Attention-deficit/Hyperactivity Disorder in the context of Autism spectrum disorders

Transdiagnostic Attentional Deficits Are Associated with Depressive and Externalizing Symptoms in Children and Adolescents with Neuropsychiatric Disorders

OBJECTIVE

Although inattention, impulsivity, and impairments to vigilance are most associated with attention-deficit/hyperactivity disorder (ADHD), transdiagnostic attentional deficits are prevalent across all psychiatric disorders. To further elucidate this relationship, the present study investigated parent-reported neuropsychiatric symptom correlates of attention deficits using the factor structure of the Conners' Continuous Performance Test (CPT-II), a neuropsychological test of attention.

METHOD

Two-hundred and eighteen children and adolescents (7-21 years old) completed the CPT-II as part of standard clinical protocol during outpatient pediatric neuropsychology visits. The factor structure of the CPT-II was determined with a principal component analysis (PCA) using Promax rotation. Pearson correlation analyses and regression models examined the relationship between the generated factor structure, parent-reported clinical symptoms, and pre-determined clinical diagnoses.

RESULTS

Results from the PCA suggested a three-factor model best supported the structure of the CPT-II, and were subsequently defined as inattention, impulsivity, and vigilance. Performance-based inattention was significantly correlated with parent-reported hyperactivity, aggression, conduct problems, and depression. Parent-reported depressive symptoms and conduct problems were the strongest correlates of performance-based inattention, not hyperactivity or aggression. Performance-based inattention was significantly associated with an ADHD diagnosis but not a depression or anxiety diagnosis.

CONCLUSIONS

Findings suggest attentional deficits are not specific to any one disorder. To enhance the identification, classification, and treatment of neuropsychiatric disorders, both researchers and clinicians alike must diminish the importance of categorical approaches to child/adolescent psychopathology and continue to consider the dimensionality of transdiagnostic characteristics such as inattention.

Individual child factors affecting the diagnosis of attention deficit hyperactivity disorder (ADHD) in children and adolescents: a systematic review

Attention deficit hyperactivity disorder (ADHD) is a prevalent condition characterised by patterns of inattention, hyperactivity, and impulsivity. This systematic literature review aims to identify the child clinical and sociodemographic factors related to the detection and diagnosis of ADHD in children and adolescents, given concerns about delays or failures in identifying ADHD as well as over-diagnosis, hindering appropriate and timely support for children and families. Through electronic and manual searches of peer-reviewed and grey literature, 5852 articles were identified and subjected to two stages of screening by independent reviewers. Due to the heterogeneity in study methods, a narrative approach was used to summarise study findings. Forty-one studies meeting eligibility criteria revealed sixteen child-related factors influencing the ADHD diagnostic process. These factors include ADHD subtype, ADHD symptom severity, comorbid mental disorders, behavior problems, internalizing symptoms, functional impairment, social and cognitive functioning, physical health, gender, age, relative age, race/ethnicity, socio-economic status, insurance coverage, residence urbanicity, and family structure. While the impact of many of these factors on ADHD diagnosis was inconsistent due to the substantial diversity in study designs and context, certain patterns emerged. Meeting the criteria for the inattentive subtype, lower functional impairment, female gender, Black or Latinx ethnicity, and being relatively young for their grade were consistently found to be associated with a delayed or absent ADHD diagnosis. Further research is needed to explore the intricate relationships between these child-level variables and their implications for ADHD recognition, referral, and evaluation, especially outside the USA.

Neurexin1α knockout in rats causes aberrant social behaviour: relevance for autism and schizophrenia

RATIONALE

Genetic and environmental factors cause neuropsychiatric disorders through complex interactions that are far from understood. Loss-of-function mutations in synaptic proteins like neurexin1α have been linked to autism spectrum disorders (ASD) and schizophrenia (SCZ), both characterised by problems in social behaviour. Childhood social play behaviour is thought to facilitate social development, and lack of social play may precipitate or exacerbate ASD and SCZ.

OBJECTIVE

To test the hypothesis that an environmental insult acts on top of genetic vulnerability to precipitate psychiatric-like phenotypes. To that aim, social behaviour in neurexin1α knockout rats was assessed, with or without deprivation of juvenile social play. We also tested drugs prescribed in ASD or SCZ to assess the relevance of this dual-hit model for these disorders.

RESULTS

Neurexin1α knockout rats showed an aberrant social phenotype, with high amounts of social play, increased motivation to play, age-inappropriate sexual mounting, and an increase in general activity. Play deprivation subtly altered later social behaviour, but did not affect the phenotype of neurexin1α knockout rats. Risperidone and methylphenidate decreased play behaviour in both wild-type and knockout rats. Amphetamine-induced hyperactivity was exaggerated in neurexin1α knockout rats.

CONCLUSION

Deletion of the neurexin1α gene in rats causes exaggerated social play, which is not modified by social play deprivation. This phenotype therefore resembles disinhibited behaviour rather than the social withdrawal seen in ASD and SCZ. The neurexin1α knockout rat could be a model for inappropriate or disinhibited social behaviour seen in childhood mental disorders.

Automated Autism Assessment With Multimodal Data and Ensemble Learning: A Scalable and Consistent Robot-Enhanced Therapy Framework

Navigating the complexities of Autism Spectrum Disorder (ASD) diagnosis and intervention requires a nuanced approach that addresses both the inherent variability in therapeutic practices and the imperative for scalable solutions. This paper presents a transformative Robot-Enhanced Therapy (RET) framework, leveraging an intricate amalgamation of an Adaptive Boosted 3D biomarker approach and Saliency Maps generated through Kernel Density Estimation. By seamlessly integrating these methodologies through majority voting, the framework pioneers a new frontier in automating the assessment of ASD levels and Autism Diagnostic Observation Schedule (ADOS) scores, offering unprecedented precision and efficiency. Drawing upon the rich tapestry of the DREAM Dataset, encompassing data from 61 children, this study meticulously crafts novel features derived from diverse modalities including body skeleton, head movement, and eye gaze data. Our 3D bio-marker approach achieves a remarkable predictive prowess, boasting a staggering 95.59% accuracy and an F1 score of 92.75% for ASD level prediction, alongside an RMSE of 1.78 and an R-squared value of 0.74 for ADOS score prediction. Furthermore, the introduction of a pioneering saliency map generation method, harnessing gaze data, further enhances predictive models, elevating ASD level prediction accuracy to an impressive 97.36%, with a corresponding F1 score of 95.56%. Beyond technical achievements, this study underscores RET's transformative potential in reshaping ASD intervention paradigms, offering a promising alternative to Standard Human Therapy (SHT) by mitigating therapist variability and providing scalable therapeutic approaches. While acknowledging limitations in the research, such as sample constraints and model generalizability, our findings underscore RET's capacity to revolutionize ASD management.

Developing a therapeutic app based on the emotional Stroop task for objective discovery of daily life issues for people with ADHD

Pinpointing the most urgent problem to start treatment on in therapy for people with ADHD is a subjective and time-consuming process. To improve this process, we designed a proof-of-concept for an application that can identify daily life issues that cause negative mental load. Through several modified emotional Stroop-tasks, we show that people with ADHD respond slower to negative emotions and daily life issues related to ADHD, compared to neurotypicals. Negative emotions and social issues were especially prevalent in the ADHD participants. The application highlighted two to five issues per participant. This could indicate that these topics cause the highest mental load in the participant, and need attention first from a therapist. Using this application in a therapeutic context could deliver a more objective, personalized, traceable and efficient therapy for daily-life issues in ADHD.

Assessing visual motor performance in autistic children based on Kinect and fNIRS: A case study

In recent years, the incidence rate of children with autism has shown a significant upward trend. Rehabilitation training is an important part of recovery or improvement in autism children. However, during autism rehabilitation training, the methods that can visually reflect and objectively evaluate its effects are seldom considered. Therefore, this study aimed to objectively evaluate the rehabilitation impact of visual-motor skills training in children with autism via quantitative measures. In this study, vision sensors and functional near-infrared spectroscopy were used to monitor and analyze visual motor training task of 20 autism children. These children were divided into high- and low-score groups according to the autism behavior checklist (ABC). Results showed significant differences between the high- and low-score groups in the brain regions of the left and right temporal lobe, right motor cortex, and left occipital lobe; the difference in functional connectivity was greatest when the left hand was moving at the green light (p < 0.05). The differences in speed, acceleration, and angle between the high- and low-score groups were mainly reflected in left-hand movement. Moreover, analysis of multimodal data showed that visual motor training had a positive effect on brain activation and functional connectivity, and increasing the frequency of left-hand training and using more green light were beneficial to the improvement of brain function. These findings can be used as basis to help optimize rehabilitation programs and improve rehabilitation effectiveness.

