The development of autism spectrum disorders: variability and causal complexity

Multi-level treatment outcome evaluation in adolescents with autism spectrum disorder

BACKGROUND

Aberrant resting state electroencephalography (rsEEG) is a well-established indicator of psychopathological brain activity in clinical disorders. In Autism Spectrum Disorder (ASD), a substantial body of research reports reduced Alpha activity in the electrocortical resting state of affected individuals. However, effective interventions based on neurophysiological patterns and objective biological markers of treatment outcome remain scarce.

METHODS

In this randomized controlled trial, the primary objective was to examine rsEEG changes in adolescents with ASD following 24 sessions of slow cortical potential neurofeedback training (n = 21) compared to a treatment-as-usual control group (n = 20). A repeated-measures analysis of variance was used to assess group differences over time. Additionally, Pearson correlation analyses were conducted to exploratorily investigate associations between rsEEG measures and clinical psychopathology and affective well-being, as assessed via parental and self-report questionnaires at baseline and post-intervention.

RESULTS

Analyses revealed significant differences in the development of rsEEG between the intervention groups: while Alpha activity increased in the experimental neurofeedback group, it decreased in the control group, demonstrating an opposite trend. Exploratory analyses showed that Delta activity decreased in both groups, with a more pronounced decrease in the experimental group. Correlational analyses revealed significant associations between subjective-psychological and electrocortical levels: lower alpha power at baseline was related to greater severity of ASD symptoms, while both lower alpha and higher delta power were associated with greater negative affect at baseline. Increases in alpha power after NF-training were linked with enhanced positive affect, whereas reductions in delta power corresponded to decreases in negative affect.

CONCLUSIONS

This study provides insights into changes in resting-state neural activity before and after clinical interventions alongside clinical-psychological assessment, overcoming single-level assessments and emphasizing the need for multi-level outcome measures for a more comprehensive treatment evaluation.

CLINICAL TRIAL REGISTRATION

DRKS00012339.

A cross-sectional study of public knowledge and stigma towards autism spectrum disorder in Lebanon

Autism Spectrum Disorder (ASD) is a neurodevelopmental condition that requires public understanding to foster acceptance and reduce stigma. This study aimed to evaluate ASD knowledge and stigma among the Lebanese population and the factors influencing them. An online cross-sectional study was conducted between February and July 2022 among Lebanese adults. Participants completed a self-administered structured questionnaire that comprised a sociodemographic section and two validated scales serving the study's purpose (The Autism Stigma and Knowledge Questionnaire (ASK-Q) and The Autism Social Distance Scale). A total of 949 participants filled out the questionnaire. More than half of them had adequate knowledge of autism diagnosis and symptoms (57.9%), while only 6.6% and 9.6% showed adequate knowledge of its etiology and treatment, respectively. Additionally, 83.4% of the participants did not endorse stigma toward autism. The multivariate analysis taking the knowledge total score and subscales as the dependent variables showed that declaring prior knowledge of autism was significantly associated with better knowledge (Beta = 1.38) and higher stigma (Beta = 0.26). Furthermore, a higher knowledge score (Beta = - 0.06) and a declared prior knowledge of autism (Beta = - 0.62) were significantly associated with lower autism social distance. These findings highlight the need for targeted awareness campaigns to address knowledge gaps and further reduce stigma in Lebanon.

Experiencing Independence: Perspectives from Autistic Adults

Autism diagnostic criteria relate to difficulties in functioning across multiple developmental domains, that often impact on a person's independence. There are different ways to conceptualise and exercise independence, but no previous studies have questioned how autistic adults do so. This qualitative study aimed to understand how autistic adults define and experience independence. It was designed to further our understanding of how autistic adults account for and use coping strategies to overcome barriers to independent living and navigate their way to their desired level of independence. Twelve semi-structured interviews were conducted with autistic adults living in the United Kingdom. The data were analysed using reflexive thematic analysis. The researchers generated three major themes. The first theme 'Independence is "not a one-size-fits-all"' highlights that there is no one definition or concept of independence for autistic people; these are relative and uniquely individual. The second theme '"Being autistic has its setbacks" in a neurotypical world' describes the obstacles encountered by autistic adults seeking independence within a society that favours neurotypical norms. The third theme 'Finding ways of making it work' captures strategies autistic adults use in achieving or maintaining independence. The findings from this study provide a foundation for future research exploring domains of independence for autistic adults. The perceived desirability of achieving different degrees of in(ter)dependence and the fluctuating nature of self-sufficiency are explored through lived experience. Increasing understanding of barriers and challenges to independence has the potential to empower autistic adults and improve services and support.

Chemogenetic induction of CA1 hyperexcitability triggers indistinguishable autistic traits in asymptomatic mice differing in Ambra1 expression and sex

Among the genomic alterations identified as risk factors in mice models of autism spectrum disorders (ASD), heterozygous deletion of Ambra1 (Activating Molecule in Beclin1-Regulated Autophagy) triggers an ASD phenotype associated with hippocampal hyperexcitability exclusively in the female sex although Ambra1 protein is comparably expressed in the hippocampus of symptomatic females and asymptomatic males. Given the intricate relationship between Ambra1 deficiency and sex in the etiology of ASD, we took advantage of asymptomatic mice including Ambra1+/- males and wild-type (Wt) mice of both sexes to investigate whether their non-pathogenic variations in Ambra1 levels could underlie a differential susceptibility to exhibit ASD-like traits in response to experimental elevation of hippocampal excitability. Here we report that selective activation of inhibitory DREADD in CA1 parvalbumin-positive interneurons (PV-IN) reduces GABAergic currents onto pyramidal neurons (PN), causes social and attentional deficits, and augments the proportion of immature/thin spines in CA1 PN dendrites to the same extent in Ambra1+/- males and Wt mice of both sexes. Our findings show that the substantial hippocampal variations in pro-autophagic Ambra1 gene product shown by asymptomatic mice differing in mutation and/or sex do not underlie a differential reactivity to chemogenetic induction of idiopathic ASD.

Qualitative Ascriptions of Autistic Behavior by Non-Autistic College Students

In studies that assess perceptions of autistic people by non-autistic people, researchers often ask participants to review vignettes depicting fictional autistic characters. However, few studies have investigated whether non-autistic peers accurately identify these hypothetical individuals as being on the autism spectrum. Accurately ascribing autism as a cause of depicted behaviors likely influences perceptions about autistic peers. In this study, 469 college students (Mage = 18.62; 79.3% female) ascribed cause(s) of an autistic peers' behaviors as depicted in a written vignette. We reviewed and categorized open-ended responses into 16 categories. Non-autistic college students primarily attributed an autistic vignette character's behavior to non-autistic origins. The most commonly ascribed causes of behavior were: attention-deficit/hyperactivity disorder (55.4%), inattention symptoms (20.9%), autism (12.8%), generalized anxiety disorder (11.7%), hyperactivity (11.3%), an unspecified diagnosis (10.7%), an environmental influence (9.6), anxiety or insecurity (8.3%), irritability or anger or annoyance (6.0%), social anxiety disorder (5.3%), and learning disorder (5.1%). Additional ascribed causes include other mental health diagnoses; environmental stressors; and cognitive, emotional, behavioral, biological, or personality characteristics/etiologies. Non-autistic young adults may not always recognize their autistic peers as autistic, which may affect acceptance and inclusion. Future anti-stigma interventions should assess the impact of helping non-autistic peers to accurately identify and better understand behaviors associated with autism. Additionally, autism-focused researchers using vignettes should assess participants' awareness of the character as autistic and interpret their findings with this in mind.

