases in October 2017 and ran top-up searches up to July 2021. We also searched reference lists of relevant systematic reviews.

SELECTION CRITERIA

Two review authors independently assessed prospective and retrospective follow-up studies that used the same measure and process within studies to diagnose autism spectrum disorder at baseline and follow-up. Studies were required to have at least one year of follow-up and contain at least 10 participants. Participants were all aged less than six years at baseline assessment and followed up before 19 years of age.

DATA COLLECTION AND ANALYSIS

We extracted data on study characteristics and the proportion of children diagnosed with autism spectrum disorder at baseline and follow-up. We also collected information on change in scores on measures that assess the dimensions of autism spectrum disorder (i.e. social communication and restricted interests and repetitive behaviours). Two review authors independently extracted data on study characteristics and assessed risk of bias using a modified quality in prognosis studies (QUIPS) tool. We conducted a random-effects meta-analysis or narrative synthesis, depending on the type of data available. We also conducted prognostic factor analyses to explore factors that may predict diagnostic outcome.

MAIN RESULTS

In total, 49 studies met our inclusion criteria and 42 of these (11,740 participants) had data that could be extracted. Of the 42 studies, 25 (60%) were conducted in North America, 13 (31%) were conducted in Europe and the UK, and four (10%) in Asia. Most (52%) studies were published before 2014. The mean age of the participants was 3.19 years (range 1.13 to 5.0 years) at baseline and 6.12 years (range 3.0 to 12.14 years) at follow-up. The mean length of follow-up was 2.86 years (range 1.0 to 12.41 years). The majority of the children were boys (81%), and just over half (60%) of the studies primarily included participants with intellectual disability (intelligence quotient < 70). The mean sample size was 272 (range 10 to 8564). Sixty-nine per cent of studies used one diagnostic assessment tool, 24% used two tools and 7% used three or more tools. Diagnosis was decided by a multidisciplinary team in 41% of studies. No data were available for the outcomes of social communication and restricted and repetitive behaviours and interests. Of the 42 studies with available data, we were able to synthesise data from 34 studies (69% of all included studies; n = 11,129) in a meta-analysis. In summary, 92% (95% confidence interval 89% to 95%) of participants continued to meet diagnostic criteria for autism spectrum disorder from baseline to follow-up one or more years later; however, the quality of the evidence was judged as low due to study limitations and inconsistency. The majority of the included studies (95%) were rated at high risk of bias. We were unable to explore the outcomes of change in social communication and restricted and repetitive behaviour and interests between baseline and follow-up as none of the included studies provided separate domain scores at baseline and follow-up. Details on conflict of interest were reported in 24 studies. Funding support was reported by 30 studies, 12 studies omitted details on funding sources and two studies reported no funding support. Declared funding sources were categorised as government, university or non-government organisation or charity groups. We considered it unlikely funding sources would have significantly influenced the outcomes, given the nature of prognosis studies.

AUTHORS' CONCLUSIONS

Overall, we found that nine out of 10 children who were diagnosed with autism spectrum disorder before six years of age continued to meet diagnostic criteria for autism spectrum disorder a year or more later, however the evidence was uncertain. Confidence in the evidence was rated low using GRADE, due to heterogeneity and risk of bias, and there were few studies that included children diagnosed using a current classification system, such as the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) or the eleventh revision of the International Classification of Diseases (ICD-11). Future studies that are well-designed, prospective and specifically assess prognosis of autism spectrum disorder diagnoses are needed. These studies should also include contemporary diagnostic assessment methods across a broad range of participants and investigate a range of relevant prognostic factors.

