JCPP Advances

Importance: Avoidant/restrictive food intake disorder (ARFID) is a feeding and eating disorder characterized by extremely restricted dietary variety and/or quantity resulting in significant physical health impairment and psychosocial dysfunction. ARFID frequently co-occurs with neurodevelopmental conditions, yet the extent to which this co-occurrence reflects shared genetic or environmental influences remains largely unknown, as few twin or genetic studies of ARFID have been conducted. Objective: To examine the extent to which genetic and environmental influences contribute to the association between a broad ARFID phenotype and neurodevelopmental traits. Design, Setting, and Participants: Population-based twin study using data from the Child and Adolescent Twin Study in Sweden, including 30,374 twins born 1992-2008. Main Outcomes and Measures: A broad ARFID phenotype was identified using a composite measure derived from parent reports and national health registers between ages 6 and 12 years. Parents completed measures of neurodevelopmental traits at age 9 or 12 years, including autism (subdomains: social communication problems and restricted/repetitive behaviors), attention-deficit/hyperactivity disorder (ADHD, subdomains: inattention and impulsivity/hyperactivity), tic disorders, learning disorders, oppositional defiant disorder, conduct disorder, obsessive-compulsive disorder (OCD), sensory perception problems, and sleep problems. Phenotypic associations were estimated using polyserial correlations. Bivariate twin models decomposed variance and covariance into genetic and environmental components. Results: Phenotypic correlations with the broad ARFID phenotype ranged from 0.18 (95% CI: 0.15-0.21) for OCD to 0.36 (95% CI: 0.33-0.38) for autism. Broad genetic correlations (rH; additive plus dominant genetic influences) ranged from 0.27 (95% CI: 0.21-0.33) for conduct disorder to 0.52 (95% CI: 0.44-0.60) for autism-restricted/repetitive behaviors. Genetic factors explained 77% to 95% of all phenotypic correlations. Non-shared environmental correlations were minimal to small, with the largest observed for autism (0.17; 95% CI: 0.08-0.26). Conclusions and Relevance: The broad ARFID phenotype shares substantial genetic influences with a number of neurodevelopmental traits. These findings suggest that the frequent co-occurrence of ARFID with neurodevelopmental traits largely reflects shared genetic influences rather than overlapping environmental influences, supporting the conceptualization of ARFID within a broader neurodevelopmental framework.

Very preterm (VPT) adolescents are at high risk of impaired sustained attention processes, as well as behavioral and socio-emotional problems. Previous studies have highlighted altered attentional patterns of brain activation in this population, but results are inconsistent. The current study aims to explore brain activity related to sustained attention in VPT and full-term adolescents aged 11-18, as well as its associations with attentional capacities and socio-emotional competences. Event-related functional MRI (fMRI) was used to assess sustained attention performance and associated brain activations by comparing VPT (n = 34) and their age-matched full-term (FT, n = 28) peers from a previously validated continuous performance task with gradual onset (gradCPT) paradigm, using two different modality versions (i.e., face and scene). In both groups, linear regression analyses were performed to examine associations between attentional and socio-emotional difficulties and brain activations related to sustained attention. Results show preserved sustained attention processes in VPT adolescents, indicated by comparable behavioral attentional performance and cerebral patterns of activations in both groups across the two modalities of the gradCPT. In addition, VPT adolescents showed over-recruitments in posterior occipital areas compared to FT adolescents. Moreover, higher socio-emotional difficulties (i.e., higher anxiety and social difficulties) in VPT were linked to altered activations specifically in the right middle frontal gyrus, occipito-temporal gyri and bilateral cerebellum, but exclusively observed during the face modality of the gradCPT. Overall, these results suggest that despite preserved sustained attention competences, VPT adolescents present a less mature sustained attention cerebral network, particularly during a task with a social context.

