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.

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.

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.

Development, psychometric evaluation, and factor analysis of an instrument measuring quality of life in autistic preschoolers

INTRODUCTION

Early interventions for autistic children should target their quality of life (QoL) but require adapted measures. The association of a child's temperament and parental characteristics with the QoL of autistic children remains unknown.

METHODS

We constructed an autism module based on a thematic analysis, a Delphi survey with experts, and a pre-test with parents to be completed alongside the proxy version of the PedsQL 4.0. We explored compliance, responsiveness, internal consistency, convergent validity, and factor structure with 157 parents of autistic preschool children. We examined the association between child and parental characteristics with the QoL of autistic children using correlation analysis, principal component analysis, hierarchical ascending classification, and linear regression. Sociodemographic information was collected via multiple choice questions, autism severity via Autism Diagnostic Observation Schedule (ADOS) scores, and parental acceptance and child's temperament via the Acceptance and Action Questionnaire and the Emotionality, Activity, and Sociability.

RESULTS

An autism module comprised of 27 items emerged. Psychometric evaluation resulted in a 24-item autism module with good internal consistency and significant convergent validity. ADOS total score was not significantly related to QoL, contrary to children's sleep issues, children's emotionality, and parental acceptance.

CONCLUSIONS

The autism module is a reliable QoL proxy measure for autistic preschool children. Results suggest parental interventions targeting children's QoL.

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.

Language acquisition can be truly atypical in autism: Beyond joint attention

Language profiles in autism are variable and atypical, with frequent speech onset delays, but also, in some cases, unusually steep growth of structural language skills. Joint attention is often seen as a major predictor of language in autism, even though low joint attention is a core characteristic of autism, independent of language levels. In this systematic review of 71 studies, we ask whether, in autism, joint attention predicts advanced or only early language skills, and whether it may be independent of language outcomes. We consider only conservative estimates, and flag studies that include heterogenous samples or no control for non-verbal cognition. Our review suggests that joint attention plays a pivotal role for the emergence of language, but is also consistent with the idea that some autistic children may acquire language independently of joint attention skills. We propose that language in autism should not necessarily be modelled as a quantitative or chronological deviation from typical language development, and outline directions to bring autistic individuals' atypicality within the focus of scientific inquiry.

Prototypical autism: New diagnostic criteria and asymmetrical bifurcation model

The current "autism spectrum" DSM 5 diagnostic criteria and autism standardized diagnostic instruments promote considerable heterogeneity or clinical indecision and may be detrimental to the advancement of fundamental research on autism mechanisms. To increase clinical specificity and reorient research towards core autistic presentations, we propose new diagnostic criteria for prototypical autism during the age of 2- to 5-years. We include autism within other non-dominant, familiarly aggregated phenomena sharing asymmetrical developmental bifurcations, such as twin pregnancy, left handedness, and breech presentation/delivery. Following this model, nature, trajectory, and positive/negative signs structure of autism would result from the polarized problem of whether or not language and information is processed in a socially biased manner. Prototypical autism would follow a canonical developmental trajectory by which a gradual decline in social bias in the processing of incoming information, overtly beginning at the end of the first year, bifurcates into a prototypical autistic presentation in the second half of the second year of life. This bifurcation event is followed by a plateau, in which these atypicalities show maximal stringency and distinctiveness, and then ultimately, in most cases, by partial normalization. During the plateau period, the orientation towards, and processing of, information is considerably modified, with an absence of bias for social information, contrasting with a high level of interest in complex, unbiased information, independently of its social or non-social nature. Integrating autism into asymmetrical developmental bifurcations would explain the absence of deleterious neurological and genetic markers and the presence of familial transmission in canonical autistic presentations.

Genesis, modelling and methodological remedies to autism heterogeneity

Diagnostic criteria used in autism research have undergone a shift towards the inclusion of a larger population, paralleled by increasing, but variable, estimates of autism prevalence across clinical settings and continents. A categorical diagnosis of autism spectrum disorder is now consistent with large variations in language, intelligence, comorbidity, and severity, leading to a heterogeneous sample of individuals, increasingly distant from the initial prototypical descriptions. We review the history of autism diagnosis and subtyping, and the evidence of heterogeneity in autism at the cognitive, neurological, and genetic levels. We describe two strategies to address the problem of heterogeneity: clustering, and truncated-compartmentalized enrollment strategy based on prototype recognition. The advances made using clustering methods have been modest. We present an alternative, new strategy for dissecting autism heterogeneity, emphasizing incorporation of prototypical samples in research cohorts, comparison of subgroups defined by specific ranges of values for the clinical specifiers, and retesting the generality of neurobiological results considered to be acquired from the entire autism spectrum on prototypical cohorts defined by narrow specifiers values.

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 (PedsQL^TM4.0) 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 PedsQL^TM4.0 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.

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.