Histidine-containing dipeptide deficiency links to hyperactivity and depression-like behaviors in old female mice

Carnosine, anserine, and homocarnosine are histidine-containing dipeptides (HCDs) abundant in the skeletal muscle and nervous system in mammals. To date, studies have extensively demonstrated effects of carnosine and anserine, the predominant muscular HCDs, on muscular functions and exercise performance. However, homocarnosine, the predominant brain HCD, is underexplored. Moreover, roles of homocarnosine and its related HCDs in the brain and behaviors remain poorly understood. Here, we investigated potential roles of endogenous brain homocarnosine and its related HCDs in behaviors by using carnosine synthase-1-deficient (Carns1-/-) mice. We found that old Carns1-/- mice (female 12 months old) exhibited hyperactivity- and depression-like behaviors with higher plasma corticosterone levels on light-dark transition and forced swimming tests, but had no defects in spontaneous locomotor activity, repetitive behavior, olfactory functions, and learning and memory abilities, as compared with their age-matched wild-type (WT) mice. We confirmed that homocarnosine and its related HCDs were deficient across brain areas of Carns1-/- mice. Homocarnosine deficiency exhibited small effects on its constituent γ-aminobutyric acid (GABA) in the brain, in which GABA levels in hypothalamus and olfactory bulb were higher in Carns1-/- mice than in WT mice. In WT mice, homocarnosine and GABA were highly present in hypothalamus, thalamus, and olfactory bulb, and their brain levels did not decrease in old mice when compared with younger mice (3 months old). Our present findings provide new insights into roles of homocarnosine and its related HCDs in behaviors and neurological disorders.

Electrical Synapses Mediate Embryonic Hyperactivity in a Zebrafish Model of Fragile X Syndrome

Although hyperactivity is associated with a wide variety of neurodevelopmental disorders, the early embryonic origins of locomotion have hindered investigation of pathogenesis of these debilitating behaviors. The earliest motor output in vertebrate animals is generated by clusters of early-born motor neurons (MNs) that occupy distinct regions of the spinal cord, innervating stereotyped muscle groups. Gap junction electrical synapses drive early spontaneous behavior in zebrafish, prior to the emergence of chemical neurotransmitter networks. We use a genetic model of hyperactivity to gain critical insight into the consequences of errors in motor circuit formation and function, finding that Fragile X syndrome model mutant zebrafish are hyperexcitable from the earliest phases of spontaneous behavior, show altered sensitivity to blockade of electrical gap junctions, and have increased expression of the gap junction protein Connexin 34/35. We further show that this hyperexcitable behavior can be rescued by pharmacological inhibition of electrical synapses. We also use functional imaging to examine MN and interneuron (IN) activity in early embryogenesis, finding genetic disruption of electrical gap junctions uncouples activity between mnx1 + MNs and INs. Taken together, our work highlights the importance of electrical synapses in motor development and suggests that the origins of hyperactivity in neurodevelopmental disorders may be established during the initial formation of locomotive circuits.

Examining the feasibility and utility of heart rate variability on intervention outcomes targeting emotion regulation in autism: a brief report

Autistic youth experience several behavioral and emotional characteristics that can predispose them to emotion dysregulation (ED). Current literature examining ED in autism spectrum disorder (ASD) is limited to parent- and self-reported measures, indicating a need for biological or physiological methods to better assess emotion regulation in ASD. Utilizing the autonomic nervous system, specifically heart rate variability (HRV), may be a promising method to objectively measure ED in ASD, given it is one of the body's primary means of regulating physiological arousal. Our pilot study is one of the first to examine the feasibility, utility, and construct validity of HRV along with clinical measures within an intervention targeting ED-specific symptoms in ASD. Participants included 30 autistic youth ages 8-17 years who participated in the pilot study of Regulating Together, a group-based intervention targeting emotion regulation. We demonstrate HRV is feasible, demonstrates adequate test-retest reliability, and is complimentary to clinician- and parent-reported measures. Our preliminary findings also point to certain HRV profiles being indicative of long-term outcomes after receiving treatment. HRV may be a useful, objective tool in determining differential needs of long-term follow-up care for treatment maintenance at screening or baseline stages.

The Impact of Co-occurring ADHD on Social Competence Intervention Outcomes in Youth with Autism Spectrum Disorder

PURPOSE

The co-occurrence of autism spectrum disorder (ASD) and attention- deficit/hyperactivity disorder (ADHD) is significant and associated with a host of negative outcomes. Studies investigating social functioning in the presence of the ASD/ADHD co-occurrence have produced mixed findings. The present study further evaluated the impact of co-occurring ADHD on social functioning among youth with ASD and compared treatment response to a social competence intervention between youth with ASD and ASD + ADHD.

METHODS

Two-way repeated measures analyses of variance (ANOVAs) were computed with diagnostic group and time as the independent variables and measures of social functioning as dependent variables. Group and Time effects and Group by Time interactions were examined.

RESULTS

Youth with co-occurring ADHD displayed more impairments related to social awareness, but not in other social areas. Participants in both the ASD and ASD + ADHD groups demonstrated significant improvement following a social competence intervention.

CONCLUSION

Co-occurring ADHD did not negatively affect treatment response. Youth with ASD + ADHD may benefit highly structured interventions with a scaffolded teaching design.

Motor competence is related to acquisition of error-based but not reinforcement learning in children ages 6 to 12

Background

An essential component of childhood development is increasing motor competence. Poor motor learning is often thought to underlie impaired motor competence, but this link is unclear in previous studies.

Aims

Our aim was to test the relationship between motor competence and motor learning in the acquisition phase. Both reinforcement learning (RL) and error-based learning (EBL) were tested. We hypothesized that slower RL and slower EBL acquisition rates would relate to lower motor competence.

Methods and procedures

Eighty-six participants ages 6-12 performed a target throwing task under RL and EBL conditions. The Movement Assessment Battery for Children - 2nd edition (MABC-2) provided a measure of motor competence. We assessed EBL and RL acquisition rates, baseline variability, and baseline bias from the throwing task.

Outcomes and results

In a multiple linear regression model, baseline variability (β = -0.49, p = <0.001) and the EBL acquisition rate (β = -0.24, p = 0.018) significantly explained the MABC-2 score. Participants with higher baseline variability and slower EBL acquisition had lower motor competence scores. The RL acquisition rate was independent of MABC-2 score suggesting that RL may be less of a contributor to poor motor competence.

Conclusions and implications

Children with slower EBL acquisition had lower motor competence scores but RL acquisition was unrelated to the level of motor competence. Emphasizing the unrelated reinforcement mechanisms over error-based mechanisms during motor skill interventions may help children with poor motor competence better acquire new motor skills.

Practice is the best of all instructors-Effects of enactment encoding and episodic future thinking on prospective memory performance in high-functioning adults with autism spectrum disorder

Prospective memory (PM) is the ability to remember to carry out intended actions in the future. The present study investigated the effects of episodic future thinking (EFT) and enactment encoding (EE) on PM performance in autistic adults (ASD). A total of 72 autistic individuals and 70 controls matched for age, gender, and cognitive abilities completed a computerized version of the Dresden breakfast Task, which required participants to prepare breakfast following a set of rules and time restrictions. A two (group: ASD vs. controls) by three (encoding condition: EFT vs. EE vs. standard) between-subjects design was applied. Participants were either instructed to engage in EFT or EE to prepare to the different tasks prior to performing the Dresden breakfast or received standard instructions. Analyses of variance were conducted. Autism-spectrum-disorders (ASD) participants did not differ from control participants in their PM performance, regardless of which strategy they used. Compared to the standard condition, EE but not EFT improved time-based PM performance in all participants. This is the first study to find spared time-based PM performance in autistic individuals. The results confirm earlier results of beneficial effects of EE on PM performance. Findings are discussed with regards to the methodology used, sample composition as well as autistic characteristics.