BackgroundThe genetic and environmental aetiology of autistic and Attention Deficit Hyperactivity Disorder (ADHD) traits is known to vary spatially, but does this translate into variation in the association of specific common genetic variants? MethodsWe mapped associations between polygenic scores for autism and ADHD and their respective traits in the Avon Longitudinal Study of Parents and Children (N=4,255 to 6,165) across the area surrounding Bristol, UK, and compared them to maps of environments associated with the prevalence of autism and ADHD. ResultsOur maps suggest genetic associations vary spatially, with consistent patterns for autistic traits across polygenic scores constructed at different p-value thresholds. Patterns for ADHD traits were more variable across thresholds. We found that the spatial distributions often correlated with known environmental influences. ConclusionsThese findings shed light on the factors that contribute to the complex interplay between the environment and genetic influences in autism and ADHD traits. Key pointsO_LIThe prevalence of autism and ADHD vary spatially. C_LIO_LIOur study highlights that genetic influences based on PGS also vary spatially. C_LIO_LIThis spatial variation correlates with spatial variation in environmental characteristics as well, which would be interesting to examine further. C_LIO_LIOur findings have implications for future research in this area examining the factors that contribute to the complex interplay between the environment and genetic influences on autistic and ADHD traits. C_LI

Neither the neurological underpinnings of autism spectrum disorder (ASD) nor their contribution to sex differences are well understood. In previous cross-sectional studies of axonal conduction velocity, the speed of action potential transmission, was observed to be decreased in autistic individuals, and this deficiency was associated with cognitive and behavioral differences. This longitudinal study aims to better understand how changes in neuronal microstructure contribute to the developmental trajectory of individuals with ASD and specifically to sex-differences in behavior during the adolescent period. Eighty-two participants (34 ASD, 41 female) completed multi-year longitudinal behavioral and neuroimaging testing. Pubertal development significantly mediated and accelerated age-related increases in conduction velocity, with girls with autism exhibiting greater increases in cortex over time and boys exhibiting greater increases in white matter (WM). Girls with autism exhibited more rapid increases in frontal and parietal cortices while boys showed relatively higher increases in insular cortex compared to girls. Across all boys, conduction velocity increased in WM at a higher rate than girls, but increased more slowly in autistic relative to non-autistic boys. Parent-reported anxious and depressive symptomatology also increased over time in girls with autism, whereas behavioral metrics associated with ASD declined, especially in boys. Notably, conduction velocity showed significant associations with parent-reported anxious and depressive symptomatology in many of the same brain regions that showed sex-specific developmental changes. These results indicate that neurodevelopmental changes in conduction velocity may underlie sex-linked biological mechanisms and contribute to differences in behavioral expression in autistic and non-autistic development.

BackgroundComorbidity and heterogeneity in psychiatric disorders may stem from a general psychopathology (p) factor influenced by both genetic and environmental factors. Although the relative contributions of these influences on psychopathology are established, the longitudinal associations between p-factor and specific environmental exposures across development are not well understood. Using a longitudinal genetically informative design, this study investigates the association between the home environment and p-factor across childhood. MethodsData were obtained from the Twins Early Development Study (TEDS). Cross-lagged panel analyses were conducted separately to ascertain the direction of associations between parent-rated p, self-rated p, and self-rated home environment (chaos at home and parental discipline) at ages 9, 12, and 16 (N=6,213). Biometric autoregressive cross-lagged twin models were used to assess the aetiology of these associations, and MZ differences analyses were used to control for familial effects. ResultsBoth latent factors were stable over time, although twin-rated p-factor (r = 0.44-0.40) was more variable than parent-rated p-factor (r = 0.72-0.63). Home environment was more variable than p-factor uniformly. Small, significant bi-directional associations were found between p-factor and home environment, with stronger cross-lagged paths from p-factor to home environment than vice versa. These longitudinal associations persisted over time, though attenuated for parent-rated p-factor. Genetic analyses revealed that bi-directional cross-lagged paths were largely explained by shared environmental factors, with a smaller proportion explained by genetic factors. This pattern of results was confirmed in MZ differences analyses. ConclusionsOur findings suggest a dynamic and bidirectional relationship between p-factor and the home environment across development, predominantly influenced by shared environmental factors. Changes in one can influence the other, highlighting the complexity of psychopathologys environmental influences. This underscores the need for further investigation into gene-environment interplay to inform approaches to psychopathology prevention and intervention. Key points and relevanceO_LIThe relationship between p-factor and the home environment is dynamic and bidirectional, indicating that changes in one can influence the other across different developmental stages. However, the effect sizes of these relationships were modest. C_LIO_LIShared environmental factors played a major role in driving cross-lagged associations between p-factor and the home environment, with some genetic contribution, suggesting that the family environment can significantly shape this relationship. C_LIO_LIThese findings necessitate deeper investigations into gene-environment interplay in shaping psychopathology. A better understanding of these dynamics could inform effective prevention and intervention strategies for developmental psychopathology. C_LI

