A convergent structure-function substrate of cognitive imbalances in autism.

BACKGROUND: Autism spectrum disorder (ASD) is a common neurodevelopmental diagnosis showing substantial phenotypic heterogeneity. A leading example can be found in verbal and nonverbal cognitive skills, which vary from elevated to impaired compared with neurotypical individuals. Moreover, deficits in verbal profiles often coexist with normal or superior performance in the nonverbal domain. METHODS: To study brain substrates underlying cognitive imbalance in ASD, we capitalized categorical and dimensional IQ profiling as well as multimodal neuroimaging. RESULTS: IQ analyses revealed a marked verbal to nonverbal IQ imbalance in ASD across 2 datasets (Dataset-1: 155 ASD, 151 controls; Dataset-2: 270 ASD, 490 controls). Neuroimaging analysis in Dataset-1 revealed a structure-function substrate of cognitive imbalance, characterized by atypical cortical thickening and altered functional integration of language networks alongside sensory and higher cognitive areas. CONCLUSION: Although verbal and nonverbal intelligence have been considered as specifiers unrelated to autism diagnosis, our results indicate that intelligence disparities are accentuated in ASD and reflected by a consistent structure-function substrate affecting multiple brain networks. Our findings motivate the incorporation of cognitive imbalances in future autism research, which may help to parse the phenotypic heterogeneity and inform intervention-oriented subtyping in ASD.

Debate: How far can we modify the expression of autism by modifying the environment?

Following Green (Child and Adolescent Mental Health, 2023, 28, 438) the emergence of a manifest autistic phenotype, during preschool years, represents a discontinuity from preclinical or subclinical states. We propose that this discontinuity suggests that autistic children experience superior interest for, and processing of non-social information, whereas children without autism favor social information processing. This is produced by perceptual over-functioning, still allowing self-taught non-social language learning in a substantial fraction of prototypical autistic children. A new set of rigorous intervention studies using Pediatric Autism Communication Therapy (PACT), based on the synchrony principle, brought autistic children below the ADOS diagnostic threshold (Whitehouse et al., JAMA Pediatrics, 2021, 175, e213298). We now know that adaptation of the child's social environment can produce changes in the manifestations of autism in the pre-school period and later. However, the limitation of these changes, combine with evidence of non-social learning of language suggests that clinicians should combine lateral tutorship (the parallel, unsynchronous exposure of information) with the synchrony (early dyadic communication and engagement) principle to create a new generation of strength-based interventions.

A longitudinal study on language acquisition in monozygotic twins concordant for autism and hyperlexia.

BACKGROUND: Hyperlexia, a strong orientation towards written materials, along with a discrepancy between the precocious acquisition of decoding skills and weaker comprehension abilities, characterizes up to 20% of autistic children. Sometimes perceived as an obstacle to oral language acquisition, hyperlexia may alternatively be the first step in a non-social pathway of language acquisition in autism. METHOD: We describe two monozygotic twin brothers, both autistic and hyperlexic, from the ages of 4 to 8 years old. Following an in-depth diagnostic assessment, we investigated cross-sectionally and longitudinally their verbal and non-verbal cognitive abilities, language, reading and writing skills, interests, and strengths. RESULTS: The twins' features, including their high non-verbal level of intelligence, their special interests, and their skills in various domains, were highly similar. Their language consisted exclusively of letters and numbers until their fourth year. After that, their vocabulary broadened until they developed full sentences, and their perception-related interests expanded and merged over time to serve the development of other skills. CONCLUSION: Our results show that hyperlexic skills can be harnessed to favor oral language development. Given the strong concordance between the twins' cognitive and behavioral phenotypes, we discuss the environmental and genetic influence that could explain their abilities.

Psychometric validation of the French version of the PedsQLTM4.0 generic health-related quality of life questionnaire for 2-4-year-old children.