Amygdalar neurotransmission alterations in the BTBR mice model of idiopathic autism

Autism Spectrum Disorders (ASD) are principally diagnosed by three core behavioural symptoms, such as stereotyped repertoire, communication impairments and social dysfunctions. This complex pathology has been linked to abnormalities of corticostriatal and limbic circuits. Despite experimental efforts in elucidating the molecular mechanisms behind these abnormalities, a clear etiopathogenic hypothesis is still lacking. To this aim, preclinical studies can be really helpful to longitudinally study behavioural alterations resembling human symptoms and to investigate the underlying neurobiological correlates. In this regard, the BTBR T+ Itpr3tf/J (BTBR) mice are an inbred mouse strain that exhibits a pattern of behaviours well resembling human ASD-like behavioural features. In this study, the BTBR mice model was used to investigate neurochemical and biomolecular alterations, regarding Nerve Growth Factor (NGF) and Brain-Derived Neurotrophic Factor (BDNF), together with GABAergic, glutamatergic, cholinergic, dopaminergic and noradrenergic neurotransmissions and their metabolites in four different brain areas, i.e. prefrontal cortex, hippocampus, amygdala and hypothalamus. In our results, BTBR strain reported decreased noradrenaline, acetylcholine and GABA levels in prefrontal cortex, while hippocampal measurements showed reduced NGF and BDNF expression levels, together with GABA levels. Concerning hypothalamus, no differences were retrieved. As regarding amygdala, we found reduced dopamine levels, accompanied by increased dopamine metabolites in BTBR mice, together with decreased acetylcholine, NGF and GABA levels and enhanced glutamate content. Taken together, our data showed that the BTBR ASD model, beyond its face validity, is a useful tool to untangle neurotransmission alterations that could be underpinned to the heterogeneous ASD-like behaviours, highlighting the crucial role played by amygdala.

The Exon Junction Complex Factor RBM8A in Glial Fibrillary Acid Protein-Expressing Astrocytes Modulates Locomotion Behaviors

The role of RNA Binding Motif Protein 8a (RBM8A), an exon junction complex (EJC) component, in neurodevelopmental disorders has been increasingly studied for its crucial role in regulating multiple levels of gene expression. It regulates mRNA splicing, translation, and mRNA degradation and influences embryonic development. RBM8A protein is expressed in both neurons and astrocytes, but little is known about RBM8A's specific role in glial fibrillary acid protein (GFAP)-positive astrocytes. To address the role of RBM8A in astrocytes, we generated a conditional heterozygous knockout (KO) mouse line of Rbm8a in astrocytes using a GFAP-cre line. We confirmed a decreased expression of RBM8A in astrocytes of heterozygous conditional KO mice via RT-PCR and Sanger sequencing, as well as qRT-PCR, immunohistochemistry, and Western blot. Interestingly, these mice exhibit significantly increased movement and mobility, alongside sex-specific altered anxiety in the open field test (OFT) and elevated plus maze (OPM) tests. These tests, along with the rotarod test, suggest that these mice have normal motor coordination but hyperactive phenotypes. In addition, the haploinsufficiency of Rbm8a in astrocytes leads to a sex-specific change in astrocyte density in the dentate gyrus. This study further reveals the contribution of Rbm8a deletion to CNS pathology, generating more insights via the glial lens of an Rbm8a model of neurodevelopmental disorder.

Associations Between Coordination and Wearable Sensor Variables Vary by Recording Context but Not Assessment Type

Motor coordination is an important driver of development and improved coordination assessments could facilitate better screening, diagnosis, and intervention for children at risk of developmental disorders. Wearable sensors could provide data that enhance the characterization of coordination and the clinical utility of that data may vary depending on how sensor variables from different recording contexts relate to coordination. We used wearable sensors at the wrists to capture upper-limb movement in 85 children aged 6-12. Sensor variables were extracted from two recording contexts. Structured recordings occurred in the lab during a unilateral throwing task. Unstructured recordings occurred during free-living activity. The objective was to determine the influence of recording context (unstructured versus structured) and assessment type (direct vs. indirect) on the association between sensor variables and coordination. The greatest associations were between six sensor variables from the structured context and the direct measure of coordination. Worse coordination scores were associated with upper-limb movements that had higher peak magnitudes, greater variance, and less smoothness. The associations were consistent across both arms, even though the structured task was unilateral. This finding suggests that wearable sensors could be paired with a simple, structured task to yield clinically informative variables that relate to motor coordination.

Predictors of Autism Spectrum Disorder and ADHD: Results from the National Survey of Children's Health

BACKGROUND

Autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD) are two of the most common neurodevelopmental disorders with comorbidity rates of up to 70%. Population-based studies show differential rates of ADHD and ASD diagnosis based on sociodemographic variables. However, no studies to date have examined the role of sociodemographic factors on the likelihood of receiving an ADHD, ASD, or comorbid ASD + ADHD diagnosis in a large, nationally representative sample.

OBJECTIVE

This study aims to examine the impact of sociodemographic factors on the odds of experiencing ASD-only, ADHD-only, or both diagnoses for children in the United States.

METHODS

Using a mixed effects multinomial logistic modeling approach and data from the 2016-2018 National Survey of Children's Health, we estimated the association between sociodemographic variables and the log odds of being in each diagnostic group.

RESULTS

Sociodemographic variables were differentially related to the three diagnostic groups: ASD-only, ADHD-only, and ASD + ADHD. Compared to girls, boys experienced higher odds of all three diagnosis categories. White children had higher odds of having an ADHD-only or ASD + ADHD diagnosis compared to non-Hispanic (NH) Black, NH multiple/other race, and Hispanic children. Odds ratios for levels of parent education, household income, and birth characteristics showed varying trends across diagnostic groups.

CONCLUSIONS

Overall, our findings point to unique sets of risk factors differentially associated ASD and ADHD, with lower income standing out as an important factor associated with receiving a diagnosis of ASD + ADHD.

Multi-level and joint attention networks on brain functional connectivity for cross-cognitive prediction

Deep learning on resting-state functional MRI (rs-fMRI) has shown great success in predicting a single cognition or mental disease. Nevertheless, cognitive functions or mental diseases may share neural mechanisms that can benefit their prediction/classification. We propose a multi-level and joint attention (ML-Joint-Att) network to learn high-order representations of brain functional connectivities that are specific and shared across multiple tasks. We design the ML-Joint-Att network with edge and node convolutional operators, an adaptive inception module, and three attention modules, including network-wise, region-wise, and region-wise joint attention modules. The adaptive inception learns brain functional connectivity at multiple spatial scales. The network-wise and region-wise attention modules take the multi-scale functional connectivities as input and learn features at the network and regional levels for individual tasks. Moreover, the joint attention module is designed as region-wise joint attention to learn shared brain features that contribute to and compensate for the prediction of multiple tasks. We employed the Adolescent Brain Cognitive Development (ABCD) dataset (n =9092) to evaluate the ML-Joint-Att network for the prediction of cognitive flexibility and inhibition. Our experiments demonstrated the usefulness of the three attention modules and identified brain functional connectivities and regions specific and common between cognitive flexibility and inhibition. In particular, the joint attention module can significantly improve the prediction of both cognitive functions. Moreover, leave-one-site cross-validation showed that the ML-Joint-Att network is robust to independent samples obtained from different sites of the ABCD study. Our network outperformed existing machine learning techniques, including Brain Bias Set (BBS), spatio-temporal graph convolution network (ST-GCN), and BrainNetCNN. We demonstrated the generalization of our method to other applications, such as the prediction of fluid intelligence and crystallized intelligence, which also outperformed the ST-GCN and BrainNetCNN.

Rhythmic attentional sampling in autism

Individuals diagnosed with autism often display alterations in visual spatial attention toward visual stimuli, but the underlying cause of these differences remains unclear. Recent evidence has demonstrated that covert spatial attention, rather than remaining constant at a cued location, samples stimuli rhythmically at a frequency of 4-8 Hz (theta). Here we tested whether rhythmic sampling of attention is altered in autism. Participants were asked to monitor three locations to detect a brief target presented 300-1200 ms after a spatial cue. Visual attention was oriented to the cue and modified visual processing at the cued location, consistent with previous studies. We measured detection performance at different cue-target intervals when the target occurred at the cued location. Significant oscillations in detection performance were identified using both a traditional time-shuffled approach and a new autoregressive surrogate method developed by Brookshire in 2022. We found that attention enhances behavioral performance rhythmically at the same frequency in both autism and control group at the cued location. However, rhythmic temporal structure was not observed in a subgroup of autistic individuals with co-occurring attention-deficit/hyperactivity disorder (ADHD). Our results imply that intrinsic brain rhythms which organize neural activity into alternating attentional states is functional in autistic individuals, but may be altered in autistic participants who have a concurrent ADHD diagnosis.