AimAutistic children have a high but varied prevalence of internalizing and externalizing problems. This study aimed to identify the subtypes of internalizing and externalizing problems among autistic preschool children in Japan, examine their temporal stability, and investigate differences in participation in daily life and family outcomes across these subtypes. MethodsA prospective cohort study was conducted with 275 caregivers of autistic children aged 51-75 months. Internalizing and externalizing problems were assessed using the Strengths and Difficulties Questionnaire. ResultsLatent transition analysis identified five subtypes: Low-symptom, High-emotional, Externalizing, Comorbid, and Peer-difficulty groups. Membership in the High-emotional and Externalizing groups was relatively stable over time, whereas the Peer-difficulty group showed frequent transitions to subtypes with higher levels of internalizing or externalizing problems. Significant differences in participation in daily life and family outcomes were observed across subtypes, but these patterns were inconsistent with a simple gradient of symptom levels. ConclusionsThe novel findings that the temporal stability of subtype membership varied and that differences in participation in daily life and family outcomes were observed across the subtypes suggest that the heterogeneity of internalizing and externalizing problems may be associated with variations in childrens participation in daily life and family outcomes over time. Plain Language SummaryAutistic preschool children often experience emotional and behavioral difficulties, but the way these difficulties manifest varies widely across individuals. This study aimed to identify the patterns of these difficulties, examine how they change over time, and investigate how participation in daily life and family outcomes differ across autistic preschool children. We conducted a study with 275 caregivers of autistic children aged 4-6 years in Japan. From caregiver reports of childrens emotional and behavioral difficulties, five distinct patterns were identified: a group with mainly emotional difficulties, a group with mainly behavioral difficulties, a group with both types of difficulties, a group with relatively low levels of difficulties, and a group characterized primarily by peer-related difficulties. Our findings suggest that different patterns of emotional and behavioral difficulties are associated with differences in childrens participation in daily life and family outcomes. These differences could not be explained simply by the overall severity of difficulties but rather reflect distinct patterns based on the type of difficulty. The results indicate that autistic children face diverse difficulties that change over time.

Abstract Parental depression and early child neurodevelopment are closely interconnected, yet few population-based studies have examined both maternal and paternal depression in relation to early neurodevelopmental risk. This study aimed to examine the association between child neurodevelopmental risk and parental depression in the French national birth cohort Etude Longitudinale Francaise depuis l'Enfance (ELFE). We conducted a cross-sectional analysis of 12,953 children and their parents who participated in the 2-year follow-up. Child neurodevelopmental risk was assessed at age 2 years using the Modified Checklist for Autism in Toddlers and categorized as low, intermediate, or high risk. Parental depression was assessed using the Kessler Psychological Distress Scale and defined as maternal depression, paternal depression, or depression in at least one parent. Multivariable logistic regression models were adjusted for sociodemographic, pregnancy-related, and child characteristics. Compared with low child neurodevelopmental risk, intermediate risk was associated with higher odds of maternal depression and depression in at least one parent. High child neurodevelopmental risk was associated with substantially higher odds of maternal depression and depression in at least one parent. Associations with paternal depression were weaker and were no longer statistically significant after adjustment. These findings suggest that parental depression, particularly maternal depression, is associated with early child neurodevelopmental risk from the stage of initial developmental concerns. They support an integrated, family-centred approach combining early identification of child developmental vulnerability with attention to parental mental health.

The most highly predictive polygenic scores in the behavioural sciences are for cognitive traits, especially general cognitive ability (g) and educational attainment. We combined polygenic scores derived from genome-wide association studies of adult g and educational attainment to create adult 'polygenic g scores' which we used to chart the course of cognitive development of 10,000 white British children from toddlerhood through early adulthood. We integrated cross-sectional regression, latent growth curve, and confirmatory factor analysis to systematically characterise cognitive development. Polygenic g score showed minimal prediction in toddlerhood, modest prediction in childhood, and substantial prediction by early adulthood accounting for 12% of the variance. Higher polygenic g scores were associated with faster cognitive growth in latent growth models. Prediction was strongest for a cross-time latent cognitive factor (15%) capturing cognitive ability across development. By integrating polygenic prediction directly into a structural equation model framework, we provided a theoretical upper bound of genetic influences on g under minimal measurement error. We also examined the polygenic g score's prediction of educational achievement, behaviour problems, and anthropometric outcomes and found similar developmental increases in prediction for educational achievement. Together, our findings demonstrate that adult polygenic g scores can be a useful tool for charting the development of cognitive traits.

