Journal of Neurodevelopmental Disorders

IntroductionFragile X Syndrome (FXS), caused by Fmr1 mutations, is linked to cognitive and behavioral differences, including altered social interactions. Most mouse studies focus on adults, despite human research showing critical developmental changes in childhood and adolescence. We examined social behavior in juvenile male and female Fmr1 knockout (KO) mice as well as heterozygous (HET) females. We further assessed cortical activity in KO females to better understand early phenotypes. MethodsJuvenile mice of both sexes and genotypes were paired in same-sex, novel dyads for 10-minute interactions. Key social behaviors such as head, anogenital, and body sniffing, and physical touch, as well as distance travelled, were analyzed with a marker-less tracking software. Frontal-parietal EEG recordings were collected from wild-type (WT) and KO females in home cage and social contexts to analyze power spectra across frequency bands. ResultsHET and KO females engaged in more frequent but shorter interaction events compared to WT females, with HET females showing the highest counts. Males displayed similar trends when comparing KO and WT. Males engaged in overall higher interaction events than females. EEG analyses revealed altered oscillatory activity in KO females compared to WT females, especially within theta, alpha, and beta bands, most prominently during the early interaction phase. Locomotor activity correlated weakly with head/anogenital sniffing but more strongly with body sniffing and touch. DiscussionThese findings suggest that Fmr1-related differences in juvenile social behavior are sex-dependent and associated with cortical oscillatory changes. Characterizing these early phenotypes in both sexes allows us to further understand FXS development and informs potential routes for early intervention. Key PointsO_LIFragile X Syndrome (FXS), the leading inherited cause of autism, is associated with disruptions in social behavior. C_LIO_LIWhile social phenotypes are relatively well described in adult mouse models of FXS, juvenile manifestations remain poorly understood. C_LIO_LISocial behavior was assessed in juvenile male and female Fmr1 knockout (KO), heterozygous (HET, female only), and wildtype (WT) mice, and frontal-parietal EEG recordings were collected from WT and KO females. C_LIO_LIHET and KO females exhibited more frequent but shorter social interactions than WT females, with HET showing the greatest number of events. Males showed similar patterns when comparing KO and WT. Males engaged in higher overall interaction events than females. EEG recordings revealed altered oscillatory activity in KO compared to WT females, most pronounced during the early phase of social encounter. C_LIO_LIThese findings reveal sex- and genotype-dependent differences in juvenile social behavior and cortical activity, highlighting the importance of studying juvenile development in FXS. C_LI

Attention-deficit/hyperactivity disorder (ADHD) is a neurodevelopmental disorder, with symptoms that remit or persist over time. Biological mechanisms underlying symptom change remain poorly understood, though epigenetic processes, like DNA methylation (DNAm), may serve as dynamic biomarkers of clinical outcomes. We examined change in DNAm in children and adolescents with and without ADHD, including differences between remitted and persistent ADHD. MethodsWe analyzed 219 saliva samples from 94 participants (aged 9.5-14.5 years) attending 2 to 3 waves of NICAP. DNAm was profiled using the Infinium MethylationEPIC BeadChip. Linear mixed models adjusted for age, sex, medication, batch and cell-proportion assessed longitudinal change. Comparisons included (1) all ADHD cases versus controls, (2) persistent or remitted ADHD versus controls, and (3) persistent versus remitted ADHD. False discovery rate correction controlled for multiple testing (FDR p<0.05). ResultsNo CpGs were statistically different between ADHD and controls, after correction. Compared to controls, the average DNAm at 5 sites was statistically different in persistent or remitted ADHD, and methylation of 3 additional CpGs differentially changed over time in persistent ADHD. Remitted differed from persistent ADHD at four CpGs, including cg21443143 (ZFAT), which showed a unique decline over time. Gene enrichment links findings to brain structures and function, though these did not survive multiple testing. ConclusionOur study identified several epigenetic differences between remitted and persistent ADHD outcomes from typical development, and from each other. Given the early stage of this research, our findings warrant further prospective epigenome-wide studies into these diagnostic trajectories.

