Beyond autism: a baby siblings research consortium study of high-risk children at three years of age

Rates of family history of autism and ADHD varies with recruitment approach and socio-economic status

Family history (FH) of autism and ADHD is not often considered during the recruitment process of developmental studies, despite high recurrence rates. We looked at the rate of autism or ADHD amongst family members of young children (9 to 46 months) in three UK-based samples (N = 1055) recruited using different methods. The rate of FH-autism or FH-ADHD was 3%-9% for diagnosed cases. The rate was highest in the sample recruited through an online participant pool, which also consisted of the most socio-economically diverse families. Lower parental education and family income were associated with higher rates of FH-ADHD and lower parental education with increased FH-autism. Thus, recruitment strategies have a meaningful impact on neurodiversity and the conclusions and generalizations that can be drawn. Specifically, recruitment using crowdsourcing websites could create a sample that is more representative of the wider population, compared to those recruited through university-related volunteer databases and social media.

Neural correlates of response to joint attention in 2-to-5-year-olds in relation to ASD and social-communicative abilities: An fNIRS and behavioral study

Autism spectrum disorder (ASD) is associated with life-long challenges with social cognition, and one of its earliest and most common manifestations is atypical joint attention, which is a pivotal skill in social-cognitive and linguistic development. Early interventions for ASD children often focus on training initiation of joint attention (IJA) and response to joint attention bids (RJA), which are important for social communication and cognition. Here, we used functional near-infrared spectroscopy and behavioral measures to test typically developing (TD, n = 17) and ASD children (n = 18), to address the relationship between the neural correlates of RJA and social-communicative behavior. Group-level differences were present for RJA-specific activation over right temporal sites, where TD children showed higher levels of activation during RJA than ASD children, whereas the two groups did not differ in the control condition. Correlations between neural activation and behavioral traits suggest that, in ASD children, neural activation during RJA is related to the frequency of RJA behavior when the former is measured over left temporal sites, and to social affect symptoms when considered for right temporal sites. Possible implications of the evidenced correlations are discussed.

Investigating Parental Observations of Early Autism Development in Simplex and Multiplex Families

Past research has highlighted the importance of early identification of developmental differences to improve targeted access to early interventions or supports. As such, it is of particular importance in the context of children at elevated likelihood of autism (such as where an older sibling has a diagnosis of autism), to better understand when and which early concerns are important as predictors of which children will benefit from pre-diagnostic supports. This study explored the number and frequency of retrospective parent reported concerns within the first year of life for children diagnosed with autism, both those who had an older sibling diagnosed with autism and those who did not, as well as for undiagnosed siblings. We found that at both 0-6 and 7-12 months, the only factor related to the presence or absence of early parent reported concerns was child diagnostic status, with the presence of reported early concerns more likely for children with a diagnosis of autism. These findings suggest that for children at elevated likelihood of autism, parents' concerns are driven primarily by developmental differences, with child's birth order and sibling diagnostic status not impacting on parent early concerns.

The Role of Gesture in Language Development for Neurotypical Children and Children With or at Increased Likelihood of Autism

For young children, gesture is found to precede and predict language development. However, we are still building a knowledge base about the specific nature of the relationship between gesture and speech. While much of the research on this topic has been conducted with neurotypical children, there is a growing body of work with children who have or are at increased likelihood of autism spectrum disorder (ASD). Here, we summarize the literature on relations between gesture and speech, including the role of child gesture production as well as that of gesture exposure (caregiver gesture). We include literature on both neurotypical children and children with or at likelihood of ASD, highlight the similarities and differences across populations, and offer implications for research as well as early identification and intervention.

Reduced covariation between brain morphometry and local spontaneous activity in young children with ASD

While disruptions in brain maturation in the first years of life in ASD are well documented, little is known about how the brain structure and function are related in young children with ASD compared to typically developing peers. We applied a multivariate pattern analysis to examine the covariation patterns between brain morphometry and local brain spontaneous activity in 38 toddlers and preschoolers with ASD and 31 typically developing children using T1-weighted structural MRI and resting-state fMRI data acquired during natural sleep. The results revealed significantly reduced brain structure-function correlations in ASD. The resultant brain structure and function composite indices were associated with age among typically developing children, but not among those with ASD, suggesting mistiming of typical brain maturational trajectories early in life in autism. Additionally, the brain function composite indices were associated with the overall developmental and adaptive behavior skills in the ASD group, highlighting the neurodevelopmental significance of early local brain activity in autism.