Identifying Distinct Developmental Patterns of Brain Complexity in Autism: A Cross-Sectional Cohort Analysis Using the Autism Brain Imaging Data Exchange

AIM

Autistic traits exhibit neurodiversity with varying behaviors across developmental stages. Brain complexity theory, illustrating the dynamics of neural activity, may elucidate the evolution of autistic traits over time. Our study explored the patterns of brain complexity in autistic individuals from childhood to adulthood.

METHODS

We analyzed functional magnetic resonance imaging data from 1087 autistic participants and neurotypical controls aged 6 to 30 years within the ABIDE I (Autism Brain Imaging Data Exchange) data set. Sample entropy was calculated to measure brain complexity among 90 brain regions, utilizing an automated anatomical labeling template for voxel parcellation. Participants were grouped using sliding age windows with partial overlaps. We assessed the average brain complexity of the entire brain and brain regions for both groups across age categories. Cluster analysis was conducted using generalized association plots to identify brain regions with similar developmental complexity trajectories. Finally, the relationship between brain region complexity and autistic traits was examined.

RESULTS

Autistic individuals may tend toward higher whole-brain complexity during adolescence and lower complexity during childhood and adulthood, indicating possible distinct developmental trajectories. However, these results do not remain after Bonferroni correction. Two clusters of brain regions were identified, each with unique patterns of complexity changes over time. Correlations between brain region complexity, age, and autistic traits were also identified.

CONCLUSION

The study revealed brain complexity trajectories in autistic individuals, providing insight into the neurodiversity of autism and suggesting that age-related changes in brain complexity could be a potential neurodevelopmental marker for the dynamic nature of autism.

Metallomic Profiling of Autism Spectrum Disorder in Sarajevo Canton, Bosnia and Herzegovina: Insights from Hair Sample Analysis

The rising prevalence of autism spectrum disorder (ASD) in Bosnia and Herzegovina over the past decade is a pressing concern that underscores the urgent need to investigate its etiology. While this issue is recognized globally, there is a significant lack of data specific to Bosnia and Herzegovina, making comprehensive analysis essential. To address this gap, this study analyzed 41 hair samples from children categorized into three age subgroups (3-5 years, 6-9 years, 10-12 years) and differentiated by gender within both control and ASD groups. The concentrations of essential metals (Cu, Fe, Mn, Zn) as well as potentially toxic metals (Cd, Co, Ni, Pb) were measured using atomic absorption spectrometry (AAS). This research aims to provide valuable insights into the metallomic differences that may contribute to the understanding of ASD in this population. Females with autism spectrum disorder (ASD) exhibited elevated levels of Fe, Ni, and Cd across all age subgroups, surpassing reference values, while ASD males also showed increased Cd content. The control subgroup of 3-5-year-olds and all ASD female subgroups had Co levels exceeding the reference limit. Alarmingly, elevated Pb levels were found in all hair samples, with ASD males showing values that were twice as high as the reference. Statistically significant differences were identified in the concentrations of Cd, Fe, and Zn in females, as well as Pb in males, between the control and ASD groups. These findings underscore the urgent need for further research to elucidate the role of heavy metals in the etiology of ASD.

Are prosocial tendencies relevant for developmental psychopathology? The relations of prosocial behavior and empathy-related responding to externalizing problems, internalizing problems, and autism spectrum disorder

The field of developmental psychopathology tends to focus on the negative aspects of functioning. However, prosocial behavior and empathy-related responding - positive aspects of functioning- might relate to some aspects of psychopathology in meaningful ways. In this article, we review research on the relations of three types of developmental psychopathology- externalizing problems (EPs), internalizing problems (IPs), and Autism Spectrum Disorder (ASD) - to empathy-related responding (e.g., affective and cognitive empathy, sympathy, personal distress) and prosocial behavior. Empathy-related responding and prosocial behavior generally have been inversely related to EPs, although findings are sometimes reversed for young children and, for empathy, weak for reactive aggression. Some research indicates that children's empathy (often measured as emotional contagion) and personal distress are positively related to IPs, suggesting that strong sensitivity to others' emotions is harmful to some children. In contrast, prosocial behaviors are more consistently negatively related to IPs, although findings likely vary depending on the motivation for prosocial behavior and the recipient. Children with ASD are capable of prosocially and empathy-related responding, although parents report somewhat lower levels of these characteristics for ASD children compared to neurotypical peers. Issues in regard to measurement, motivation for prosociality, causal relations, and moderating and mediating factors are discussed.

Parental experiences and perspectives of healthcare providers' genetic testing recommendations for their children diagnosed with autism spectrum disorder in the United States

Although genetic testing is recommended for all children diagnosed with autism spectrum disorder (ASD) in the United States, it remains unclear how many parents have received and followed these recommendations. This study aimed to assess parental experiences and perspectives of healthcare providers' genetic testing recommendations. A total of 1043 parents of children with ASD from Simons Foundation Powering Autism Research for Knowledge completed an online survey. Only about one-third of the parents (34.2%) reported that their children's providers had recommended genetic testing. Factors associated with whether parents received these recommendations included the type of healthcare providers diagnosing ASD, parents' knowledge of genetic testing, the age of their children's diagnosis, and the presence of certain co-occurring medical conditions in their children. Our study also revealed that most parents (76.9%) who received recommendations had pursued genetic testing for their children. Adherence to the recommendations was associated with the characteristics of the parents (i.e., age and employment status) and children (i.e., gender), and their trust in the information from providers. The findings highlight the critical role of healthcare providers in facilitating genetic testing among families of children with ASD. Healthcare providers are recommended to increase their competencies and practice in providing genetic testing recommendations for ASD, assist parents in navigating testing challenges, and support parents through the testing process.

Development of personalized profiles of students with autism spectrum disorder for interactive interventions with robots to enhance language and social skills

The inclusion of students with autism spectrum disorder (ASD) in mainstream education (primary and secondary, in the range of 4-5 to 8-10 years old) is a complex task that has long challenged both educators and health professionals. However, the correct use of digital technologies such as personalization settings and interaction with robots has clearly shown how these new technologies can benefit ASD students. However, it is essential to characterize the profile, problems, and needs of each student, since it is not possible to generalize an accessible approach for all users. The work presented shows the creation and validation, through pilot tests, of an instrument that outlines the main needs of a student with ASD, based on behavioral variables. In a later phase, instructional sequences will be designed and adapted through digital tablets and interaction with a robot to improve specific aspects identified in the initial profile. The results demonstrate the method's ability to assess and prioritize profiles satisfactorily which helps create a design adjusted to each student. The first pilot tests have been well received by ASD students, who have shown increased interest in the contents and methods used in this approach. Motivation levels and engagement have also increased, and social interactions with their peers have improved.