Autism is a common neurodevelopmental disorder that despite its complex etiology, is marked by deficits in prediction that manifest in a variety of domains including social interactions, communication, and movement. The tendency of individuals with autism to focus on predictable schedules and interests that contain patterns and rules highlights the likely involvement of the cerebellum in this disorder. One candidate-autism gene is contact in associated protein 2 (CNTNAP2), and variants in this gene are associated with sensory deficits and anatomical differences. It is unknown, however, whether this gene directly impacts the brains ability to make and evaluate predictions about future events. The current study was designed to answer this question by training a genetic knockout rat on a rapid speech sound discrimination task. Rats with Cntnap2 knockout (KO) and their littermate wildtype controls (WT) were trained on a validated rapid speech sound discrimination task that contained unpredictable and predictable targets. We found that although both genotype groups learned the task in both unpredictable and predictable conditions, the KO rats responded more often to distractors during training as well as to the target sound during the predictable testing conditions compared to the WT group. There were only minor effects of sex on performance and only in the unpredictable condition. The current results provide preliminary evidence that removal of this candidate-autism gene may interfere with the learning of unpredictable scenarios and enhance reliance on predictability. Future research is needed to probe the neural anatomy and function that drives this effect.

BackgroundAltered patterns of eye-movements during scene exploration, and atypical gaze preferences in social settings, have long been noted as features of the Autism phenotype. While these are typically attributed to differences in social engagement and interests (e.g., preferences for inanimate objects over face stimuli), there are also reports of differential saccade measures to non-social stimuli, raising the possibility that fundamental differences in visuo-sensorimotor processing may be at play. Here, we tested the plasticity of the eye-movement system using a classic saccade-adaptation paradigm to assess whether individuals with ASD make typical adjustments to their eye-movements in response to experimentally introduced errors. Saccade adaptation can be measured in infants as young as 10 months, raising the possibility that such measures could be useful as early neuromarkers of ASD risk. MethodsSaccade amplitudes were measured while children and adults with ASD (N=41) and age-matched typically developing (TD) individuals (N=68) made rapid eye-movements to peripherally presented targets. During adaptation trials, the target was relocated from 20-degrees to 15-degrees from fixation once a saccade to the original target location was initiated, a manipulation that leads to systematic reduction in saccade amplitudes in typical observers. ResultsNeither children nor adults with ASD showed any differences relative to TD peers in their abilities to appropriately adapt saccades in the face of persistently introduced errors. ConclusionsOf the three studies to date of saccade adaptation in ASD, none have shown frank deficits in saccade adaptation. Unlike prior studies, we found no evidence for a slower adaptation rate during the early adaptation phase, and no of evidence greater variance of saccade amplitudes in ASD. In post-hoc analysis, there was evidence for larger primary saccades to non-adapted targets, a finding requiring replication in future work.

BackgroundDifferences in sensory processing are a core feature of autism spectrum disorder. Hyper- and hyporesponsivity to sensory stimuli have historically been conceptualized as separate constructs but may co-occur within individuals. Sensory processing may impact both lower and higher-level cognitive processes; thus, it is crucial to understand the relationships between hyper- and hyporesponsivity within and across modalities, as well as the relationship between sensory processing and other aspects of development in both autistic and typically developing (TD) children. MethodsIn 3-4-year-old children (n=41 autism; n=37 TD), we assessed relationships between sensory hyper- and hyporesponsivity both within and across visual, auditory, touch, and oral sensory modalities as measured by caregiver report. Secondary analyses evaluated relationships between sensory responsivity, social communication, and cognitive abilities. FindingsWe found a positive correlation between sensory hyper- and hyporesponsivity ({rho} = .788, p < .001). These associations persisted within groups and within and across modalities. There are positive associations between sensory responsivity and social interaction, communication, and nonverbal developmental quotient, with associations between sensory responsivity and social communication driven by associations within the autism group. InterpretationThe positive correlations between hyper- and hyporesponsivity both within and across sensory modalities, which we term the "Sensory Paradox," may provide key clues to understanding sensory processing in autism and other neurodevelopmental disorders by pointing towards neural circuit-level mechanisms that may underlie neurodevelopmental conditions. FundingThis study was funded by NIH/NINDS 1R01NS134948-01 (ARL), NIMH T32MH112510 (KDC), the Simons Foundation Autism Research Initiative (Award number 648277, ARL), and the Eagles Autism Foundation (ARL). Research in contextO_ST_ABSEvidence before this studyC_ST_ABSUp to 95% of autistic individuals are impacted by sensory processing differences. Across the full range of the autism spectrum, including individuals with profound ASD and self-advocates who speak publicly on issues of neurodiversity, improving sensory processing challenges is repeatedly noted as a common goal that would improve quality of life. Classical medical evaluation of sensory processing typically focuses on whether the structural pathways for transmission of sensory information are intact. The modulation of sensory information as it traverses these pathways, however, is a field ripe for further understanding. Initial reports have identified both hyper- and hyporesponsivity to sensory stimuli in autism, with some overlap between the two patterns of behavior. Added value of this studyThis study demonstrates the seemingly paradoxical finding that hyper- and hyporesponsivity are strongly positively correlated in both autistic and typically developing toddlers. This positive correlation persists within groups and within individual sensory modalities (sight, sound, touch, and oral), as well as across modalities. Implications of all of the available evidenceThe current findings, taken together with prior literature, support the Sensory Paradox - a framework for understanding sensory processing and the resulting sensory experience of autistic individuals which may also have key implications for a wider variety of neurological, psychiatric, and developmental conditions. Rather than considering hyper- and hyporesponsivity as static and opposing constructs, future work on the neurobiology, diagnosis, and management of sensory processing will benefit from considering the variable and context-dependent nature of sensory processing within individuals.