Early Motor Delays During the First 2 Years of Life in Autism Spectrum Disorder: A Scoping Review

PURPOSE

To summarize and appraise the emerging evidence on early motor skills of infants later diagnosed with autism spectrum disorder (ASD), and the association of early motor delays to later ASD diagnosis/characteristics.

METHODS

A literature search was conducted for studies published from 2000 to 2023 on the motor skills of infants later diagnosed with ASD, followed by screening and data extraction.

RESULTS

Current evidence suggested presence of early motor deficits including poor anticipatory movements, postural control, and gross/fine motor skills during the first 2 years of ASD. However, there was variability among studies with regard to study sample and methodology.

CONCLUSION

Although motor deficits are evident in infants, it is unclear whether these are specific to ASD or a consequence of general developmental disorder. Future research is needed on the investigation of specificity and severity of early motor delays, which can potentially assist in early identification of ASD.

The Stability and Validity of Automated Indices of Vocal Development in Infants With Autistic and Non-Autistic Siblings

PURPOSE

This study evaluates the extent to which automated indices of vocal development are stable and valid for predicting language in infants at increased familial likelihood for autism and/or language impairment and relatively lower likelihood infants.

METHOD

A group of infants with autistic siblings (Sibs-autism; 20 infants) and a comparison group of infants with non-autistic siblings (Sibs-NA; 20 infants) wore Language ENvironment Analysis (LENA) recording devices for 16 hr on 2 days within a 1-week period. Extant software was used to derive several putative indices of vocal development from these recordings. Stability of these variables was examined across and within groups. Expressive and receptive language aggregates were calculated for each participant. Multiple regression analyses were used to (a) evaluate zero-order correlations for variables derived from LENA recordings with concurrent and future language and (b) test whether those associations were moderated by group status.

RESULTS

Both stability and validity differed by variable and group status. All variables reached acceptable stability in the Sibs-autism group within two to three observations, whereas stability of most variables was attenuated in the Sibs-NA group. No variables were associated with concurrent language in the theoretically motivated direction across groups, but two variables were strongly associated with concurrent expressive language in only the Sibs-NA group. Additionally, two variables were associated with later expressive language, though these correlations were again stronger in the Sibs-NA versus Sibs-autism group.

CONCLUSIONS

Although selected automated indices of vocal development were stable in Sibs-autism and/or valid for predicting expressive language within Sibs-NA, no scores showed strong, theoretically motivated associations with language within the Sibs-autism group. Automated indices of vocal development may, thus, have limited validity or clinical utility for predicting language development in infants at elevated familial likelihood for autism.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.24415735.

Three year outcomes in infants with a family history of autism and/or attention deficit hyperactivity disorder

Background

Most research on early outcomes in infants with a family history (FH) of autism has focussed on categorically defined autism, although some have language and developmental delays. Less is known about outcomes in infants with a FH of attention deficit hyperactivity disorder (ADHD).

Methods

Infants with and without a FH of autism and/or ADHD, due to a first-degree relative with either or both conditions, were recruited at 5 or 10 months. Three year outcomes were characterised using latent profile analysis (LPA) across measures of cognitive ability, adaptive functioning and autism, ADHD and anxiety traits (n = 131). We additionally ran an LPA using only autism and ADHD measures, and the broader LPA in an independent cohort (n = 139) and in both cohorts combined (n = 270).

Results

A Low Developmental Level + High Behavioural Concerns class had elevated autism, ADHD and anxiety scores, low cognitive and adaptive function, and included all but one child with autism. A Low Developmental Level + Typical Behaviour class had average cognitive ability and typical behaviour but low adaptive function. A Typical Developmental Level + Some Behavioural Concerns class had average cognitive and adaptive function but slightly elevated behaviour scores. A High Developmental Level + Typical Behaviour class had above average cognitive ability and typical behaviour. All four LPAs identified classes characterised by combinations of either, or both, Low Development Level and elevated behaviour scores, as well as a typically developing class. No classes had elevated autism or ADHD traits in isolation.

