A review on cognitive and brain endophenotypes that may be common in autism spectrum disorder and attention-deficit/hyperactivity disorder and facilitate the search for pleiotropic genes

Transdiagnostic relationships between childhood adversity and cortical thickness of the rostral anterior cingulate cortex

Childhood adversity (CA) is the leading preventable risk factor for mental illness. While CA can exacerbate affective symptoms across various psychiatric disorders, its impact on brain morphology, particularly the rostral anterior cingulate cortex (rACC), has mainly been studied in specific stress-related psychiatric disorders, such as depression and anxiety disorders. Therefore, we set out to disentangle the relationships between CA, psychopathology and brain structure across a broader range of psychiatric disorders. We studied 227 patients with stress-related and/or neurodevelopmental disorders and 95 healthy controls. We focused on the rACC, as this region is highly impacted by CA and has a pivotal role in affective functions across psychiatric disorders. The presence of CA was associated with decreased left rACC thickness across the whole sample, independent of psychopathology. Additionally, the contralateral right rACC was associated with psychopathology, with psychiatric patients having a thinner rACC compared to healthy controls, which was most pronounced in the stress-related disorders group. While left rACC thickness negatively correlated with social anxiety-related concerns, right rACC thickness negatively correlated with various core symptoms of stress-related and neurodevelopmental disorders. Finally, our exploratory analyses across cortical regions did not reveal any robust effects that survived multiple comparison correction. Taken together, our results suggest that within the stress-related disorders group, the CA-related thinning of the left rACC may compound the effects of the affected right rACC. This 'double hit' in stress-related disorders may contribute to the well-established phenomenon that CA leads to a worse illness trajectory in these disorders.

Comparison of ADOS-2 scores in adults with attention deficit hyperactivity disorder and autism spectrum disorder

Aim

Attention deficit hyperactivity disorder (ADHD) symptoms persist significantly into adulthood; however, only a few studies have examined the overlap between ADHD and autism spectrum disorder (ASD) symptoms in adults. This study compared ASD symptoms in adults with ASD, ADHD, and neurotypical controls using the Autism Diagnostic Observation Schedule, Second Edition (ADOS-2).

Methods

In total, 150 adults (69 with ADHD [mean age, 34.5 years; 43 men], 50 with ASD [mean age, 33.8 years; 35 men], and 31 controls [mean age, 38.7 years; 17 men]) completed Module 4 of the ADOS-2, the Autism Spectrum Quotient, Conners' Adult ADHD Rating Scale, and the Wechsler Adult Intelligence Scale.

Results

Consistent with juvenile studies, adults with ADHD exhibited significant ASD symptoms, which were between those with ASD and neurotypical individuals. Item-level analysis suggested more similarities than differences between the two disorders; the differences may be of degree rather than quality.

Conclusion

This study shows the importance of assessing full ASD symptoms in adults with ADHD.

Electrophysiological Abnormalities Associated With Sustained Attention in Children With Attention Deficit Hyperactivity Disorder and Autism Spectrum Disorder

This study investigates electrophysio- logical abnormalities in children with Attention-Deficit/ Hyperactivity Disorder (ADHD) and Autism Spectrum Disorder (ASD) during sustained attention tasks, focusing on vigilance and inhibitory control, and explores associations between neural markers and attentional performance.Children with ADHD (n = 30), ASD (n = 23), and typically developing (TD) children (n = 31) completed a Test of Variables of Attention (TOVA) task while electroencephalography (EEG) was recorded. Event-related potentials (ERPs: P1, N2, P3) and event-related desynchronization/synchronization (ERD/ERS: theta ERS, alpha ERD, beta ERS) were measured and compared across groups. Correlations between electrophysiological features and behavioral performance were analyzedBoth ADHD and ASD groups demonstrated attenuated P1 amplitudes during vigilance task and reduced prefrontal theta ERS during inhibitory control. The ASD group exhibited additional impairments, including attenuated N2 amplitudes in inhibitory control, reduced P3 amplitudes, and weaker alpha ERD across conditions. The ADHD group showed additional deficits in theta ERS. Notably, N2 amplitude and theta ERS during vigilance state significantly correlated with response time measures. Children with ADHD and ASD share deficits in primary visual stimulus processing and inhibitory attention allocation. ASD-specific impairments involve top-down processing and inhibition, while ADHD-specific challenges involve attentional allocation and modulation. These findings enhance the electrophysiological understanding of sustained attention in ADHD and ASD, offering insights that may inform future diagnostic and intervention strategies.

Methods for Assessing Neurodevelopmental Disorders in Mice: A Critical Review of Behavioral Tests and Methodological Considerations Searching to Improve Reliability

Many neurobehavioral tests are used for the assessment of human-like behaviors in animals. Most of them were developed in rodents and are used for the assessment of animal models that mimic human neurodevelopmental and neuropsychiatric disorders (NDDs). We have described tests for assessing social behavior, social interaction, and social communication; tests for restricted and repetitive behaviors; tests for cognitive impairment, for sensory stimuli, for anxiety like behavior, and for motor coordination deviations. These tests are used to demonstrate autistic-like behavior as well as other NDDs. We described possible general pitfalls in the performance of such studies, as well as probable individual errors for each group of tests assessing specific behavior. The mentioned pitfalls may induce crucial errors in the interpretation of the results, minimizing the reliability of specific models of defined human NDD. It is imperative to minimize these pitfalls and use sufficient and reliable tests that can demonstrate as many of the traits of the human disorder, grade the severity of the specific deviations and the severity of the tested NDD by using a scoring system. Due to possible gender differences in the clinical presentations of NDD, it is important to carry out studies on males and females.

Understanding Sensory-Motor Disorders in Autism Spectrum Disorders by Extending Hebbian Theory: Formation of a Rigid-Autonomous Phase Sequence

Autism spectrum disorder is a neuropsychiatric disorder characterized by persistent deficits in social communication and social interaction and restricted, repetitive patterns of behavior, interests, or activities. The symptoms invariably appear in early childhood and cause significant impairment in social, occupational, and other important functions. Various abnormalities in the genetic, neurological, and endocrine systems of patients with autism spectrum disorder have been reported as the etiology; however, no clear factor leading to the onset of the disease has been identified. Additionally, higher order cognitive dysfunctions, which are represented by a lack of theory of mind, sensorimotor disorders, and memory-related disorders (e.g., flashbacks), have been reported in recent years, but no theoretical framework has been proposed to explain these behavioral abnormalities. In this study, we extended Hebb's biopsychology theory to provide a theoretical framework that comprehensively explains the various behavioral abnormalities observed in autism spectrum disorder. Specifically, we propose that a wide range of symptoms in autism spectrum disorder may be caused by the formation of a rigid-autonomous phase sequence (RAPS) in the brain. Using the RAPS formation theory, we propose a biopsychological mechanism that could be a target for the treatment of autism spectrum disorders.

Simple Executive Function as an endophenotype of autism-ADHD, and differing associations between simple versus complex Executive Functions and autism/ADHD traits

Autism and ADHD are associated with difficulties with Executive Functions (EFs), but the prevalence and nature of these difficulties in early development is not well understood. In this longitudinal study, 107 children with a family history of autism and/or ADHD (FH-autism/ADHD), and 24 children with No-FH-autism/ADHD completed multiple EF tasks (5 at age 2 years, 7 at age 3 years). Parents reported on their child's autism- (Q-CHAT at age 2, SRS-2 at age 3), and ADHD-related traits (CBCL DSM-ADHD scale, both ages). Compared to the No-FH-autism/ADHD group, the FH-autism/ADHD group showed lower scores on simple EFs (involving response inhibition, and holding in mind) at ages 2 and 3. Exploratory analysis linked FH-autism specifically with lower Executive Attention (top-down attentional control) at age 2, and the combination of FH-autism and FH-ADHD with lower Complex EF (involving selectively deploying responses, or updating information) at age 3. Three-year-olds' Simple EF scores were negatively associated with ADHD-related traits. Complex EF scores were negatively associated with autism traits (before correcting for multiple comparisons). Toddlers with a family history of autism and/or ADHD may benefit from interventions to support simple EF development, whilst those already showing autistic traits may benefit from support with more-complex EF skills.