Insistence on sameness for food space appropriation: An exploratory study on Brazilians with autism (self-)diagnosis in adulthood

Insistence on Sameness has been pathologized as a subtype of restricted, repetitive patterns of behavior, interests, or activities, in autism. We examined the meanings of Insistence on Sameness for autistic adults through the lens of critical autism studies and environmental psychology, exploring their foodways and experiences of food environments, in relation to eating out and grocery shopping, and their experiences of autism (self-)diagnosis. Data were collected from earlier individual email interviews with Brazilian adults on the autism spectrum ( N = 16), either formally diagnosed in adulthood ( n = 10) or self-diagnosed ( n = 6). Our thematic analysis generated the following three themes: (1) Insistence on Sameness behaviors in food space as participants’ efforts for human–environment optimization—reducing uncertainty, uncontrollability, and exposure to unwanted sensory stimuli and social interaction; (2) suppressed Insistence on Sameness behaviors for being considered weird habits; and (3) realization of Insistence on Sameness as an authentically autistic way of coping when self-knowledge deepens through autism (self-)diagnosis. Our findings suggest autistic adults’ insistence on sameness is an authentically autistic way to appropriate space and exercise their right to comfortably co-exist and live as human beings and as themselves.

Lay abstract

Insistence on sameness is common in autistic individuals and continues into adulthood. Research shows it may be a way to cope with environments because of their sensory sensitivity, intolerance to uncertainty, and anxiety. Understanding the reasons for insistence on sameness from the perspective of autistic adults is important. To study the meanings of insistence on sameness for autistic adults, we interviewed 16 Brazilian autistic adults. All 10 formally diagnosed participants were diagnosed in adulthood. Six participants identified as being on the autism spectrum without formal diagnosis. During the interviews by email, we first asked about participants’ experiences with autism diagnosis, either formal diagnosis or self-diagnosis. Then, we asked about their experiences in places for eating out and grocery shopping. We found they tended to always go to the same places and use protective accessories to eat or shop comfortably. But their such behaviors were considered weird habits, first by other people and later by themselves. While trying to control their weird habits because of social pressure, they often suffered anxiety and meltdowns. When they finally learned of their autism in adulthood, they began to better understand who they are and why they experience the environment differently from others. This new understanding taught them that their so-called weird habits are actually part of their authentically autistic ways to cope with the weirder world. This study suggests that autistic adults’ insistence on sameness is an authentically autistic way to exercise their right to comfortably co-exist and live as human beings and as themselves.

Neuroticism Drives Associations Between Repetitive Behaviors and Depression in Autistic Adults

Depression is more prevalent among autistic adults than neurotypical adults, yet risk factors are incompletely understood in this population. Some research groups have focused on relationships between negative repetitive thinking and depression in the autistic population, which may explain elevated prevalence rates in line with general population findings on rumination and internalizing disorders. Little is known about associations between depression and more prototypical repetitive cognitions and/or behaviors characteristic of autism (i.e., insistence on sameness [IS] and repetitive sensorimotor [RSM] behaviors). Therefore, the present study aimed to examine associations between IS, RSM behaviors, and depressive symptoms in 762 autistic adults, and whether observed effects are confounded by additional factors (e.g., demographic factors, trait neuroticism). To test if greater IS scores were associated with greater depressive symptoms on the BDI-II, a Bayesian linear regression was conducted with BDI-II scores (dependent variable) regressed on age, gender, educational level, RSM scores, and IS scores (independent variables). To test the effects of neuroticism on observed relationships, a second regression was conducted that included all predictors from the baseline model and neuroticism. Standardized regression coefficients were tested against an interval null hypothesis of [-0.1, 0.1] to assess for practical significance. Results indicated that IS exhibited a moderate positive relationship with depressive symptoms, while RSM behaviors provided only a slight increase in predictive ability. However in the second model, neuroticism exhibited a strong positive relationship with depressive symptoms, completely attenuating the effect of IS. Associations between RSM behaviors and depressive symptoms did not meet our criteria for practical significance, particularly when neuroticism was added to the model. Neither RSM nor IS moderated the effect of neuroticism on depression. The findings from this study add to the literature on risk factors in the pathway to depression in autism, and suggest opportunities for clinical translation to screening and intervention efforts. Screening for IS in autistic individuals is a common diagnostic practice in clinical and research settings that may be leveraged to also identify those at higher risk for depression, and increasing flexibility in daily life may promote emotional regulation and distress tolerance.