Interaction of Heavy Metal Lead with Gut Microbiota: Implications for Autism Spectrum Disorder

Autism Spectrum Disorder (ASD), a neurodevelopmental disorder characterized by persistent deficits in social interaction and communication, manifests in early childhood and is followed by restricted and stereotyped behaviors, interests, or activities in adolescence and adulthood (DSM-V). Although genetics and environmental factors have been implicated, the exact causes of ASD have yet to be fully characterized. New evidence suggests that dysbiosis or perturbation in gut microbiota (GM) and exposure to lead (Pb) may play important roles in ASD etiology. Pb is a toxic heavy metal that has been linked to a wide range of negative health outcomes, including anemia, encephalopathy, gastroenteric diseases, and, more importantly, cognitive and behavioral problems inherent to ASD. Pb exposure can disrupt GM, which is essential for maintaining overall health. GM, consisting of trillions of microorganisms, has been shown to play a crucial role in the development of various physiological and psychological functions. GM interacts with the brain in a bidirectional manner referred to as the "Gut-Brain Axis (GBA)". In this review, following a general overview of ASD and GM, the interaction of Pb with GM in the context of ASD is emphasized. The potential exploitation of this interaction for therapeutic purposes is also touched upon.

Pharmacotherapy in autism spectrum disorders, including promising older drugs warranting trials

Available pharmacotherapies for autism spectrum disorders (ASD) are reviewed based on clinical and research experience, highlighting some older drugs with emerging evidence. Several medications show efficacy in ASD, though controlled studies in ASD are largely lacking. Only risperidone and aripiprazole have Federal Drug Administration approval in the United States. Methylphenidate (MPH) studies showed lower efficacy and tolerability for attention deficit hyperactivity disorder (ADHD) than in the typically developing (TD) population; atomoxetine demonstrated lower efficacy but comparable tolerability to TD outcomes. Guanfacine improved hyperactivity in ASD comparably to TD. Dex-troamphetamine promises greater efficacy than MPH in ASD. ADHD medications reduce impulsive aggression in youth, and may also be key for this in adults. Controlled trials of the selective serotonin reuptake inhibitors citalopram and fluoxetine demonstrated poor tolerability and lack of efficacy for repetitive behaviors. Trials of antiseizure medications in ASD remain inconclusive, however clinical trials may be warranted in severely disabled individuals showing bizarre behaviors. No identified drugs treat ASD core symptoms; oxytocin lacked efficacy. Amitriptyline and loxapine however, show promise. Loxapine at 5-10 mg daily resembled an atypical antipsychotic in positron emission tomography studies, but may be weight-sparing. Amitriptyline at approximately 1 mg/ kg/day used cautiously, shows efficacy for sleep, anxiety, impulsivity and ADHD, repetitive behaviors, and enuresis. Both drugs have promising neurotrophic properties.

Regulating Together: Emotion Dysregulation Group Treatment for ASD Youth and Their Caregivers

Individuals with autism spectrum disorder (ASD) experience behavioral and emotional symptoms hypothesized to arise from emotion dysregulation (ED), difficulty modulating emotional experience, expression, and intensity in an acceptable and contextually appropriate manner. We developed Regulating Together (RT)-an intensive-outpatient, caregiver-assisted group program to meet the ASD + ED intervention critical need. A within-subjects trial was conducted (5-week-control lead-in period, 5-week-treatment, and 5-and 10-weeks-post-treatment follow-ups). Forty-four youth with ASD + ED (25 8-12, 19 13-18 yr-olds, 88% male, mean FSIQ of 96) participated. Improvements were found in reactivity, emotion regulation knowledge, and flexibility post-treatment and 10-weeks post-treatment. A reduction in inpatient hospitalization rates by 16% from the 12 months pre-RT to 12 months post-RT was observed. RT shows promise to reduce ED in ASD.

Patterns of sensory processing in young children with autism: Differences in autism characteristics, adaptive skills, and attentional problems

LAY ABSTRACT

Research has found differences in responding to various sensory stimuli among autistic individuals, which are associated with social and adaptive skills. However, our understanding of sensory profiles in autism has been complicated due to the variable presentation of sensory symptoms. One way to better understand variability in sensory symptoms is to use advanced statistical approaches, such as latent profile analysis, that allow for the identification of more similar sensory classes in otherwise variable groups. We used the Short Sensory Profile to identify homogeneous classes of sensory reactivity in autistic children based on both severity and modality and examined whether sensory classes differed in terms of autism characteristics, adaptive skills, and attention-deficit/hyperactivity disorder symptoms. Based on the pattern of both severity and modality, four sensory classes emerged and were named Moderate/Mixed (35.5%; probable-to-definite differences in all modalities except in movement sensitivity and low energy/weakness), Severe/Mixed (8.5%; definite sensory differences in all modalities except in low energy/weakness), Moderate/Broad (14.6%; probable-to-definite differences in all modalities), and Low/Mixed (41.1%; typical scores in most modalities with probable differences in taste/smell sensitivity, under-responsive/seeks sensation, and auditory filtering). The Severe/Mixed class exhibited greater problems in a variety of areas such as social, adaptive, and attention-deficit/hyperactivity disorder symptoms, whereas the Low/Mixed class showed overall fewer problems. This may provide insight for clinicians and researchers aiming to understand whether autistic children who exhibit distinct sensory patterns are more or less likely to also experience social, adaptive, and/or attention/behavior-related difficulties.

Evaluating the effect of R-Baclofen and LP-211 on autistic behavior of the BTBR and Fmr1-KO mouse models

Introduction

Autism spectrum disorder (ASD) is a persistent neurodevelopmental condition characterized by two core behavioral symptoms: impaired social communication and interaction, as well as stereotypic, repetitive behavior. No distinct cause of ASD is known so far; however, excitatory/inhibitory imbalance and a disturbed serotoninergic transmission have been identified as prominent candidates responsible for ASD etiology.

Methods

The GABAB receptor agonist R-Baclofen and the selective agonist for the 5HT7 serotonin receptor LP-211 have been reported to correct social deficits and repetitive behaviors in mouse models of ASD. To evaluate the efficacy of these compounds in more details, we treated BTBR T+ Itpr3tf/J and B6.129P2-Fmr1tm1Cgr/J mice acutely with R-Baclofen or LP-211 and evaluated the behavior of animals in a series of tests.

Results

BTBR mice showed motor deficits, elevated anxiety, and highly repetitive behavior of self-grooming. Fmr1-KO mice exhibited decreased anxiety and hyperactivity. Additionally, Fmr1-KO mice’s ultrasonic vocalizations were impaired suggesting a reduced social interest and communication of this strain. Acute LP-211 administration did not affect the behavioral abnormalities observed in BTBR mice but improved repetitive behavior in Fmr1-KO mice and showed a trend to change anxiety of this strain. Acute R-Baclofen treatment improved repetitive behavior only in Fmr1-KO mice.

Conclusion

Our results add value to the current available data on these mouse models and the respective compounds. Yet, additional studies are needed to further test R-Baclofen and LP-211 as potential treatments for ASD therapy.

Face processing in young adults with autism and ADHD: An event related potentials study

Background

Atypicalities in perception and interpretation of faces and emotional facial expressions have been reported in both autism and attention-deficit/hyperactivity disorder (ADHD) during childhood and adulthood. Investigation of face processing during young adulthood (18 to 25 years), a transition period to full-fledged adulthood, could provide important information on the adult outcomes of autism and ADHD.

Methods

In this study, we investigated event-related potentials (ERPs) related to visual face processing in autism, ADHD, and co-occurring autism and ADHD in a large sample of young adults (N = 566). The groups were based on the Diagnostic Interview for ADHD in Adults 2.0 (DIVA-2) and the Autism Diagnostic Observation Schedule-2 (ADOS-2). We analyzed ERPs from two passive viewing tasks previously used in childhood investigations: (1) upright and inverted faces with direct or averted gaze; (2) faces expressing different emotions.

Results

Across both tasks, we consistently found lower amplitude and longer latency of N170 in participants with autism compared to those without. Longer P1 latencies and smaller P3 amplitudes in response to emotional expressions and longer P3 latencies for upright faces were also characteristic to the autistic group. Those with ADHD had longer N170 latencies, specific to the face-gaze task. Individuals with both autism and ADHD showed additional alterations in gaze modulation and a lack of the face inversion effect indexed by a delayed N170.