Longitudinal Predictors of Adaptive Functioning in Emerging Adults with and without Autism Spectrum Disorder

Individuals with autism spectrum disorder (ASD) display heterogeneity in adaptive functioning, underscoring the need to identify predictors to inform clinical and scientific interventions. We investigated the longitudinal associations between an autism diagnosis, co-occurring psychopathology symptoms, executive functions (EF) and subsequent adaptive functioning in individuals with and without ASD (IQ > 70). Sixty-six individuals (26 with ASD, 40 without ASD) were assessed at baseline (mean age = 11.8 years, SD = 2.1) and at 10-year follow-up (mean age 21.4, SD = 2.3). The diagnostic evaluation comprised a comprehensive assessment of autism symptoms and emotional and cognitive functioning. Co-occurring psychopathology symptoms were assessed with two measures: self-reported depressive symptoms with the Short Mood and Feelings Questionnaire and parent-reported total problems with the Child Behavior Checklist 6-18. Participants completed neuropsychological tests to evaluate EF. We investigated adaptive functioning by using the Weiss Functional Impairment Rating Scale (WFIRS) which is a self-report measure of impairment in the following domains: family, work, school, life skills, self-concept, social and risk-taking. Among the emerging adults previously diagnosed with ASD, 46% reported living independently, 75% had at least one friend, and 71% were employed or in education. Individuals with ASD reported significantly lower adaptive functioning compared to individuals without ASD (WFIRS Total, Hedges' g = 0.92). Greater EF difficulties in childhood/adolescence predicted lower adaptive functioning in emerging adulthood, surpassing the influence of autism diagnosis and co-occurring symptoms. The findings highlight the influential role of EF, implying that interventions targeting EF difficulties could improve long-term outcomes for individuals with ASD.

Learning from the community: iterative co-production of a programme to support the development of attention, regulation and thinking skills in toddlers at elevated likelihood of autism or ADHD

Programmes designed to support children with known, or increased likelihood of, autism or ADHD often focus on reducing behaviours central to a clinical diagnosis. However, supporting children to pursue their own goals and cope with everyday life through fostering executive function (EF) development, without enforcing neuro-normative assumptions, may be more acceptable to neurodivergent people, and more beneficial. The co-production process for this neurodiversity-affirming programme involved: Review of research priorities identified during published public-and-clinician consultations; iterative programme development through two pilot rounds with a general community sample; and consultation with stakeholders (parents with a connection to autism or ADHD, alongside early years specialists, psychologists and therapists) to check acceptability of the proposal, and refine the logic model and materials. The logic model for the resultant programme-Supporting Toddlers with a connection to autism or ADHD to develop strong Attention, Regulation and Thinking skills (START)-involves three mechanisms of change: The child has appropriate play-based opportunities to practise EF skills; Parenting behaviours linked to strong EFs are encouraged; Parents are empowered to improve environmental-fit for their child so that EF stressors are reduced.

Familial co-aggregation and shared familiality among neurodevelopmental problems and with aggressive behavior, depression, anxiety, and substance use

OBJECTIVE

To refine the knowledge on familial transmission, we examined the (shared) familial components among neurodevelopmental problems (i.e. two attention-deficit/hyperactivity-impulsivity disorder [ADHD] and six autism spectrum disorder [ASD] subdomains) and with aggressive behavior, depression, anxiety, and substance use.

METHODS

Data were obtained from a cross-sectional study encompassing 37 688 participants across three generations from the general population. ADHD subdomains, ASD subdomains, aggressive behavior, depression, anxiety, and substance use were assessed. To evaluate familial (co-)aggregation, recurrence risk ratios (λR) were estimated using Cox proportional hazards models. The (shared) familiality (f2), which is closely related to (shared) heritability, was assessed using residual maximum likelihood-based variance decomposition methods. All analyses were adjusted for sex, age, and age2.

RESULTS

The familial aggregation and familiality of neurodevelopmental problems were moderate (λR = 2.40-4.04; f2 = 0.22-0.39). The familial co-aggregation and shared familiality among neurodevelopmental problems (λR = 1.39-2.56; rF = 0.52-0.94), and with aggressive behavior (λR = 1.79-2.56; rF = 0.60-0.78), depression (λR = 1.45-2.29; rF = 0.43-0.76), and anxiety (λR = 1.44-2.31; rF = 0.62-0.84) were substantial. The familial co-aggregation and shared familiality between all neurodevelopmental problems and all types of substance use were weak (λR = 0.53-1.57; rF = -0.06-0.35).

CONCLUSIONS

Neurodevelopmental problems belonging to the same disorder were more akin than cross-disorder problems. That said, there is a clear (shared) familial component to neurodevelopmental problems, in part shared with other psychiatric problems (except for substance use). This suggests that neurodevelopmental disorders, disruptive behavior disorders, and internalizing disorders share genetic and environmental risk factors.

The Effect of Rhythmic Optical Stimulation on Temporal Parameters of Human Sensorimotor Response and Their Relation to the Spectral Characteristics of the Initial EEG

The effect of optical stimulation at a frequency of 10 Hz (OS10Hz) on temporal parameters of sensorimotor activity in healthy subjects (n=32) was studied. The expression of the activation response was determined by the ratio of spectral power values (SPα2, μV2) of the high frequency (10-13 Hz) subrange of the α-rhythm of the initial EEG with closed and opened eyes and the frequency of the maximum α-peak (IAPF). A test for simple motor reaction time was performed under normal and OS10Hz conditions. According to the change in the variability of simple motor reaction time (SDSMRT) under OS10Hz compared to the normal conditions, the subjects were classified into two groups: those who showed a decrease (group 1) and those who showed an increase (group 2) in SDSMRT. The subjects of group 1 had significantly higher IAPF (in the O1 lead with eyes closed) and activation reaction intensity (in the O2, O1, P4, P3, and F3 leads) compared to the subjects of group 2. The obtained data suggest that OS10Hz changes the parameters of psychomotor reactions of an individual, and the direction of changes is mediated by individual features of the initial EEG.

Diagnostic usefulness of 24-h polysomnography for idiopathic hypersomnia co-occurring with neurodevelopmental disorders: A case report

Background

Although central disorders of hypersomnolence (CDH) and attention-deficit/hyperactivity disorder (ADHD) are frequently comorbid, they often remain underdiagnosed, leading to insufficient treatment and sociopsychological outcomes.

Case Presentation

Here, we present a case of a male in his late 20s with ADHD and autism spectrum disorder who exhibited symptoms suggestive of idiopathic hypersomnia (IH), a subtype of CDH. The patient experienced difficulty waking up and dropped out of university. Additionally, although methylphenidate extended-release was prescribed, he often forgot to take his medication, resulting in difficulty waking up until late afternoon. No symptoms related to rapid eye movements sleep were observed. Considering the possibility of concurrent hypersomnia with neurodevelopmental disorders, we conducted 24-h polysomnography (PSG). The results demonstrated total sleep time of 774.5 min (≥660 min). Together with other criteria, we diagnosed him as having IH. Following discharge and discussion with the patient, we provided sleep hygiene education for him, and he resumed day care attendance to establish a social routine.

Conclusion

In cases where hypersomnia may co-occur with neurodevelopmental disorders, active utilization of 24-h PSG enables detailed evaluation of sleep-wake patterns and behaviors, facilitating effective guidance on sleep hygiene and promoting improvements in social rhythms and sociability.

Multiclass classification of Autism Spectrum Disorder, attention deficit hyperactivity disorder, and typically developed individuals using fMRI functional connectivity analysis

Neurodevelopmental conditions, such as Autism Spectrum Disorder (ASD) and Attention Deficit Hyperactivity Disorder (ADHD), present unique challenges due to overlapping symptoms, making an accurate diagnosis and targeted intervention difficult. Our study employs advanced machine learning techniques to analyze functional magnetic resonance imaging (fMRI) data from individuals with ASD, ADHD, and typically developed (TD) controls, totaling 120 subjects in the study. Leveraging multiclass classification (ML) algorithms, we achieve superior accuracy in distinguishing between ASD, ADHD, and TD groups, surpassing existing benchmarks with an area under the ROC curve near 98%. Our analysis reveals distinct neural signatures associated with ASD and ADHD: individuals with ADHD exhibit altered connectivity patterns of regions involved in attention and impulse control, whereas those with ASD show disruptions in brain regions critical for social and cognitive functions. The observed connectivity patterns, on which the ML classification rests, agree with established diagnostic approaches based on clinical symptoms. Furthermore, complex network analyses highlight differences in brain network integration and segregation among the three groups. Our findings pave the way for refined, ML-enhanced diagnostics in accordance with established practices, offering a promising avenue for developing trustworthy clinical decision-support systems.