Conclusions

Some infants with a FH of autism or ADHD have atypical developmental and behavioural outcomes, but do not show strong autism or ADHD traits in isolation. The field needs to recalibrate aims and methods to embrace the broader transdiagnostic pattern of outcomes seen in these infants.

Infant embodied attention in context: Feasibility of home-based head-mounted eye tracking in early infancy

Social communication emerges from dynamic, embodied social interactions during which infants coordinate attention to caregivers and objects. Yet many studies of infant attention are constrained to a laboratory setting, neglecting how attention is nested within social contexts where caregivers dynamically scaffold infant behavior in real time. This study evaluates the feasibility and acceptability of the novel use of head-mounted eye tracking (HMET) in the home with N = 40 infants aged 4 and 8 months who are typically developing and at an elevated genetic liability for autism spectrum disorder (ASD). Results suggest that HMET with young infants with limited independent motor abilities and at an elevated likelihood for atypical development is highly feasible and deemed acceptable by caregivers. Feasibility and acceptability did not differ by age or ASD likelihood. Data quality was also acceptable, albeit with younger infants showing slightly lower accuracy, allowing for preliminary analysis of developmental trends in infant gaze behavior. This study provides new evidence for the feasibility of using in-home HMET with young infants during a critical developmental period when more complex interactions with the environment and social partners are emerging. Future research can apply this technology to illuminate atypical developmental trajectories of embodied social attention in infancy.

Endophenotyping social cognition in the broader autism phenotype

Relatives of individuals with autism spectrum disorder (ASD) may display milder social traits of the broader autism phenotype (BAP) providing potential endophenotypic markers of genetic risk for ASD. We performed a case-control comparison to quantify social cognition and pragmatic language difficulties in the BAP (n = 25 cases; n = 33 controls) using the Faux Pas test (FPT) and the Goldman-Eisler Cartoon task. Using deep phenotyping we then examined patterns of inheritance of social cognition in two large multiplex families and the spectrum of performance in 32 additional families (159 members; n = 51 ASD, n = 87 BAP, n = 21 unaffected). BAP individuals showed significantly poorer FPT performance and reduced verbal fluency with the absence of a compression effect in social discourse compared to controls. In multiplex families, we observed reduced FPT performance in 89% of autistic family members, 63% of BAP relatives and 50% of unaffected relatives. Across all affected families, there was a graded spectrum of difficulties, with ASD individuals showing the most severe FPT difficulties, followed by the BAP and unaffected relatives compared to community controls. We conclude that relatives of probands show an inherited pattern of graded difficulties in social cognition with atypical faux pas detection in social discourse providing a novel candidate endophenotype for ASD.

EEG functional connectivity in infants at elevated familial likelihood for autism spectrum disorder

BACKGROUND

Many studies have reported that autism spectrum disorder (ASD) is associated with atypical structural and functional connectivity. However, we know relatively little about the development of these differences in infancy.

METHODS

We used a high-density electroencephalogram (EEG) dataset pooled from two independent infant sibling cohorts, to characterize such neurodevelopmental deviations during the first years of life. EEG was recorded at 6 and 12 months of age in infants at typical (N = 92) or elevated likelihood for ASD (N = 90), determined by the presence of an older sibling with ASD. We computed the functional connectivity between cortical sources of EEG during video watching using the corrected imaginary part of phase-locking values.

RESULTS

Our main analysis found no significant association between functional connectivity and ASD, showing only significant effects for age, sex, age-sex interaction, and site. Given these null results, we performed an exploratory analysis and observed, at 12 months, a negative correlation between functional connectivity and ADOS calibrated severity scores for restrictive and repetitive behaviors (RRB).

LIMITATIONS

The small sample of ASD participants inherent to sibling studies limits diagnostic group comparisons. Also, results from our secondary exploratory analysis should be considered only as potential relationships to further explore, given their increased vulnerability to false positives.