Multiparametric Assays Capture Sex- and Environment-Dependent Modifiers of Behavioral Phenotypes in Autism Mouse Models

Background

Current phenotyping approaches for murine autism models often focus on one selected behavioral feature, making the translation onto a spectrum of autistic characteristics in humans challenging. Furthermore, sex and environmental factors are rarely considered. Here, we aimed to capture the full spectrum of behavioral manifestations in 3 autism mouse models to develop a "behavioral fingerprint" that takes environmental and sex influences under consideration.

Methods

To this end, we employed a wide range of classical standardized behavioral tests and 2 multiparametric behavioral assays-the Live Mouse Tracker and Motion Sequencing-on male and female Shank2, Tsc1, and Purkinje cell-specific Tsc1 mutant mice raised in standard or enriched environments. Our aim was to integrate our high dimensional data into one single platform to classify differences in all experimental groups along dimensions with maximum discriminative power.

Results

Multiparametric behavioral assays enabled a more accurate classification of experimental groups than classical tests, and dimensionality reduction analysis demonstrated significant additional gains in classification accuracy, highlighting the presence of sex, environmental, and genotype differences in our experimental groups.

Conclusions

Together, our results provide a complete phenotypic description of all tested groups, suggesting that multiparametric assays can capture the entire spectrum of the heterogeneous phenotype in autism mouse models.

Heterogeneity and convergence across seven neuroimaging modalities: a review of the autism spectrum disorder literature

Background

A growing body of literature classifies autism spectrum disorder (ASD) as a heterogeneous, complex neurodevelopmental disorder that often is identified prior to three years of age. We aim to provide a narrative review of key structural and functional properties that differentiate the neuroimaging profile of autistic youth from their typically developing (TD) peers across different neuroimaging modalities.

Methods

Relevant studies were identified by searching for key terms in PubMed, with the most recent search conducted on September 1, 2023. Original research papers were included if they applied at least one of seven neuroimaging modalities (structural MRI, functional MRI, DTI, MRS, fNIRS, MEG, EEG) to compare autistic children or those with a family history of ASD to TD youth or those without ASD family history; included only participants <18 years; and were published from 2013 to 2023.

Results

In total, 172 papers were considered for qualitative synthesis. When comparing ASD to TD groups, structural MRI-based papers (n = 26) indicated larger subcortical gray matter volume in ASD groups. DTI-based papers (n = 14) reported higher mean and radial diffusivity in ASD participants. Functional MRI-based papers (n = 41) reported a substantial number of between-network functional connectivity findings in both directions. MRS-based papers (n = 19) demonstrated higher metabolite markers of excitatory neurotransmission and lower inhibitory markers in ASD groups. fNIRS-based papers (n = 20) reported lower oxygenated hemoglobin signals in ASD. Converging findings in MEG- (n = 20) and EEG-based (n = 32) papers indicated lower event-related potential and field amplitudes in ASD groups. Findings in the anterior cingulate cortex, insula, prefrontal cortex, amygdala, thalamus, cerebellum, corpus callosum, and default mode network appeared numerous times across modalities and provided opportunities for multimodal qualitative analysis.

Conclusions

Comparing across neuroimaging modalities, we found significant differences between the ASD and TD neuroimaging profile in addition to substantial heterogeneity. Inconsistent results are frequently seen within imaging modalities, comparable study populations and research designs. Still, converging patterns across imaging modalities support various existing theories on ASD.

Visual fixation patterns to AAC displays are significantly correlated with motor selection for individuals with Down syndrome or individuals on the autism spectrum

Eye tracking research technologies are often used to study how individuals attend visually to different types of AAC displays (e.g. visual scene displays, grid displays). The assumption is that efficiency of visual search may relate to efficiency of motor selection necessary for communication via aided AAC; however, this assumption has not received direct empirical study. We examined the relation between speed of visual search and speed of motor selection of symbols. Ten individuals on the autism spectrum (AS; Study 1) and nine with Down syndrome (DS; Study 2) participated in a search task using simulated AAC displays with a main visual scene display (VSD) and a navigation bar of thumbnail VSDs. Participants were given an auditory prompt to find one of four thumbnail VSDs in the navigation bar. Eye tracking technologies measured how long it took participants to fixate visually on the thumbnail VSD, and recorded how long it took participants to select the thumbnail VSD with a finger. A statistically significant relationship emerged between visual fixation and selection latencies, confirming the positive relationship between visual processing and motor selection for both groups of participants. Eye tracking data may serve as a useful proxy measure for evaluating how display design influences selection of AAC symbols, especially when individuals are unwilling or unable to comply with traditional behaviorally-based assessment tasks.

Prenatal Diabetes and Obesity: Implications for Autism Spectrum Disorders in Offspring - A Comprehensive Review

Fetal brain development is an important determinant of neuropsychological performance in children. Any alterations in the intrauterine environment at different stages of pregnancy, such as maternal metabolic disorders, can lead to the development of chronic conditions in the offspring. Therefore, maternal diabetes, especially gestational diabetes mellitus, is an important factor in the development of pathological changes, such as miscarriage, fetal macrosomia, or neurodevelopmental disorders. During pregnancy, the hyperglycemic intrauterine environment adversely affects fetal brain development. A growing body of scientific research indicates that prenatal environmental factors, by affecting fetal brain development, can contribute to the appearance of autism spectrum disorders. According to the latest estimates from the International Diabetes Federation (2021), approximately 21.1 million live births worldwide (16.7%) have been affected by some form of hyperglycemia during pregnancy. The condition is more prevalent in low- and middle-income countries, where access to obstetric care is limited. The following factors have been identified as potential risk factors for gestational diabetes: advanced maternal age, overweight and obesity, family history of diabetes, and any form of diabetes. The purpose of this review is to summarize recent studies evaluating the effect of prenatal and maternal risk factors such as maternal pre-pregnancy diabetes, gestational diabetes, and obesity on the risk of developing autism spectrum disorder in offspring.

Early developmental milestone clusters of autistic children based on electronic health records

Autistic children vary in symptoms, co-morbidities, and response to interventions. This study aimed to identify clusters of autistic children with a distinct pattern of attaining early developmental milestones (EDMs). The clustering of 5836 autistic children was based on the attainment of 43 gross motor, fine motor, language, and social developmental milestones during the first 3 years of life as recorded in baby wellness visits. K-means cluster analysis detected four EDM clusters: mild (n = 1686); moderate (n = 1691); severe (n = 2265); and global (n = 194). The most prominent cluster differences were in the language domain. The global cluster showed earlier and greater developmental delay across domains, unique early gross motor delays, and more were born preterm via cesarean section. The severe cluster had poor language development prominently in the second year of life, and later fine motor delays. Moderate cluster had mainly language delays in the third year of life. The mild cluster mostly passed milestones. EDM clusters differed demographically, with higher socioeconomic status in mild cluster and lowest in global cluster. However, the severe cluster had more immigrant and non-Jewish mothers followed by the moderate cluster. The rates of parental concerns and provider developmental referrals were significantly higher in the global, followed by the severe, moderate, and mild EDM clusters. Autistic children's language and motor delay in the first 3 years can be grouped by common magnitude and onset profiles as distinct groups that may link to specific etiologies (like prematurity or genetics) and specific intervention programs. Early autism screening should be tailored to these different developmental profiles.