The Pediatric Quality of Life Inventory version 4.0 (PedsQLTM4.0) is an internationally recognized, generic, health-related quality of life (HRQoL) questionnaire, but its proxy 2-4-year-old version has not been validated in France. This study proposes a psychometric validation of this tool for French children aged 2 to 4 years and 11 months. A total of 220 parents of typically developing children participated. Acceptability was explored. Internal consistency was tested using Cronbach's alpha. Factor structure was tested using an exploratory structural equation modeling (ESEM). Risk of bias was assessed regarding gender and age effect on HRQoL using Student's t test. Except for school functioning, compliance was good (< 2.9%). No floor effects were observed, but ceiling effects were found for all scores. The total score had good internal consistency (Cronbach's α = .82). The Cronbach's α of each subscale was between .53 and .71. Factor analysis rejected the original 4-factor structure and revealed an alternative 2-factor structure. The total score and emotional scale score did not appear to be sensitive to gender or child age.  Conclusions: The PedsQLTM4.0 generic HRQoL questionnaire presents good psychometric properties, regarding acceptability and reliability. For use among French children aged 2 to 4 years and 11 months, we recommend retaining the total score and the emotional scale score.

Clinical Situations in Which the Diagnosis of Autism is Debatable: An Analysis and Recommendations.

The "autism spectrum disorder" (ASD) construct and its current diagnostic criteria have led to the inclusion of increasingly heterogeneous and decreasingly atypical individuals under its definition. This broad category, based on the polymorphic clinical expression of common genetic variants underpinning the risk of autism, is likely beneficial for certain individuals. However, determining the boundaries between ASD and typical individuals, as well as those with other neurodevelopmental conditions, remains an issue of which the importance is growing with the increase in ASD prevalence. We identified four clinical contexts associated with a questionable, poorly justified, or unhelpful ASD diagnosis: (1) those in which diagnostic instruments raise uncertainties, (2) in the context of a subclinical presentation, (3) when early autistic signs tend to fade away during development, and (4) when comorbidities are prominent. We argue that in certain cases, a diagnosis of ASD may not be the most suitable, timely, or helpful medical act and provide recommendations for clinical practice when facing such situations.

Autism spectrum heterogeneity: fact or artifact?

The current diagnostic practices are linked to a 20-fold increase in the reported prevalence of ASD over the last 30 years. Fragmenting the autism phenotype into dimensional "autistic traits" results in the alleged recognition of autism-like symptoms in any psychiatric or neurodevelopemental condition and in individuals decreasingly distant from the typical population, and prematurely dismisses the relevance of a diagnostic threshold. Non-specific socio-communicative and repetitive DSM 5 criteria, combined with four quantitative specifiers as well as all their possible combinations, render limitless variety of presentations consistent with the categorical diagnosis of ASD. We propose several remedies to this problem: maintain a line of research on prototypical autism; limit the heterogeneity compatible with a categorical diagnosis to situations with a phenotypic overlap and a validated etiological link with prototypical autism; reintroduce the qualitative properties of autism presentations and of current dimensional specifiers, language, intelligence, comorbidity, and severity in the criteria used to diagnose autism in replacement of quantitative "social" and "repetitive" criteria; use these qualitative features combined with the clinical intuition of experts and machine-learning algorithms to differentiate coherent subgroups in today's autism spectrum; study these subgroups separately, and then compare them; and question the autistic nature of "autistic traits".

Autism comorbidities show elevated female-to-male odds ratios and are associated with the age of first autism diagnosis.

OBJECTIVE: To investigate the association between the comorbidity rates in autism and sex, birth year and the age at which autism was first diagnosed and compare the relative impact of each. METHOD: Using the Danish National Patient Registry, cumulative incidences up to the age of 16 for 11 comorbid conditions (psychosis, affective disorders, anxiety disorders, conduct disorder, eating disorders, obsessive-compulsive disorder, attention-deficit hyperactivity disorder, epilepsy, tic disorders, sleep disorders or intellectual disability) were calculated for individuals with autism (N = 16,126) and non-autism individuals (N = 654,977). Individuals were further stratified based on the age at the first autism diagnoses and comorbid diagnoses up to the age of 16 were compared. RESULTS: Most comorbidities were significantly associated with birth year and sex. Female/male odds ratios for 8 of 11 comorbid conditions were up to 67% higher than the corresponding odds ratios in the non-autism population, including conditions that are generally more common in males than in females as well as conditions that are more common in females. All comorbidity rates were significantly associated with the age at the first autism diagnosis, which was a stronger predictor than sex and birth year for 8 conditions. CONCLUSIONS: Comorbidity rates for females exceed what would be expected based on the sex ratios among non-autistic individuals, indicating that the association between autism and comorbidity is stronger in females. Comorbidity rates are also highly dependent on the age at the first autism diagnosis, which may contribute to autism heterogeneity in research and clinical practice.