Using developmental regression to reorganize the clinical importance of autistic atypicalities

Early regression (ER) is often reported in autistic children with a prototypical phenotype and has been proposed as a possible pathognomonic sign present in most autistic children. Despite the uncertainties attached to its definition and report, using ER to anchor the autism phenotype could help identify the signs that best contribute to an autism diagnosis. We extracted retrospective data from 1547 autistic children between the ages of 6 and 18 years from the Simons Simplex collection. Logistic regression identified the atypicalities associated with a history of ER. Stepwise variable selection using logistic regression analysis followed by a bootstrap procedure of 1000 iterations identified the cluster of atypicalities best associated with ER. Linear and logistic regressions measured the association between combinations of atypicalities within the identified cluster and adaptative behaviors, diagnostic areas of severity, and other categories. Seven atypicalities significantly increased the likelihood of having experienced ER (OR = 1.73-2.13). Four ("hand leading-ever", "pronominal reversal-ever", "never shakes head at age 4-5" and "stereotypic use of objects or interest in parts of objects-ever"), when grouped together, best characterized the phenotype of verbal autistic children with ER. This clustering of signs was associated with certain persistent language difficulties, higher summary scores on a diagnostic scale for autism, and greater odds of receiving an "autistic disorder" diagnosis instead of another pervasive developmental disorder (PDD) diagnosis. These results raise questions about using language as a clinical specifier, defining cross-sectional signs independent of their relationship with an early developmental trajectory, and relying on polythetic criteria or equivalent weighted autistic atypicalities.

Representativeness of autistic samples in studies recruiting through social media

Survey-based research with recruitment through online channels is a convenient way to obtain large samples and has recently been increasingly used in autism research. However, sampling from online channels may be associated with a high risk of sampling bias causing findings not to be generalizable to the autism population. Here we examined autism studies that have sampled on social media for markers of sampling bias. Most samples showed one or more indicators of sampling bias, in the form of reversed sex ratio, higher employment rates, higher education level, lower fraction of individuals with intellectual disability, and later age of diagnosis than would be expected when comparing with for example population study results from published research. Findings from many of the included studies are therefore difficult to generalize to the broader autism population. Suggestions for how research strategies may be adapted to address some of the problems are discussed. LAY SUMMARY: Online surveys offer a convenient way to recruit large numbers of participants for autism research. However, the resulting samples may not fully reflect the autism population. Here we investigated the samples of 36 autism studies that recruited participants online and found that the demographic composition tended to deviate from what has been reported about the autism population in previous research. The results may thus not be generalizable to autism in general.

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.

Positive, negative, neutral-or unknown? The perceived valence of emotions expressed by young autistic children in a novel context suited to autism

Starting early in life, autistics are characterized as having atypical facial expressions, as well as decreased positive and increased negative affect. The literature on autistic facial expressions remains small, however, with disparate methods and results suggesting limited understanding of common autistic emotions. Furthermore, unlike non-autistics’ emotions, autistics’ emotions have been assessed without considering this population’s characteristics. In this study, the valence of young children’s facial expressions was thus rated as positive, negative, neutral, or “unknown”—a term for perceived emotions observers do not understand. Facial expressions were assessed using the Montreal Stimulating Play Situation, a context incorporating potential autistic interests. Comparing 37 autistic and 39 typical young (27–56 months) age-matched children, we found no group differences in expressed positive, negative, and neutral emotions. We did find differences in unknown emotions, which were unique to the autistic group. Preliminary data also showed that autistic children’s repetitive behaviors co-occurred with positive, neutral, and unknown emotions, but not with negative emotions. In a novel context that considers their characteristics, we did not find decreased positive or increased negative emotions in young autistic children. Instead, they uniquely expressed emotions perceived as unknown, showing the need to improve our understanding of their full emotional repertoire.

Childhood diagnoses in individuals identified as autistics in adulthood

Background

Autism is a developmental condition, where symptoms are expected to occur in childhood, but a significant number of individuals are diagnosed with autism for the first time in adulthood. Here, we examine diagnoses given in childhood among individuals that are diagnosed with autism in adulthood, to investigate whether the late autism diagnosis might be explained by misdiagnosis in childhood or diagnostic overshadowing.

Methods

Through the Danish National Patient Registry, we identified individuals diagnosed with autism in adulthood (N = 2199), as well as a control sample with no records of an autism diagnosis (N = 460,798) and calculated how many had received different psychiatric or neurological diagnoses in childhood.

Results

We found that most childhood diagnoses were overrepresented in those with an adult autism diagnosis, and attention-deficit hyperactivity disorder, affective disorders, anxiety, and stress disorders were the most prevalent childhood conditions in this group. However, 69% of males and 61% of females with adult autism diagnoses were not found to have received any of the investigated diagnoses before 18 years of age, and most childhood diagnoses were given after the age of 12.

Limitations

Milder to moderate cases of psychiatric conditions that have been solely treated by family physicians or school psychologists may not be fully included in our dataset. The study is based on data from the Danish health care system, and further research is needed to assess whether the findings can be generalized to other countries.

Conclusion

A majority of those with an adult autism diagnosis had no records of having received any of the investigated diagnoses in childhood. In these cases, the late autism diagnosis is therefore unlikely to be explained by either misdiagnosis or overshadowing. This result is at odds with the prevailing notion that autistic symptoms tend to diminish with age. Therefore, further research is warranted to examine how and if early signs of autism may have manifested among these individuals, and how similar they are to autistic people diagnosed earlier in their development.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13229-021-00478-y.

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.

Connectivity alterations in autism reflect functional idiosyncrasy

Autism spectrum disorder (ASD) is commonly understood as an alteration of brain networks, yet case-control analyses against typically-developing controls (TD) have yielded inconsistent results. Here, we devised a novel approach to profile the inter-individual variability in functional network organization and tested whether such idiosyncrasy contributes to connectivity alterations in ASD. Studying a multi-centric dataset with 157 ASD and 172 TD, we obtained robust evidence for increased idiosyncrasy in ASD relative to TD in default mode, somatomotor and attention networks, but also reduced idiosyncrasy in lateral temporal cortices. Idiosyncrasy increased with age and significantly correlated with symptom severity in ASD. Furthermore, while patterns of functional idiosyncrasy were not correlated with ASD-related cortical thickness alterations, they co-localized with the expression patterns of ASD risk genes. Notably, we could demonstrate that patterns of atypical idiosyncrasy in ASD closely overlapped with connectivity alterations that are measurable with conventional case-control designs and may, thus, be a principal driver of inconsistency in the autism connectomics literature. These findings support important interactions between inter-individual heterogeneity in autism and functional signatures. Our findings provide novel biomarkers to study atypical brain development and may consolidate prior research findings on the variable nature of connectome level anomalies in autism.