Assistive tools for classifying neurological disorders using fMRI and deep learning: A guide and example

BACKGROUND

Deep-learning (DL) methods are rapidly changing the way researchers classify neurological disorders. For example, combining functional magnetic resonance imaging (fMRI) and DL has helped researchers identify functional biomarkers of neurological disorders (e.g., brain activation and connectivity) and pilot innovative diagnostic models. However, the knowledge required to perform DL analyses is often domain-specific and is not widely taught in the brain sciences (e.g., psychology, neuroscience, and cognitive science). Conversely, neurological diagnoses and neuroimaging training (e.g., fMRI) are largely restricted to the brain and medical sciences. In turn, these disciplinary knowledge barriers and distinct specializations can act as hurdles that prevent the combination of fMRI and DL pipelines. The complexity of fMRI and DL methods also hinders their clinical adoption and generalization to real-world diagnoses. For example, most current models are not designed for clinical settings or use by nonspecialized populations such as students, clinicians, and healthcare workers. Accordingly, there is a growing area of assistive tools (e.g., software and programming packages) that aim to streamline and increase the accessibility of fMRI and DL pipelines for the diagnoses of neurological disorders.

OBJECTIVES AND METHODS

In this study, we present an introductory guide to some popular DL and fMRI assistive tools. We also create an example autism spectrum disorder (ASD) classification model using assistive tools (e.g., Optuna, GIFT, and the ABIDE preprocessed repository), fMRI, and a convolutional neural network.

RESULTS

In turn, we provide researchers with a guide to assistive tools and give an example of a streamlined fMRI and DL pipeline.

CONCLUSIONS

We are confident that this study can help more researchers enter the field and create accessible fMRI and deep-learning diagnostic models for neurological disorders.

Branched-chain amino acids as adjunctive-alternative treatment in patients with autism: a pilot study

The branched-chain amino acid (BCAA) is a group of essential amino acids that are involved in maintaining the energy balance of a human being as well as the homoeostasis of GABAergic, glutamatergic, serotonergic and dopaminergic systems. Disruption of these systems has been associated with the pathophysiology of autism while low levels of these amino acids have been discovered in patients with autism. A pilot open-label, prospective, follow-up study of the use of BCAA in children with autistic behaviour was carried out. Fifty-five children between the ages of 6 and 18 participated in the study from May 2015 to May 2018. We used a carbohydrate-free BCAA-powdered mixture containing 45·5 g of leucine, 30 g of isoleucine and 24·5 g of valine in a daily dose of 0·4 g/kg of body weight which was administered every morning. Following the initiation of BCAA administration, children were submitted to a monthly psychological examination. Beyond the 4-week mark, BCAA were given to thirty-two people (58·18 %). Six of them (10·9 %) discontinued after 4-10 weeks owing to lack of improvement. The remaining twenty-six children (47·27 %) who took BCAA for longer than 10 weeks displayed improved social behaviour and interactions, as well as improvements in their speech, cooperation, stereotypy and, principally, their hyperactivity. There were no adverse reactions reported during the course of the treatment. Although these data are preliminary, there is some evidence that BCAA could be used as adjunctive treatment to conventional therapeutic methods for the management of autism.

The neuroanatomical substrates of autism and ADHD and their link to putative genomic underpinnings

BACKGROUND

Autism spectrum disorders (ASD) are neurodevelopmental conditions accompanied by differences in brain development. Neuroanatomical differences in autism are variable across individuals and likely underpin distinct clinical phenotypes. To parse heterogeneity, it is essential to establish how the neurobiology of ASD is modulated by differences associated with co-occurring conditions, such as attention-deficit/hyperactivity disorder (ADHD). This study aimed to (1) investigate between-group differences in autistic individuals with and without co-occurring ADHD, and to (2) link these variances to putative genomic underpinnings.

METHODS

We examined differences in cortical thickness (CT) and surface area (SA) and their genomic associations in a sample of 533 individuals from the Longitudinal European Autism Project. Using a general linear model including main effects of autism and ADHD, and an ASD-by-ADHD interaction, we examined to which degree ADHD modulates the autism-related neuroanatomy. Further, leveraging the spatial gene expression data of the Allen Human Brain Atlas, we identified genes whose spatial expression patterns resemble our neuroimaging findings.

RESULTS

In addition to significant main effects for ASD and ADHD in fronto-temporal, limbic, and occipital regions, we observed a significant ASD-by-ADHD interaction in the left precentral gyrus and the right frontal gyrus for measures of CT and SA, respectively. Moreover, individuals with ASD + ADHD differed in CT to those without. Both main effects and the interaction were enriched for ASD-but not for ADHD-related genes.

LIMITATIONS

Although we employed a multicenter design to overcome single-site recruitment limitations, our sample size of N = 25 individuals in the ADHD only group is relatively small compared to the other subgroups, which limits the generalizability of the results. Also, we assigned subjects into ADHD positive groupings according to the DSM-5 rating scale. While this is sufficient for obtaining a research diagnosis of ADHD, our approach did not take into account for how long the symptoms have been present, which is typically considered when assessing ADHD in the clinical setting.

CONCLUSION

Thus, our findings suggest that the neuroanatomy of ASD is significantly modulated by ADHD, and that autistic individuals with co-occurring ADHD may have specific neuroanatomical underpinnings potentially mediated by atypical gene expression.

De-implementation of Low-Value Practices for Autism Spectrum Disorder

Due to a variety of factors, Autism Spectrum Disorder (ASD) has long been tethered to use of low-value practice (LVP), arguably moreso than any other psychiatric or neurodevelopmental condition. Although dissemination of empirically supported treatments (EST) for autistic individuals has expanded markedly over the past decade, there has not been concomitant reduction in the use of LVP. It is critical that clinicians and scientists not only promote the implementation of EST, but also facilitate the de-implementation (abandonment and/or divestment) of ineffective or harmful practices. In this review, we describe a data-driven approach that can be used to identify LVP, drawing from established criteria for identification of evidence-based treatments (e.g., APA Division 12, National Clearinghouse on Autism Evidence and Practice; SAMHSA), as well as broader considerations such as social validity, cost, and parsimony. Herein, a data-based approach to LVP identification is proposed with a goal of improving quality of service access. Within an implementation science framework, we identify specific facilitators that sustain LVP use, and recommendations for subsequent de-implementation strategies are offered.