Conclusion

Alterations in N170 for autistic young adults is largely consistent with studies on autistic adults, and some studies in autistic children. These findings suggest that there are identifiable and measurable socio-functional atypicalities in young adults with autism.

Identifying activity level related movement features of children with ASD based on ADOS videos

Autism spectrum disorder (ASD) is a neurodevelopmental disorder that affects about 2% of children. Due to the shortage of clinicians, there is an urgent demand for a convenient and effective tool based on regular videos to assess the symptom. Computer-aided technologies have become widely used in clinical diagnosis, simplifying the diagnosis process while saving time and standardizing the procedure. In this study, we proposed a computer vision-based motion trajectory detection approach assisted with machine learning techniques, facilitating an objective and effective way to extract participants' movement features (MFs) to identify and evaluate children's activity levels that correspond to clinicians' professional ratings. The designed technique includes two key parts: (1) Extracting MFs of participants' different body key points in various activities segmented from autism diagnostic observation schedule (ADOS) videos, and (2) Identifying the most relevant MFs through established correlations with existing data sets of participants' activity level scores evaluated by clinicians. The research investigated two types of MFs, i.e., pixel distance (PD) and instantaneous pixel velocity (IPV), three participants' body key points, i.e., neck, right wrist, and middle hip, and five activities, including Table-play, Birthday-party, Joint-attention, Balloon-play, and Bubble-play segmented from ADOS videos. Among different combinations, the high correlations with the activity level scores evaluated by the clinicians (greater than 0.6 with p < 0.001) were found in Table-play activity for both the PD-based MFs of all three studied key points and the IPV-based MFs of the right wrist key point. These MFs were identified as the most relevant ones that could be utilized as an auxiliary means for automating the evaluation of activity levels in the ASD assessment.

Catecholaminergic and cholinergic neuromodulation in autism spectrum disorder: A comparison to attention-deficit hyperactivity disorder

Autism spectrum disorder (ASD) is a heterogeneous neurodevelopmental disorder characterized by social impairments and restricted, repetitive behaviors. Treatment of ASD is notoriously difficult and might benefit from identification of underlying mechanisms that overlap with those disturbed in other developmental disorders, for which treatment options are more obvious. One example of the latter is attention-deficit hyperactivity disorder (ADHD), given the efficacy of especially stimulants in treatment of ADHD. Deficiencies in catecholaminergic systems [dopamine (DA), norepinephrine (NE)] in ADHD are obvious targets for stimulant treatment. Recent findings suggest that dysfunction in catecholaminergic systems may also be a factor in at least a subgroup of ASD. In this review we scrutinize the evidence for catecholaminergic mechanisms underlying ASD symptoms, and also include in this analysis a third classic ascending arousing system, the acetylcholinergic (ACh) network. We complement this with a comprehensive review of DA-, NE-, and ACh-targeted interventions in ASD, and an exploratory search for potential treatment-response predictors (biomarkers) in ASD, genetically or otherwise. Based on this review and analysis we propose that (1) stimulant treatment may be a viable option for an ASD subcategory, possibly defined by genetic subtyping; (2) cerebellar dysfunction is pronounced for a relatively small ADHD subgroup but much more common in ASD and in both cases may point toward NE- or ACh-directed intervention; (3) deficiency of the cortical salience network is sizable in subgroups of both disorders, and biomarkers such as eye blink rate and pupillometric data may predict the efficacy of targeting this underlying deficiency via DA, NE, or ACh in both ASD and ADHD.

Important Preliminary Insights for Designing Successful Communication between a Robotic Learning Assistant and Children with Autism Spectrum Disorder in Germany

Early therapeutic intervention programs help children diagnosed with Autism Spectrum Disorder (ASD) to improve their socio-emotional and functional skills. To relieve the children’s caregivers while ensuring that the children are adequately supported in their training exercises, new technologies may offer suitable solutions. This study investigates the potential of a robotic learning assistant which is planned to monitor the children’s state of engagement and to intervene with appropriate motivational nudges when necessary. To analyze stakeholder requirements, interviews with parents as well as therapists of children with ASD were conducted. Besides a general positive attitude towards the usage of new technologies, we received some important insights for the design of the robot and its interaction with the children. One strongly accentuated aspect was the robot’s adequate and context-specific communication behavior, which we plan to address via an AI-based engagement detection system. Further aspects comprise for instance customizability, adaptability, and variability of the robot’s behavior, which should further be not too distracting while still being highly predictable.

A Feasibility Study of Bilateral Wrist Sensors for Measuring Motor Traits in Children With Autism

Direct, quantitative measures of hyperactivity and motor coordination, two motor characteristics associated with impairment in autism, are limited. Wearable sensors can objectively index real-world movement variables that may relate to these behaviors. Here, we explored the feasibility of bilateral wrist accelerometers for measuring upper limb activity in 3-10-year-olds with autism (n = 22; 19 boys, 3 girls; M age = 5.64, SD = 2.73 years) and without autism (n = 26; 15 boys, 11 girls; M age = 6.26, SD = 2.47 years). We investigated the relationships between movement characteristics related to duration, intensity, complexity, and symmetry on the one hand and parent-reported hyperactivity and motor coordination on the other. Participants with and without autism wore the sensors for 12-hour periods. Sensor variables varied by age but not sex, with movement intensity and complexity moderately related to motor coordination. These findings lend preliminary support to wearable sensors as a means of providing ecologically-valid metrics of motor characteristics that impact adaptive function in children with autism.

The utility of the autism-spectrum quotient to screen for autism spectrum disorder in adults with attention deficit/hyperactivity disorder

The co-occurrence of attention deficit/hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) has been reported to be highly prevalent in adults. However, very few studies have assessed the usefulness of screening instruments to detect this co-occurrence, particularly when screening for ASD in the context of ADHD. Our study aimed at assessing the utility of the autism-spectrum quotient (AQ) as a screening tool of ASD in a sample of 153 adults referred for ADHD assessment. Our results showed that the AQ is of limited use in this context as its positive predictive value was low (47%). Particularly, the more severe the attentional deficits the more likely individuals with ADHD were to be misclassified as having a co-occurring ASD based on the AQ. However, the "imagination" subscale of the AQ was able to discriminate those who met ASD criteria from those who did not, suggesting that targeting imagination impairments might be useful when assessing for the ADHD+ASD co-occurrence in clinical settings.

Cognitive and behavioral profiles in children with autism spectrum disorder with and without Attention-Deficit/hyperactivity disorder

BACKGROUND

Understanding the developmental trajectories of children with autism spectrum disorder (ASD) with and without comorbid ADHD is relevant to tailor care plans. This prospective study assessed, for the first time, cognitive, emotional, behavioral, and learning outcomes in adolescence of children with ASD-ADHD and in those with ASD+ADHD in childhood. Possible predictors of severity of ASD core symptoms in adolescence were also evaluated.

METHODS

Forty-five adolescents without intellectual disability, 26 diagnosed in childhood with ASD-ADHD and 19 with ASD+ADHD, were evaluated at baseline (mean age: 8.6 ± 1.3) and at 5-year follow-up (mean age: 12.9 ± 0.9). Parents and teachers completed questionnaires on executive functions, theory of mind (ToM), emotional/behavioral difficulties (EBD), and learning style at both time points..

RESULTS

Overall different developmental trajectories for the two groups were found. In general, deficits in metacognition processes, ToM skills, EBD, and learning abilities were more pronounced in the ASD+ group. Over time, the ASD+ADHD group, but not the ASD-ADHD, tended to improve in EBD and metacognition but their level of development continued to be lower compared with ASD+ADHD. EBD in childhood were significant predictors of autism core symptoms of adolescents.

CONCLUSIONS

Our findings highlight the importance of an early identification of comorbid ADHD symptoms in ASD to offer treatment strategies based on specific developmental trajectories.