Positive and differential diagnosis of autism in verbal women of typical intelligence: A Delphi study

Diagnostic criteria for autism are relatively vague, and may lead to over and underdiagnosis when applied without clinical expertise. Indeed, autism is best reliably identified by experienced clinicians who take into account qualitative aspects of the condition. When assessing for autism in women, little guidance exists to support clinicians deciding whether to attribute adaptive difficulties to autism, a psychiatric condition, or both. The purpose of this study was therefore to propose guidelines for clinicians assessing for autism in women. To do this, we aimed to describe the clinical expertise involved in making positive and differential diagnoses of autism in adult women of typical intelligence. We interviewed 20 experienced clinicians from seven countries. We then elaborated Delphi statements summarizing participant views on the topic, which our participants rated. We obtained a final list of 37 suggested clinical guidelines to improve specificity and sensitivity of autism diagnosis in women. Participants had developed individual assessment strategies, although much overlap existed across participants. Participants provided insight to differentiate autism from post-traumatic stress disorder and Borderline Personality Disorder, and underlined the importance of being able to make differential diagnoses particularly in cases where non-autistic people had strongly self-identified with the spectrum.

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.

A radical change in our autism research strategy is needed: Back to prototypes

The evolution of autism diagnosis, from its discovery to its current delineation using standardized instruments, has been paralleled by a steady increase in its prevalence and heterogeneity. In clinical settings, the diagnosis of autism is now too vague to specify the type of support required by the concerned individuals. In research, the inclusion of individuals categorically defined by over-inclusive, polythetic criteria in autism cohorts results in a population whose heterogeneity runs contrary to the advancement of scientific progress. Investigating individuals sharing only a trivial resemblance produces a large-scale type-2 error (not finding differences between autistic and dominant population) rather than detecting mechanistic differences to explain their phenotypic divergences. The dimensional approach of autism proposed to cure the disease of its categorical diagnosis is plagued by the arbitrariness of the dimensions under study. Here, we argue that an emphasis on the reliability rather than specificity of diagnostic criteria and the misuse of diagnostic instruments, which ignore the recognition of a prototype, leads to confound autism with the entire range of neurodevelopmental conditions and personality variants. We propose centering research on cohorts in which individuals are selected based on their expert judged prototypicality to advance the theoretical and practical pervasive issues pertaining to autism diagnostic thresholds. Reversing the current research strategy by giving more weight to specificity than reliability should increase our ability to discover the mechanisms of autism. LAY SUMMARY: Scientific research into the causes of autism and its mechanisms is carried out on large cohorts of people who are less and less different from the general population. This historical trend may explain the poor harvest of results obtained. Services and intervention are provided according to a diagnosis that now encompasses extremely different individuals. Last, we accept as a biological reality the constant increase over the years in the proportion of autistic people among the general population. These drifts are made possible by the attribution of a diagnosis of autism to people who meet vague criteria, rather than to people who experienced clinicians recognize as autistic. We propose to change our research strategy by focusing on the study of the latter, fewer in number, but more representative of the "prototype" of autism. To do this, it is necessary to clearly distinguish the population on which the research is carried out from that to which we provide support. People must receive services according to their needs, and not according to the clarity of their diagnosis.

Bayonet-shaped language development in autism with regression: a retrospective study

Background

Language delay is one of the major referral criteria for an autism evaluation. Once an autism spectrum diagnosis is established, the language prognosis is among the main parental concerns. Early language regression (ELR) is observed by 10–50% of parents but its relevance to late language level and socio-communicative ability is uncertain. This study aimed to establish the predictive value of ELR on the progression of language development and socio-communicative outcomes to guide clinicians in addressing parents’ concerns at the time of diagnosis.

Methods

We used socio-communicative, language, and cognitive data of 2,047 autism spectrum participants from the Simons Simplex Collection, aged 4–18 years (mean = 9 years; SD = 3.6). Cox proportional hazard and logistic regression models were used to evaluate the effect of ELR on language milestones and the probability of using complex and flexible language, as defined by the choice of ADOS module at enrollment. Linear models were then used to evaluate the relationship of ELR and non-verbal IQ with socio-communicative and language levels.

Results

ELR is associated with earlier language milestones but delayed attainment of fluent, complex, and flexible language. However, this language outcome can be expected for almost all autistic children without intellectual disability at 18 years of age. It is mostly influenced by non-verbal IQ, not ELR. The language and socio-communicative level of participants with flexible language, as measured by the Vineland and ADOS socio-communicative subscales, was not affected by ELR.

Limitations

This study is based on a relatively coarse measure of ultimate language level and relies on retrospective reporting of early language milestones and ELR. It does not prospectively document the age at which language catches up, the relationship between ELR and other behavioral areas of regression, nor the effects of intervention.

Conclusions

For autistic individuals with ELR and a normal level of non-verbal intelligence, language development follows a “bayonet shape” trajectory: early first words followed by regression, a plateau with limited progress, and then language catch up.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13229-021-00444-8.