CONCLUSIONS

These results are inconclusive concerning an association between EEG functional connectivity and ASD in infancy. Exploratory analyses provided preliminary support for a relationship between RRB and functional connectivity specifically, but these preliminary observations need corroboration on larger samples.

An Examination of Family Transmission of Traits Measured by the Social Responsiveness Scale-Short Form

PURPOSE

The Social Responsiveness Scale (SRS) is frequently used in research settings to measure characteristics associated with autism spectrum disorders (ASD). A short version has been developed but not yet tested for certain properties of the full SRS, such as familiality. The purpose of this study was to determine if prior familiality findings for the full SRS can be replicated using the short form by measuring the associations of the parental Social Responsiveness Scale-Short Form (SRS-SF) scores with child ASD diagnoses and child SRS-SF scores.

METHODS

We used a nested case-control study within a longitudinal cohort study design. Participants were selected from the Nurses' Health Study II (NHS II). Cases were children of study participants who had been diagnosed with ASD, while controls had not been diagnosed with ASD and were frequency matched by year of birth to cases. 2144 out of 3161 eligible participants returned SRS forms for a child and at least one parent. Participants in NHS II completed SRS forms for their spouses and spouses completed SRS forms for NHS II participants. Parental SRS-SF scores were based on a subset of 16 questions from the SRS. ASD diagnosis among children was reported by the mothers and validated in a subset using the Autism Diagnostic Interview-Revised, as well as child SRS-SF scores.

RESULTS

Children whose parents both had elevated SRS-SF scores (those in the top 20% of the study distribution) had a higher odds of ASD diagnosis than those who did not have elevated parental scores (OR 2.25; 95% CI 1.41, 3.58). Additionally, children whose fathers had elevated SRS-SF scores had a higher odds of ASD diagnosis (OR 2.18; 95% CI 1.60, 2.97) than those whose fathers scores were not elevated. In sex-stratified analyses, male children with elevated parental SRS-SF scores had a higher odds of ASD diagnosis than those who did not have elevated parental scores. These associations were not as evident among female children. Parental SRS-SF scores also predicted child SRS-SF scores among controls.

CONCLUSION

These findings are similar to prior findings for the full SRS and support the ability of the SRS-SF to capture familiality of ASD-related traits.

Neural mechanisms of language development in infancy

Understanding the neural processes underpinning individual differences in early language development is of increasing interest, as it is known to vary in typical development and to be quite heterogeneous in neurodevelopmental conditions. However, few studies to date have tested whether early brain measures are indicative of the developmental trajectory of language, as opposed to language outcomes at specific ages. We combined recordings from two longitudinal studies, including typically developing infants without a family history of autism, and infants with increased likelihood of developing autism (infant-siblings) (N = 191). Electroencephalograms (EEG) were recorded at 6 months, and behavioral assessments at 6, 12, 18, 24 and 36 months of age. Using a growth curve model, we tested whether absolute EEG spectral power at 6 months was associated with concurrent language abilities, and developmental change in language between 6 and 36 months. We found evidence of an association between 6-month alpha-band power and concurrent, but not developmental change in, expressive language ability in both infant-siblings and control infants. The observed association between 6-month alpha-band power and 6-month expressive language was not moderated by group status, suggesting some continuity in neural mechanisms.

Mapping the Physical Language of Children Diagnosed with Autism: A Preliminary Study

Children diagnosed with autism spectrum disorder have a unique motor profile, characterized by, for example, unusual posture or compulsive use of the body. However, not much is known about specific characteristics of their physical language, such as their movement direction, their self-touch pattern, etc., and even less is known about these characteristics with regard to their typically developing siblings. In this first of its kind study, we attempted to map the physical language of children diagnosed with autism spectrum disorder and to compare it to their typically developing siblings. To this end, we recruited 12 pairs of siblings, comprising one sibling with a diagnosis of autism and one sibling who is typically developing. The siblings were asked to play for 10 min and were videotaped throughout the interaction. We evaluated the siblings' physical language using Laban's movement analysis. We found significant and substantial differences between the physical language of the children diagnosed with autism and their typically developing siblings. The results are discussed in terms of the implications of the differences in physical language between the two populations and how movement analysis could be important for interventions in order to improve the communication and social abilities of ASD children.