ASD symptoms in adults with ADHD: a preliminary study using the ADOS-2

Attention-deficit/hyperactivity disorder (ADHD) has long been regarded as disparate and mutually exclusive to autism spectrum disorder (ASD) in the Diagnostic and Statistical Manual of Mental Disorders (DSM)-III-R and DSM-IV. However, this idea has become obsolete due to a growing body of evidence suggesting numerous phenotypic and genetic similarities between ADHD and ASD. ASD symptoms or autistic traits in individuals with ADHD have been examined; however, most studies were conducted on children and relied on self- or parent- reports. ASD symptoms assessed with more direct, objective measures, such as the Autism Diagnostic Observation Schedule, Second Edition (ADOS-2) in adults with ADHD, remain understudied. In the present study, we used the ADOS-2 to evaluate ASD symptoms in adults with ADHD who were not clinically diagnosed with ASD. Fifty-six adults (mean age 33.9 years, 35 males, intelligence quotient ≥ 85), who were diagnosed with ADHD based on the DSM-5 criteria, completed Module 4 of the ADOS-2. Autism Spectrum Quotient (AQ), Conners' Adult ADHD Rating Scale (CAARS), and Wechsler Adult Intelligence Scale (WAIS)-III were also administered to assess self-rated ASD symptoms, ADHD symptoms, and intelligence, respectively. Overall, 23.3% of participants met the ASD diagnostic classification on the ADOS-2. Social reciprocal interaction scores tended to be higher, while restricted and repetitive behavior scores were low. The scoring patterns and possible overlapping and differing phenotypic characteristics of ADHD and ASD are discussed.

Association of maternal diabetes with neurodevelopmental disorders: autism spectrum disorders, attention-deficit/hyperactivity disorder and intellectual disability

Background

Maternal diabetes has been associated with a risk of neurodevelopmental disorders (NDDs) in offspring, though the common co-occurrence of autism spectrum disorders (ASD), attention-deficit/hyperactivity disorder (ADHD) and intellectual disability (ID) is rarely considered, nor is the potential for confounding by shared familial factors (e.g. genetics).

Methods

This population-based cohort study used data from Psychiatry Sweden, a linkage of Swedish national registers, to follow 2 369 680 individuals born from 1987 to 2010. We used population-averaged logit models to examine the association between exposure to maternal type 1 diabetes mellitus (T1DM), pre-gestational type 2 diabetes mellitus (T2DM) or gestational diabetes mellitus (GDM), and odds of NDDs in offspring. Subgroup analysis was then performed to investigate the timings of GDM diagnosis during pregnancy and its effect on the odds of NDDs in offspring. We compared these results to models considering paternal lifetime T1DM and T2DM as exposures.

Results

Overall, 45 678 individuals (1.93%) were diagnosed with ASD, 20 823 (0.88%) with ID and 102 018 (4.31%) with ADHD. All types of maternal diabetes were associated with odds of NDDs, with T2DM most strongly associated with any diagnosis of ASD (odds ratio_adjusted 1.37, 95% confidence interval 1.03–1.84), ID (2.09, 1.53–2.87) and ADHD (1.43, 1.16–1.77). Considering common co-morbid groups, the associations were strongest between maternal diabetes and diagnostic combinations that included ID. Paternal T1DM and T2DM diagnoses were also associated with offspring NDDs, but these associations were weaker than those with maternal diabetes. Diagnosis of GDM between 27 and 30 weeks of gestation was generally associated with the greatest risk of NDDs in offspring, with the strongest associations for outcomes that included ID.

Conclusion

The association of maternal diabetes with NDDs in offspring varies depending on the co-morbid presentation of the NDDs, with the greatest odds associated with outcomes that included ID. Results of paternal-comparison studies suggest that the above associations are likely to be partly confounded by shared familial factors, such as genetic liability.

Clinical characteristics of children with ASD and comorbid ADHD: Association with social impairment and externalizing and internalizing behaviours

BACKGROUND

Autism spectrum disorder (ASD) and attention-deficit hyperactivity disorder (ADHD) are frequently occurring conditions that are often associated (ASD + ADHD). However, there are few comparative studies concerning the clinical presentation in patients formally diagnosed with both ASD and ADHD. Here, we aimed to 1) compare social impairment and externalizing/internalizing behavioural problems across four groups of children: ASD + ADHD, ASD alone, ADHD alone, and typical development and 2) examine their bidirectional relationship with ASD and/or ADHD symptoms.

METHODS

This study included 186 participants from 6 to 12 years of age: single ASD (n = 98), ASD + ADHD (n = 29), single ADHD (n = 28), and TD (n = 31).

RESULTS

The results showed that children in the ASD + ADHD and single ASD groups had a higher level of social impairment than those in the single ADHD group. In addition, children in the single ADHD group presented a greater attention deficit than those in the single ASD group. Externalizing /internalizing behaviours were more frequent in all groups with neuro-developmental disorders than in typical development. In addition, externalizing behavioural problems were related to ADHD severity in the ASD + ADHD and single ADHD groups, whereas internalizing behaviours were related to ASD severity.

CONCLUSIONS

These findings highlight the specific needs of children who have both ASD and ADHD and underscore the necessity of individualizing their interventions.

Dysfunction of the serotonergic system in the brain of synapsin triple knockout mice is associated with behavioral abnormalities resembling synapsin-related human pathologies

Synapsins (Syns) are a family of phosphoproteins associated with synaptic vesicles (SVs). Their main function is to regulate neurotransmitter release by maintaining a reserve pool of SVs at the presynaptic terminal. Previous studies reported that the deletion of one or more Syn genes in mice results in an epileptic phenotype and autism-related behavioral abnormalities. Here we aimed at characterizing the behavioral phenotype and neurobiological correlates of the deletion of Syns in a Syn triple knockout (TKO) mouse model. Wild type (WT) and TKO mice were tested in the open field, novelty suppressed feeding, light-dark box, forced swim, tail suspension and three-chamber sociability tests. Using in vivo electrophysiology, we recorded the spontaneous activity of dorsal raphe nucleus (DRN) serotonin (5-HT) and ventral tegmental area (VTA) dopamine (DA) neurons. Levels of 5-HT and DA in the frontal cortex and hippocampus of WT and TKO mice were also assessed using a High-Performance Liquid Chromatography. TKO mice displayed hyperactivity and impaired social and anxiety-like behavior. Behavioral dysfunctions were accompanied by reduced firing activity of DRN 5-HT, but not VTA DA, neurons. TKO mice also showed increased responsiveness of DRN 5-HT-1A autoreceptors, measured as a reduced dose of the 5-HT-1A agonist 8-OH-DPAT necessary to inhibit DRN 5-HT firing activity by 50%. Finally, hippocampal 5-HT levels were lower in TKO than in WT mice. Overall, Syns deletion in mice leads to a reduction in DRN 5-HT firing activity and hippocampal 5-HT levels along with behavioral alterations reminiscent of human neuropsychiatric conditions associated with Syn dysfunction.

Glial Cells and Their Contribution to the Mechanisms of Action of Cannabidiol in Neuropsychiatric Disorders

Cannabidiol (CBD) is a phytocannabinoid with a broad-range of therapeutic potential in several conditions, including neurological (epilepsy, neurodegenerative diseases, traumatic and ischemic brain injuries) and psychiatric disorders (schizophrenia, addiction, major depressive disorder, and anxiety). The pharmacological mechanisms responsible for these effects are still unclear, and more than 60 potential molecular targets have been described. Regarding neuropsychiatric disorders, most studies investigating these mechanisms have focused on neuronal cells. However, glial cells (astrocytes, oligodendrocytes, microglia) also play a crucial role in keeping the homeostasis of the central nervous system. Changes in glial functions have been associated with neuropathological conditions, including those for which CBD is proposed to be useful. Mostly in vitro studies have indicated that CBD modulate the activation of proinflammatory pathways, energy metabolism, calcium homeostasis, and the proliferative rate of glial cells. Likewise, some of the molecular targets proposed for CBD actions are f expressed in glial cells, including pharmacological receptors such as CB1, CB2, PPAR-γ, and 5-HT1A. In the present review, we discuss the currently available evidence suggesting that part of the CBD effects are mediated by interference with glial cell function. We also propose additional studies that need to be performed to unveil the contribution of glial cells to CBD effects in neuropsychiatric disorders.

Sensory processing related to attention in children with ASD, ADHD, or typical development: results from the ELENA cohort

Autism-spectrum disorder (ASD) and attention-deficit hyperactivity disorder (ADHD) are early neurodevelopmental conditions that share clinical characteristics, raising important issues in clinical diagnosis. We aimed to compare (1) sensory processing in four groups of children: ASD alone, ASD + ADHD, ADHD alone, and typical development (TD) and (2) the association between sensory processing and attention in the three groups with neurodevelopmental disorders. Our sample included 120 children aged from 6 to 12 years divided into four groups: ASD alone (N = 43), ASD + ADHD (N = 18), ADHD alone (N = 28), and TD (N = 31). Atypical sensory processing was more frequent in ASD and/or ADHD than in TD, without a significant difference between ASD and ADHD. However, the variance analysis of attention problems revealed differences between the ADHD and ASD groups. Thus, the rate of atypical sensory processing was comparable between the ASD and ADHD groups, suggesting that further studies are needed to explore atypical SP in all neurodevelopmental disorders.