Gray matter asymmetry alterations in children and adolescents with comorbid autism spectrum disorder and attention-deficit/hyperactivity disorder

Despite the high coexistence of autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD) (ASD + ADHD), the underlying neurobiological basis of this disorder remains unclear. Altered brain structural asymmetries have been verified in ASD and ADHD, respectively, making brain asymmetry a candidate for characterizing this coexisting disorder. Here, we measured the gray matter (GM) volume asymmetry in ASD + ADHD versus ASD without ADHD (ASD-only), ADHD without ASD (ADHD-only), and typically developing controls (TDc). High-resolution T1-weighted data from 48 ASD + ADHD, 63 ASD-only, 32 ADHD-only, and 211 matched TDc were included in our study. We also assessed brain-behavior relationships and the effects of age on GM asymmetry. We found that there were both shared and disorder-specific GM volume asymmetry alterations in ASD + ADHD, ASD-only, and ADHD-only compared with TDc. This finding demonstrates that ASD + ADHD is neither an endophenocopy nor an additive pathology of ASD and ADHD, but an entirely different neuroanatomical pathology. In addition, ASD + ADHD displayed altered GM volume asymmetries in the prefrontal regions responsible for executive function and theory of mind compared with ASD-only. We also found significant effects of age on GM asymmetry. The present study may provide structural insights into the neural basis of ASD + ADHD.

Symptoms of ADHD and Autism Spectrum Disorder Interactively Predict Children's Verbal Fluency

OBJECTIVE

Verbal fluency, the capacity to generate words from a designated category, predicts myriad cognitive and life outcomes. The study investigated verbal fluency in children with ADHD, autism spectrum disorder (ASD), and comorbid ADHD and ASD, to understand how ADHD- and ASD-related symptoms individually and jointly predict verbal fluency, and the underlying linguistic and cognitive substrates.

METHOD

Thirty-three school-aged children with ADHD, 27 with ASD, 25 with comorbid ADHD and ASD, and 39 with typical development, were assessed for ADHD and ASD symptoms and completed a semantic verbal fluency task.

RESULTS

Findings indicated that ADHD and ASD symptoms, especially ADHD hyperactivity-impulsivity symptoms and language-related ASD symptoms, interactively predicted verbal fluency across diagnostic groups.

CONCLUSION

The study implicated the potential cognitive and linguistic mechanisms underlying verbal fluency differences in ADHD and/or ASD, and clinical practices on enhancing verbal fluency in these clinical groups.

Comparing Executive Functions in Children and Adolescents with Autism and ADHD-A Systematic Review and Meta-Analysis

Two neurodevelopmental conditions, autism spectrum disorder (ASD) and attention deficit hyperactivity disorder (ADHD), have been associated with executive function (EF) impairments but the specificity of their impairments is still controversial. The present meta-analysis aimed to identify the differences in EF profiles of ASD, ADHD, and ASD+ADHD in relation to a control group of individuals with typical development (TD) and to understand whether the EF performance could change depending upon the type of measure used to assess EF (performance tests vs. questionnaires). Results from 36 eligible studies revealed that ADHD and ASD showed more difficulties than the TD group in tests and, particularly, in questionnaires. No significant differences in the EF profile emerged between ASD and ADHD when assessed through neuropsychological tests (d = 0.02), while significant differences emerged when assessed through questionnaires, with ADHD having higher ratings than ASD (d = -0.34). EF questionnaires and neuropsychological tests may catch two different constructs of EF, with the former being more predictive of everyday life EF impairments. The comparison between the double diagnosis group (ADHD+ASD) and the clinical groups pointed out that the former has a more similar EF profile to the ADHD-alone one and that it shows more difficulties than ASD-alone.

ASD and ADHD: Divergent activating patterns of prefrontal cortex in executive function tasks?

The functional Near-infrared Spectroscopy (fNIRS) has been more and more widely used to measure the activation state of prefrontal cortex when performing function-related tasks among children with various developmental disorders. Children with autism spectrum disorder (ASD) and attention deficit hyperactivity disorder (ADHD) have shown obvious executive function defects. We aimed to summarize the studies with fNIRS, to summarize the activation patterns of prefrontal cortex (PFC) of participants with ASD or ADHD in performing functional tasks. We selected 630 articles according to PRISMA guidelines, and the eligibility criteria were: 6-16 years old individuals diagnosed with ASD or ADHD by DSM-4 or 5, using fNIRS, having executive function (EF) task, typical development (TD) control, and between-group comparison of PFC activation. Eleven studies were finally included in the quantitative analysis, and compared to TD, ASD and ADHD showed the opposite PFC activation patterns during n-back tasks. We discussed the task-specific PFC activation in young participants with ASD and ADHD, and provided some new ideas on that issue.

The High Rates of Comorbidity among Neurodevelopmental Disorders: Reconsidering the Clinical Utility of Distinct Diagnostic Categories

The boundaries between neurodevelopmental disorders are often indistinct, even among specialists. But do these boundaries exist, or do experts struggle to distinguish and categorize symptoms in order to arrive at a dominant diagnosis while comorbidity continually leaves questions about where each disorder ends and begins? What should be reconsidered? The introduction of the term 'spectrum of neurodevelopmental disorders' could pave the way for a re-appraisal of the clinical continuum of neurodevelopmental disorders. This study aims to highlight the problems that emerge in the field of the differential diagnosis of neurodevelopmental disorders and propose a renegotiation of the distinctiveness criteria.

Altered Intrinsic Brain Spontaneous Activities in Children With Autism Spectrum Disorder Comorbid ADHD

OBJECTIVE

The study involved 17 children with Autism Spectrum Disorder (ASD), 21 with ADHD, 30 with both (ASD + ADHD), and 28 typically developing children (TD).

METHODS

The amplitude of low-frequency fluctuations (ALFF) was measured as a regional brain function index. Intrinsic functional connectivity (iFC) was also analyzed using the region of interest (ROI) identified in ALFF analysis. Statistical analysis was done via one-way ANCOVA, Gaussian random field (GRF) theory, and post-hoc pair-wise comparisons.

RESULTS

The ASD + ADHD group showed increased ALFF in the left middle frontal gyrus (MFG.L) compared to the TD group. In terms of global brain function, the ASD group displayed underconnectivity in specific regions compared to the ASD + ADHD and TD groups.

CONCLUSION

The findings contribute to understanding the neural mechanisms underlying ASD + ADHD.

Cortical responses to social stimuli in infants at elevated likelihood of ASD and/or ADHD: A prospective cross-condition fNIRS study

Autism spectrum disorders (ASD) and attention-deficit hyperactivity disorder (ADHD) are highly prevalent neurodevelopmental conditions that often co-occur and present both common and distinct neurodevelopmental profiles. Studying the developmental pathways leading to the emergence of ASD and/or ADHD symptomatology is crucial in understanding neurodiversity and discovering the mechanisms that underpin it. This study used functional near-infrared spectroscopy (fNIRS) to investigate differences in cortical specialization to social stimuli between 4- to 6-month-old infants at typical and elevated likelihood of ASD and/or ADHD. Results showed that infants at both elevated likelihood of ASD and ADHD had reduced selectivity to vocal sounds in left middle and superior temporal gyrus. Furthermore, infants at elevated likelihood of ASD showed attenuated responses to visual social stimuli in several cortical regions compared to infants at typical likelihood. Individual brain responses to visual social stimuli were associated with later autism traits, but not ADHD traits. These outcomes support our previous observations showing atypical social brain responses in infants at elevated likelihood of ASD and align with later atypical brain responses to social stimuli observed in children and adults with ASD. These findings highlight the importance of characterizing antecedent biomarkers of atypicalities in processing socially relevant information that might contribute to both phenotypic overlap and divergence across ASD and ADHD conditions and their association with the later emergence of behavioural symptoms.

The effectiveness of weighted blankets on sleep and everyday activities - A retrospective follow-up study of children and adults with attention deficit hyperactivity disorder and/or autism spectrum disorder

BACKGROUND

Attention deficit hyperactivity disorder (ADHD) and Autism Spectrum Disorder (ASD) are often accompanied by sleep problems influencing social, emotional and cognitive functioning in everyday activities.

AIM

The aim of this study was to investigate whether the use of a weighted blanket has a positive impact on sleep and everyday activities in individuals with ADHD and/or ASD.

MATERIAL AND METHODS

The study included 85 individuals diagnosed with ADHD and/or ASD, 48 children aged ≤17 (57%) and 37 adults ≥18 years (44%), who were prescribed with a weighted blanket. The participants responded via a telephone interview.

RESULTS

Findings demonstrated that a weighted blanket improved abilities related to falling asleep, sleeping the whole night, and relaxing during the day. Using a weighted blanket improved morning/evening daily routine, including preparing/going to sleep and waking up in the morning.

CONCLUSIONS

Weighted blankets showed positive impact on falling asleep, sleeping the whole night, and relaxing during the day, and they were used frequently by children and adults with ADHD and/or ASD. Findings indicate that a weighted blanket improved morning/evening routine, however this research area needs further investigation using both subjective and objective parameters.