Effect Sizes of Deletions and Duplications on Autism Risk Across the Genome

OBJECTIVE

Deleterious copy number variants (CNVs) are identified in up to 20% of individuals with autism. However, levels of autism risk conferred by most rare CNVs remain unknown. The authors recently developed statistical models to estimate the effect size on IQ of all CNVs, including undocumented ones. In this study, the authors extended this model to autism susceptibility.

METHODS

The authors identified CNVs in two autism populations (Simons Simplex Collection and MSSNG) and two unselected populations (IMAGEN and Saguenay Youth Study). Statistical models were used to test nine quantitative variables associated with genes encompassed in CNVs to explain their effects on IQ, autism susceptibility, and behavioral domains.

RESULTS

The "probability of being loss-of-function intolerant" (pLI) best explains the effect of CNVs on IQ and autism risk. Deleting 1 point of pLI decreases IQ by 2.6 points in autism and unselected populations. The effect of duplications on IQ is threefold smaller. Autism susceptibility increases when deleting or duplicating any point of pLI. This is true for individuals with high or low IQ and after removing de novo and known recurrent neuropsychiatric CNVs. When CNV effects on IQ are accounted for, autism susceptibility remains mostly unchanged for duplications but decreases for deletions. Model estimates for autism risk overlap with previously published observations. Deletions and duplications differentially affect social communication, behavior, and phonological memory, whereas both equally affect motor skills.

CONCLUSIONS

Autism risk conferred by duplications is less influenced by IQ compared with deletions. The model applied in this study, trained on CNVs encompassing >4,500 genes, suggests highly polygenic properties of gene dosage with respect to autism risk and IQ loss. These models will help to interpret CNVs identified in the clinic.

Age of Speech Onset in Autism Relates to Structural Connectivity in the Language Network

Speech onset delays (SOD) and language atypicalities are central aspects of the autism spectrum (AS), despite not being included in the categorical diagnosis of AS. Previous studies separating participants according to speech onset history have shown distinct patterns of brain organization and activation in perceptual tasks. One major white matter tract, the arcuate fasciculus (AF), connects the posterior temporal and left frontal language regions. Here, we used anatomical brain imaging to investigate the properties of the AF in adolescent and adult autistic individuals with typical levels of intelligence who differed by age of speech onset. The left AF of the AS group showed a significantly smaller volume than that of the nonautistic group. Such a reduction in volume was only present in the younger group. This result was driven by the autistic group without SOD (SOD−), despite their typical age of speech onset. The autistic group with SOD (SOD+) showed a more typical AF as adults relative to matched controls. This suggests that, along with multiple studies in AS-SOD+ individuals, atypical brain reorganization is observable in the 2 major AS subgroups and that such reorganization applies mostly to the language regions in SOD− and perceptual regions in SOD+ individuals.

Interests and Strengths in Autism, Useful but Misunderstood: A Pragmatic Case-Study

Background

Studies on autistic strengths are often focused on what they reveal about autistic intelligence and, in some cases, exceptional and atypical reasoning abilities. An emerging research trend has demonstrated how interests and strengths often evident in autism can be harnessed in interventions to promote the well-being, adaptive, academic and professional success of autistic people. However, abilities in certain domains may be accompanied by major limitations in others, as well as psychiatric and behavioral issues, which may challenge their inclusion in support programs.

Objectives

To provide an in-depth, pragmatic, real-life example of the psychological and psychiatric management of interests and strengths in an autistic adolescent.

Method

An autistic teenager, C.A., with above-average calendar calculation and musical abilities, received psychiatric, neuropsychological, and language standardized and clinical assessments, combined with a measurement of his musical and calendar calculation abilities. C.A. and his parents then received psychiatric and psychological support over a 14-month period, targeting their perceptions of C.A.'s interests, strengths, and co-occurring difficulties.

Results

C.A. had a verbal IQ within the intellectual disability range and a non-verbal IQ in the low mean range. Modest calendar calculation, absolute pitch, and matrix abilities coexisted with severe receptive and expressive language disorder. The discrepancy between his abilities in areas of strengths and his limitations in other domains led to anxiety, frustration, and sometimes behavioral issues. Displacing the focus from academic performance to interests, as well as promoting the use of his strengths to develop new skills independently of their short-term adaptive benefits yielded positive effects on C.A.'s self-assessment, quality of life, and behavior at follow up.

Discussion

The appealing idea that abilities mostly found in autistic people, such as calendar calculation, can be directly harnessed into academic achievement and lead to paid employment may have detrimental effects, especially when such abilities are modest and associated with other limitations. These abilities should be primarily used to maximize well-being and quality of life, independently of their short-term adaptive function, which may or may not be positive.

Impact of Psychoactive Drug Use on Developing Obesity among Children and Adolescents with Autism Spectrum Diagnosis: A Nested Case-Control Study

BACKGROUND

Obesity in children on the autism spectrum (AS) is becoming a significant health concern. The purpose of this study was to identify the predictors of obesity in a cohort of AS youth and to assess the impact of psychoactive medication use while exploring the second-generation antipsychotics (SGAs) dose-response curve.

STUDY DESIGN

A nested case-control study was conducted using Quebec public administrative databases. Subjects with AS <18 years [≥2 diagnoses International Classification of Diseases: 9th revision (ICD-9): 299.X] were identified (January 1993 to May 2011). Cases were defined as subjects with an obesity diagnosis (ICD-9: 278.X) during the coverage period and matched to 10 controls for age, gender, and follow-up duration. Potential risk factors for obesity (sociodemographic characteristics, other neuropsychiatric conditions, and psychoactive drug use) were evaluated and analyzed using conditional logistic regression.