MotivationAutism spectrum disorder (ASD) has a strong, yet heterogeneous, genetic component. Among the various methods that are being developed to help reveal the underlying molecular aetiology of the disease, one that is gaining popularity is the combination of gene expression and clinical genetic data. For ASD, the SFARI-gene database comprises lists of curated genes in which presumed causative mutations have been identified in patients. In order to predict novel candidate SFARI-genes we built classification models combining differential gene expression data for ASD patients and unaffected individuals with a genes status in the SFARI-gene list. ResultsSFARI-genes were not found to be significantly associated with differential gene expression patterns, nor were they enriched in gene co-expression network modules that had a strong correlation with ASD diagnosis. However, network analysis and machine learning models that incorporate information from the whole gene co-expression network were able to predict novel candidate genes that share features of existing SFARI genes and have support for roles in ASD in the literature. We found a statistically significant bias related to the absolute level of gene expression for existing SFARI genes and their scores. It is essential that this bias be taken into account when studies interpret ASD gene expression data at gene, module and whole-network levels. AvailabilitySource code is available from GitHub (https://doi.org/10.5281/zenodo.4463693) and the accompanying data from The University of Edinburgh DataStore (https://doi.org/10.7488/ds/2980) Contactian.simpson@ed.ac.uk

De novo mutations (DNMs), including germinal and postzygotic mutations (PZMs), are a strong source of causality for Autism Spectrum Disorder (ASD). However, the biological processes involved behind them remain unexplored. Our aim was to detect DNMs (germinal and PZMs) in a Spanish ASD cohort (360 trios) and to explore their role across different biological hierarchies (gene, biological pathway, cell and brain areas) using bioinformatic approaches. For the majority of the analysis, a combined cohort (N=2171 trios) with ASC (Autism Sequencing Consortium) previously published data was created. New plausible candidate genes for ASD such as FMR1 and NFIA were found. In addition, genes harboring PZMs were significantly enriched for miR-137 targets in comparison with germinal DNMs that were enriched in GO terms related to synaptic transmission. The expression pattern of genes with PZMs was restricted to early mid-fetal cortex. In contrast, the analysis of genes with germinal DNMs revealed a spatio-temporal window from early to mid-fetal development stages, with expression in the amygdala, cerebellum, cortex and striatum. These results provide evidence of the pathogenic role of PZMs and suggest the existence of distinct mechanisms between PZMs and germinal DNMs that are influencing ASD risk.

Behavioral copying is a key process in group actions, but it is challenging for individuals with Autism Spectrum Disorder (ASD). We investigated behavioral contagion, or instinctual replication of behaviors, in Krushinky-Molodkina (KM) rats (n=16), a new rodent model for ASD, compared to control Wistar rats (n=15). A randomly chosen healthy Wistar male ("demonstrator rat") was introduced to the homecage of experimental rats ("observers") 10-14 days before the experiments to become a member of the group. For the implementation of the behavioral contagion experiment, we used the IntelliCage system, where rats can live in a group of 5-6 rats and their water visits can be fully controlled. During the experiment, the demonstrator was taken out of IntelliCage for 24 hours of water deprivation and then placed back. As a result, a drinking behavior of the water-deprived demonstrator rat prompted activated behaviors in the whole group. Unlike the Wistar controls, KM observers showed fewer visits to the drinking bottles, particularly lacking inspection visits. The control group, in contrast, exhibited a dynamic, cascade-like visiting of the water corners. The proportion of activated observers in KM rats was significantly lower, as compared to Wistar ones, and they did not mimic other observer rats. KM rats, therefore, displayed an attenuated pattern of behavioral contagion, highlighting social deficits in this ASD model. This study suggests that measuring group dynamics of behavioral contagion in an automated, non-invasive setup offers valuable insights into social behavior in rodents, particularly for studying social deficits in ASD models. HighlightsO_LIThirsty demonstrators triggered an avalanche of observers visits to the water corners C_LIO_LIThe contaged behavior was attenuated in observer KM rats C_LIO_LIBehavioral contagion test provides a new tool for objective, automated phenotyping in rodent models of social deficits C_LI