The Prevalence of Attention Deficit/Hyperactivity Disorder Symptoms in Children and Adolescents With Autism Spectrum Disorder Without Intellectual Disability: A Systematic Review

OBJECTIVE

ADHD commonly co-occurs with ASD without ID in young people. It has been difficult to obtain accurate prevalence estimates of ADHD in this population, as a dual-diagnosis was not permitted until DSM-V. We systematically reviewed the literature on the prevalence of ADHD symptoms in young people with ASD without ID.

METHOD

9,050 articles were identified through six databases. Articles were reviewed against inclusion and exclusion criteria and 23 studies were included.

RESULTS

ADHD symptom prevalence varied from 2.6% to 95.5%. We discuss these findings according to the ADHD assessment measure, informant, diagnostic criteria, risk of bias rating and recruitment pool.

CONCLUSION

ADHD symptoms are common in young people with ASD without ID, but there is substantial variance in study reporting. Future studies should recruit participants from community sources, provide information on key sociodemographic sample characteristics and assess ADHD with standardized diagnostic criteria, using both parent/carer and teacher report.

Effects of Intersectionality Along the Pathway to Diagnosis for Autistic Children With and Without Co-occurring Attention Deficit Hyperactivity Disorder in a Nationally-Representative Sample

Children with complex behavioral profiles (e.g., ASD + ADHD) may experience delays in obtaining a final diagnosis. Low-resource or underrepresented groups may be at even greater risk for delayed diagnosis. We assessed the effect of sociodemographic factors, symptom complexity and co-occurring conditions, and identifier of first symptoms on diagnostic trajectories among children aged 3-17 years diagnosed with ASD (n = 52) or ASD + ADHD (n = 352) from a nationally-representative sample. Race/ethnicity and gender disparities were evident in both groups. Race, symptom complexity, and co-occuring conditions predicted age of final diagnosis and wait time between first concern and final diagnosis, both of which were staggeringly high. Results suggest a complex influence of sociodemographic factors on the diagnostic pathway, and risk of health disparities as a function of intersectionality.

Prepotent response inhibition in autism: Not an inhibitory deficit?

Research outcomes on prepotent response inhibition in neurodevelopmental conditions during adulthood seem inconsistent, especially in autism. To gain further insight in these inconsistencies, the current study investigates inhibitory performance, as well as task strategies such as adaptive behavior during inhibitory tasks in autistic adults. As Attention-Deficit/Hyperactivity Disorder (ADHD) is often co-occurring in autism and associated with differences in both inhibition and adaptation, the role of ADHD symptoms is explored. Additionally, prior research is extended to middle- and late-adulthood, and the role of cognitive aging is assessed. Hundred-and-five autistic adults and 139 non-autistic adults (age: 20-80 yrs) were compared on a Go-NoGo task. No significant group differences in inhibitory difficulties (commission errors) or adaptation (post error slowing) were observed, and both did not relate significantly to ADHD symptoms. However, when controlling for reaction time autistic individuals made significantly more inhibitory errors than non-autistic individuals, yet the effect size was modest (Cohen's d = .27). Exploratory analyses showed that adaption significantly related to inhibition in non-autistic individuals only, possibly hinting at altered adaptive behavior during inhibitory tasks in autistic adults. ADHD symptoms related to response variability in the autism group only. Furthermore, task strategy changed with older age in both groups, with slower and more cautious responses at older age. Taken together, although minor differences may exist, autistic and non-autistic people show largely similar patterns of inhibitory behavior throughout adulthood. Differences in task timing and strategy seem relevant for future longitudinal studies on cognitive aging across neurodevelopmental conditions.

Relationship between autonomic arousal and attention orienting in children and adolescents with ADHD, autism and co-occurring ADHD and autism

INTRODUCTION

Attention-Deficit/Hyperactivity Disorder (ADHD) and Autism Spectrum Disorder (ASD) may be characterized by different profiles of visual attention orienting. However, there are also many inconsistent findings emerging from the literature, probably due to the fact that the potential effect of autonomic arousal (which has been proposed to be dysregulated in these conditions) on oculomotor performance has not been investigated before. Moreover, it is not known how visual attention orienting is affected by the co-occurrence of ADHD and autism in people with a double diagnosis.

METHODS

99 children/adolescents with or without ADHD and/or autism (age 10.79 ± 2.05 years, 65% boys) completed an adapted version of the gap-overlap task (with baseline and overlap trials only). The social salience and modality of stimuli were manipulated between trials. Eye movements and pupil size were recorded. We compared saccadic reaction times (SRTs) between diagnostic groups and investigated if a trial-by-trial association existed between pre-saccadic pupil size and SRTs.

RESULTS

Faster orienting (shorter SRT) was found for baseline compared to overlap trials, faces compared to non-face stimuli and-more evidently in children without ADHD and/or autism-for multi-modal compared to uni-modal stimuli. We also found a linear negative association between pre-saccadic pupil size and SRTs, in autistic participants (without ADHD), and a quadratic association in children with ADHD (without autism), for which SRTs were slower when intra-individual pre-saccadic pupil size was smallest or largest.

CONCLUSION

Our findings are in line with previous literature and indicate a possible effect of dysregulated autonomic arousal on oculomotor mechanisms in autism and ADHD, which should be further investigated in future research studies with larger samples, to reliably investigate possible differences between children with single and dual diagnoses.

Peripheral Inflammatory Markers in Autism Spectrum Disorder and Attention Deficit/Hyperactivity Disorder at Adolescent Age

Autism spectrum disorder (ASD) and attention deficit/hyperactivity disorder (ADHD) are associated with immune dysregulation. We aimed to estimate the pro- and anti-inflammatory activity/balance in ASD and ADHD patients at a little-studied adolescent age with respect to sex. We evaluated 20 ASD patients (5 girls, average age: 12.4 ± 1.9 y), 20 ADHD patients (5 girls, average age: 13.4 ± 1.8 y), and 20 age- and gender-matched controls (average age: 13.2 ± 1.9 y). The evaluated parameters included (1) white blood cells (WBCs), neutrophils, monocytes, lymphocytes, platelets, platelet distribution width (PDW), mean platelet volume, and derived ratios, as well as (2) cytokines-interferon-gamma, interleukin (IL)-1α, IL-1β, IL-2, IL-4, IL-6, IL-8, and IL-10, tumor necrosis factor-alpha (TNF-α), and derived profiles and ratios. ASD adolescents showed higher levels of WBC, monocytes, IL-1α, IL-1β, IL-2, IL-4, IL-6, IL-8, and IL-10, macrophages (M)1 profile, and anti-inflammatory profile than the controls, with ASD males showing higher monocytes, IL-6 and IL-10, anti-inflammatory profile, and a lower T-helper (Th)1/Th2+T-regulatory cell ratio than control males. The ADHD adolescents showed higher levels of PDW, IL-1β and IL-6, TNF-α, M1 profile, proinflammatory profile, and pro-/anti-inflammatory ratio than the controls, with ADHD females showing a higher TNF-α and pro-/anti-inflammatory ratio than the control females and ADHD males showing higher levels of IL-1β and IL-6, TNF-α, and M1 profile than the control males. Immune dysregulation appeared to be different for both neurodevelopmental disorders in adolescence.

Physical symptoms and brain morphology: a population neuroimaging study in 12,286 pre-adolescents

Physical symptoms, also known as somatic symptoms, are those for which medical examinations do not reveal a sufficient underlying root cause (e.g., pain and fatigue). The extant literature of the neurobiological underpinnings of physical symptoms is largely inconsistent and primarily comprises of (clinical) case-control studies with small sample sizes. In this cross-sectional study, we studied the association between dimensionally measured physical symptoms and brain morphology in pre-adolescents from two population-based cohorts; the Generation R Study (n = 2649, 10.1 ± 0.6 years old) and ABCD Study (n = 9637, 9.9 ± 0.6 years old). Physical symptoms were evaluated using continuous scores from the somatic complaints syndrome scale from the parent-reported Child Behavior Checklist (CBCL). High-resolution structural magnetic resonance imaging (MRI) was collected using 3-Tesla MRI systems. Linear regression models were fitted for global brain metrics (cortical and subcortical grey matter and total white matter volume) and surface-based vertex-wise measures (surface area and cortical thickness). Results were meta-analysed. Symptoms of anxiety/depression were studied as a contrasting comorbidity. In the meta-analyses across cohorts, we found negative associations between physical symptoms and surface area in the (i) left hemisphere; in the lateral orbitofrontal cortex and pars triangularis and (ii) right hemisphere; in the pars triangularis, the pars orbitalis, insula, middle temporal gyrus and caudal anterior cingulate cortex. However, only a subset of regions (left lateral orbitofrontal cortex and right pars triangularis) were specifically associated with physical symptoms, while others were also related to symptoms of anxiety/depression. No significant associations were observed for cortical thickness. This study in preadolescents, the most representative and well-powered to date, showed that more physical symptoms are modestly related to less surface area of the prefrontal cortex mostly. While these effects are subtle, future prospective research is warranted to understand the longitudinal relationship of physical symptoms and brain changes over time. Particularly, to elucidate whether physical symptoms are a potential cause or consequence of distinct neurodevelopmental trajectories.