Delineating the autistic phenotype in children with neurofibromatosis type 1

Background

Existing research has demonstrated elevated autistic behaviours in children with neurofibromatosis type 1 (NF1), but the autistic phenotype and its relationship to other neurodevelopmental manifestations of NF1 remains unclear. To address this gap, we performed detailed characterisation of autistic behaviours in children with NF1 and investigated their association with other common NF1 child characteristics.

Methods

Participants were drawn from a larger cross-sectional study examining autism in children with NF1. The population analysed in this study scored above threshold on the Social Responsiveness Scale-Second Edition (T-score ≥ 60; 51% larger cohort) and completed the Autism Diagnostic Interview-Revised (ADI-R) and/or the Autism Diagnostic Observation Schedule-Second Edition (ADOS-2). All participants underwent evaluation of their intellectual function, and behavioural data were collected via parent questionnaires.

Results

The study cohort comprised 68 children (3–15 years). Sixty-three per cent met the ADOS-2 ‘autism spectrum’ cut-off, and 34% exceeded the more stringent threshold for ‘autistic disorder’ on the ADI-R. Social communication symptoms were common and wide-ranging, while restricted and repetitive behaviours (RRBs) were most commonly characterised by ‘insistence on sameness’ (IS) behaviours such as circumscribed interests and difficulties with minor changes. Autistic behaviours were weakly correlated with hyperactive/impulsive attention deficit hyperactivity disorder (ADHD) symptoms but not with inattentive ADHD or other behavioural characteristics. Language and verbal IQ were weakly related to social communication behaviours but not to RRBs.

Limitations

Lack of genetic validation of NF1, no clinical diagnosis of autism, and a retrospective assessment of autistic behaviours in early childhood.

Conclusions

Findings provide strong support for elevated autistic behaviours in children with NF1. While these behaviours were relatively independent of other NF1 comorbidities, the importance of taking broader child characteristics into consideration when interpreting data from autism-specific measures in this population is highlighted. Social communication deficits appear similar to those observed in idiopathic autism and are coupled with a unique RRB profile comprising prominent IS behaviours. This autistic phenotype and its relationship to common NF1 comorbidities such as anxiety and executive dysfunction will be important to examine in future research. Current findings have important implications for the early identification of autism in NF1 and clinical management.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13229-021-00481-3.

Zebrafish Modeling of Autism Spectrum Disorders, Current Status and Future Prospective

Autism spectrum disorder (ASD) refers to a complicated range of childhood neurodevelopmental disorders which can occur via genetic or non-genetic factors. Clinically, ASD is associated with problems in relationships, social interactions, and behaviors that pose many challenges for children with ASD and their families. Due to the complexity, heterogeneity, and association of symptoms with some neuropsychiatric disorders such as ADHD, anxiety, and sleep disorders, clinical trials have not yielded reliable results and there still remain challenges in drug discovery and development pipeline for ASD patients. One of the main steps in promoting lead compounds to the suitable drug for commercialization is preclinical animal testing, in which the efficacy and toxicity of candidate drugs are examined in vivo. In recent years, zebrafish have been able to attract the attention of many researchers in the field of neurological disorders such as ASD due to their outstanding features. The presence of orthologous genes for ASD modeling, the anatomical similarities of parts of the brain, and similar neurotransmitter systems between zebrafish and humans are some of the main reasons why scientists draw attention to zebrafish as a prominent animal model in preclinical studies to discover highly effective treatment approaches for the ASD through genetic and non-genetic modeling methods.