Metabolomics: Perspectives on Clinical Employment in Autism Spectrum Disorder

Precision medicine is imminent, and metabolomics is one of the main actors on stage. We summarize and discuss the current literature on the clinical application of metabolomic techniques as a possible tool to improve early diagnosis of autism spectrum disorder (ASD), to define clinical phenotypes and to identify co-occurring medical conditions. A review of the current literature was carried out after PubMed, Medline and Google Scholar were consulted. A total of 37 articles published in the period 2010-2022 was included. Selected studies involve as a whole 2079 individuals diagnosed with ASD (1625 males, 394 females; mean age of 10, 9 years), 51 with other psychiatric comorbidities (developmental delays), 182 at-risk individuals (siblings, those with genetic conditions) and 1530 healthy controls (TD). Metabolomics, reflecting the interplay between genetics and environment, represents an innovative and promising technique to approach ASD. The metabotype may mirror the clinical heterogeneity of an autistic condition; several metabolites can be expressions of dysregulated metabolic pathways thus liable of leading to clinical profiles. However, the employment of metabolomic analyses in clinical practice is far from being introduced, which means there is a need for further studies for the full transition of metabolomics from clinical research to clinical diagnostic routine.

Exploring potential impacts of pregnancy-related maternal immune activation and extracellular vesicles on immune alterations observed in autism spectrum disorder

Autism Spectrum Disorder (ASD) is a set of neurodevelopmental disorders usually observed in early life, with impacts on behavioral and social skills. Incidence of ASD has been dramatically increasing worldwide, possibly due to increase in awareness/diagnosis as well as to genetic and environmental triggers. Currently, it is estimated that ∼1% of the world population presents ASD symptoms. In addition to its genetic background, environmental and immune-related factors also influence the ASD etiology. In this context, maternal immune activation (MIA) has recently been suggested as a component potentially involved in ASD development. In addition, extracellular vesicles (EVs) are abundant at the maternal-fetal interface and are actively involved in the immunoregulation required for a healthy pregnancy. Considering that alterations in concentration and content of EVs have also been associated with ASD, this article raises a debate about the potential roles of EVs in the processes surrounding MIA. This represents the major differential of the present review compared to other ASD studies. To support the suggested correlations and hypotheses, findings regarding the roles of EVs during pregnancy and potential influences on ASD are discussed, along with a review and update concerning the participation of infections, cytokine unbalances, overweight and obesity, maternal anti-fetal brain antibodies, maternal fever, gestational diabetes, preeclampsia, labor type and microbiota unbalances in MIA and ASD.

Prenatal maternal stress and the severity of autism spectrum disorder: A cross-sectional study

Autism spectrum disorder (ASD) is a neurodevelopmental disorder linked to several genetic and environmental factors including antenatal stress. Hence, we aimed to examine whether a mother's stress during pregnancy is associated with the severity of autism spectrum disorder in children. The study was conducted with 459 mothers of children with autism (aged 2-14 years) who were attending rehabilitation and educational centers in the two major cities of Makkah and Jeddah in Saudi Arabia. Environmental factors, consanguinity, and ASD family history were assessed using a validated questionnaire. The Prenatal Life Events Scale questionnaire was used to assess whether the mothers were exposed to stress during pregnancy. Two models of ordinal regression analysis were conducted including gender, child age maternal age, parental age, maternal education, parental education, income nicotine exposure, mother taking medication during pregnancy, family history of ASD, gestation, consanguinity, exposure of prenatal life events (in model 1), and severity of prenatal life events (in model 2). Family history of ASD showed a statistically significant association with the severity of ASD in both regression models (p = .015, odds ratio [OR]: 4.261 in Model 1, and p = .014, OR: 4.901 in model 2). In model 2, the moderate severity prenatal life events showed higher statistically significant adjusted odds ratio for ASD severity compared to no stress (p = .031; OR: 3.82). Within the limitations of this study, prenatal stressors showed some potential contribution to ASD severity. Family history of ASD was the only factor that showed a persistent association with ASD severity. A study that assesses the effect of COVID-19 stress on ASD prevalence and severity is recommended.

Resilience among Parents and Children with Autism Spectrum Disorder

Resilience plays a pivotal role to offset stress among families of children with autism spectrum disorder (ASD). Although the majority of previous studies investigated resilience in parents, it is unclear what factors contribute to resilience in children. Thus, we aimed to explore resilience experienced by parents of children with ASD and how it affects children’s resilience. We invited 50 parents of a child with ASD, 13 years old or younger, across various Canadian provinces in an online survey. Parental resilience was positively associated with household income and negatively associated with parental stress. Resilience in children with ASD was positively associated with their social participation at home and community. Findings indicate a relationship between resilience in children with ASD and their participation, suggesting new ways to increase resilience in children with ASD by enhancing their participation.

Evaluating causal psychological models: A study of language theories of autism using a large sample

We used a large convenience sample (n = 22,223) from the Simons Powering Autism Research (SPARK) dataset to evaluate causal, explanatory theories of core autism symptoms. In particular, the data-items collected supported the testing of theories that posited altered language abilities as cause of social withdrawal, as well as alternative theories that competed with these language theories. Our results using this large dataset converge with the evolution of the field in the decades since these theories were first proposed, namely supporting primary social withdrawal (in some cases of autism) as a cause of altered language development, rather than vice versa. To accomplish the above empiric goals, we used a highly theory-constrained approach, one which differs from current data-driven modeling trends but is coherent with a very recent resurgence in theory-driven psychology. In addition to careful explication and formalization of theoretical accounts, we propose three principles for future work of this type: specification, quantification, and integration. Specification refers to constraining models with pre-existing data, from both outside and within autism research, with more elaborate models and more veridical measures, and with longitudinal data collection. Quantification refers to using continuous measures of both psychological causes and effects, as well as weighted graphs. This approach avoids "universality and uniqueness" tests that hold that a single cognitive difference could be responsible for a heterogeneous and complex behavioral phenotype. Integration of multiple explanatory paths within a single model helps the field examine for multiple contributors to a single behavioral feature or to multiple behavioral features. It also allows integration of explanatory theories across multiple current-day diagnoses and as well as typical development.

Combined Gait and Grasping in Autistic and Non-Autistic Youths

This study was designed to extend research on motor skill development in autism spectrum disorder using a dual-task skill. Nine autistic and 18 non-autistic youths walked without grasping or while reaching to grasp a small or large object. Step extremity ratio, percent time in double support, and normalized speed were quantified. We hypothesized that gait would differ between autistic and non-autistic youth and that differences would be moderated by the phase (approach and grasp) and the complexity of the task (walking and grasping versus walking alone). Although gait parameters were similar during the walking-only trials, the combined task resulted in slower speed and shorter steps in autistic youth, particularly during the grasp phase. These findings, while in a small sample, offer preliminary evidence that autistic youth who show typical gait during simple assessments of motor ability may have difficulties in more complex tasks that require the coordination of movements.