ObjectiveTo determine how impairments in associative learning in autism spectrum disorder (ASD) relate to intellectual disability (ID) and early-childhood cerebellar hypoplasia. MethodsTrace and long-delay eye blink conditioning (EBC) were performed in 62 children age 11.2 years having: 1) ASD with ID (ASD+ID); 2) ASD without ID (ASD-noID); or 3) typical development (TD). The sub-second timing of conditioned eye-blink responses (CRs) acquired to a tone paired with a corneal air puff was related to brain structure at age 2 years and clinical measures across ages 2-12 years. Because CR timing is influenced strongly by cerebellar function, EBC was used to test hypotheses relating cerebellar hypoplasia to ASD. ResultsChildren with ASD+ID showed early-onset CRs during trace EBC that were related to early-childhood hypoplasia of the cerebellum but not of the cerebral cortex, hippocampus, or amygdala. Children with ASD-noID showed early-onset CRs only during long-delay EBC without cerebellar hypoplasia. Using EBC measures, logistic regression detected ASD with 81% sensitivity and 79% specificity while linear discriminant analysis separated ASD subgroups based on ID but not ASD severity. MRI of additional 2-year-olds with ASD indicated that early-onset CRs during trace EBC revealed ASD+ID more readily than cerebellar hypoplasia, per se. ConclusionsEarly-childhood cerebellar hypoplasia occurs in children with ASD+ID that demonstrate early-onset CRs during trace EBC. Trace EBC reveals the relationship between cerebellar hypoplasia and ASD+ID likely by engaging cerebro-cerebellar circuits involved in intellect. We emphasize that the cerebellum optimizes sensory-motor processing at sub-second intervals, impairments of which may contribute to ID.

Differences in looking to and processing of audiovisual speech have been theorized to contribute to heterogeneity in language ability in autistic children. Differential audiovisual speech processing has been indexed by event-related potentials (ERPs), specifically via amplitude suppression in response to audiovisual versus auditory-only speech, and linked with vocabulary in school-aged children. This study used an intact-group comparison and concurrent correlational design in infant siblings of autistic children (Sibs-Autism) and non-autistic children (Sibs-NA) to determine whether amplitude suppression is (a) present in infancy, (b) different in Sibs-Autism versus Sibs-NA, and (c) related to looking to audiovisual speech and language abilities. We collected EEG data from 54 infants aged 12-18 months (29 Sibs-Autism; 25 Sibs-NA) while they viewed videos of audiovisual and auditory-only speech, as well as eye tracking and language data. We found significant amplitude differences at the N2 ERP component in response to audiovisual versus auditory-only speech but no significant group differences in ERP amplitudes. Associations between looking to audiovisual speech, amplitude effects, and language were moderated by group, chronological age, and biological sex. Our findings suggest that differential audiovisual speech processing is present in 12-18-month-olds and may explain heterogeneity in looking to audiovisual speech and emerging language ability.