BackgroundParental genetics matters for childrens behavioural difficulties, but the extent to which this is due to direct genetic transmission versus environmentally mediated indirect genetic effects remains unclear. MethodsWe studied eight European birth cohorts with over 33,000 family-based trio samples. We analysed polygenic scores (PGSs) for 13 mental health and neurodevelopmental conditions and their composite indices (PC1 and mean) representing general neuropsychiatric liabilities, as well as educational attainment (EA) and alcohol and cigarette use, from children (PGSc), mothers (PGSm), and fathers. Child internalising, externalising, and total difficulties reported by mothers and/or fathers were examined at preschool and school ages. We then conducted multivariate meta-analyses to combine cohort-level results. FindingsWe observed several direct genetic effects on externalising difficulties, while indirect genetic influences were mainly identified for internalising difficulties. Specifically, child PGSs for attention-deficit/hyperactivity disorder (ADHD) and EA predicted higher and lower levels, respectively, of child externalising and total difficulties (all pFDR<0{middle dot}001; for school-aged externalising difficulties, PGSc-ADHD: {beta}=0{middle dot}121 [95% CI 0{middle dot}091 to 0{middle dot}151], pFDR<0{middle dot}0001; PGSc-EA: {beta}=-0{middle dot}095 [95% CI -0{middle dot}127 to -0{middle dot}063], pFDR<0{middle dot}0001), whereas maternal PGSs for major depressive disorder (MDD) and general neuropsychiatric liabilities were associated with internalising and total difficulties across parental raters and child ages (all pFDR<0{middle dot}05; for school-aged internalising difficulties, PGSm-MDD: {beta}=0{middle dot}049 [95% CI 0{middle dot}017 to 0{middle dot}081], pFDR=0{middle dot}016; PGSm-PC1: {beta}=0{middle dot}056 [95% CI 0{middle dot}022 to 0{middle dot}091], pFDR=0{middle dot}011). No statistically significant effects from paternal PGSs were identified. InterpretationIn this multi-cohort study, findings across multiple traits, raters, and ages supported several direct genetic effects of ADHD and EA on child externalising difficulties and indirect genetic effects on internalising difficulties, especially maternal depression and general neuropsychiatric liabilities. These suggest that child internalising difficulties are not solely driven by direct genetic transmission. More comprehensive research is needed to better understand the mechanisms involved, and ultimately how to ameliorate child behavioural difficulties. FundingEU, ERC, RCN, RCF, UKRI, SERI, DFG Research in contextO_ST_ABSEvidence before this studyC_ST_ABSIndirect genetic effects (IGEs) refer to the influence of parental genotypes on offspring outcomes beyond direct genetic effects (DGEs), for example via environmental pathways. While IGEs on offspring cognitive traits are well-established for educational attainment, evidence for IGEs of parental liabilities to mental health and neurodevelopmental conditions remains limited. To assess the current state of evidence, we conducted a systematic search of published studies applying trio-based polygenic score (PGS) designs to child and adolescent mental health outcomes. We identified 141 primary studies in MEDLINE, Embase, PsycInfo, and Web of Science, by 6 March 2025, after removing duplicates; following screening, 12 studies met inclusion criteria (see supplement for a full description including results). Ten out of the 12 studies focused on externalising outcomes, with little or inconsistent support for IGEs. When observed, IGEs were mainly driven by maternal liabilities to autism, educational attainment, and cognitive performance on child outcomes. The current evidence was too limited and heterogeneous to synthesize findings quantitatively, therefore a qualitative synthesis was conducted. Many studies were statistically underpowered, and the observed IGEs were in all cases sample-specific. There were no published multi-cohort studies. Added value of this studyWe integrated information across over 33,000 mother-father-child trios from eight European cohorts, investigating 18 PGSs from parents and children, using maternal and paternal ratings of offsprings internalising, externalising, and total difficulties as outcomes at both preschool and school age. We mainly observed DGEs on externalising difficulties, consistent with previous studies. Some evidence of IGEs was found for internalising and total difficulties. IGEs were often found to be maternally driven, with the most robust evidence across ages and raters emerging for maternal depression and general neuropsychiatric liabilities. Implications of all the available evidenceThe current evidence suggests that childrens behavioural difficulties, especially internalising difficulties, may be partly driven by the environment shaped by maternal neuropsychiatric liabilities. Ours and previous findings highlight a pressing need for more comprehensive studies across different cohorts, raters, outcomes, and time points to understand the true extent of IGEs in the intergenerational transmission of mental health.