Brain structure and function link to variation in biobehavioral dimensions across the psychopathological continuum

In line with the Research Domain Criteria (RDoC) , we set out to investigate the brain basis of psychopathology within a transdiagnostic, dimensional framework. We performed an integrative structural-functional linked independent component analysis to study the relationship between brain measures and a broad set of biobehavioral measures in a sample (n = 295) with both mentally healthy participants and patients with diverse non-psychotic psychiatric disorders (i.e. mood, anxiety, addiction, and neurodevelopmental disorders). To get a more complete understanding of the underlying brain mechanisms, we used gray and white matter measures for brain structure and both resting-state and stress scans for brain function. The results emphasize the importance of the executive control network (ECN) during the functional scans for the understanding of transdiagnostic symptom dimensions. The connectivity between the ECN and the frontoparietal network in the aftermath of stress was correlated with symptom dimensions across both the cognitive and negative valence domains, and also with various other health-related biological and behavioral measures. Finally, we identified a multimodal component that was specifically associated with the diagnosis of autism spectrum disorder (ASD). The involvement of the default mode network, precentral gyrus, and thalamus across the different modalities of this component may reflect the broad functional domains that may be affected in ASD, like theory of mind, motor problems, and sensitivity to sensory stimuli, respectively. Taken together, the findings from our extensive, exploratory analyses emphasize the importance of a dimensional and more integrative approach for getting a better understanding of the brain basis of psychopathology.

The shared white matter developmental trajectory anomalies of attention-deficit/hyperactivity disorder and autism spectrum disorders: A meta-analysis of diffusion tensor imaging studies

Attention-deficit/hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) show common brain area abnormalities, which may contribute to the high shared co-occurrence symptoms and comorbidity of the two disorders. However, neuroanatomic anomalies in neurodevelopmental disorders may change over the course of development, and the developmental variation of these two disorders is unclear. Our study conducted a systematic literature search of PubMed, Web of Science, and EMBASE databases to identify disorder-shared abnormalities of white matter (WM) from childhood to adulthood in ADHD and ASD. 28 ADHD and 23 ASD datasets were included in this meta-analysis and were analysed by AES-SDM to detect differences in fractional anisotropy in patients compared to typically developing individuals. Our main findings reveal the variable WM developmental trajectories in ADHD and ASD respectively, and the two disorders showed overlapping corpus callosum tract abnormalities in their development from children to adults. Furthermore, the overlapping abnormalities of the corpus callosum tract increased with age, which may be related to their gradually increasing shared symptoms and comorbidity in these two disorders.

Predictors of probable attention deficit hyperactivity disorder in elderly patients with mild cognitive impairment visiting a memory clinic

Aim

Characteristics of attention deficit hyperactivity disorder (ADHD) that persist into old age are often confused with symptoms of mild cognitive impairment (MCI), and the actual rate of probable ADHD in people with MCI is unknown. This study estimated the proportion of MCI patients with probable ADHD and investigated the factors to identify MCI patients with probable ADHD.

Methods

We recruited 36 elderly patients (11 males, 25 females, mean age 72.4 ± 7.6 years) who met the MCI criteria. The MCI patients were classified as those with [MCI/ADHD (+)] and without [MCI/ADHD (-)] probable ADHD, according to the Wender Utah Rating Scale scores. The autism features, inattention, and hyperactivity features during childhood and current periods, estimated intelligence quotient, and demographic data were compared between the groups. Multiple logistic regression analysis was performed to identify factors of MCI/ADHD (+) patients.

Results

Nine (25.0%) and 27 patients were added into the MCI/ADHD (+) and MCI/ADHD (-) groups, respectively. The MCI/ADHD (+) group mostly comprised men, those who visited the clinic at a younger age, had more years of schooling, and had strong autism spectrum disorder tendencies. Multiple logistic regression analysis indicated male sex and current hyperactivity as significant predictors of probable ADHD in MCI patients.

Conclusion

A quarter of the patients with MCI had probable ADHD. Male sex and hyperactivity at the time of MCI diagnosis might help in predicting probable ADHD in MCI patients. However, these results were obtained from a single-center, small-case study and should be confirmed via longitudinal studies with a large number of cases.

16p11.2 deletion mice exhibit compromised fronto-temporal connectivity, GABAergic dysfunction, and enhanced attentional ability

Autism spectrum disorders are more common in males, and have a substantial genetic component. Chromosomal 16p11.2 deletions in particular carry strong genetic risk for autism, yet their neurobiological impact is poorly characterised, particularly at the integrated systems level. Here we show that mice reproducing this deletion (16p11.2 DEL mice) have reduced GABAergic interneuron gene expression (decreased parvalbumin mRNA in orbitofrontal cortex, and male-specific decreases in Gad67 mRNA in parietal and insular cortex and medial septum). Metabolic activity was increased in medial septum, and in its efferent targets: mammillary body and (males only) subiculum. Functional connectivity was altered between orbitofrontal, insular and auditory cortex, and between septum and hippocampus/subiculum. Consistent with this circuit dysfunction, 16p11.2 DEL mice showed reduced prepulse inhibition, but enhanced performance in the continuous performance test of attentional ability. Level 1 autistic individuals show similarly heightened performance in the equivalent human test, also associated with parietal, insular-orbitofrontal and septo-subicular dysfunction. The data implicate cortical and septal GABAergic dysfunction, and resulting connectivity changes, as the cause of pre-attentional and attentional changes in autism.

A deep connectome learning network using graph convolution for connectome-disease association study

Multivariate analysis approaches provide insights into the identification of phenotype associations in brain connectome data. In recent years, deep learning methods including convolutional neural network (CNN) and graph neural network (GNN), have shifted the development of connectome-wide association studies (CWAS) and made breakthroughs for connectome representation learning by leveraging deep embedded features. However, most existing studies remain limited by potentially ignoring the exploration of region-specific features, which play a key role in distinguishing brain disorders with high intra-class variations, such as autism spectrum disorder (ASD), and attention deficit hyperactivity disorder (ADHD). Here, we propose a multivariate distance-based connectome network (MDCN) that addresses the local specificity problem by efficient parcellation-wise learning, as well as associating population and parcellation dependencies to map individual differences. The approach incorporating an explainable method, parcellation-wise gradient and class activation map (p-GradCAM), is feasible for identifying individual patterns of interest and pinpointing connectome associations with diseases. We demonstrate the utility of our method on two largely aggregated multicenter public datasets by distinguishing ASD and ADHD from healthy controls and assessing their associations with underlying diseases. Extensive experiments have demonstrated the superiority of MDCN in classification and interpretation, where MDCN outperformed competitive state-of-the-art methods and achieved a high proportion of overlap with previous findings. As a CWAS-guided deep learning method, our proposed MDCN framework may narrow the bridge between deep learning and CWAS approaches, and provide new insights for connectome-wide association studies.

Prevalence and treatment of mental, behavioral, and developmental disorders in children with co-occurring autism spectrum disorder and attention-deficit/hyperactivity disorder: A population-based study

There is a lack of nationally representative studies examining the co-occurrence of autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD) in children. This study examines comorbid mental, behavioral, and developmental disorders (MBDDs) and associated treatment modalities for children with co-occurring ASD and ADHD. Cross-sectional analyses were conducted using data from the pooled 2016-2018 National Survey of Children's Health (sample n = 102,341). Nationally representative prevalences were estimated for sociodemographic variables, comorbidities, psychotropic medication, and behavioral treatment. We assessed multivariable associations between co-occurring ASD + ADHD and MBDDs, use of psychotropic medication, and receipt of behavioral treatment after adjustment for sociodemographic confounders. Compared to children with ASD without co-occurring ADHD, children with ASD + ADHD had higher prevalence of most MBDDs, including anxiety (AOR 4.03 [95% CI 2.77, 4.87]), depression (AOR 3.08 [95% CI 1.77, 5.36]), behavior or conduct problems (AOR 4.06 [95% CI 2.72, 6.06]), and other mental health conditions. Similarly, compared to children with ADHD without ASD, children with ASD + ADHD had higher odds of anxiety (AOR 3.49 [95% CI 2.65, 4.61]), depression (AOR 1.67 [95% CI 1.21, 2.29]), behavior or conduct problems (AOR 2.31 [95% CI 1.68, 3.17]), and other mental health conditions. Children with ASD + ADHD were significantly more likely to take psychotropic medication than children with ASD without ADHD. Among children with ASD + ADHD, males had higher odds of receiving behavioral treatment, whereas older children and adolescents were more likely to take psychotropic medication. A multidisciplinary approach is necessary to support the complex needs of these children.