Attention-Deficit/Hyperactivity Disorder (ADHD) is a childhood psychiatric disorder often comorbid with disruptive behavior disorders (DBDs). ADHD comorbid with DBDs (ADHD+DBDs) is a complex phenotype with a risk component that can be attributed to common genetic variants. Here we report a large GWAS meta-analysis of ADHD+DBDs based on seven cohorts in total including 3,802 cases and 31,305 controls. Three genome-wide significant loci were identified on chromosomes 1, 7, and 11. A GWAS meta-analysis including a Chinese cohort supported the locus on chromosome 11 to be a strong risk locus for ADHD+DBDs across European and Chinese ancestries (rs7118422, P=3.15x10-10, OR=1.17). This locus was not associated with ADHD without DBDs in a secondary GWAS of 13,583 ADHD cases and 22,314 controls, suggesting that the locus is a specific risk locus for the comorbid phenotype.\n\nWe found a higher SNP heritability for ADHD+DBDs (h2SNP =0.34) when compared to ADHD without DBDs (h2SNP =0.20). Genetic correlations of ADHD+DBDs with aggressive (rg =0.81) and anti-social behaviors (rg=0.82) were high, and polygenic risk score analyses revealed a significant increased burden of variants associated with ADHD and aggression in individuals with ADHD+DBDs compared to ADHD without DBDs. Our results suggests that ADHD+DBDs represent a more severe phenotype with respect to the genetic risk load than ADHD without DBDs, in line with previous studies, and that the risk load to some extent can be explained by variants associated with aggressive behavior.

Executive function cognitive deficits and behavioral issues are implicated in neurodevelopmental disorders such as Autism Spectrum Disorder (ASD), Attention Deficit/Hyperactivity Disorder (ADHD), and affective disorders. The current study enrolled 134 children and adolescents (aged 6-17) who were referred to a specialized service. Participants were categorized into groups based on ADHD, ASD, and affective disorders to conduct an exploratory analysis of multilevel executive dysfunctions. Guardians completed the Strengths and Difficulties Questionnaire (SDQ) and the Behavior Rating Inventory of Executive Function-Second Edition (BRIEF-2) as part of the assessment process. Children engaged in tasks designed to evaluate both affective and non-affective executive functions. Dimensional exploratory analyses revealed that the ADHD and ASD groups exhibited greater cognitive non-affective executive deficits. However, performance non affective executive functions did not significantly differentiate participants based on their diagnostic status. Ultimately, the only notable shift in executive functioning was observed in the ASD and affective problems group, which demonstrated poorer outcomes.

Copy number variations (CNVs) of the human 16p11.2 locus are associated with several developmental/neurocognitive syndromes. Particularly, deletion and duplication of this genetic interval are found in patients with autism spectrum disorders, intellectual disability and other psychiatric traits. The high gene density associated with the region and the strong phenotypic variability of incomplete penetrance, make the study of the 16p11.2 syndromes extremely complex. To systematically study the effect of 16p11.2 CNVs and identify candidate genes and molecular mechanisms involved in the pathophysiology, mouse models were generated previously and showed learning and memory, and to some extent social deficits. To go further in understanding the social deficits caused by 16p11.2 syndromes, we engineered deletion and duplication of the homologous region to the human 16p11.2 genetic interval in two rat outbred strains, Sprague Dawley (SD) and Long Evans (LE). The 16p11.2 rat models displayed convergent defects in social behaviour and only a few cognitive defects. Interestingly major pathways affecting MAPK3 and CUL3 were found altered in the rat 16p11.2 models with additional changes in males compared to females. Altogether, the consequences of the 16p11.2 genetic region dosage on social behaviour are now found in three different species: humans, mice and rats. In addition, the rat models pointed to sexual dimorphism, with lower severity of phenotypes in rat females compared to male mutants. This phenomenon is also observed in humans. We are convinced that the two rat models will be key to further investigating social behaviour and understanding the brain mechanisms and specific brain regions that are key to controlling social behaviour.

People with autism spectrum disorder (ASD) frequently exhibit challenging behaviors throughout the lifespan, which can have pervasive effects on quality of life. Challenging behaviors have been shown to change over time as a function of various individual-level factors (e.g., cognitive ability), yet research is primarily limited to parent-reported measures. To expand upon this work, the present study aimed to examine trajectories of teacher- and parent-reported challenging behaviors (i.e., hyperactivity, irritability, social withdrawal) and to test whether predictors including ASD features, verbal intelligence quotient, and consistency in reporter impact these trajectories among individuals with ASD or non-spectrum delays from ages 9 to 18. Multilevel models revealed that, according to both teacher and parent report, participants showed the greatest improvement in hyperactivity, less but still notable improvement in irritability, and stable levels of social withdrawal over time. Higher cognitive ability and fewer ASD features emerged as important individual differences related to fewer challenging behaviors. The multi-informant perspective and longitudinal design provide novel insight into the manifestations of these challenging behaviors across different contexts and across time. Findings highlight the importance of addressing challenging behaviors as these behaviors tend to persist throughout development in both home and school contexts, especially for children with particular diagnostic and cognitive profiles. Lay SummaryAccording to both teacher and parent report, youth with autism showed the greatest improvement in hyperactivity, less but still notable improvement in irritability, and stable levels of social withdrawal from school-age to adolescence. Fewer autism features and greater cognitive ability were related to fewer challenging behaviors. This studys use of multiple reporters (e.g., teachers and parents) across time provided insight into the persistence of challenging behaviors in the home and school settings and across development.