Autism spectrum disorder is a heterogeneous neurodevelopmental disorder. Early brain overgrowth yet reduced cerebellar size is well recognized for autism, but cortical regions involved show inconsistent patterns of alteration. No complete and replicable map of early regional brain size alterations has been charted. It is also not clear whether individual differences in brain size relate to autism symptom severity and cognitive deficits and predict later language outcomes. We leveraged structural MRI data from 166 autistic and 109 typical developing toddlers to comprehensively and systematically investigate regional gray matter volume alterations and cortical surface area and thickness perturbations in autism compared to typical developing toddlers using linear mixed-effect models. We then examined their replicability in an independent cohort of 38 autistic and 37 typical developing toddlers. We further investigated associations between regional brain size and symptom severity, Mullen and Vineland cognitive performance using linear regression models. Lastly, we investigated whether early brain size (at intake mean age of 2.5 years) can improve support vector machine prediction of language outcome at 3-4 years of age when added to a model containing intake clinical and behavioral measures. Compared to typical developing toddlers, autistic toddlers presented larger or thicker lateral temporal regions, smaller or thinner frontal lobe and midline structures, larger callosal subregion volume, and smaller cerebellum. Most of these differences were replicated in an independent toddler cohort. Moreover, the identified gray matter alterations were related to autism symptom severity and cognitive impairments at intake, and, remarkably, they improved the accuracy for predicting later language outcome beyond intake clinical and demographic variables. Gray matter volume, thickness, and surface area in regions involved in language, social, and face processing were altered in autistic toddlers. Alterations in these regions are major early-age developmental attributes of autism. The early-age alterations in these cortical attributes in different regions may be the result of dysregulation in multiple neural processes and stages, consistent with prenatal multi-process, multi-stage models of autism. Here we also show these gray matter alterations are promising prognostic biomarkers for language outcome prediction.

BackgroundHigh cognitive ability is an almost universally positive prognostic indicator in the context of neurodevelopmental, neuropsychiatric, and neurodegenerative conditions. However, "twice-exceptional" individuals, those who demonstrate exceptionally high cognitive ability (gifted) and exhibit profound behavioral and mental health challenges, are a striking exception to this rule. MethodsWe digitized the clinical records of N=1,074 clients from a US-based specialty clinic serving gifted students. This included a broad array of diagnostic, cognitive, achievement, and behavioral data, including self, teacher, and parent reported items. We conducted both hypothesis-driven and unsupervised learning analyses to 1) identify characteristics whose association with full-scale IQ (FSIQ) was dependent on autism diagnosis and 2) identify cognitive archetypes associated with autism diagnosis and related behaviors. We tested the generalization of our findings using data from the SPARK (N=17,634) and ABCD studies (N=10,602). ResultsAutistic individuals with IQ >= 120 were nearly 15 times more likely to enter adulthood undiagnosed compared to lower-IQ (IQ < 70) counterparts. Self-reported sense of inadequacy was most strongly associated with increasing FSIQ specifically among autistic clients (beta=0.3, 95% CI:[0.15,0.45], p=7.1x10-5). Similarly, self, parent, and teacher reports of anxiety increased with FSIQ (all p<0.05) in autistic individuals, in striking opposition to the ameliorating effect of FSIQ seen in non-autistic individuals. We uncovered a pattern of decreased processing speed (PS) coupled with very high verbal comprehension (VC), a PS/VC discrepancy, that was associated with autism, inattention, and internalizing problems. Similar cognitive-behavioral links were also observed in the ABCD study. Finally, we found a significant association between the PS/VC discrepancy and polygenic risk for autism in the ABCD sample (t=2.9, p=0.004). ConclusionsOur results suggest that autistic individuals with exceptional ability are underserved and suffer disproportionately from high anxiety and low self-worth. In addition, elevated IQ with a significant PS/VC discrepancy appears to be a clinically and genetically meaningful biotype linked to autism.