Executive function profiles of preschool children with autism spectrum disorder and attention-deficit/hyperactivity disorder: A systematic review

Background

Autism Spectrum Disorder (ASD) and Attention-Deficit/Hyperactivity Disorder (ADHD) are both associated with differences in Executive Functioning (EF). There is lack of clarity around the specificity or overlap of EF differences in early childhood when both disorders are first emerging.

Method

This systematic review aims to delineate preschool EF profiles by examining studies comparing the EF profiles of children with and without ASD or ADHD. Five electronic databases were systematically searched (last search in May 2022) to identify published, quantitative studies of global and specific EF (Inhibition, Shifting, Working Memory (WM), Planning and Attentional Control), comparing children aged 2-6 with a diagnosis of ASD or ADHD to peers without ASD or ADHD.

Results

Thirty-one empirical studies (10 ADHD and 21 ASD studies) met criteria for inclusion. EF profiles in preschool ASD were characterised by consistent Shifting, and, in most cases, Inhibition impairments. ADHD studies consistently reported impairments in Inhibition and Planning, and in most cases WM. Findings with regards to sustained Attention and Shifting in ADHD and WM and Planning in ASD were mixed.

Conclusions

Overall, current evidence indicates overlap but also some specificity in EF impairments in preschool ASD and ADHD. There were differences in the degree to which individual domains were impaired, with Shifting more consistently impaired in ASD, and Inhibition, WM and Planning in ADHD. Methodological issues and differences in methods of outcome measurement could potentially underlie mixed findings, as informant-based measures revealed more robust EF impairments than laboratory-based tasks.

Transdiagnostic profiles of behaviour and communication relate to academic and socioemotional functioning and neural white matter organisation

BACKGROUND

Behavioural and language difficulties co-occur in multiple neurodevelopmental conditions. Our understanding of these problems has arguably been slowed by an overreliance on study designs that compare diagnostic groups and fail to capture the overlap across different neurodevelopmental disorders and the heterogeneity within them.

METHODS

We recruited a large transdiagnostic cohort of children with complex needs (N = 805) to identify distinct subgroups of children with common profiles of behavioural and language strengths and difficulties. We then investigated whether and how these data-driven groupings could be distinguished from a comparison sample (N = 158) on measures of academic and socioemotional functioning and patterns of global and local white matter connectome organisation. Academic skills were assessed via standardised measures of reading and maths. Socioemotional functioning was captured by the parent-rated version of the Strengths and Difficulties Questionnaire.

RESULTS

We identified three distinct subgroups of children, each with different levels of difficulties in structural language, pragmatic communication, and hot and cool executive functions. All three subgroups struggled with academic and socioemotional skills relative to the comparison sample, potentially representing three alternative but related developmental pathways to difficulties in these areas. The children with the weakest language skills had the most widespread difficulties with learning, whereas those with more pronounced difficulties with hot executive skills experienced the most severe difficulties in the socioemotional domain. Each data-driven subgroup could be distinguished from the comparison sample based on both shared and subgroup-unique patterns of neural white matter organisation. Children with the most pronounced deficits in language, cool executive, or hot executive function were differentiated from the comparison sample by altered connectivity in predominantly thalamocortical, temporal-parietal-occipital, and frontostriatal circuits, respectively.

CONCLUSIONS

These findings advance our understanding of commonly co-morbid behavioural and language problems and their relationship to behavioural outcomes and neurobiological substrates.

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.

Features and effects of computer-based games on cognitive impairments in children with autism spectrum disorder: an evidence-based systematic literature review

INTRODUCTION

Children with Autism Spectrum Disorder (ASD) have different cognitive and intelligence profiles than typical developing individuals. Some of these children need cognitive rehabilitation. This study's main purpose is to provide a systematic review about applying computerized cognitive games for autistic children and to determine the effectiveness of such interventions.

MATERIAL AND METHODS

A thorough search of the ISI Web of Science, Medline (through PubMed), Scopus, IEEE Xplore, and APA PsycInfo databases was performed for articles published from inception to May 17, 2022.

RESULTS

Of 1746 papers, 28 studies were found to be eligible in this systematic review. Fifteen studies (53.57%) compared a Control Group (CG) with Experimental Groups (EGs), while 13 papers (46.42%) evaluated only the impact of the applied intervention in an experimental group. Major domains of cognitive functions are divided into five main categories: 1. Executive functions, 2. Social cognition/emotions, 3. Attention/concentration, 4. Learning and memory, and 5. Language. In 42.85% (12 studies) of the screened papers, social cognition and emotions were assessed after cognitive rehabilitation. The highest rate of effects reported by studies were related to social cognition enhancement. Of the total number of included studies, 17 studies reported a positive effect at all scales, of which nine were quasi-experimental, and seven were fully experimental.

CONCLUSION

Using suitable computerized game-based solutions could enhance cognition indexes in autistic children. Hence, further investigation is needed to determine the real effectiveness of these novel technologies.

Social and Nonsocial Autism Symptom Domains in Children and Adolescents with Autism Spectrum Disorder and Attention-Deficit/Hyperactivity Disorder: Insights into Their Symptomatological Interplay

INTRODUCTION

Autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD) share overlapping symptomatology, particularly with regard to social impairments (including peer relationship difficulties), and they frequently co-occur. However, the nature of their co-occurrence remains unclear. Therefore, the current study aimed to examine the nature of the transdiagnostic link between ASD and ADHD from a symptomatological point of view measured with the Autism Diagnostic Observation Schedule (ADOS Module 3) and the Autism Diagnostic Interview-Revised (ADI-R).

METHODS

We analyzed the social and nonsocial ASD symptom domain scores from both diagnostic instruments in 4 clinically referred groups (i.e., ASD, ADHD, ASD + ADHD, and no psychiatric diagnosis) without other co-occurring mental disorders using a two-by-two full-factorial MANOVA design with the factors ASD (yes/no) and ADHD (yes/no).

RESULTS

We found no ASD by ADHD interaction effects across all symptom domain scores of ADOS and ADI-R, except for ADOS imagination/creativity. There were only main effects of the factor ASD but no main effects of ADHD. Follow-up contrasts showed that exclusively, ASD had an impact on the measured symptomatology in case of co-occurring ASD + ADHD.

CONCLUSION

Overall, the results support an additive model of the symptomatology across areas of communication, social interaction, and stereotyped behaviors and restricted interests in case of the co-occurrence of ASD and ADHD when assessed with ADOS/ADI-R. Thus, one can assume that the phenotypic overlap of ASD + ADHD may be less complicated than suspected - at least with regard to ASD symptomatology - and that in the presence of ADHD, ASD symptomatology is generally well measurable with best-practice diagnostic instruments.

The translational genetics of ADHD and related phenotypes in model organisms

Attention-deficit/hyperactivity disorder (ADHD) is a highly prevalent neurodevelopmental disorder resulting from the interaction between genetic and environmental risk factors. It is well known that ADHD co-occurs frequently with other psychiatric disorders due, in part, to shared genetics factors. Although many studies have contributed to delineate the genetic landscape of psychiatric disorders, their specific molecular underpinnings are still not fully understood. The use of animal models can help us to understand the role of specific genes and environmental stimuli-induced epigenetic modifications in the pathogenesis of ADHD and its comorbidities. The aim of this review is to provide an overview on the functional work performed in rodents, zebrafish and fruit fly and highlight the generated insights into the biology of ADHD, with a special focus on genetics and epigenetics. We also describe the behavioral tests that are available to study ADHD-relevant phenotypes and comorbid traits in these models. Furthermore, we have searched for new models to study ADHD and its comorbidities, which can be useful to test potential pharmacological treatments.