Sensory Profile of Children and Adolescents with Autism Spectrum Disorder and Tip-Toe Behavior: Results of an Observational Pilot Study

Atypical sensory processing is frequently reported in persons with autism spectrum disorders (ASD), and it is one of the described diagnostic criteria for ASD. There is also mounting literature supporting the presence of motor impairments in individuals with ASD. Among these motor signs, tip-toe behavior (TTB) is a possible clinical finding, but its etiology is not clearly understood. It is suggested that TTB in ASD could be a sign of a sensory modulation impairment, but evidence is lacking and controversial. The main aim of this pilot study is to explore sensory features in a sample (4 females; 28 males) of children and adolescents with ASD (age range: 7-18). All participants also presented Intellectual Disability. Participants were divided in two groups, matched for age and gender, on the basis of the presence or absence of TTB (16 ASD TTB group vs. 16 ASD NO-TTB group) and then evaluated by using the Short Sensory Profile. We found that both ASD groups tend to significantly present sensory-related behavioral symptoms, but ASD TTB individuals more frequently showed the specific pattern of "under responsive/seeks sensation" than ASD NO-TTB individuals. These preliminary findings support that sensory-motor features might be taken into consideration when rehabilitation for TTB in children and adolescents with ASD is necessary.

Supervised Approach to Identify Autism Spectrum Neurological Disorder via Label Distribution Learning

Autism Spectrum Disorder (ASD) is a complicated collection of neurodevelopmental illnesses characterized by a variety of developmental defects. It is a binary classification system that cannot cope with reality. Furthermore, ASD, data label noise, high dimension, and data distribution imbalance have all hampered the existing classification algorithms. As a result, a new ASD was proposed. This strategy employs label distribution learning (LDL) to deal with label noise and uses support vector regression (SVR) to deal with sample imbalance. The experimental results show that the proposed method balances the effects of majority and minority classes on outcomes. It can effectively deal with imbalanced data in ASD diagnosis, and it can help with ASD diagnosis. This study presents a cost-sensitive approach to correct sample imbalance and uses a support vector regression (SVR)-based method to remove label noise. The label distribution learning approach overcomes high-dimensional feature classification issues by mapping samples to the feature space and then diagnosing multiclass ASD. This technique outperforms previous methods in terms of classification performance and accuracy, as well as resolving the issue of unbalanced data in ASD diagnosis.

Advanced paternal age diversifies individual trajectories of vocalization patterns in neonatal mice

Infant crying is a communicative behavior impaired in neurodevelopmental disorders (NDDs). Because advanced paternal age is a risk factor for NDDs, we performed computational approaches to evaluate how paternal age affected vocal communication and body weight development in C57BL/6 mouse offspring from young and aged fathers. Analyses of ultrasonic vocalization (USV) consisting of syllables showed that advanced paternal age reduced the number and duration of syllables, altered the syllable composition, and caused lower body weight gain in pups. Pups born to young fathers had convergent vocal characteristics with a rich repertoire, whereas those born to aged fathers exhibited more divergent vocal patterns with limited repertoire. Additional analyses revealed that some pups from aged fathers displayed atypical USV trajectories. Thus, our study indicates that advanced paternal age has a significant effect on offspring's vocal development. Our computational analyses are effective in characterizing altered individual diversity.

Identifying and describing subtypes of spontaneous empathic facial expression production in autistic adults

BACKGROUND

It is unclear whether atypical patterns of facial expression production metrics in autism reflect the dynamic and nuanced nature of facial expressions across people or a true diagnostic difference. Furthermore, the heterogeneity observed across autism symptomatology suggests a need for more adaptive and personalized social skills programs. Towards this goal, it would be useful to have a more concrete and empirical understanding of the different expressiveness profiles within the autistic population and how they differ from neurotypicals.

METHODS

We used automated facial coding and an unsupervised clustering approach to limit inter-individual variability in facial expression production that may have otherwise obscured group differences in previous studies, allowing an "apples-to-apples" comparison between autistic and neurotypical adults. Specifically, we applied k-means clustering to identify subtypes of facial expressiveness in an autism group (N = 27) and a neurotypical control group (N = 57) separately. The two most stable clusters from these analyses were then further characterized and compared based on their expressiveness and emotive congruence to emotionally charged stimuli.

RESULTS

Our main finding was that a subset of autistic adults in our sample show heightened spontaneous facial expressions irrespective of image valence. We did not find evidence for greater incongruous (i.e., inappropriate) facial expressions in autism. Finally, we found a negative trend between expressiveness and emotion recognition within the autism group.

CONCLUSION

The results from our previous study on self-reported empathy and current expressivity findings point to a higher degree of facial expressions recruited for emotional resonance in autism that may not always be adaptive (e.g., experiencing similar emotional resonance regardless of valence). These findings also build on previous work indicating that facial expression intensity is not diminished in autism and suggest the need for intervention programs to focus on emotion recognition and social skills in the context of both negative and positive emotions.

Daylong Mobile Audio Recordings Reveal Multitimescale Dynamics in Infants' Vocal Productions and Auditory Experiences

The sounds of human infancy-baby babbling, adult talking, lullaby singing, and more-fluctuate over time. Infant-friendly wearable audio recorders can now capture very large quantities of these sounds throughout infants' everyday lives at home. Here, we review recent discoveries about how infants' soundscapes are organized over the course of a day based on analyses designed to detect patterns at multiple timescales. Analyses of infants' day-long audio have revealed that everyday vocalizations are clustered hierarchically in time, vocal explorations are consistent with foraging dynamics, and musical tunes are distributed such that some are much more available than others. This approach focusing on the multi-scale distributions of sounds heard and produced by infants provides new, fundamental insights on human communication development from a complex systems perspective.

Diversity of Intelligence is the Norm Within the Autism Spectrum: Full Scale Intelligence Scores Among Children with ASD

Although previous research helped to define differences in intelligence between neurotypicals and those with ASD, results were limited by small sample sizes or restricted subtests. Using data from the NIMH Data Archive, this study examined the intelligence of children with ASD (N = 671). Results demonstrate an average standard deviation of 25.75, which is 1.72 times greater than that of the normative sample for the WISC-III. Moreover, students with ASD are 12 times more likely than the general population of students to score within the intellectual disability range, but are also 1.5 times more likely to score in the superior range, suggesting that more students with ASD should be considered for giftedness. Determining the diversity of intelligence among those with ASD has implications for research, clinical practice, and neurological understanding.

Therapeutic Riding or Mindfulness: Comparative Effectiveness of Two Recreational Therapy Interventions for Adolescents with Autism

Therapeutic riding (THR) and HeartMath (HM) mindfulness-based interventions have promise for reducing stress in adolescents with autism spectrum disorder. In three 10-week periods, this study compared THR, HM, and control on salivary cortisol, self-reported stress, parent-reported social responsiveness, and heart-rate variability. This crossover design included 27 participants (12-21 years) randomly assigned to order of intervention. Findings suggest that HM and THR manualized protocols are equally beneficial in decreasing cortisol levels immediately following a session, but HM sessions had more impact on heart-rate variability. There was no significant effect on follow-up cortisol levels within a week after either intervention, but THR had more impact on decreasing some self-reported stressors.

The Floor Effect on the ABAS-II in Adolescents with Autism Spectrum Disorder

The present study aimed at enhancing the assessment of adaptive behavior in adolescents with Autism Spectrum Disorder trough the Adaptive Behavior Assessment System-Second Edition. To overcome the limits underpinning floor effect, which are commonly observed with the traditional methods, the statistical Hessl method and its revision by Orsini, Pezzuti and Hulbert was adopted. The results showed a more variation using the former method compared to the latter: a greater impairment in Social versus Leisure skills emerged. Regarding the Conceptual domain, a greater deficit in Functional Academics was observed. In the Practical domain, we found a greater impairment in Self-Care skills. Conversely, Home Living skills appeared as a strength compared to other skills. The results are discussed in reference to literature.