BackgroundMost preschool autistic children exhibit substantial language delays, yet only [~]25% remain minimally verbal (MV) throughout life. Previous studies have demonstrated that development of expressive language abilities is crucial for improving long-term outcomes. This study aimed to identify early predictors of later expressive language development specifically in MV preschool autistic children. MethodsWe analyzed prospective data collected from 99 MV autistic children, who were 27.7 months old at diagnosis, on average. All children completed an ADOS-2 assessment at diagnosis and again 12-24 months later. We classified children into three expressive language groups at follow up: MV, one-word phase, and phrases phase. Logistic regression analyses were used to identify significant predictors of expressive language abilities at follow up. Predictors included ADOS-2 social affect (SA) calibrated severity scores (CSS), ADOS-2 restricted and repetitive behavior (RRB) CSS, cognitive scores, and joint attention (JA) scores, derived from a summation of six ADOS-2 items. ResultsChildren who successfully developed expressive language abilities at follow-up (i.e., were in the one-word or phrases groups) had significantly lower ADOS-2 SA CSS and JA scores at diagnosis. Logistic regression analyses demonstrated that both ADOS-2 SA CSS and JA scores at diagnosis predicted expressive language outcomes while cognitive scores and ADOS-2 RRB CSS did not. Moreover, concurrent improvements in JA were significantly larger in children who developed expressive language. ConclusionsPreschool MV autistic children with better social abilities, and specifically JA abilities, at diagnosis were more likely to develop expressive language within 1-2 years. JA scores derived from the ADOS-2 offer an easily accessible and widely available measure with important prognostic value for these children.

BackgroundTemperament traits, which reflect early emerging individual differences in reactivity and regulation, are well-established correlates of psychopathology. However, studies have historically examined static temperament-psychopathology associations within limited age ranges. Research is required to understand the developmental dynamics of these associations. MethodsWe leveraged data from a longitudinal cohort (N = 767) with repeated measures in infancy and at ages 2 years, 3 years, 5 years, 7 years, and 11 years to examine predictive and concurrent associations between temperament traits (negative affectivity, surgency, effortful control, behavioral inhibition) and psychopathology (internalizing, externalizing) symptoms. We estimated time-varying associations using generalized additive mixed models to quantify variation in the significance and magnitude of associations from infancy through early adolescence. ResultsGreater negative affectivity consistently predicted higher internalizing and externalizing symptoms from infancy through 11 years. Surgency showed differential patterns, with higher surgency associated with lower internalizing symptoms but greater externalizing symptoms. Surgency from 2 years was associated with both internalizing and externalizing symptoms over proximal developmental intervals, whereas at 3 years, associations with externalizing extended distally through 11 years, while associations with internalizing remained proximal. Higher effortful control was associated with fewer internalizing and externalizing symptoms, with stronger effects for externalizing symptoms. Behavioral inhibition at 3 years was associated with internalizing symptoms ages 3 and 5 years. The significance and magnitude of associations between temperament domains and psychopathology symptoms varied based on developmental timing. ConclusionsTemperament traits show differential associations with psychopathology symptoms, depending on the specific temperament trait and psychopathology domain. Further, the significance and magnitude of associations vary based on developmental timing. These findings highlight the importance of considering differential traits, domains, and developmental timing when considering the potential role of temperament in psychopathology.

BackgroundThe expression of autism traits sufficient to meet criteria for a diagnosis can occur early (by 3 years) or later (from mid-childhood onwards). It remains unknown whether variation in age of onset is due to clinical recognition or whether it reflects distinct biological pathways. One way of addressing this question is by investigating biological differences very early in development associated with age of onset. We use a prospective design to look at event related potentials to faces, one of the most robust biomarkers in autism. MethodsA sample of 102 infants (aged 6-10 months, 54% female) with an older autistic sibling had EEG recorded whilst viewing faces (faces versus noise; gaze towards versus away). Autism diagnostic assessments were conducted at three years and again in mid-childhood (aged 6-12 years), resulting in early diagnosed (at age 3; N=22), later diagnosed (at mid-childhood; N=21) and no autism (N=59) groups. ResultsWhile a short latency response (P1) does not associate with autism outcome, a mid-latency component (N290) associates with early onset autism only, and a later latency component (P400) associates with both early and later onset autism. ConclusionTemporal stages of face processing in infancy differentially associate with age of autism onset such that an earlier age of diagnosis is associated with earlier stage deviation within the event-related waveform. Early and later onset autism may represent different biological subtypes, with different early brain development, challenging the view of one etiological pathway and that variation in diagnostic age is solely due to clinical ascertainment.