Parents' differential susceptibility to a "micro" parenting intervention: Rationale and study protocol for a randomized controlled microtrial

BACKGROUND

Given evidence that parenting can influence children's development, parenting interventions are often the strategy of choice when it comes to treating children's disruptive behavior problems-or preventing problems from developing in the first place. What remains under appreciated, however, is that some parents appear to be more responsive to interventions to foster skilled parenting than others. Notable in this regard is the ever-increasing observational and, perhaps more importantly, experimental evidence indicating that some children prove more susceptible to parenting interventions than others. So, while the experimental evidence clearly indicates that "susceptibility factors" which children carry seem to affect their likelihood of benefiting from a parenting intervention (and other environmental influences), what remains unclear is why the parenting interventions in question prove more effective in changing the behavior of some parents more than others. Could it be as a result of their own parental characteristics?

OBJECTIVE

The Parfective Microtrial in a randomized controlled microtrial, in which we focus not just on parental (and child) responsiveness but also on an underlying physiological mechanism hypothesized to contribute to heightened susceptibility to parenting interventions.

METHODS

Participants are 120 families, with children aged 4-5 years, recruited from the community. Of these, 60 are randomly assigned to the "micro" intervention condition (i.e., immediate positive parenting feedback) and 60 families to the care-as-usual control condition. Assessments in both conditions will be conducted at baseline (pretest), after 2 weeks (posttest), and after 4 weeks (follow-up). Primary outcomes are the hypothesized moderating effects of physiology on the anticipated "micro" intervention effect (i.e., decrease in negative parenting behavior and/or increase in positive parenting behavior). Secondary outcomes are the observed (changes in) child behavior in response to the parenting intervention, such that those parents and children-in the same family-who manifest these physiological attributes will prove most susceptible to the beneficial effects of the intervention.

TRIAL REGISTRATION

This study protocol is registered at ClinicalTrials.gov (NCT05539170).

Infant excitation/inhibition balance interacts with executive attention to predict autistic traits in childhood

BACKGROUND

Autism is proposed to be characterised by an atypical balance of cortical excitation and inhibition (E/I). However, most studies have examined E/I alterations in older autistic individuals, meaning that findings could in part reflect homeostatic compensation. To assess the directionality of effects, it is necessary to examine alterations in E/I balance early in the lifespan before symptom emergence. Recent explanatory frameworks have argued that it is also necessary to consider how early risk features interact with later developing modifier factors to predict autism outcomes.

METHOD

We indexed E/I balance in early infancy by extracting the aperiodic exponent of the slope of the electroencephalogram (EEG) power spectrum ('1/f'). To validate our index of E/I balance, we tested for differences in the aperiodic exponent in 10-month-old infants with (n = 22) and without (n = 27) neurofibromatosis type 1 (NF1), a condition thought to be characterised by alterations to cortical inhibition. We then tested for E/I alterations in a larger heterogeneous longitudinal cohort of infants with and without a family history of neurodevelopmental conditions (n = 150) who had been followed to early childhood. We tested the relevance of alterations in E/I balance and our proposed modifier, executive attention, by assessing whether associations between 10-month aperiodic slope and 36-month neurodevelopmental traits were moderated by 24-month executive attention. Analyses adjusted for age at EEG assessment, sex and number of EEG trials.

RESULTS

Infants with NF1 were characterised by a higher aperiodic exponent, indicative of greater inhibition, supporting our infant measure of E/I. Longitudinal analyses showed a significant interaction between aperiodic slope and executive attention, such that higher aperiodic exponents predicted greater autistic traits in childhood, but only in infants who also had weaker executive functioning abilities.

LIMITATIONS

The current study relied on parent report of infant executive functioning-type abilities; future work is required to replicate effects with objective measures of cognition.

CONCLUSIONS

Results suggest alterations in E/I balance are on the developmental pathway to autism outcomes, and that higher executive functioning abilities may buffer the impact of early cortical atypicalities, consistent with proposals that stronger executive functioning abilities may modify the impact of a wide range of risk factors.

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

In this study, we examined autism spectrum disorder (ASD) symptoms in adults with attention-deficit hyperactivity disorder (ADHD) in comparison with normal controls using the Autism Diagnostic Observation Schedule, Second Edition (ADOS-2). Sixty-three adults with ADHD (mean age, 35.3 years; 38 men) and 31 controls (mean age, 38.7 years; 17 men) completed Module 4 of the ADOS-2, Autism Spectrum Quotient, Conners' Adult ADHD Rating Scale, and Wechsler Adult Intelligence Scale, Third Edition. Adults with ADHD were not clinically diagnosed with ASD, and their ADHD diagnosis was based on the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition criteria. Between-group comparisons on the scoring patterns revealed significant ASD symptoms present in adults with ADHD, which was congruent with our previous study. Further, item level and correlation analyses showed the possibility that ASD symptoms in adult ADHD comprised of two distinct mechanisms, one qualitatively similar to ASD and the other arising from ADHD characteristics, highlighting the complex nature of ADHD-ASD symptom overlaps.

Characterizing the ASD-ADHD phenotype: measurement structure and invariance in a clinical sample

BACKGROUND

Autism Spectrum Disorder (ASD) and Attention Deficit Hyperactivity Disorder (ADHD) have considerable overlap, supporting the need for a dimensional framework that examines neurodevelopmental domains which cross traditional diagnostic boundaries. In the following study, we use factor analysis to deconstruct the ASD-ADHD phenotype into its underlying phenotypic domains and test for measurement invariance across adaptive functioning, age, gender and ASD/ADHD clinical diagnoses.

METHODS

Participants included children and youth (aged 3-20 years) with a clinical diagnosis of ASD (n = 727) or ADHD (n = 770) for a total of 1,497 participants. Parents of these children completed the Social Communication Questionnaire (SCQ), a measure of autism symptoms, and the Strengths and Weaknesses of ADHD and Normal Behaviour (SWAN) questionnaire, a measure of ADHD symptoms. An exploratory factor analysis (EFA) was performed on combined SCQ and SWAN items. This was followed by a confirmatory factor analysis (CFA) and tests of measurement invariance.

RESULTS

EFA revealed a four-factor solution (inattention, hyperactivity/impulsivity, social-communication, and restricted, repetitive, behaviours and interests (RRBI)) and a CFA confirmed good model fit. This solution also showed good model fit across subgroups of interest.

CONCLUSIONS

Our study shows that a combined ASD-ADHD phenotype is characterized by two latent ASD domains (social communication and RRBIs) and two latent ADHD domains (inattention and hyperactivity/impulsivity). We established measurement invariance of the derived measurement model across adaptive functioning, age, gender and ASD/ADHD diagnoses.

Omar ZT, Segun E, Evbayekha EO, Abolurin A, Egberuare EO, Ezegbe HC, Adegbosin A, Adedeji AG, Angaye EG, Izundu IC, Oyelade BO. Impact of Adverse Childhood Experiences on Resilience and School Success in Individuals With Autism Spectrum Disorder and Attention-Deficit Hyperactivity Disorder

Adolescents with emotional and behavioral disorders face known academic challenges and poor life outcomes. It was imperative to explore and find if the new diagnostic criterion for diagnosing autism profoundly affects educational outcomes and resilience in individuals diagnosed with co-occurring autism spectrum disorder (ASD) and attention-deficit hyperactivity disorder (ADHD). The literature is robust on the impact of adverse childhood experiences (ACEs) on educational outcomes and resilience in adolescents with no history of disability. Still, there remains a dearth of literature explaining, with no ambiguity, the complex relationships between ACEs and resilience, school engagement, and success in individuals with co-occurring ASD and ADHD. This study reviews the existing scholarships on the topic. The significance of this review is that it informs healthcare providers, rehabilitation counselors, and educators about the need for early identification of individuals with ASD and ADHD with a background in ACEs. This will enable interventions early enough to ensure they are more resilient and can obtain improved success in school-related and outside-school activities and eventually improved quality of life.

Differences in white matter segments in autistic males, non-autistic siblings, and non-autistic participants: An intermediate phenotype approach

LAY ABSTRACT

White matter is the neural pathway that connects neurons in different brain regions. Although research has shown white matter differences between autistic and non-autistic people, little is known about the properties of white matter in non-autistic siblings. In addition, past studies often focused on the whole neural tracts; it is unclear where differences exist in specific segments of the tracts. This study identified neural segments that differed between autistic people, their non-autistic siblings, and the age- and non-autistic people. We found altered segments within the tracts connected to anterior brain regions corresponding to several higher cognitive functions (e.g. executive functions) in autistic people and non-autistic siblings. Segments connecting to regions for social cognition and Theory of Mind were altered only in autistic people, explaining a large portion of autistic traits and may serve as neuroimaging markers. Segments within the tracts associated with fewer autistic traits or connecting brain regions for diverse highly integrated functions showed compensatory increases in the microstructural properties in non-autistic siblings. Our findings suggest that differential white matter segments that are shared between autistic people and non-autistic siblings may serve as potential "intermediate phenotypes"-biological or neuropsychological characteristics in the causal link between genetics and symptoms-of autism. These findings shed light on a promising neuroimaging model to refine the intermediate phenotype of autism which may facilitate further identification of the genetic and biological bases of autism. Future research exploring links between compensatory segments and neurocognitive strengths in non-autistic siblings may help understand brain adaptation to autism.