Long-Term Metabolic Monitoring of Youths Treated with Second-Generation Antipsychotics 5 Years after Publication of the CAMESA Guidelines Are We Making Progress? Surveillance Métabolique à Long Terme des Jeunes Traités par Antipsychotiques de Deuxième Génération, Cinq ans Après la publication des Lignes Directrices Camesa: Faisons-Nous des Progrès?

OBJECTIVE: The potential metabolic adverse effects of second-generation antipsychotics (SGA) need to be monitored. The Canadian Alliance for Monitoring Effectiveness and Safety of Antipsychotics (CAMESA) offers guidelines for this purpose. We aimed to evaluate the long-term rates of youths receiving monitoring in mental health clinics and document the factors that may influence them. METHOD: The charts of 180 patients (13.3 ± 3.1 years, 54.4% males) receiving SGA treatment for the first time between January 2016 and June 2018 were reviewed. Monitoring was divided into baseline and 1- to 6-month and 9- to 24-month periods. Population under study was stratified into children (4 to 12 years) and adolescents (13 to 18 years). Sociodemographic characteristics, psychiatric diagnosis and comorbidities, prescribed SGAs and comedications, anthropometric measures (AM), blood pressure (BP), blood tests (BT), electrocardiogram, and the psychiatrist's years of practice were collected. Cross tables were used to present the monitoring rates. Categories were compared by covariate analysis. Rates of patients monitored across categories were compared using Fisher exact test. RESULTS: Monitoring rates for AM, BT, and BP were 55%, 47.8%, and 46.7% at baseline; 50%, 41.7%, and 45.2% at 1 to 6 months; and 47.2%, 41.5%, and 40.6% at 9 to 24 months, respectively. Higher monitoring rates were significantly associated with adolescent status (baseline, 1 to 6 months), a diagnosis of psychotic and/or affective disorder (baseline, 1 to 6 months, 9 to 24 months), having ≤1 psychiatric comorbidities (1 to 6 months), high SGA dose (baseline, 1 to 6 months), and clinician's experience (baseline, 9 to 24 months). Significantly lower monitoring rates were associated with the psychostimulant/atomoxetine comedication (baseline, 1 to 6 months, 9 to 24 months). CONCLUSION: Five years after publication of the CAMESA guidelines, metabolic monitoring is conducted for less than half of patients. In our sample, age, diagnostic category, psychiatric comorbidities, SGA dose, clinician's experience, and comedications influenced the monitoring rates. Major progress still needs to be made before reaching a satisfactory level of monitoring.

Should we change targets and methods of early intervention in autism, in favor of a strengths-based education?

Early intensive behavioral intervention (EIBI) and its recent variant, naturalist developmental behavioral intervention (NDBI) aim to increase socialization and communication, and to decrease repetitive and challenging behaviors in preschool age autistic children. These behaviorist techniques are based on the precocity and intensity of the intervention, face-to-face interaction, errorless learning, and information fragmentation. Once considered to be "scientifically proven", the efficacy of these approaches has been called into question in the last decade due to poor-quality data, small effects, low cost-efficiency, and the evolution of ethical and societal standards. Grounded on a reappraisal of the genetic and cognitive neuroscience of autism, we question three aspects of EIBI/NDBI: their focus on prerequisites for typical socio-communicative behaviors, their lack of consideration of autistic language development and learning modes, and their negative view of repetitive behaviors and restricted interests. We propose alternative predictions for empirical validation, based on the strengths of prototypical autistic children: (a) their non-verbal intelligence should be normally distributed and within the normal range; (b) improving access to non-communicative verbal and written auditory language material should favor their subsequent speech development and

Face perception develops similarly across viewpoint in children and adolescents with and without autism spectrum disorder.