Williams Syndrome (WS) is a rare neurodevelopmental disorder associated with intellectual disability and increased vulnerability to traits such as anxiety, perseveration, and belief inflexibility. In the general population, these traits are linked to self-reported thought disturbances such as paranoia and delusions. However, little is known about how such disturbances present in WS, largely due to concerns regarding the validity of self-report in this population. To address this gap, we collected self- and caregiver-reported measures characterizing thought disturbances and related cognitive traits in adults with WS, assessing inter-rater reliability and correlations among measures. Total scores were similar across reporters, except for delusional ideation, which participants endorsed more strongly than caregivers. Several participants also reported clinically significant levels of paranoia, delusions, and worry that were not captured by caregiver report. These findings suggest that self-report is a valid method for accurately characterizing the severity and nature of thought disturbances in WS.

BackgroundChildren diagnosed with ADHD and other comorbid mental health conditions often exhibit more severe functional impairments than those without comorbid conditions, including a tendency for their ADHD symptoms to persist into later developmental stages. We conducted a systematic review and quantitative analysis to investigate the extent to which specific childhood comorbidities (internalizing, externalizing and neurodevelopmental conditions) predict the persistence of childhood ADHD into later developmental stages. MethodsWe extracted data from 26 studies meeting the criteria for inclusion and applied multilevel random effects models to obtain pooled estimates of Cohens d for selected predictors on ADHD persistence. ResultsChildhood comorbid internalizing and externalizing conditions (d=0.19 and d=0.31, respectively), but not neurodevelopmental disorders, were significantly associated with ADHD persistence. After adjusting for covariates (sex, age and other comorbidities), this association diminished for externalizing conditions (dadj=0.24) and was no longer significant for internalizing conditions (dadj=0.05). The association between comorbid externalizing behavior problems and ADHD persistence was found only in studies that used parent-reported data to measure childhood ADHD and externalizing conditions, but not in studies that included teacher-reported childhood symptoms. ConclusionsChildhood comorbid externalizing and, to a lesser extent, internalizing conditions were associated with the persistence of ADHD, but this association may be partially due to confounders. Childhood comorbidity of neurodevelopmental disorders does not appear to increase the likelihood of ADHD persistence.

BackgroundDepression is highly prevalent in autistic individuals, yet its underlying psychological mechanisms remain insufficiently understood, especially in populations who self-identify as autistic but lack a formal diagnosis. MethodsUsing a moderated mediation approach (structural equation modeling), we investigated how autistic traits relate to depressive symptoms in three groups: individuals with clinically diagnosed autism (ASD, N = 136), self-identified autistic individuals without formal diagnosis (ASD-sd, N = 100), and neurotypical controls (N = 1566). Five psychosocial mediators were tested: mentalizing, anxious and avoidant attachment, perceived social support, and psychological flexibility. ResultsDepressive symptoms were significantly higher in both autistic groups compared to neurotypical controls. The association between autistic traits and depressive symptoms was fully mediated by a combination of psychological flexibility, attachment style, mentalizing, and perceived social support. Among these, psychological flexibility emerged as the strongest and most consistent mediator across all groups. In contrast, mentalizing showed an indirect effect only in the non-ASD group, while avoidant attachment was a significant mediator solely in the clinically diagnosed ASD group. Perceived social support showed a modest indirect effect only in the non-ASD group. ConclusionsOur findings support a transdiagnostic model in which psychological flexibility plays a central protective role against depression across varying levels of autistic traits. Meanwhile, attachment-related and social-cognitive vulnerabilities contribute in different ways depending on diagnostic status. These results underscore the clinical importance of individualized interventions targeting such modifiable factors. Mentalization-based treatment, adapted for neurodiverse populations, may offer a promising framework for addressing both common and subgroup-specific mechanisms. Lay abstractMany autistic people experience depression, but we still know little about why this happens and what psychological factors are involved, especially for those who see themselves as autistic but dont have a formal diagnosis. We studied three groups: people with diagnosed autism, people who self-identify as autistic, and people without autism. We wanted to understand which psychological traits might explain why autistic traits are linked to depression. We found that a skill called psychological flexibility (being able to stay present and adapt to difficult emotions) was the most important protective factor in all groups. Other factors, like how people think about relationships (attachment) and how well they understand themselves and others (mentalizing), were only important for some groups. These findings suggest that therapies which improve flexibility and help with emotional connection may reduce depression in autistic people and those with high autistic traits.