Adult attention-deficit Hyperactivity disorder: From clinical reality toward conceptual clarity

There is ambiguity about the clinical picture and concept of attention-deficit hyperactivity disorder (ADHD) in adults. Relevant literature was extracted from various search engines, analyzed, and interpreted. Available literature suggests a significant prevalence of ADHD in the adult population affecting the quality of socio-occupational functioning. Inattentiveness was more commonly present than hyperactivity-impulsivity. Frequent comorbidities with other psychiatric disorders like anxiety disorders and substance use disorders were noted. Pharmacological management and psychotherapy have been found effective in its management. ADHD is a disorder across the lifespan and fairly prevalent among adults. Greater awareness and more research are required for a better understanding of Adult ADHD and its effective management.

Medications for attention-deficit/hyperactivity disorder in individuals with or without coexisting autism spectrum disorder: analysis of data from the Swedish prescribed drug register

BACKGROUND

Clinical studies found that medication for attention-deficit/hyperactivity disorder (ADHD) is effective in coexisting autism spectrum disorder (ASD), but current research is based on small clinical studies mainly performed on children or adolescents. We here use register data to examine if individuals with ADHD and coexisting ASD present differences in the prescribing patterns of ADHD medication when compared to individuals with pure ADHD.

METHODS

Data with information on filled prescriptions and diagnoses was retrieved from the Swedish Prescribed Drug Register and the National Patient Register. We identified 34,374 individuals with pure ADHD and 5012 individuals with ADHD and coexisting ASD, aged between 3 and 80 years. The first treatment episode with ADHD medications (≥ 2 filled prescriptions within 90 days) and daily doses of methylphenidate during a 3-year period was measured. Odds ratios (ORs) were calculated for the likelihood of being prescribed ADHD medication in individuals with and without ASD and Wilcoxon rank-sum test was used to compare group differences in dose per day.

RESULTS

Individuals with ADHD and coexisting ASD were less likely to start continuous treatment with ADHD medication (ADHD 80.5%; ADHD with ASD 76.2%; OR, 0.80; 95% confidence interval, 0.75-0.86), were less likely to be prescribed methylphenidate, and were more commonly prescribed second line treatments such as dexamphetamine, amphetamine, or modafinil. No group difference was observed for atomoxetine. In adults with ADHD and coexisting ASD, methylphenidate was prescribed in lower daily doses over three years as compared to individuals with pure ADHD.

CONCLUSIONS

The findings indicate that there are differences in the medical treatment of individuals with or without ASD. If these differences are due to different medication responses in ASD or due to other factors such as clinicians' perceptions of medication effects in patients with ASD, needs to be further studied.

Chronic Physical Activity for Attention Deficit Hyperactivity Disorder and/or Autism Spectrum Disorder in Children: A Meta-Analysis of Randomized Controlled Trials

Purpose: To explore the effects of physical activity (PA) intervention on executive function (EF) and motor skills (MS) among children with attention deficit hyperactivity disorder and/or autism spectrum disorder (ASD).

Methods: Relevant studies were sourced from PubMed, Web of Science, EMBASE, Cochrane Library, CNKI and Wanfang Data. Only randomized controlled trials (RCT) were included based upon the following criteria: (1) participants were children and clinically diagnosed with ADHD/ASD, (2) intervention strategies were identified as chronic physical activity, and (3) EF (e.g., cognitive flexibility) and/or MS (e.g., gross motor skills) were measured at baseline and post-intervention and compared with an eligible control group.

Results: Eleven studies involving 346 participants were finally identified. PA elicited significant improvements in EF and MS in children with ADHD/ASD. Regarding changes in the EF of participants, PA showed a great improvement in overall EF [standardized mean difference (SMD): 0.90, 95% confidence interval (CI) 0.49–1.30, p < 0.00001], inhibitory control (SMD: 1.30, 95% CI 0.58–2.02, p = 0.0004) and cognitive flexibility (SMD: 0.85, 95% CI 0.42–1.29, p = 0.0001), but no significant improvement in working memory (SMD: 0.28, 95% CI −0.15–0.71, p = 0.20). Significant improvements were also found with respect to gross motor skills (SMD: 0.80, 95% CI 0.30–1.30, p = 0.002), but no significant changes were found in fine motor skills (SMD: 0.30, 95% CI −0.91–1.52, p = 0.62).

Conclusion: Chronic PA interventions may promote EF and MS in children with ADHD/ASD, especially in inhibitory control, cognitive flexibility, and gross motor skills. However, PA interventions seemed to have insignificant effects on working memory and fine motor skills to children with ADHD/ASD.

PROSPERO registration number: CRD42019118622

Autistic spectrum disorder symptoms in children and adolescents with attention-deficit/hyperactivity disorder: a meta-analytical review

BACKGROUND

Research identifies highly variable prevalence estimates for autism spectrum disorder (ASD) in children and adolescents with attention deficit hyperactivity disorder (ADHD), particularly between community and clinical samples, warranting quantitative meta-analyses to investigate the true prevalence of ASD in children and adolescents with ADHD.

METHODS

Studies were identified through a systematic literature search of PsycINFO, MEDLINE and Web of Science through January 2018. Twenty-two publications met inclusion criteria (total N = 61 985). Two random effects meta-analyses were conducted: (1) to identify the proportion of children and adolescents with ADHD that met criteria for ASD; and (2) to compare the severity of dimensionally-measured ASD symptomology in children and adolescents with and without ADHD.

RESULTS

The overall pooled effect for children and adolescents with ADHD who met threshold for ASD was 21%. There was no significant difference between community samples (19%) and clinical samples (24%) or between US studies v. those from other countries. Children and adolescents with ADHD had substantially more dimensionally-measured ASD traits compared with those who did not have ADHD (d = 1.23).

CONCLUSION

The findings provide further evidence that ADHD and ASD are associated in nature. Clinical and research implications are discussed.

The Impact of Atypical Sensory Processing on Adaptive Functioning and Maladaptive Behaviors in Autism Spectrum Disorder During Childhood: Results From the ELENA Cohort

Atypical sensory processing is common in autism spectrum disorders (ASD), but their role in adaptive difficulties and problem behaviors is poorly understood. Our aim was to determine the prevalence and type of atypical sensory processing in children with ASD and investigate its impact on their adaptive functioning and maladaptive behaviors. We studied a subsample of 197 children rigorously diagnosed with ASD from the ELENA cohort. Children were divided into atypical and typical sensory processing groups and several independent variables were compared, including adaptive functioning and maladaptive behaviors. Overall, 86.8% of the children had at least one atypical sensory pattern and all sensory modalities were disturbed. Atypical sensory processing explained a significant part of the variance of behavioral problems.

Preliminary Psychometrics for the Executive Function Challenge Task: A Novel, "Hot" Flexibility, and Planning Task for Youth

OBJECTIVE

Executive functions (EF) drive health and educational outcomes and therefore are increasingly common treatment targets. Most treatment trials rely on questionnaires to capture meaningful change because ecologically valid, pediatric performance-based EF tasks are lacking. The Executive Function Challenge Task (EFCT) is a standardized, treatment-sensitive, objective measure which assesses flexibility and planning in the context of provocative social interactions, making it a "hot" EF task.

METHOD

We investigate the structure, reliability, and validity of the EFCT in youth with autism (Autism Spectrum Disorder; n = 129), or attention deficit hyperactivity disorder with flexibility problems (n = 93), and typically developing (TD; n = 52) youth.

RESULTS

The EFCT can be coded reliably, has a two-factor structure (flexibility and planning), and adequate internal consistency and consistency across forms. Unlike a traditional performance-based EF task (verbal fluency), it shows significant correlations with parent-reported EF, indicating ecological validity. EFCT performance distinguishes youth with known EF problems from TD youth and is not significantly related to visual pattern recognition, or social communication/understanding in autistic children.