Social Deficits and Cerebellar Degeneration in Purkinje Cell Scn8a Knockout Mice

Mutations in the SCN8A gene encoding the voltage-gated sodium channel α-subunit Nav1. 6 have been reported in individuals with epilepsy, intellectual disability and features of autism spectrum disorder. SCN8A is widely expressed in the central nervous system, including the cerebellum. Cerebellar dysfunction has been implicated in autism spectrum disorder. We investigated conditional Scn8a knockout mice under C57BL/6J strain background that specifically lack Scn8a expression in cerebellar Purkinje cells (Scn8a ^flox/flox , L7Cre ⁺ mice). Cerebellar morphology was analyzed by immunohistochemistry and MR imaging. Mice were subjected to a battery of behavioral tests including the accelerating rotarod, open field, elevated plus maze, light-dark transition box, three chambers, male-female interaction, social olfaction, and water T-maze tests. Patch clamp recordings were used to evaluate evoked action potentials in Purkinje cells. Behavioral phenotyping demonstrated that Scn8a ^flox/flox , L7Cre ⁺ mice have impaired social interaction, motor learning and reversal learning as well as increased repetitive behavior and anxiety-like behaviors. By 5 months of age, Scn8a ^flox/flox , L7Cre ⁺ mice began to exhibit cerebellar Purkinje cell loss and reduced molecular thickness. At 9 months of age, Scn8a ^flox/flox , L7Cre ⁺ mice exhibited decreased cerebellar size and a reduced number of cerebellar Purkinje cells more profoundly, with evidence of additional neurodegeneration in the molecular layer and deep cerebellar nuclei. Purkinje cells in Scn8a ^flox/flox , L7Cre ⁺ mice exhibited reduced repetitive firing. Taken together, our experiments indicated that loss of Scn8a expression in cerebellar Purkinje cells leads to cerebellar degeneration and several ASD-related behaviors. Our study demonstrated the specific contribution of loss of Scn8a in cerebellar Purkinje cells to behavioral deficits characteristic of ASD. However, it should be noted that our observed effects reported here are specific to the C57BL/6 genome type.

Early trajectories of motor skills in infant siblings of children with autism spectrum disorder

Delays in motor development are not considered a core feature of autism spectrum disorder (ASD). Yet, recent studies of infant siblings of children with ASD suggest that early delays in motor skills may be associated with later delays in developmental areas considered to be core features of an ASD diagnosis. While these studies demonstrate the longitudinal association between core features and motor delays observed at single time points, there is considerable interest in studying the trajectories of motor development over the first 3 years of life. To accomplish this, we investigated early trajectories of motor development in a cohort of 499 infant siblings of children with ASD and 176 children with no family history of ASD. Data for the current study were drawn from the prospective, multi-site, Canadian Infant Sibling Study. We evaluated trajectories of fine and gross motor development over the first 3 years using group-based trajectory modeling. Our results show that membership for both fine and gross motor trajectory groups was related to expressive language skills, receptive language skills, ASD symptom severity scores, and diagnostic classification at age 3. These results provide evidence that the trajectory of a child's early motor development may have important prognostic implications in ASD.

Dissection of the relationship between anxiety and stereotyped self-grooming using the Shank3B mutant autistic model, acute stress model and chronic pain model

Self-grooming is an innate, cephalo-caudal progression of body cleaning behaviors that are found in normal rodents but exhibit repetitive and stereotyped patterns in several mouse models, such as autism spectrum disorders (ASDs). It is also recognized as a marker of stress and anxiety. Mice with Shank3B gene knockout (KO) exhibit typical ASD-like behavioral abnormalities, including stereotyped self-grooming and increased levels of anxiety. However, the exact relationship between anxiety and stereotyped self-grooming in certain types of animal models is not clear. We selected three animal models with high anxiety to compare their self-grooming parameters. First, we confirmed that Shank3B KO mice (ASD model), acute restraint stress mouse model (stress model), and chronic inflammatory pain mouse model (pain model) all showed increased anxiety levels in the open field test (OFT) and elevated plus maze (EPM). We found that only the ASD model and the stress model produced increased total grooming duration. The pain model only exhibited an increasing trend of mean self-grooming duration. We used the grooming analysis algorithm to examine the self-grooming microstructure and assess the cephalo-caudal progression of grooming behavior. The results showed distinct self-grooming microstructures in these three models. The anxiolytic drug diazepam relieved the anxiety level and the total time of grooming in the ASD and stress models. The grooming microstructure was not restored in Shank3B KO mice but was partially relieved in the stress model, which suggested that anxiety aggravated stereotyped self-grooming duration but not the grooming microstructure in the ASD mouse model. Our results indicated that stereotyped behavior and anxiety may be shared by separate, but interacting, neural circuits in distinct disease models, which may be useful to understand the mechanisms and develop potential treatments for stereotyped behaviors and anxiety.