Diagnostic and Therapeutic Challenges of Comorbid ASD, ADHD and Psychosis: A Case Report

Autism Spectrum Disorder (ASD) and attention deficit hyperactivity disorder (ADHD) comorbidity is common in clinical practice and it seems to be related to shared etiological mechanisms and genetic susceptibility. Moreover, occurrence of psychosis can further complicate these complex clinical pictures. Here, we discuss the case of a nine-years-old boy presenting with an episode of abnormal sustained posture of the upper limbs, resembling dystonia, at the age of 3. At this time, auditory and visual hallucinations, as well as obsessive thoughts and attentional lability were also present and a diagnosis of "Early onset psychosis" was initially made. Due to the worsening of clinical picture, several hospitalizations were necessary and pharmacological treatment with carbamazepine, risperidone and aripiprazole was carried out. Extensive clinic evaluation revealed a past medical and personal history of toe walking, weak social skills and stereotyped behavior observed and ADOS-2 Module 2 administration revealed severe Autism scores. Moreover, signs of attention and hyperactivity were consistent with ADHD diagnosis. This work highlights the importance of a complete diagnostic assessment in patients with complex presentation, suggesting the possible overlap diagnosis of ADHD and Autism even in presence of psychotic-like symptoms.

Evidence towards a continuum of impairment across neurodevelopmental disorders from basic ocular-motor tasks

Findings of genetic overlap between Schizophrenia, Attention-Deficit/Hyperactivity Disorder (ADHD) and Autism Spectrum Disorder (ASD) contributed to a renewed conceptualization of these disorders as laying on a continuum based on aetiological, pathophysiological and neurodevelopmental features. Given that cognitive impairments are core to their pathophysiology, we compared patients with schizophrenia, ADHD, ASD, and controls on ocular-motor and manual-motor tasks, challenging crucial cognitive processes. Group comparisons revealed inhibition deficits common to all disorders, increased intra-subject variability in schizophrenia and, to a lesser extent, ADHD as well as slowed processing in schizophrenia. Patterns of deviancies from controls exhibited strong correlations, along with differences that posited schizophrenia as the most impaired group, followed by ASD and ADHD. While vector correlations point towards a common neurodevelopmental continuum of impairment, vector levels suggest differences in the severity of such impairment. These findings argue towards a dimensional approach to Neurodevelopmental Disorders' pathophysiological mechanisms.

Identification of shared and differentiating genetic architecture for autism spectrum disorder, attention-deficit hyperactivity disorder and case subgroups

Attention-deficit hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) are highly heritable neurodevelopmental conditions, with considerable overlap in their genetic etiology. We dissected their shared and distinct genetic etiology by cross-disorder analyses of large datasets. We identified seven loci shared by the disorders and five loci differentiating them. All five differentiating loci showed opposite allelic directions in the two disorders and significant associations with other traits, including educational attainment, neuroticism and regional brain volume. Integration with brain transcriptome data enabled us to identify and prioritize several significantly associated genes. The shared genomic fraction contributing to both disorders was strongly correlated with other psychiatric phenotypes, whereas the differentiating portion was correlated most strongly with cognitive traits. Additional analyses revealed that individuals diagnosed with both ASD and ADHD were double-loaded with genetic predispositions for both disorders and showed distinctive patterns of genetic association with other traits compared with the ASD-only and ADHD-only subgroups. These results provide insights into the biological foundation of the development of one or both conditions and of the factors driving psychopathology discriminatively toward either ADHD or ASD.

Visual search in neurodevelopmental disorders: evidence towards a continuum of impairment

Disorders with neurodevelopmental aetiology such as Attention-Deficit/Hyperactivity Disorder (ADHD), Autism Spectrum Disorder (ASD) and Schizophrenia share commonalities at many levels of investigation despite phenotypic differences. Evidence of genetic overlap has led to the concept of a continuum of neurodevelopmental impairment along which these disorders can be positioned in aetiological, pathophysiological and developmental features. This concept requires their simultaneous comparison at different levels, which has not been accomplished so far. Given that cognitive impairments are core to the pathophysiology of these disorders, we provide for the first time differentiated head-to-head comparisons in a complex cognitive function, visual search, decomposing the task with eye movement-based process analyses. N = 103 late-adolescents with schizophrenia, ADHD, ASD and healthy controls took a serial visual search task, while their eye movements were recorded. Patients with schizophrenia presented the greatest level of impairment across different phases of search, followed by patients with ADHD, who shared with patients with schizophrenia elevated intra-subject variability in the pre-search stage. ASD was the least impaired group, but similar to schizophrenia in post-search processes and to schizophrenia and ADHD in pre-search processes and fixation duration while scanning the items. Importantly, the profiles of deviancy from controls were highly correlated between all three clinical groups, in line with the continuum idea. Findings suggest the existence of one common neurodevelopmental continuum of performance for the three disorders, while quantitative differences appear in the level of impairment. Given the relevance of cognitive impairments in these three disorders, we argue in favour of overlapping pathophysiological mechanisms.

The changing faces of autism: The fluctuating international diagnostic criteria and the resulting inclusion and exclusion-A Norwegian perspective

The common understanding of autism spectrum disorders (ASD) has gone through a number of permutations since the first description in 1943. Throughout these shifting understandings, there have been a number of behaviors and diagnostic criteria associated with the condition, many of which are missing in the most recent classifications. The rates of diagnoses of autism have increased greatly. However, there is no reason to think there has been any change in occurrence over the last 70 years, suggesting rather an increase in our knowledge and awareness. Autism has been the subject of several misapprehensions and misrepresentations throughout history. This might be due to heterogeneity of the cases. In addition, the diagnosing of autism spectrum disorders is mainly based on observation and behavioral interpretation, and thus dependent on subjective perceptions of the clinicians themselves. This current scoping review article intends to provide a view on the evolution of the concept of autism and the current stance within Norwegian scholarship, and how it is shaped by international discourses and cultural diversities Such changing concepts especially impacts people with the diagnosis, as it can affect their access to social services, as well as their self-identification as people with ASD.

Alpha oscillatory activity during attentional control in children with Autism Spectrum Disorder (ASD), Attention-Deficit/Hyperactivity Disorder (ADHD), and ASD+ADHD

BACKGROUND

Autism Spectrum Disorder (ASD) and Attention-Deficit/Hyperactivity Disorder (ADHD) share impairments in top-down and bottom-up modulation of attention. However, it is not yet well understood if co-occurrence of ASD and ADHD reflects a distinct or additive profile of attention deficits. We aimed to characterise alpha oscillatory activity (stimulus-locked alpha desynchronisation and prestimulus alpha) as an index of integration of top-down and bottom-up attentional processes in ASD and ADHD.

METHODS

Children with ASD, ADHD, comorbid ASD+ADHD, and typically-developing children completed a fixed-choice reaction-time task ('Fast task') while neurophysiological activity was recorded. Outcome measures were derived from source-decomposed neurophysiological data. Main measures of interest were prestimulus alpha power and alpha desynchronisation (difference between poststimulus and prestimulus alpha). Poststimulus activity linked to attention allocation (P1, P3), attentional control (N2), and cognitive control (theta synchronisation, 100-600 ms) was also examined. ANOVA was used to test differences across diagnostics groups on these measures. Spearman's correlations were used to investigate the relationship between attentional control processes (alpha oscillations), central executive functions (theta synchronisation), early visual processing (P1), and behavioural performance.

RESULTS

Children with ADHD (ADHD and ASD+ADHD) showed attenuated alpha desynchronisation, indicating poor integration of top-down and bottom-up attentional processes. Children with ADHD showed reduced N2 and P3 amplitudes, while children with ASD (ASD and ASD+ADHD) showed greater N2 amplitude, indicating atypical attentional control and attention allocation across ASD and ADHD. In the ASD group, prestimulus alpha and theta synchronisation were negatively correlated, and alpha desynchronisation and theta synchronisation were positively correlated, suggesting an atypical association between attentional control processes and executive functions.

CONCLUSIONS

ASD and ADHD are associated with disorder-specific impairments, while children with ASD+ADHD overall presented an additive profile with attentional deficits of both disorders. Importantly, these findings may inform the improvement of transdiagnostic procedures and optimisation of personalised intervention approaches.