BackgroundA range of rare chromosomal micro-deletions or -duplications (Copy Number Variants - CNVs) are associated with high risk of neurodevelopmental and mental health conditions (ND-CNVs). There is great individual variability in outcomes, but we lack insights into the contributing social factors, including family functioning. MethodsCaregivers of 598 children and young people (CYP) with a range of 16 ND-CNVs and 222 siblings without ND-CNVs (controls) completed questionnaires on overall family climate (cohesion and conflict) as well as caregiver-CYP relationship warmth and hostility and took part in a research diagnostic interview about CYPs psychiatric symptoms. CYPs intelligence quotient (IQ) was also measured. ResultsComparisons with published data from neurotypical families indicated that families affected by ND-CNVs are characterised by higher family cohesion and conflict as well as lower caregiver-CYP warmth and hostility. Symptoms of oppositional defiant disorder reduced more steeply in CYP with ND-CNVs compared to controls with increasing family cohesion (interaction effect: {beta} = -0.14, p = 4.65 x 10-{superscript 2}). In contrast, they rose more steeply with increasing family conflict (interaction effect: {beta} = 0.18, p = 1.05 x 10-{superscript 2}). Furthermore, symptoms of mood disorder increased more steeply with increased caregiver-CYP hostility in CYP with ND-CNVs (interaction effect: {beta} = 0.15, p = 4.55 x 10-{superscript 2}). ConclusionsRaising a CYP with a rare genetic condition is challenging. Timely access to interventions that support caregivers in fostering a positive family environment may reduce behavioural difficulties in CYP, with subsequent benefits for family functioning.

Abstract Background Gene dosage disorders impact cognition and psychopathology, but outcomes vary widely amongst carriers of the same variant. Recent work has sought to better predict proband outcomes using measures of corresponding traits in family members. However, family-based models have not yet been prospectively quantified across several traits in different genetic disorders, nor evaluated for the precision they afford: both crucial issues for clinical implementation. Methods In a first test case for these questions, we apply regression analyses to quantify and compare family-based prediction of 12 traits (including IQ, autism- and ADHD-related traits) in 433 individuals from families including a proband with XXY or XYY syndrome (N=93 and 58, respectively). Results The 12 traits vary substantially in their proband-family associations (0.001<|r|<0.55) - with differences emerging between XXY and XYY syndrome. Only two traits also show significant and similar proband-family associations in both aneuploidies, with the greatest concordance found for IQ. A family-based model for IQ prediction in male sex chromosome trisomies significantly reduces error vs. a group mean IQ model (F = 7.4, p = 0.006), but only in 65% of probands, and with mean error reduction of ~2 IQ points. Conclusions Family-based prediction of neuropsychiatric traits in genetic syndromes likely requires trait- and syndrome- specific models. Family models can significantly improve outcome prediction for IQ, but to variable degrees across individuals and with a small mean improvement. By mapping and quantifying these limits, our work helps draft a roadmap for refinement of family-based prediction of proband outcomes in gene dosage disorders.

ObjectivePica has been largely understudied in general population samples. Pica occurs most often in childhood and appears more prevalent in individuals with autism and developmental delays (DD). Pica occurrence in the general population is poorly understood due to few epidemiological studies. MethodData on 10,109 caregivers from the Avon Longitudinal Study of Parents and Children (ALSPAC) study who reported pica behavior at 36, 54, 66, 77, and 115 months on their child were included. Autism was obtained through clinical and education records, while DD was derived from the Denver Developmental Screening Test. ResultsA total of 312 parents reported pica behaviors in their child. Of these, 19.55% reported pica at least at two waves (n=61). Pica was most common at 36 months (N=226; 2.29%) and decreased as children aged. A significant association was found between pica and autism at all five waves (p < .001). There was a significant relationship between pica and DD, with individuals with DD more likely to experience pica than those without DD at 36 (p = .01), and 54 (p < .001), 65 (p=.04), 77 (p <.001), and 115 months (p=.006). Exploratory analyses examined pica behaviors with broader eating difficulties and child body mass index. DiscussionPica is an uncommon behavior in childhood; however, children with DD or autism may benefit from pica screening and diagnosis between ages 36-115 months. Children who exhibit undereating, overeating, and food fussiness may also engage in pica behaviors.