RESULTS

From a cohort of 5369 AS subjects, we identified 135 obesity cases. Among the different risk factors, only SGAs [rate ratio (RR): 1.04, 95% confidence interval (CI): 1.01-1.07] increased the probability of obesity in multivariate analysis. Exposure for ≥12 months increased significantly the likelihood of obesity (RR: 2.01, 95% CI: 1.18-3.42). Higher risk was observed with chlorpromazine-equivalent daily doses ≥100 mg (RR: 2.20, 95% CI: 1.00-4.84). Among SGA users, concomitant antidepressants (per 30-day exposure) slightly increased the probability (RR: 1.08, 95% CI: 1.01-1.15).

CONCLUSIONS

Longer and higher SGA exposure increased the risk of obesity, which has to be considered in relation to the paucity of evidence supporting long-term psychoactive medication use in AS children. Results highlight the need to promote optimal use and interventions to mitigate metabolic side effects of SGAs in this population.

Tinkering with the vasopressin pathway in autism

Two clinical trials targeting the vasopressin pathway in autism highlight continuing challenges in outcome measures and statistical power.

Autism spectrum disorder

Autism is a frequent, precocious behavioral constellation of social and communicative atypicalities associated with apparently restricted interests and repetitive behavior and paired with an uneven ability profile. Its definition has constantly broadened in the past 75 years, introducing phenotypes increasingly distant from its initial description, heterogeneous in intelligence and speech level, and associated conditions. When it is unassociated with other conditions, its origin is mostly genetic, transmissible, and favored by frequent polymorphisms with small effects present in the general population. Identified de novo rare mutations with large deleterious effects produce phenotypes only loosely related to nonsyndromic autism. Autism is associated with brain reorganization at multiple levels, and with a variant of typical information processing, i.e., the way humans perceive, memorize, manipulate, and attribute emotional value to available information. Its phenotype evolves over the span of life, with an overall reduction of autistic signs, but it still requires some level of support. There is no treatment for this condition; however, it is compatible with high levels of integration into society.

Temporal Changes in Effect Sizes of Studies Comparing Individuals With and Without Autism: A Meta-analysis

Importance

The definition and nature of autism have been highly debated, as exemplified by several revisions of the DSM (DSM-III, DSM-IIIR, DSM-IV, and DSM-5) criteria. There has recently been a move from a categorical view toward a spectrum-based view. These changes have been accompanied by a steady increase in the prevalence of the condition. Changes in the definition of autism that may increase heterogeneity could affect the results of autism research; specifically, a broadening of the population with autism could result in decreasing effect sizes of group comparison studies.

Objective

To examine the correlation between publication year and effect size of autism-control group comparisons across several domains of published autism neurocognitive research.

Data Sources

This meta-analysis investigated 11 meta-analyses obtained through a systematic search of PubMed for meta-analyses published from January 1, 1966, through January 27, 2019, using the search string autism AND (meta-analysis OR meta-analytic). The last search was conducted on January 27, 2019.

Study Selection

Meta-analyses were included if they tested the significance of group differences between individuals with autism and control individuals on a neurocognitive construct. Meta-analyses were only included if the tested group difference was significant and included data with a span of at least 15 years.

Data Extraction and Synthesis

Data were extracted and analyzed according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guideline using fixed-effects models.

Main Outcomes and Measures

Estimated slope of the correlation between publication year and effect size, controlling for differences in methods, sample size, and study quality.

Results

The 11 meta-analyses included data from a total of 27 723 individuals. Demographic data such as sex and age were not available for the entire data set. Seven different psychological and neurologic constructs were analyzed based on data from these meta-analyses. Downward temporal trends for effect size were found for all constructs (slopes: -0.067 to -0.003), with the trend being significant in 5 of 7 cases: emotion recognition (slope: -0.028 [95% CI, -0.048 to -0.007]), theory of mind (-0.045 [95% CI, -0.066 to -0.024]), planning (-0.067 [95% CI, -0.125 to -0.009]), P3b amplitude (-0.048 [95% CI, -0.093 to -0.004]), and brain size (-0.047 [95% CI, -0.077 to -0.016]). In contrast, 3 analogous constructs in schizophrenia, a condition that is also heterogeneous but with no reported increase in prevalence, did not show a similar trend.

Conclusions and Relevance

The findings suggest that differences between individuals with autism and those without the diagnosis have decreased over time and that possible changes in the definition of autism from a narrowly defined and homogenous population toward an inclusive and heterogeneous population may reduce our capacity to build mechanistic models of the condition.

A Developmental Perspective of Global and Local Visual Perception in Autism Spectrum Disorder

Individuals with autism spectrum disorder (ASD) demonstrate superior performances on visuo-spatial tasks emphasizing local information processing; however, findings from studies involving hierarchical stimuli are inconsistent. Wide age ranges and group means complicate their interpretability. Children and adolescents with and without ASD completed a Navon task wherein they identified global and local stimuli composed of either consistent or inconsistent letters. Trajectories of reaction time in global and local conditions were similar within and between groups when consistent and inconsistent stimuli were considered together, but the effect of local-to-global interference was significantly higher in participants with than without ASD. Age was not a significant predictor of local-to-global interference, suggesting that this effect emerges in childhood and persists throughout adolescence in ASD.