Associations between attentional biases to fearful faces and social-emotional development in infants with and without an older sibling with autism

During the first year of life, infants become increasingly attuned to facial emotion, with heightened sensitivity to faces conveying threat observed by age seven months as illustrated through attentional biases (e.g., slower shifting away from fearful faces). Individual differences in these cognitive attentional biases have been discussed in relation to broader social-emotional functioning, and the current study examines these associations in infants with an older sibling with autism spectrum disorder (ASD), a group with an elevated likelihood of a subsequent ASD diagnosis (ELA; n = 33), and a group of infants with no family history of ASD who are at low likelihood of ASD (LLA; n = 24). All infants completed a task measuring disengagement of attention from faces at 12 months (fearful, happy, neutral), and caregivers completed the Infant-Toddler Social and Emotional Assessment at 12, 18, and/or 24 months. For the full sample, greater fear bias in attention disengagement at 12 months related to more internalizing behaviors at 18 months, and this was driven by the LLA infants. When examining groups separately, findings revealed that LLA with a greater fear bias had more difficult behaviors at 12, 18, and 24 months; in contrast, ELA showed the opposite pattern, and this was most pronounced for ELA who later received an ASD diagnosis. These preliminary group-level findings suggest that heightened sensitivity to fearful faces might serve an adaptive function in children who later receive an ASD diagnosis, but in infants with no family history of ASD, increased biases might reflect a marker of social-emotional difficulties.

Sex Differences in the Developmental Trajectories of Autism Spectrum Disorder

Purpose of Review

Females and males are disproportionately diagnosed with autism, a sex difference that has historically represented this neurodevelopmental condition. The current review examines lifespan developmental trajectories of autism based on sex to elucidate behavioral phenotypic differences that may contribute to differential rates of diagnosis.

Recent Findings

We review sex differences in diagnostic criteria: social communication and restricted interests/repetitive behaviors (RRBs). Results suggest RRBs are more indicative of a diagnosis in males, whereas social differences are more indicative of a diagnosis in females. Factors contributing to a later diagnosis in females include social strengths (camouflaging) and diagnostic overshadowing.

Summary

Sex differences in diagnostic criteria may contribute to differential rates of identification in males and females. Sex differences are most pronounced when assessing naturalistic social communication instead of reliance on standardized measure. Numerous future directions are identified including increasing samples of sub-threshold autistic females and evaluating longitudinal sex differences.

Advancing research on early autism through an integrated risk and resilience perspective

To date, a deficit-oriented approach dominates autism spectrum disorder (ASD) research, including studies of infant siblings of children with ASD at high risk (HR) for the disabilities associated with this disorder. Despite scientific advances regarding early ASD-related risk, there remains little systematic investigation of positive development, limiting the scope of research and quite possibly a deeper understanding of pathways toward and away from ASD-related impairments. In this paper, we argue that integrating a resilience framework into early ASD research has the potential to enhance knowledge on prodromal course, phenotypic heterogeneity, and developmental processes of risk and adaptation. We delineate a developmental systems resilience framework with particular reference to HR infants. To illustrate the utility of a resilience perspective, we consider the "female protective effect" and other evidence of adaptation in the face of ASD-related risk. We suggest that a resilience framework invites focal questions about the nature, timing, levels, interactions, and mechanisms by which positive adaptation occurs in relation to risk and developmental pathways toward and away from ASD-related difficulties. We conclude with recommendations for future research, including more focus on adaptive development and multisystem processes, pathways away from disorder, and reconsideration of extant evidence within an integrated risk-and-resilience framework.

Associations Between Caregiver Stress and Language Outcomes in Infants With Autistic and Non-Autistic Siblings: An Exploratory Study

PURPOSE

Caregivers of autistic children present with high stress levels, which have been associated with poorer child outcomes in several domains, including language development. However, prior to this study, it was unknown whether elevated caregiver stress was associated with language development in infant siblings of autistic children (Sibs-autism), who are at increased likelihood of receiving a future diagnosis of autism and/or language impairment compared to infant siblings of non-autistic children. This study explored the degree to which, as well as the mechanisms by which, caregiver stress was linked with later language outcomes of Sibs-autism and infant siblings of non-autistic children (Sibs-NA).