Caregiver perspectives on the impact of uncertainty on the everyday lives of autistic children and their families

LAY ABSTRACT

Anxiety is common in autistic children. Research shows that this may be related to intolerance of uncertainty, which is a tendency to react negatively to uncertain situations. Understanding when, why and how autistic children respond to uncertainty is important in the development of anxiety programmes. We asked 53 (including 3 dyads) parents of autistic children about the types of uncertain situations that cause difficulties for their child and how uncertainty impacts on daily life for them and their families. We found that uncertain situations made autistic children and their families feel sad, worried, frustrated and angry through the themes: child's reactions to uncertainty, trying to reduce uncertainty, the impact of difficulties with uncertainty, the impact of uncertainty on parenting and the impact on parents. There are lots of situations that are anxiety provoking for autistic children because of uncertainty, such as school. Programmes to reduce anxiety and increase autistic children's ability to cope with everyday uncertain situations could improve quality of life for autistic children and their families.

Using the big data approach to clarify the structure of restricted and repetitive behaviors across the most commonly used autism spectrum disorder measures

BACKGROUND

Restricted and repetitive behaviors (RRB) in autism spectrum disorder (ASD) encompass several distinct domains. However, commonly used general ASD measures provide broad RRB scores rather than assessing separate RRB domains. The main objective of the current investigation was to conduct a psychometric evaluation of the ability of the Social Responsiveness Scale (SRS-2), the Social Communication Questionnaire (SCQ), the Autism Diagnostic Interview-Revised (ADI-R) and the Autism Diagnostic Observation Schedule (ADOS) to capture different RRB constructs.

METHODS

Exploratory Structural Equation Modeling (ESEM) was conducted using individual item-level data from the SRS-2, SCQ, ADI-R and the ADOS. Data were obtained from five existing publicly available databases. For the SRS-2, the final sample consisted of N = 16,761 individuals (Mage = 9.43, SD = 3.73; 18.5% female); for the SCQ, of N = 15,840 (Mage = 7.99, SD = 4.06; 18.1% female); for the ADI-R, of N = 8985 (Mage = 8.86, SD = 4.68; 19.4% female); and for the ADOS, of N = 6314 (Mage = 12.29, SD = 6.79; 17.7% female).

RESULTS

The three-factor structure provided the most optimal and interpretable fit to data for all measures (comparative fit index ≥ .983, Tucker Lewis index ≥ .966, root mean square error of approximation ≤ .028). Repetitive-motor behaviors, insistence on sameness and unusual or circumscribed interests factors emerged across all instruments. No acceptable fit was identified for the ADOS.

LIMITATIONS

The five datasets used here afforded a large as well as wide distribution of the RRB item scores. However, measures used for establishing convergent and divergent validity were only available for a portion of the sample.

CONCLUSIONS

Reported findings offer promise for capturing important RRB domains using general ASD measures and highlight the need for measurement development.

Case study: identification of anxiety and subsequent intervention in an adolescent male with autism, severe intellectual disability and self-injurious behaviour

Introduction: Anxiety disorders are highly prevalent in individuals with autism spectrum disorder (ASD), but knowledge is limited regarding identification and treatment of these disorders in individuals with ASD and more severe levels of intellectual disability (ID). The current case study aims to explore and describe the inpatient, psychiatric assessment in an adolescent male with ASD, severe ID and self-injurious behaviour (SIB) who was diagnosed with a co-occurring anxiety disorder. The study further aims to explore the implications of this diagnosis for subsequent intervention and care, including management of SIB. Materials and methods: Case study including multimodal, psychiatric assessment and subsequent intervention. Results: Following changes in care strategies attempting to incorporate the understanding of anxiety/trauma as contributing to SIB, a reduction of SIB was observed, and this reduced frequency was maintained when the patient was discharged from the inpatient setting. Conclusions: Though no causal inferences are possible, these experiences indicate that further research is needed regarding possible associations between SIB and anxiety in individuals with ASD, including implications for treatment. Experiences from the current case further indicate that it is possible to recognize and diagnose anxiety disorder in complex cases involving ASD, severe ID, limited verbal language skills, and severe SIB.