Atypical face perception has been associated with the socio-communicative difficulties that characterize autism spectrum disorder (ASD). Growing evidence, however, suggests that a widespread impairment in face perception is not as common as once thought. One important issue arising with the interpretation of this literature is the relationship between face processing and a more general perceptual tendency to focus on local rather than global information. Previous work has demonstrated that when discriminating faces presented from the same view, older adolescents and adults with ASD perform similarly to typically developing individuals. When faces are presented from different views, however, they perform more poorly-specifically, when access to local cues is minimized. In this study, we assessed the cross-sectional development of face identity discrimination across viewpoint using same- and different-view conditions in children and adolescents with and without ASD. Contrary to the findings in adults, our results revealed that all participants experienced greater difficulty identifying faces from different views than from same views, and demonstrated similar age-expected improvements in performance across tasks. These results suggest that differences in face discrimination across views may only emerge beyond the age of 15 years in ASD.

SYN2 is an autism predisposing gene: loss-of-function mutations alter synaptic vesicle cycling and axon outgrowth.

An increasing number of genes predisposing to autism spectrum disorders (ASDs) has been identified, many of which are implicated in synaptic function. This 'synaptic autism pathway' notably includes disruption of SYN1 that is associated with epilepsy, autism and abnormal behavior in both human and mice models. Synapsins constitute a multigene family of neuron-specific phosphoproteins (SYN1-3) present in the majority of synapses where they are implicated in the regulation of neurotransmitter release and synaptogenesis. Synapsins I and II, the major Syn isoforms in the adult brain, display partially overlapping functions and defects in both isoforms are associated with epilepsy and autistic-like behavior in mice. In this study, we show that nonsense (A94fs199X) and missense (Y236S and G464R) mutations in SYN2 are associated with ASD in humans. The phenotype is apparent in males. Female carriers of SYN2 mutations are unaffected, suggesting that SYN2 is another example of autosomal sex-limited expression in ASD. When expressed in SYN2  knockout neurons, wild-type human Syn II fully rescues the SYN2 knockout phenotype, whereas the nonsense mutant is not expressed and the missense mutants are virtually unable to modify the SYN2 knockout phenotype. These results identify for the first time SYN2  as a novel predisposing gene for ASD and strengthen the hypothesis that a disturbance of synaptic homeostasis underlies ASD.

A de novo frameshift mutation in chromodomain helicase DNA-binding domain 8 (CHD8): A case report and literature review.

Mutations in chromodomain helicase DNA-binding domain 8 (CHD8) have been identified in independent genotyping studies of autism spectrum disorder. To better understand the phenotype associated with CHD8 mutations, we genotyped all CHD8 exons in carefully assessed cohorts of autism (n = 142), schizophrenia (SCZ; n = 143), and intellectual disability (ID; n = 94). We identified one frameshift mutation, seven non-synonymous variants, and six synonymous variants. The frameshift mutation, p.Asn2092Lysfs*2, which creates a premature stop codon leading to the loss of 212 amino acids of the protein, was from an autism case on whom we present multiple clinical assessments and pharmacological treatments spanning more than 10 years. RNA and protein analysis support a model where the transcript generated from the mutant allele results in haploinsufficiency of CHD8. This case report supports the association of CHD8 mutations with classical autism, macrocephaly, infantile hypotonia, speech delay, lack of major ID, and psychopathology in late adolescence caused by insufficient dosage of CHD8. Review of 16 other CHD8 mutation cases suggests that clinical features and their severity vary considerably across individuals; however, these data support a CHD8 mutation syndrome, further highlighting the importance of genomic medicine to guide clinical assessment and treatment.

[Is autism a different kind of intelligence? New insights from cognitive neurosciences]. / L'autisme, une autre intelligence.