METHOD

Participants were 50 infants (28 Sibs-autism; 22 Sibs-NA) aged 12-18 months at the first time point in this study (Time 1). Infants were seen again 9 months later, at 21-27 months of age (Time 2). Caregiver stress was measured via a validated self-report measure at Time 1. Caregiver language input, the putative mechanism by which caregiver stress may influence later language outcomes, was collected via two daylong recordings from digital recording (Language ENvironment Analysis) devices worn by the child at this same time point. Child language outcomes were measured via standardized and caregiver report measures at Time 2.

RESULTS

Several models testing hypothesized indirect effects of caregiver stress on later child language outcomes through caregiver language input were statistically significant. Specifically, significant indirect effects suggest that (a) caregivers with increased stress tend to speak less to their infants, and (b) this reduced language input tends to covary with reduced child language outcomes later in life for Sibs-autism and Sibs-NA.

CONCLUSIONS

This study provides new insights into links between caregiver stress, caregiver language input, and language outcomes in Sibs-autism and Sibs-NA. Further work is necessary to understand how to best support caregivers and optimize the language learning environments for infants.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.21714368.

Linguistic and motor profiles in preschool and school-age children with an older sibling with autism spectrum disorder

This study examines receptive-expressive language, gross-fine motor skills, and IQ abilities in 78 children, 43 children with an older sibling with autism spectrum disorder (Sibs-ASD) and 35 children with an older sibling with typical development, ranging from 4 to 11 years of age. Depending on age, both groups were divided in preschool and school groups. The results show that more than 76% of Sibs-ASD performed at least one language and/or motor skill under 25th percentile. Significant differences were described at preschool stage in three aspects: grammatical comprehension, ball skills, and global motor skills. At school age, significant differences were found in two aspects: expressive language, and ball skills. Some differences seem to decrease over time; meanwhile others seem to increase; and others remain stable. Thus, it seems that vulnerability continues in unaffected Sibs-ASD and suggest that this population may benefit from continued screening and monitoring into the preschool and school-age stages.

A prospective study of associations between early fearfulness and perceptual sensitivity and later restricted and repetitive behaviours in infants with typical and elevated likelihood of autism

LAY ABSTRACT

Restricted interests and repetitive behaviours are central to the diagnosis of autism and can have profound effects on daily activities and quality of life. These challenges are also linked to other co-occurring conditions such as anxiety and sensory sensitivities. Here, we looked at whether early emerging signs of anxiety and sensory problems appear before symptoms of autism by studying infants with a family history of autism, as these infants are more likely to develop autism themselves. Studying infant siblings provides an opportunity for researchers to focus on early developmental markers of autism as these infants can be followed from birth. This study found that early infant signs of anxiety (e.g. fear/shyness) predicted later perceptual sensitivity, and those infants who scored higher on fear/shyness and sensitivity were more likely to experience more persistent repetitive behaviours, but also social and communication difficulties in toddlerhood. Early signs of anxiety and perceptual sensitivity may thus relate to both later social difficulties and repetitive behaviours. These findings support the importance of further research exploring the causal links between these domains in relation to autism, resulting in increased understanding of children who go onto develop autism in the future and guiding early interventions and supports.

High-Risk Siblings without Autism: Insights from a Clinical and Eye-Tracking Study