Estimating time and making predictions is integral to our experience of the world. Given the importance of timing to most behaviors, disruptions in temporal processing and timed performance are reported in a number of neuropsychiatric disorders such as Schizophrenia, Autism Spectrum Disorder (ASD), Fragile X Syndrome (FXS), and Attention-deficit Hyperactivity Disorder (ADHD). Symptoms that implicitly include disruption in timing are atypical turn-taking during social interactions, unusual verbal intonations, poor reading, speech and language skills, inattention, delays in learning, and difficulties making predictions. Currently, there are no viable treatments for these symptoms, the reason being the underlying neural dysfunction that contributes to timing deficits in neuropsychiatric disorders is unknown. To address this unknown, we have designed a novel Temporal Pattern Discrimination Task (TPSD) for awake-behaving mice. Stimuli consist of audiovisual stimuli that differ in duration. Compared to Wild-Type (WT) mice, Fmr1-/- mice, a well-established mouse model of FXS, showed significant impairment in learning the TPSD task, as evidenced by reduced discriminability indices and atypical licking patterns. Often sensory information is multimodal and indeed studies show that learning in humans and rodents improves with multimodal stimuli than with unimodal stimuli. To test how the multimodal nature of stimuli impacted performance of Fmr1-/- mice, following training on the audiovisual stimuli, we tested mice on audio-only or visual-only stimuli. While WT mice showed significant disruption in performance when tested on unimodal stimuli, Fmr1-/- mice displayed equivalent performance on visual-only stimuli when compared to the multimodal task. Our novel task captures timing difficulties and multisensory integration issues in Fmr1-/- mice and provides an assay to examine the associated neural dysfunction.

BackgroundAutism spectrum disorder (ASD) is defined behaviorally, but measures that probe underlying neural mechanisms may provide clues to biomarker discovery and brain-based patient stratification with clinical utility. Phase-amplitude coupling (PAC) has been posited as a measure of the balance between top-down and bottom-up processing in cortex, as well as a marker for sensory processing and predictive coding difficulties in ASD. We evaluate differences in PAC metrics of resting-state brain dynamics between children with and without ASD and relate PAC measures to age and behavioral assessments. MethodsWe analyzed electroencephalography data collected by the Autism Biomarkers Consortium for Clinical Trials, including 225 (192 male) ASD and 116 (81 male) typically-developing children aged 6-11 years. We evaluated the strength and phase preference of PAC and the test-retest reliability of PAC across sessions. ResultsThere was significantly increased alpha-gamma and theta-gamma PAC strength in ASD. When considering all participants together, we found significant associations of whole brain theta-gamma PAC strength with measures of social communication (Beta = 0.185; p = 0.006) and repetitive behaviors (Beta = 0.166; p = 0.009) as well as age (Beta = 0.233; p < 0.0001); however, these associations did not persist when considering the ASD group alone. There are also group differences in theta-gamma phase preference. ConclusionsThis large, rigorously collected sample indicated altered PAC strength and phase bias in ASD. These findings suggest opportunities for back-translation into animal models as well as clinical potential for stratification of brain-based subgroups in ASD.

Externalizing disorders (EDs) are characterized by outward-directed behaviors such as aggression and hyperactivity. They are influenced by gene-environment interactions, yet our understanding of the genetic predispositions and environmental contexts that give rise to them is incomplete. Additionally, people with EDs often exhibit comorbid internalizing symptoms, which can complicate the clinical presentation and treatment strategies. Following on from our previous studies, we examined genes x environment interaction as a risk factor for EDs by looking at internalizing and externalizing behaviors after social isolation. Specifically, we subjected adgrl3.1 knockout zebrafish -- characterized by hyperactivity and impulsivity -- to a 2-week social isolation protocol. We subsequently assessed the impact on anxiety-like behavior, abnormal repetitive behaviors, working memory, and social interactions. Genotype-specific additive effects emerged, with socially isolated adgrl3.1 knockout fish exhibiting intensified comorbid phenotypes, including increased anxiety, abnormal repetitive behaviors, reduced working memory, and altered shoaling, when compared to WT fish. The findings demonstrate that genetic predispositions interact with environmental stressors, such as social isolation, to exacerbate both externalizing and internalizing symptoms. This underlines the necessity for comprehensive diagnostic and intervention strategies.