Adult Trauma Patients with Autism Spectrum Disorder: A Case-Control Study to Evaluate Disparities After Injury

BACKGROUND

Adult trauma patients with autism spectrum disorder (ASD) may have distinct care needs that have not been previously described. We hypothesized that due to differences in clinical care and disposition issues, injured adults with ASD would have increased lengths of stay, higher mortality, and increased rates of complications compared to adults without ASD.

METHODS

The Pennsylvania Trauma Outcomes Study database was queried from 2010-2018 for trauma patients with ASD. Case-control matching was performed for two controls per ASD patient accounting for age, gender, injury mechanism, and injury severity score. Primary outcomes included length of stay, mortality, and complication rate. Univariate analysis compared presentation and clinical care between the two groups. Multivariate regression and Kaplan-Meier curves modeled length of stay. Significance was defined as p < 0.05.

RESULTS

A total of 185 patients with ASD were matched to 370 controls. Age (mean +/- standard deviation) was 33.4 +/- 16.5 years. Gender was 81.1% male. Mechanisms were 88.1% blunt, 5.9% penetrating, and 5.9% burns. Significant clinical differences identified in patients with ASD vs. case-controls included presenting verbal GCS (median [IQR]) (5 [2] vs. 5 [0], p < 0.01), proportion of patients intubated at presentation (20.0% vs. 13.0%, p = 0.031), and hospital length of stay (4 [6] days vs. 3 [4] days, p = 0.002). Adult patients with ASD were less likely to be discharged home and more often discharged to a skilled nursing facility (p < 0.01). There were no differences in mortality, rates of complications, imaging, or operations. Multivariate regression analysis controlling for demographic and clinical differences revealed the diagnosis of ASD independently contributed 3.13 days (95% Confidence Interval: 1.85 to 4.41 days) to injured adults' length of stay. Kaplan-Meier curves showed injured patients with ASD were less likely to be discharged than case-controls starting from time of admission (log rank test, p < 0.001).

CONCLUSIONS

This statewide analysis suggests injured patients with ASD have increased lengths of stay without other clinical or outcome differences. Given significant differences in discharge destination, these findings support early involvement of a multidisciplinary care collaborative. Further research is needed to identify factors that contribute to disparities in care for adults with ASD.

Association of breastfeeding status with risk of autism spectrum disorder: A systematic review, dose-response analysis and meta-analysis

Current evidence indicates that nutritional status in newborns, especially the duration of breastfeeding, plays a key role in the pathogenesis of autism spectrum disorder. We aimed to systematically review and meta-analyze relevant studies with findings of an association between autism spectrum disorder and breastfeeding patterns, and undertook an extensive dose-response analysis to interpret the results more accurately. Ten electronic databases and manual search of reference lists were used to identify relevant studies in September 2018. Dose-response and conventional meta-analysis were conducted by the random-effects model. The study protocol was registered in PROSPERO with CRD42016043128. Seven case-control studies were found in which the association between ever breastfeeding and risk of autism spectrum disorder was investigated. We found a 58 % decrease in the risk of autism spectrum disorder with ever breastfeeding and a 76 % decrease in the risk with exclusive breastfeeding. According to our dose-response meta-analysis, breastfeeding for 6 months was associated with a 54 % reduction in the risk. In the conventional meta-analysis, breastfeeding for 12-24 months was associated with the most significant reduction in the risk of autism spectrum disorder. Our results highlight the importance of breastfeeding to decrease the risk of autism spectrum disorder.

Association of Folic Acid Supplementation During Pregnancy With the Risk of Autistic Traits in Children Exposed to Antiepileptic Drugs In Utero

Importance

Strategies to prevent autism in children exposed to antiepileptic drugs (AEDs) during pregnancy are important.

Objective

To explore whether folic acid supplementation and folate status in pregnancy are associated with reduced risk of autistic traits owing to in utero AED exposure.

Design, Setting, and Participants

The population-based, prospective Norwegian Mother and Child Cohort Study approached Norwegian-speaking women attending routine ultrasonographic examinations from June 1999 through December 31, 2008 (163 844 of 277 702 women refused). No exclusion criteria were applied beyond language. Questionnaires during and after pregnancy, analysis of blood samples, and linkage to the Medical Birth Registry of Norway were performed. Children aged 18 to 36 months of women with available information on use of AEDs and of folic acid supplementation (n = 104 946) were included in the analysis from March 1, 2016, through June 13, 2017.

Exposures

Maternal folic acid supplementation 4 weeks before to 12 weeks after conception. Plasma folate concentration was analyzed at gestational weeks 17 to 19.

Main Outcomes and Measures

Autistic traits were evaluated using the Modified Checklist for Autism in Toddlers and Social Communication Questionnaire. Odds ratios (ORs) for autistic traits in children by maternal use vs nonuse of folic acid supplements were adjusted for maternal health and socioeconomic factors. Folate concentrations and folic acid doses were associated with the degree of autistic traits.

Results

The overall mean (SD) age of the 104 946 mothers of participating children was 29.8 (4.6) years, with complete information available for analysis in 103 868. Mean (SD) age of women with epilepsy who received AED treatment was 29.4 (4.9); women with epilepsy who did not receive AED treatment, 29.1 (4.9); and without epilepsy, 29.8 (4.6) years. In the 335 children exposed to AEDs, the risk for autistic traits was significantly higher at 18 months of age (adjusted OR [AOR], 5.9; 95% CI, 2.2-15.8) and 36 months of age (AOR, 7.9; 95% CI, 2.5-24.9) when their mothers had not used folic acid supplements compared with children of mothers who had used supplements. Among women without epilepsy, the corresponding risks were lower at 18 months of age (AOR, 1.3; 95% CI, 1.2-1.4) and 36 months of age (AOR, 1.7; 95% CI, 1.5-1.9); among the 389 children of women with untreated epilepsy, the corresponding risks were not significant at 18 months of age (AOR, 1.0; 95% CI, 0.4-3.0) and 36 months of age (AOR, 2.5; 95% CI, 0.4-16.6). Degree of autistic traits was inversely associated with maternal plasma folate concentrations (β = -0.3; P = .03) and folic acid doses (β = -0.5; P < .001). Concentrations of AEDs were not associated with the degree of autistic traits.

Conclusions and Relevance

Risk of autistic traits in children exposed to AEDs in utero may be mitigated by periconceptional folic acid supplementation and folate status. Fertile women using AEDs should take folic acid supplements continuously.