Joint attention (JA)-the human ability to coordinate our attention with that of other people-is impaired in the early stage of Autism Spectrum Disorder (ASD). However, little is known about the JA skills in the younger siblings of children with ASD who do not develop ASD at 36 months of age [high-risk (HR)-noASD]. In order to advance our understanding of this topic, a prospective multicenter observational study was conducted with three groups of toddlers (age range: 18-33 months): 17 with ASD, 19 with HR-noASD and 16 with typical development (TD). All subjects underwent a comprehensive clinical assessment and an eye-tracking experiment with pre-recorded stimuli in which the visual patterns during two tasks eliciting initiating joint attention (IJA) were measured. Specifically, fixations, transitions and alternating gaze were analyzed. Clinical evaluation revealed that HR-noASD subjects had lower non-verbal cognitive skills than TD children, while similar levels of restricted and repetitive behaviors and better social communication skills were detected in comparison with ASD children. Eye-tracking paradigms indicated that HR-noASD toddlers had visual patterns resembling TD in terms of target-object-to-face gaze alternations, while their looking behaviors were similar to ASD toddlers regarding not-target-object-to-face gaze alternations. This study indicated that high-risk, unaffected siblings displayed a shared profile of IJA-eye-tracking measures with both ASD patients and TD controls, providing new insights into the characterization of social attention in this group of toddlers.

Hypoconnectivity between anterior insula and amygdala associates with future vulnerabilities in social development in a neurodiverse sample of neonates

Altered resting state functional connectivity (FC) involving the anterior insula (aINS), a key node in the salience network, has been reported consistently in autism. Here we examined, for the first time, FC between the aINS and the whole brain in a sample of full-term, postmenstrual age (PMA) matched neonates (mean 44.0 weeks, SD = 1.5) who due to family history have high likelihood (HL) for developing autism (n = 12) and in controls (n = 41) without family history of autism (low likelihood, LL). Behaviors associated with autism were evaluated between 12 and 18 months (M = 17.3 months, SD = 2.5) in a subsample (25/53) of participants using the First Year Inventory (FYI). Compared to LL controls, HL neonates showed hypoconnectivity between left aINS and left amygdala. Lower connectivity between the two nodes was associated with higher FYI risk scores in the social domain (r(25) = -0.561, p = .003) and this association remained robust when maternal mental health factors were considered. Considering that a subsample of LL participants (n = 14/41) underwent brain imaging during the fetal period at PMA 31 and 34 weeks, in an exploratory analysis, we evaluated prospectively development of the LaINS-Lamy connectivity and found that the two areas strongly coactivate throughout the third trimester of pregnancy. The study identifies left lateralized anterior insula-amygdala connectivity as a potential target of further investigation into neural circuitry that enhances likelihood of future onset of social behaviors associated with autism during neonatal and potentially prenatal periods.

The Clinical Implications of the Academic Performance of the Siblings of Individuals With Autism Spectrum Disorder

We all know that autism spectrum disorder (ASD) can affect academic performance. Many children with autism face different challenges at school. However, less attention is paid to the siblings of autistic children, who are at a high risk of ASD or the broad autism phenotype (BAP). Recent data also shows that many siblings of ASD children suffer from neurodevelopmental disorders, mental health problems as well as poor academic performance. This review will look at the possible etiologies of the poor school performance of autistic children's siblings, with an emphasis on the challenges they face. We will also highlight the clinical implications of these findings, and the possible solutions that can help this vulnerable group.

Sibling Influences on Trajectories of Maladaptive Behaviors in Autism

Siblings play an important role in the behavioral trajectories of individuals with autism spectrum disorder (ASD). While having siblings has been associated with positive outcomes in ASD, including stronger adaptive functioning, social and non-verbal communication, and theory of mind, little is known about the impact of siblings on more negative outcomes, such as maladaptive behaviors. To address this gap, the present longitudinal study tested sibling predictors of trajectories of maladaptive behaviors (e.g., teacher- and parent-reported hyperactivity, irritability, and social withdrawal) from childhood through early adulthood among individuals with ASD and non-spectrum delays. Multilevel models revealed that, while the mere presence of a sibling did not impact maladaptive behavior trajectories apart from teacher-reported hyperactivity, the diagnostic profile of the sibling (e.g., emotional/behavioral disorder, ASD, medical condition) emerged as an important predictor. Specifically, although findings varied across teacher and parent reports, more hyperactivity and irritability across time was identified when the sibling had diagnoses of an emotional/behavioral disorder, ASD, and/or a medical condition. Overall, this study provides novel insight into the broader family-level factors that influence the presentation of maladaptive behaviors across time and across contexts.