Background Diagnosis and treatment monitoring of attention-deficit/hyperactivity disorder (ADHD) largely rely on subjective assessments, highlighting the need for objective markers. Voice features and speech embeddings represent promising candidates for such markers, as they may capture alterations in speech production relevant to ADHD. However, it remains unclear which speech features are most informative for distinguishing ADHD and monitoring treatment effects, and which speech tasks most reliably elicit such differences. Methods Twenty-seven children with ADHD and 27 age-matched neurotypical controls completed six speech tasks across two study visits. Children with ADHD were unmedicated at baseline (first visit) and were assessed under prescribed methylphenidate treatment at follow-up, whereas controls underwent repeated assessment without intervention. Established acoustic voice features (eGeMAPS) and high-dimensional speech embeddings (WavLm, Whisper) were extracted and analysed using linear mixed models to examine baseline group differences and group-by-time interaction effects reflecting medication-associated change patterns. Results At baseline, children with ADHD differed significantly from controls in frequency, spectral, and temporal voice features, characterized by lower and more variable pitch, altered spectral properties, and reduced rhythmic stability. Group-by-time interaction effects indicated medication-associated modulation in the ADHD group, including reduced loudness variability and increased precision of vowel articulation at follow-up, changes not observed in controls. Speech embeddings revealed additional baseline and interaction effects beyond established acoustic features. Free speech tasks, particularly picture description, yielded the most robust and consistent effects. Conclusion Children with ADHD differed from neurotypical controls in vocal features at baseline and showed distinct longitudinal change patterns consistent with medication-related change. These findings support further investigation of speech-based measures as candidate digital phenotypes and potential digital biomarkers in ADHD, with picture description emerging as a particularly promising task for future clinical assessment protocols.

Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by significant and complex genetic etiology. GWAS studies have identified genetic variants associated with ASD, but the functional impacts of these variants remain unknown. Here, we integrated four distinct levels of biological information (GWAS, eQTL, spatial genome organization and protein-protein interactions) to identify potential regulatory impacts of ASD-associated SNPs (p < 5x10-8) on biological pathways within fetal and adult cortical tissues. We found 80 and 58 SNPs that mark regulatory regions (i.e. expression quantitative trait loci or eQTLs) in the fetal and adult cortex, respectively. These eQTLs were also linked to other psychiatric disorders (e.g. schizophrenia, ADHD, bipolar disorder). Functional annotation of ASD-associated eQTLs revealed that they are involved in diverse regulatory processes. In particular, we found significant enrichment of eQTLs within regions repressed by Polycomb proteins in the fetal cortex compared to the adult cortex. Furthermore, we constructed fetal and adult cortex-specific protein-protein interaction networks and identified that ASD-associated regulatory SNPs impact on immune pathways, fatty acid metabolism, ribosome biogenesis, aminoacyl-tRNA biosynthesis and spliceosome in the fetal cortex. By contrast in the adult cortex, they largely affect immune pathways. Overall, our findings highlight potential regulatory mechanisms and pathways important for the etiology of ASD in early brain development and adulthood. This approach, in combination with clinical studies on ASD, will contribute to individualized mechanistic understanding of ASD development.

The current study examined resting-state and event-related neural oscillations associated with ADHD symptoms in children aged 6-12. 77 children were assessed using the Integrated Visual and Auditory Continuous Performance Test (IVA-CPT) and EEG during resting-state. A group of these children also completed a classic visual oddball task. Key findings include increased relative delta activity at left parietal electrodes during eyes-open and decreased relative theta activity at left posterior electrodes during eyes-closed, both associated with poor attention. Increased beta activity at right parieto-occipital electrodes during eyes-open and increased alpha activity at bilateral posterior electrodes during eyes-closed were associated with poor response control. In addition, the power of the P3 component was negatively correlated with attention across most frequency bands and conditions, except for delta power in the standard condition. Furthermore, combining multiple metrics, especially resting-state EEG oscillations, event-related oscillations, and parental ratings, provided a more robust prediction. The current study identified important brain regions and frequency bands related to ADHD symptoms, offering new insights for multi-metric prediction and clinical guidance.