CONCLUSIONS

The EFCT demonstrates adequate reliability and validity and may provide developmentally appropriate, treatment-sensitive, and ecologically valid assessment of "hot" EF in youth. It can be administered in controlled settings by masked administrators.

Neurobehavioral changes arising from early life dopamine signaling perturbations

Dopamine (DA) signaling is critical to the modulation of multiple brain functions including locomotion, reinforcement, attention and cognition. The literature provides strong evidence that altered DA availability and actions can impact normal neurodevelopment, with both early and enduring consequences on anatomy, physiology and behavior. An appreciation for the developmental contributions of DA signaling to brain development is needed to guide efforts to preclude and remedy neurobehavioral disorders, such as attention-deficit/hyperactivity disorder, addiction, bipolar disorder, schizophrenia and autism spectrum disorder, each of which exhibits links to DA via genetic, cellular and/or pharmacological findings. In this review, we highlight research pursued in preclinical models that use genetic and pharmacological approaches to manipulate DA signaling at sensitive developmental stages, leading to changes at molecular, circuit and/or behavioral levels. We discuss how these alterations can be aligned with traits displayed by neuropsychiatric diseases. Lastly, we review human studies that evaluate contributions of developmental perturbations of DA systems to increased risk for neuropsychiatric disorders.

Cortical signatures in behaviorally clustered autistic traits subgroups: a population-based study

Extensive heterogeneity in autism spectrum disorder (ASD) has hindered the characterization of consistent biomarkers, which has led to widespread negative results. Isolating homogenized subtypes could provide insight into underlying biological mechanisms and an overall better understanding of ASD. A total of 1093 participants from the population-based "Healthy Brain Network" cohort (Child Mind Institute in the New York City area, USA) were selected based on score availability in behaviors relevant to ASD, aged 6-18 and IQ >= 70. All participants underwent an unsupervised clustering analysis on behavioral dimensions to reveal subgroups with ASD traits, identified by the presence of social deficits. Analysis revealed three socially impaired ASD traits subgroups: (1) high in emotionally dysfunctional traits, (2) high in ADHD-like traits, and (3) high in anxiety and depressive symptoms. 527 subjects had good quality structural MRI T1 data. Site effects on cortical features were adjusted using the ComBat method. Neuroimaging analyses compared cortical thickness, gyrification, and surface area, and were controlled for age, gender, and IQ, and corrected for multiple comparisons. Structural neuroimaging analyses contrasting one combined heterogeneous ASD traits group against controls did not yield any significant differences. Unique cortical signatures, however, were observed within each of the three individual ASD traits subgroups versus controls. These observations provide evidence of ASD traits subtypes, and confirm the necessity of applying dimensional approaches to extract meaningful differences, thus reducing heterogeneity and paving the way to better understanding ASD traits.

From Toddlerhood to Adolescence, Trajectories and Predictors of Outcome: Long-Term Follow-Up Study in Autism Spectrum Disorder

This study is one of a very few prospective long-term studies in autism spectrum disorder (ASD). The study compared outcome trajectories in three adolescent groups (T2): "best outcome" (BO, n = 11) did not meet cut-off points for ASD and IQ scores ≥85; high functioning (HF-ASD, n = 14); and lower functioning (LF-ASD, n = 43). Additionally, the study searched for characteristics at toddlerhood (T1) that may predict belonging to the above groups. The study included 68 adolescents (63 males) diagnosed with ASD at toddlerhood (mean age: 13:10 years), mean follow-up time was 11:7 years. Participants underwent comprehensive assessments at T1 and T2. Different trajectories were found for the three defined groups. The BO group improved significantly in cognitive ability, autism severity, and adaptive skills in comparison to no improvement for the LF-ASD group or partial progress for the HF-ASD group. At toddlerhood, better cognition and less severe autism social affect symptoms were generally associated with a better outcome. Early social behaviors including better "pointing," "facial expression directed to others," "showing," and "response to joint attention" were associated with membership in the BO group. In addition, the BO group had the lowest prevalence of significant T2 inattention and anxiety symptoms. No significant differences between the three outcome groups were noted in the birth and prevalence of medical problems. Higher cognitive ability and better T1 showing and pointing behaviors predicted better outcome. The study points to the change in autism severity over time and to the prognostic value of early developmental abilities, social engagement behaviors, and the existence of comorbidities. Autism Res 2020, 13: 1130-1143. © 2020 International Society for Autism Research and Wiley Periodicals LLC. LAY SUMMARY: This long-term study compared characteristics of toddlers diagnosed with autism spectrum disorder (ASD) in three outcome groups in adolescence: best outcome (BO-average IQ/not meeting criteria for ASD), high-functioning ASD, and low-functioning ASD (LF-ASD). At toddlerhood, the BO group displayed less severe autism symptoms, mostly in sharing interests, compared to the LF-ASD group. The BO group had fewer inattention and anxiety symptoms than the two ASD groups. Additionally, early cognitive level and social engagement behaviors predicted outcome in ASD.

Propionic acid induced behavioural effects of relevance to autism spectrum disorder evaluated in the hole board test with rats

Autism spectrum disorders (ASD) are a set of neurodevelopmental disorders characterized by abnormal social interactions, impaired language, and stereotypic and repetitive behaviours. Among genetically susceptible subpopulations, gut and dietary influences may play a role in etiology. Propionic acid (PPA), produced by enteric gut bacteria, crosses both the gut-blood and the blood-brain barrier. Previous research has demonstrated that repeated intracerebroventricular (ICV) infusions of PPA in adult rats produce behavioural and neuropathological changes similar to those seen in ASD patients, including hyperactivity, stereotypy, and repetitive movements. The current study examined dose and time related changes of exploratory and repetitive behaviours with the use of the hole-board task. Adult male Long-Evans rats received ICV infusions twice a day, 4 h apart, of either buffered PPA (low dose 0.052 M or high dose 0.26 M, pH 7.5, 4 μL/infusion) or phosphate buffered saline (PBS, 0.1 M) for 7 consecutive days. Locomotor activity and hole-poke behaviour were recorded daily in an automated open field apparatus (Versamax), equipped with 16 open wells, for 30 min immediately after the second infusion. In a dose dependent manner PPA infused rats displayed significantly more locomotor activity, stereotypic behaviour and nose-pokes than PBS infused rats. Low-dose PPA animals showed locomotor activity levels similar to those of PBS animals at the start of the infusion schedule, but gradually increased to levels comparable to those of high-dose PPA animals by the end of the infusion schedule, demonstrating a dose and time dependent effect of the PPA treatments.

Data-driven identification of subtypes of executive function across typical development, attention deficit hyperactivity disorder, and autism spectrum disorders

BACKGROUND

Impairment of executive function (EF), the goal-directed regulation of thoughts, actions, and emotions, drives negative outcomes and is common across neurodevelopmental disorders including attention deficit hyperactivity disorder (ADHD) and autism spectrum disorder (ASD). A primary challenge to its amelioration is heterogeneity in symptom expression within and across disorders. Parsing this heterogeneity is necessary to attain diagnostic precision, a goal of the NIMH Research Domain Criteria Initiative. We aimed to identify transdiagnostic subtypes of EF that span the normal to impaired spectrum and establish their predictive and neurobiological validity.

METHODS

Community detection was applied to clinical parent-report measures in 8-14-year-old children with and without ADHD and ASD from two independent cohorts (discovery N = 320; replication N = 692) to identify subgroups with distinct behavioral profiles. Support vector machine (SVM) classification was used to predict subgroup membership of unseen cases. Preliminary neurobiological validation was obtained with existing functional magnetic resonance imaging (fMRI) data on a subsample (N = 84) by testing hypotheses about sensitivity of EF subgroups versus DSM categories.

RESULTS

We observed three transdiagnostic EF subtypes characterized by behavioral profiles that were defined by relative weakness in: (a) flexibility and emotion regulation; (b) inhibition; and (c) working memory, organization, and planning. The same tripartite structure was also present in the typically developing children. SVM trained on the discovery sample and tested on the replication sample classified subgroup membership with 77.0% accuracy. Split-half SVM classification on the combined sample (N = 1,012) yielded 88.9% accuracy (this SVM is available for public use). As hypothesized, frontal-parietal engagement was better distinguished by EF subtype than DSM diagnosis and the subgroup characterized with inflexibility failed to modulate right IPL activation in response to increased executive demands.

CONCLUSIONS

The observed transdiagnostic subtypes refine current diagnostic nosology and augment clinical decision-making for personalizing treatment of executive dysfunction in children.