An opposite pattern of cognitive performance in autistic individuals with and without alexithymia

Oakley, Brewer, Bird, and Catmur (2016) investigated whether the Reading the Minds in the Eyes Test (RMET) measures emotion recognition rather than theory of mind (ToM). To explore this, 19 participants with autism and 23 controls, matched on alexithymia traits, were tested with the RMET, as well as the ToM Movie for Assessment of Social Cognition (MASC). The authors found a significant difference between the two groups on the MASC but not on the RMET, but dividing the groups based on alexithymia resulted in a significantly lower performance on the RMET but not on the MASC for the alexithymia group. Therefore, they conclude that difficulties on the RMET are associated with alexithymia, not autism, while difficulties on the MASC are associated with autism, not alexithymia. Here we investigated what seems to be opposite patterns of performance on the two cognitive tasks within the autism group, which modified the authors' interpretation of their data. This was examined by correlating the alexithymia scores with the RMET and a subscale of the MASC scores, referred to as the cognitive MASC. We found a negative correlation between the alexithymia score and the RMET score while also finding a positive correlation between the alexithymia score and the cognitive MASC score in the autism group. Such an opposite pattern of performance suggests the presence of distinct patterns of ToM difficulties within the autism group. This also indicates that, contrary to what is reported by Oakley et al., there is an association between alexithymia and the MASC within the autism group. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Reduced multisensory facilitation in adolescents and adults on the Autism Spectrum

Individuals with autism are reported to integrate information from visual and auditory channels in an idiosyncratic way. Multisensory integration (MSI) of simple, non-social stimuli (i.e., flashes and beeps) was evaluated in adolescents and adults with (n = 20) and without autism (n = 19) using a reaction time (RT) paradigm using audio, visual, and audiovisual stimuli. For each participant, the race model analysis compares the RTs on the audiovisual condition to a bound value computed from the unimodal RTs that reflects the effect of redundancy. If the actual audiovisual RTs are significantly faster than this bound, the race model is violated, indicating evidence of MSI. Our results show that the race model violation occurred only for the typically-developing (TD) group. While the TD group shows evidence of MSI, the autism group does not. These results suggest that multisensory integration of simple information, void of social content or complexity, is altered in autism. Individuals with autism may not benefit from the advantage conferred by multisensory stimulation to the same extent as TD individuals. Altered MSI for simple, non-social information may have cascading effects on more complex perceptual processes related to language and behaviour in autism.

Relationships Between Self-Injurious Behaviors, Pain Reactivity, and β-Endorphin in Children and Adolescents With Autism

OBJECTIVE

Autism and certain associated behaviors including self-injurious behaviors (SIB) and atypical pain reactivity have been hypothesized to result from excessive opioid activity. The objective of this study was to examine the relationships between SIB, pain reactivity, and β-endorphin levels in autism.

METHODS

Study participants were recruited between 2007 and 2012 from day care centers and included 74 children and adolescents diagnosed with autism (according to DSM-IV-TR, ICD-10, and CFTMEA) and intellectual disability. Behavioral pain reactivity and SIB were assessed in 3 observational situations (parents at home, 2 caregivers at day care center, a nurse and child psychiatrist during blood drawing) using validated quantitative and qualitative scales. Plasma β-endorphin concentrations were measured in 57 participants using 2 different immunoassay methods.

RESULTS

A high proportion of individuals with autism displayed SIB (50.0% and 70.3% according to parental and caregiver observation, respectively). The most frequent types of SIB were head banging and hand biting. An absence or decrease of overall behavioral pain reactivity was observed in 68.6% and 34.2% of individuals with autism according to parental and caregiver observation, respectively. Those individuals with hyporeactivity to daily life accidental painful stimuli displayed higher rates of self-biting (P < .01, parental evaluation). No significant correlations were observed between β-endorphin level and SIB or pain reactivity assessed in any of the 3 observational situations.

CONCLUSIONS

The absence of any observed relationships between β-endorphin level and SIB or pain reactivity and the conflicting results of prior opioid studies in autism tend to undermine support for the opioid theory of autism. New perspectives are discussed regarding the relationships found in this study between SIB and hyporeactivity to pain.

Use, costs, and predictors of psychiatric healthcare services following an autism spectrum diagnosis: Population-based cohort study

A number of cross-sectional studies report extensive use of psychiatric services and high healthcare costs in autistic youths. However, little is known about how the use of these services evolves from the time of diagnosis, as children grow up. Our objectives were to investigate the use, costs, and predictors of psychiatric services following autism spectrum diagnosis. We built a cohort of 1227 newly diagnosed autism spectrum individuals identified in the Quebec (Canada) Régie de l'assurance maladie du Québec administrative database (January 1998 to December 2010). Mean number and cost per individual of psychiatric healthcare use (hospitalizations, medical visits, psychoactive drug use) were calculated yearly for 5 years following autism spectrum diagnosis. Mean number of psychiatric visits decreased over time by more than threefold (7.5 vs 2.1 visits) from year 1 to year 5, whereas psychoactive drug use increased from 16.0 to 25.2 claims. Psychiatric hospitalizations decreased during follow-up, but still represented the greatest costs per individual (CAD9820 for year 1; CAD4628 for year 5). Antipsychotics represented over 50% of drug costs. Mixed-effect model with repeated measures showed that previous psychoactive drug use was the strongest predictor of greater psychiatric healthcare cost during follow-up (odds ratio: 9.96; 95% confidence interval: 7.58-13.10). These trends contrast with guidelines advocating cautious prescribing of antipsychotics with periodical re-assessment of their benefit.