After being considered a mental disorder for years, then a neurodevelopmental handicap, autism is increasingly being considered a human variant that sometimes involves extreme adaptive advantages and disadvantages. This point of view partly emerges from the fact that autistics perform certain human tasks at the same level, and in some cases even better than neurotypical persons. Furthermore, they perform these tasks using cognitive strategies and cerebral allocations that are different from the majority of humans. We will present some empirical and theoretical cognitive neuroscience studies from our group that support this school of thought.

Novel VPS13B Mutations in Three Large Pakistani Cohen Syndrome Families Suggests a Baloch Variant with Autistic-Like Features.

BACKGROUND: Cohen Syndrome (COH1) is a rare autosomal recessive disorder, principally identified by ocular, neural and muscular deficits. We identified three large consanguineous Pakistani families with intellectual disability and in some cases with autistic traits. METHODS: Clinical assessments were performed in order to allow comparison of clinical features with other VPS13B mutations. Homozygosity mapping followed by whole exome sequencing and Sanger sequencing strategies were used to identify disease-related mutations. RESULTS: We identified two novel homozygous deletion mutations in VPS13B, firstly a 1 bp deletion, NM_017890.4:c.6879delT; p.Phe2293Leufs*24, and secondly a deletion of exons 37-40, which co-segregate with affected status. In addition to COH1-related traits, autistic features were reported in a number of family members, contrasting with the "friendly" demeanour often associated with COH1. The c.6879delT mutation is present in two families from different regions of the country, but both from the Baloch sub-ethnic group, and with a shared haplotype, indicating a founder effect among the Baloch population. CONCLUSION: We suspect that the c.6879delT mutation may be a common cause of COH1 and similar phenotypes among the Baloch population. Additionally, most of the individuals with the c.6879delT mutation in these two families also present with autistic like traits, and suggests that this variant may lead to a distinct autistic-like COH1 subgroup.

[Is psychiatry relevant in autism? A brief historical perspective on the role of psychiatry in diagnosis, and support to autistic people]. / Considérations sur la place de la psychiatrie en autisme, à partir de l'histoire récente des rôles professionnels vis-à-vis de l'autisme au Québec.

Based on an overview of the recent history of professional roles in autism diagnosis and support in the province of Quebec, this paper supports the view that hearing what autistic people say, combined with interdisciplinary, but hierarchically ruled task sharing in clinical settings, and to a pacific confrontation between scientific and clinical demands, prevents the high jacking of autism for corporatist or ideological purposes.

Autistic preschoolers display reduced attention orientation for competition but intact facilitation from a parallel competitor: Eye-tracking and behavioral data.

LAY ABSTRACT: Recent research suggests that we might have underestimated the social motivation of autistic individuals. Autistic children might be engaged in a social situation, even if they seem not to be attending to people in a typical way. Our study investigated how young autistic children behave in a "parallel" situation, which we call "parallel competition," where people participate in friendly contests side-by-side but without direct interaction. First, we used eye-tracking technology to observe how much autistic children pay attention to two video scenarios: one depicting parallel competition, and the other where individuals play directly with each other. The results showed that autistic children looked less toward the parallel competition video than their typically developing peers. However, when autistic children took part in parallel competitions themselves, playing physical and cognitive games against a teacher, their performance improved relative to playing individually just as much as their typically developing peers. This suggests that even though autistic children pay attention to social events differently, they can still benefit from the presence of others. These findings suggest complementing traditional cooperative activities by incorporating parallel activities into educational programs for young autistic children. By doing so, we can create more inclusive learning environments for these children.

Enhanced interest in letters and numbers in autistic children.