ANK2 autism mutation targeting giant ankyrin-B promotes axon branching and ectopic connectivity

Giant ankyrin-B (ankB) is a neurospecific alternatively spliced variant of ANK2, a high-confidence autism spectrum disorder (ASD) gene. We report that a mouse model for human ASD mutation of giant ankB exhibits increased axonal branching in cultured neurons with ectopic CNS axon connectivity, as well as with a transient increase in excitatory synapses during postnatal development. We elucidate a mechanism normally limiting axon branching, whereby giant ankB localizes to periodic axonal plasma membrane domains through L1 cell-adhesion molecule protein, where it couples microtubules to the plasma membrane and prevents microtubule entry into nascent axon branches. Giant ankB mutation or deficiency results in a dominantly inherited impairment in selected communicative and social behaviors combined with superior executive function. Thus, gain of axon branching due to giant ankB-deficiency/mutation is a candidate cellular mechanism to explain aberrant structural connectivity and penetrant behavioral consequences in mice as well as humans bearing ASD-related ANK2 mutations.

The Relation Between Walking and Language in Infant Siblings of Children With Autism Spectrum Disorder

In typical development, walk onset is accompanied by increased language growth (e.g., Walle & Campos, 2014). The present study explored whether this relation may be disrupted in the infant siblings of children with autism spectrum disorder (ASD; heightened risk of receiving an ASD diagnosis; HR), a population exhibiting substantial variability in motor and language development (e.g., Gamliel, Yirmiya, & Sigman, 2007; Landa & Garrett-Mayer, 2006). Receptive and expressive language were examined across the transition to walking in three groups of HR infants (no diagnosis, language delay, and ASD; N = 91, 8-18 months) and in infants with no family history of ASD (N = 25; 9-15 months). Only infants with an eventual ASD diagnosis did not show increased language growth following walk onset.

Cord and Early Childhood Plasma Adiponectin Levels and Autism Risk: A Prospective Birth Cohort Study

Emerging research suggests that adiponectin, a cytokine produced by adipose tissue, may be implicated in ASD. In this prospective birth cohort study (n = 847), we assessed the association between cord, early childhood plasma adiponectin and the risk of developing ASD. ASD was defined based on ICD codes of physician diagnosis. Cord adiponectin levels were inversely associated with ASD risk (aOR 0.50; 95% CI 0.33, 0.77), independent of preterm birth, early childhood adiponectin and other known ASD risk factors. Early childhood adiponectin, assessed prior to ASD diagnosis, was associated with lower risk of ASD, which attenuated after adjusting for cord adiponectin, indicating the relative importance of cord adiponectin in ASD risk. Further research is warranted to confirm our findings and elucidate biological mechanisms.

Autism spectrum disorders: let's talk about glucose?

Autism spectrum disorders (ASD) are characterized by disconnectivity due to disordered neuronal migration, and by neuronal mitochondrial dysfunction. Different pathways involved in neuronal migration are affected by intrauterine hyperglycemia and hyperinsulinemia, while prolonged neonatal hypoglycemia may cause mitochondrial dysfunction. Our hypothesis was that conditions leading to intrauterine hyperglycemia or neonatal hypoglycemia would influence ASD pathogenesis. In this study, we identified risk factors for ASD by searching PubMed with the MeSH terms "autism spectrum disorder" and "risk factors". We then analyzed the relationship between the risk factors and glucose abnormalities in the mother and the offspring. The relationship between glucose abnormalities and risk factors such as obesity, excessive maternal weight gain, or diabetes mellitus is evident. For risk factors such as malformations or exposure to selective serotonin reuptake inhibitors, the relationship is speculative. In rodents, for example, intrauterine hyperglycemia is associated with malformations, independent of maternal diabetes. In their turn, selective serotonin reuptake inhibitors reduce the signs of neonatal hypoglycemia. Going undetected, prolonged hypoglycemia may harm the neonatal brain. Importantly, our group demonstrated that either high-carbohydrate diets or physical inactivity the day before delivery may influence neonatal glycemia. In that study, of 158 neonates selected to be screened according to maternal lifestyle risk factors, 48 had hypoglycemia. Of note, five of them had not been identified with current screening programs. Controlled studies are needed to clarify whether maternal interventions aiming at maintaining glycemic control, together with screening programs for neonatal hypoglycemia based on maternal lifestyle risk factors and on exposure to specific prenatal medications can reduce the prevalence of ASD.

Autism: One or many spectrums?

Our conceptualisation of autism spectrum disorder has changed over time, with recent classifications reflecting a heterogeneous clinical presentation now regularly encountered in routine general paediatric practice. As the prevalence of autism and associated demands for services have increased so has research into understanding the cause and trials aimed at providing best care and intervention. However, the heterogeneity of autism has meant that no single aetiology can account for all differences in presentation, and not all children benefit from broad-based interventions. Now is the time to rethink how best to understand individual differences in order to focus research efforts and take steps towards more sophisticated strategies that go beyond the behaviours we look for when making an autism diagnosis. We suggest adopting a dimensional approach to autism assessment, with the consideration of eight spectrums of abilities, ways of thinking and behaviour. This eight-spectrum approach will assist clinicians to consider each individual's strengths and needs and personalise interventions and support accordingly. Profiling individual skills across these dimensions may also provide researchers with a greater capacity to link causal pathways with specific phenotypes, which is needed to develop precision medicine for autism.

Potential Sex Differences Relative to Autism Spectrum Disorder and Metals

PURPOSE OF REVIEW

This study aims to summarize the current body of literature on the relationship between various toxic metals exposures (i.e., aluminum, antimony, arsenic, beryllium, cadmium, chromium, lead, manganese, and nickel) and autism spectrum disorder (ASD), with a focus on potential sex differences in these associations.

RECENT FINDINGS

Sex differences in ASD diagnosis and mutagenic effects of toxic exposures indicate that sex differences may play a major part in the causal relationship of any potential associations seen; however, we were only able to find three studies that reported on sex differences in observed associations with toxic metals exposure and ASD. We also found several studies investigating associations between ASD and metals exposures, including 11 on aluminum, 6 on antimony, 15 on arsenic, 5 on beryllium, 17 on cadmium, 11 on chromium, 25 on lead, 14 on manganese, and 13 on nickel with markers of exposure in hair, urine, blood, teeth, fingernails, and air pollution. Results for each metal were conflicting, but studies on cadmium and lead yielded the highest proportion of studies with positive results (72% and 36%, respectively). Based on our examination of existing literature, the current evidence warrants a considerable need for evaluations of sex differences in future studies assessing the association between metals exposures and ASD. Additionally, failure to account for potential sex differences could result in bias and misinterpretation of exposure-disease relationships.

Psychiatric behaviors associated with cytoskeletal defects in radial neuronal migration

Normal development of the cerebral cortex is an important process for higher brain functions, such as language, and cognitive and social functions. Psychiatric disorders, such as schizophrenia and autism, are thought to develop owing to various dysfunctions occurring during the development of the cerebral cortex. Radial neuronal migration in the embryonic cerebral cortex is a complex process, which is achieved by strict control of cytoskeletal dynamics, and impairments in this process are suggested to cause various psychiatric disorders. Our recent findings indicate that radial neuronal migration as well as psychiatric behaviors is rescued by controlling microtubule stability during the embryonic stage. In this review, we outline the relationship between psychiatric disorders, such as schizophrenia and autism, and radial neuronal migration in the cerebral cortex by focusing on the cytoskeleton and centrosomes. New treatment strategies for psychiatric disorders will be discussed.