Detrimental ''Sensitivity'' framework misses the positive performance, role and autonomy of autistic perception

Perception in autism is associated with positive emotions and intense interests, but sensory hypersensitivity represents a limited and poorly representative aspect of what characterizes autistic perception, which is a strength. An enhanced role of perception contributes to written and oral language learning, and to higher-order intelligence. However, perceptual atypicalities are highly domain- and individual-specific, which makes it risky to elaborate general physiological models of autistic perception in the current state of knowledge and phenotype delineation.

Synesthesia & autistic features in a large family: Evidence for spatial imagery as a common factor

BACKGROUND

Autism and synesthesia are neurodevelopmental conditions associated with variants of perceptual processing. They also share some genetic variants and include a large magnitude of intra-categorical variation: 60 types for synesthesia, as well as a spectrum for autism. In order to investigate the relationship between these two phenomena, we investigated the family of FC, an autistic individual who also possess savant abilities and synesthesia manifestations.

METHOD

Autistic symptoms were assessed for the entire sample of participants entering the study (39 individuals) using the SRS. Participants above threshold were evaluated with standardized diagnostic tools. Synesthesia was explored in the entire participating sample using a self-reported questionnaire. Consistency tests were used for participants who reported synesthetic manifestations.

RESULTS

In addition to FC, four individuals with ASD were detected. Fifteen participants self-reported synesthesia (15 sequence-space, 4 sound-shape, 4 day-color), among which nine sequence-space synesthetes satisfied the consistency criteria. Two participants possess both autism and synesthesia.

CONCLUSION

This family illustrates the co-segregation of autism and synesthesia. This co-segregation is in favour of a partially overlapping genetic predisposition for both conditions, but also authorizes a large variety of manifestations in both conditions. The high prevalence of sequence-space synesthesia in this family strengthens the previous assumption that this form of synesthesia may be linked to autism. We discuss the potential role of spatial imagery in the development of this form of synesthesia and savant abilities.

What interests young autistic children? An exploratory study of object exploration and repetitive behavior

Behaviors characterized as restricted and repetitive (RRBs) in autism manifest in diverse ways, from motor mannerisms to intense interests, and are diagnostically defined as interfering with functioning. A variety of early autism interventions target RRBs as preoccupying young autistic children to the detriment of exploration and learning opportunities. In an exploratory study, we developed a novel stimulating play situation including objects of potential interest to autistic children, then investigated repetitive behaviors and object explorations in 49 autistic and 43 age-matched typical young children (20-69 months). Autistic children displayed significantly increased overall frequency and duration of repetitive behaviors, as well as increased specific repetitive behaviors. However, groups did not significantly differ in frequency and duration of overall object explorations, in number of different objects explored, or in explorations of specific objects. Exploratory analyses found similar or greater exploration of literacy-related objects in autistic compared to typical children. Correlations between repetitive behaviors and object explorations (their frequency and duration) revealed positive, not negative, associations in both groups. Our findings, from a novel situation incorporating potential autistic interests, suggest that RRBs do not necessarily displace exploration and its possibilities for learning in autism.

Adaptive trajectories and early risk factors in the autism spectrum: A 15-year prospective study

Little is known about long-term outcomes. We investigate the adaptive trajectories and their risk factors in ASD. Data were obtained from 281 children prospectively followed untill adulthood. The final sample consisted of 106 individuals. Vineland scores were collected at baseline (T1), 3 (T2), 10 (T3), and 15 (T4) years later. A group-based method was used to identify homogeneous patterns of adaptive skills trajectories. Results show that among the children initially categorized as autistic, 82.6% remained over the ADOS diagnostic threshold, 11.9% converted to atypical autism, and 5.4% fell under the ADOS threshold. Most atypical autism diagnoses were unstable. Most (81.7%) autistic participants had an ID at inclusion. At T1, 59.3% were nonverbal, but only 39% at T4. Most changes occurred between 4 and 8 years of age. Approximately 25% of participants exhibited a "high" growth trajectory, in which progress continues throughout adolescence, and 75% a "low" growth trajectory, characterized by greater autistic symptoms, intellectual disability, and lower language abilities reflected by high CARS scores, low apparent DQ, and speech difficulties, which mostly, but not always, predicted low trajectories. Our findings suggest that the adaptive prognosis of autism is mostly poor in this cohort, biased toward intellectual disability. However, changes in diagnostic, speech, and adaptive status are not uncommon, even for indivduals with low measured intelligence or apparent intellectual disability, and are sometimes difficult to predict. Autism Research 2018, 11: 1455-1467. © 2018 International Society for Autism Research, Wiley Periodicals, Inc. LAY SUMMARY: Most autism diagnoses given before 5 years of age are stable to adulthood, but one-fifth of individuals are no longer considered to be autistic, even in a cohort biased toward apparent intellectual disability. Conversely, atypical autism diagnoses are mostly unstable. One-third of children who are nonverbal at 5 years are verbal within 15 years, mostly before 8 years of age. Concerning adaptive behavior outcomes, only one-fourth of children exhibit a high-growth trajectory through at least 15 years.

Gyrification changes are related to cognitive strengths in autism

Background

Behavioral, cognitive and functional particularities in autism differ according to autism subgroups and might be associated with domain-specific cognitive strengths. It is unknown whether structural changes support this specialization. We investigated the link between cortical folding, its maturation and cognitive strengths in autism subgroups presenting verbal or visuo-spatial peaks of abilities.

Methods

We measured gyrification, a structural index related to function, in 55 autistic participants with (AS-SOD, N = 27) or without (AS-NoSOD, N = 28) a speech onset delay (SOD) with similar symptom severity but respectively perceptual and verbal cognitive strengths, and 37 typical adolescents and young adults matched for intelligence and age. We calculated the local Gyrification Index (lGI) throughout an occipito-temporal region of interest and independently modeled age and peak of ability effects for each group.