BACKGROUND: An intense and precocious interest in written material, together with a discrepancy between decoding and reading comprehension skills are defining criteria for hyperlexia, which is found in up to 20% of autistic individuals. It may represent the extreme end of a broader interest in written material in autism. This study examines the magnitude and nature of the interest in written material in a large population of autistic and non-autistic children. METHODS: All 701 children (391 autistic, 310 non-autistic) under the age of 7 referred to an autism assessment clinic over a span of 4 years were included. Ordinal logistic regressions assessed the association between diagnosis and the level of interest in letters and numbers. A nested sample of parents of 138 autistic, 99 non-autistic clinical, and 76 typically developing (TD) children completed a detailed questionnaire. Cox proportional hazards models analyzed the age of emergence of these interests. Linear regressions evaluated the association between diagnosis and interest level. The frequency of each behaviour showing interest and competence with letters and numbers were compared. RESULTS: In the two studies, 22 to 37% of autistic children had an intense or exclusive interest in letters. The odds of having a greater interest in letters was 2.78 times higher for autistic children than for non-autistic clinical children of the same age, and 3.49 times higher for the interest in numbers, even if 76% of autistic children were minimally or non-verbal. The age of emergence of these interests did not differ between autistic and TD children and did not depend on their level of oral language. Non-autistic children showed more interest in letters within a social context. LIMITATIONS: The study holds limitations inherent to the use of a phone questionnaire with caregivers and missing sociodemographic information. CONCLUSIONS: The emergence of the interest of autistic children toward written language is contemporaneous to the moment in their development where they display a strong deficit in oral language. Together with recent demonstrations of non-social development of oral language in some autistic children, precocious and intense interest in written material suggests that language acquisition in autism may follow an alternative developmental pathway.

Clinical correlates of diagnostic certainty in children and youths with Autistic Disorder.

BACKGROUND: Clinicians diagnosing autism rely on diagnostic criteria and instruments in combination with an implicit knowledge based on clinical expertise of the specific signs and presentations associated with the condition. This implicit knowledge influences how diagnostic criteria are interpreted, but it cannot be directly observed. Instead, insight into clinicians' understanding of autism can be gained by investigating their diagnostic certainty. Modest correlations between the certainty of an autism diagnosis and symptom load have been previously reported. Here, we investigated the associations of diagnostic certainty with specific items of the ADOS as well as other clinical features including head circumference. METHODS: Phenotypic data from the Simons Simplex Collection was used to investigate clinical correlates of diagnostic certainty in individuals diagnosed with Autistic Disorder (n = 1511, age 4 to 18 years). Participants were stratified by the ADOS module used to evaluate them. We investigated how diagnostic certainty was associated with total ADOS scores, age, and ADOS module. We calculated the odds-ratios of being diagnosed with the highest possible certainty given the presence or absence of different signs during the ADOS evaluation. Associations between diagnostic certainty and other cognitive and clinical variables were also assessed. RESULTS: In each ADOS module, some items showed a larger association with diagnostic certainty than others. Head circumference was significantly higher for individuals with the highest certainty rating across all three ADOS modules. In turn, head circumference was positively correlated with some of the ADOS items that were associated with diagnostic certainty, and was negatively correlated with verbal/nonverbal IQ ratio among those assessed with ADOS module 2. LIMITATIONS: The investigated cohort was heterogeneous, e.g. in terms of age, IQ, language level, and total ADOS score, which could impede the identification of associations that only exist in a subgroup of the population. The variability of the certainty ratings in the sample was low, limiting the power to identify potential associations with other variables. Additionally, the scoring of diagnostic certainty may vary between clinicians. CONCLUSION: Some ADOS items may better capture the signs that are most associated with clinicians' implicit knowledge of Autistic Disorder. If replicated in future studies, new diagnostic instruments with differentiated weighting of signs may be needed to better reflect this, possibly resulting in better specificity in standardized assessments.

Integrating genomic variants and developmental milestones to predict cognitive and adaptive outcomes in autistic children.

Although the first signs of autism are often observed as early as 18-36 months of age, there is a broad uncertainty regarding future development, and clinicians lack predictive tools to identify those who will later be diagnosed with co-occurring intellectual disability (ID). Here, we developed predictive models of ID in autistic children (n=5,633 from three cohorts), integrating different classes of genetic variants alongside developmental milestones. The integrated model yielded an AUC ROC=0.65, with this predictive performance cross-validated and generalised across cohorts. Positive predictive values reached up to 55%, accurately identifying 10% of ID cases. The ability to stratify the probabilities of ID using genetic variants was up to twofold greater in individuals with delayed milestones compared to those with typical development. These findings underscore the potential of models in neurodevelopmental medicine that integrate genomics and clinical observations to predict outcomes and target interventions.