Results

Unique gyrification features in both autistic groups were detected in localized clusters. When comparing the three groups, gyrification was found lower in AS-SOD in a fusiform visual area, whereas it was higher in AS-NoSOD in a temporal language-related region. These particular areas presented age-related gyrification differences reflecting contrasting local maturation pathways in AS. As expected, peaks of ability were found in a verbal subtest for the AS-NoSOD group and in the Block Design IQ subtest for the AS-SOD group.

Conclusions

Irrespective of their direction, regional gyrification differences in visual and language processing areas respectively reflect AS-SOD perceptual and AS-NoSOD language-oriented peaks. Unique regional maturation trajectories in the autistic brain may underline specific cognitive strengths, which are key variables for understanding heterogeneity in autism.

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Subgrouping the autism spectrum (AS) partly accounts for its heterogeneity.

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AS individuals with a speech onset delay (SOD) show perceptual cognitive strengths.

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AS individuals without a SOD show language-related cognitive strengths.

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AS subgroups show unique gyrification patterns in areas related to their strengths.

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Cortical structural maturation may be related to domain-specific strengths in AS.

Increase in Psychoactive Drug Prescriptions in the Years Following Autism Spectrum Diagnosis: A Population-Based Cohort Study

BACKGROUND

Psychoactive medications are commonly prescribed to autistic individuals, but little is known about how their use changes after diagnosis.

OBJECTIVES

This study describes the use of psychoactive drugs in children and young adults newly diagnosed with autism spectrum, between the year before and up to 5 years after diagnosis.

METHODS

Multivariable logistic regression was used to examine the relationship between the use psychoactive drugs before the first diagnosis of autism spectrum condition (from 1998 to 2010), and the clinical and demographic characteristics, identified from public health care databases in Quebec. The types of drugs prescribed and psychoactive polypharmacy were evaluated over 5 years of follow-up. Generalized estimating equations (GEE) were used to examine the association of age and time with the use of psychoactive drugs.

RESULTS

In our cohort of 2,989 individuals, diagnosis of another psychiatric disorder before autism spectrum strongly predicted psychoactive drug use. We observed that the proportion of users of psychoactive drugs increased from 35.6% the year before, to 53.2% 5 years after the autism spectrum diagnosis. Psychoactive polypharmacy (≥2 psychoactive drug classes) also increased from 9% to 22% in that time. Age and time since diagnosis strongly associated with the types and combinations of psychoactive drugs prescribed.

CONCLUSIONS

Psychoactive drug use and polypharmacy increases substantially over time after autism spectrum disorder diagnosis in children.

Typical versus delayed speech onset influences verbal reporting of autistic interests

BACKGROUND

The distinction between autism and Asperger syndrome has been abandoned in the DSM-5. However, this clinical categorization largely overlaps with the presence or absence of a speech onset delay which is associated with clinical, cognitive, and neural differences. It is unknown whether these different speech development pathways and associated cognitive differences are involved in the heterogeneity of the restricted interests that characterize autistic adults.

METHOD

This study tested the hypothesis that speech onset delay, or conversely, early mastery of speech, orients the nature and verbal reporting of adult autistic interests. The occurrence of a priori defined descriptors for perceptual and thematic dimensions were determined, as well as the perceived function and benefits, in the response of autistic people to a semi-structured interview on their intense interests. The number of words, grammatical categories, and proportion of perceptual/thematic descriptors were computed and compared between groups by variance analyses. The participants comprised 40 autistic adults grouped according to the presence (N = 20) or absence (N = 20) of speech onset delay, as well as 20 non-autistic adults, also with intense interests, matched for non-verbal intelligence using Raven's Progressive Matrices.

RESULTS

The overall nature, function, and benefit of intense interests were similar across autistic subgroups, and between autistic and non-autistic groups. However, autistic participants with a history of speech onset delay used more perceptual than thematic descriptors when talking about their interests, whereas the opposite was true for autistic individuals without speech onset delay. This finding remained significant after controlling for linguistic differences observed between the two groups.

CONCLUSIONS

Verbal reporting, but not the nature or positive function, of intense interests differed between adult autistic individuals depending on their speech acquisition history: oral reporting of intense interests was characterized by perceptual dominance for autistic individuals with delayed speech onset and thematic dominance for those without. This may contribute to the heterogeneous presentation observed among autistic adults of normal intelligence.

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.

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

Auditory Stream Segregation in Autism Spectrum Disorder: Benefits and Downsides of Superior Perceptual Processes

Auditory stream segregation allows us to organize our sound environment, by focusing on specific information and ignoring what is unimportant. One previous study reported difficulty in stream segregation ability in children with Asperger syndrome. In order to investigate this question further, we used an interleaved melody recognition task with children in the autism spectrum disorder (ASD). In this task, a probe melody is followed by a mixed sequence, made up of a target melody interleaved with a distractor melody. These two melodies have either the same [0 semitone (ST)] or a different mean frequency (6, 12 or 24 ST separation conditions). Children have to identify if the probe melody is present in the mixed sequence. Children with ASD performed better than typical children when melodies were completely embedded. Conversely, they were impaired in the ST separation conditions. Our results confirm the difficulty of children with ASD in using a frequency cue to organize auditory perceptual information. However, superior performance in the completely embedded condition may result from superior perceptual processes in autism. We propose that this atypical pattern of results might reflect the expression of a single cognitive feature in autism.