Profiles and correlates of language and social communication differences among young autistic children

Delays in early language development are characteristic of young autistic children, and one of the most recognizable first concerns that motivate parents to seek a diagnostic evaluation for their child. Although early language abilities are one of the strongest predictors of long-term outcomes, there is still much to be understood about the role of language impairment in the heterogeneous phenotypic presentation of autism. Using a person-centered, Latent Profile Analysis, we first aimed to identify distinct patterns of language and social communication ability in a clinic-based sample of 498 autistic children, ranging in age from 18 to 60 months (M = 33 mo, SD = 12 mo). Next, a multinomial logistic regression analysis was implemented to examine sociodemographic and child-based developmental differences among the identified language and social communication profiles. Three clinically meaningful profiles were identified from parent-rated and clinician-administered measures: Profile 1 (48% of the sample) “Relatively Low Language and Social Communication Abilities,” Profile 2 (34% of the sample) “Relatively Elevated Language and Social Communication Abilities,” and Profile 3 (18% of the sample) “Informant Discrepant Language and Relatively Elevated Social Communication Abilities.” Overall, young autistic children from the lowest-resource households exhibited the lowest language and social communication abilities, and the lowest non-verbal problem-solving and fine-motor skills, along with more features of attention-deficit/hyperactivity disorder and atypical auditory processing. These findings highlight the need for effective community-based implementation strategies for young autistic children from low-resource households and underrepresented communities to improve access to individualized quality care.

Cortical Source Analysis of the Face Sensitive N290 ERP Component in Infants at High Risk for Autism

Appropriate head models for cortical source analysis were investigated and applied to source analyses examining the neural bases of the face-sensitive N290 event-related potential (ERP) component in infants at high risk for autism spectrum disorder (ASD). This included infant siblings of children with ASD (ASIBs) and infants with fragile X syndrome (FXS). First, alternative head models for use with ASIBs and FXS were investigated. Head models created from the infant's own MRI were examined in relation to five head models based on average MRI templates. The results of the head model comparison identified group-specific (i.e., ASIB or FXS) head models created from a large collection of structural MRIs as the best substitution for the head model created from the participant's own structural MRI. Second, the cortical source analysis was completed on N290 data collected from a previous study to investigate brain areas associated with face sensitive ERP responses. Participants' own MRIs were used for head models when available, and the group-specific head model was used when the participants' own MRIs were not available. The results provide evidence for unique patterns of neural activation during face processing across infants at high and low risk for ASD and across etiologically distinct high-risk groups. All infants demonstrated greater activation to faces than toys in brain areas most associated with specialized face processing. Infants with FXS displayed higher levels of activation to faces across all areas analyzed, while ASIBs show more muted levels of activation. Overall, the results of the current study demonstrate the importance of group-specific head models for accurate cortical source analysis in infants at high risk for ASD. This also allows for further research on early distinctions in brain function based on risk status.

Neuronal gating of tactile input and sleep in 10-month-old infants at typical and elevated likelihood for autism spectrum disorder

Sleep problems in Autism Spectrum Disorder (ASD) emerge early in development, yet the origin remains unclear. Here, we characterise developmental trajectories in sleep onset latency (SOL) and night awakenings in infants at elevated likelihood (EL) for ASD (who have an older sibling with ASD) and infants at typical likelihood (TL) for ASD. Further, we test whether the ability to gate tactile input, using an EEG tactile suppression index (TSI), associates with variation in SOL and night awakenings. Parent-reported night awakenings and SOL from 124 infants (97 at EL for ASD) at 5, 10 and 14 months were analyzed using generalized estimating equations. Compared to TL infants, infants at EL had significantly more awakenings and longer SOL at 10 and 14 months. The TSI predicted SOL concurrently at 10 months, independent of ASD likelihood status, but not longitudinally at 14 months. The TSI did not predict night awakenings concurrently or longitudinally. These results imply that infants at EL for ASD wake up more frequently during the night and take longer to fall asleep from 10 months of age. At 10 months, sensory gating predicts SOL, but not night awakenings, suggesting sensory gating differentially affects neural mechanisms of sleep initiation and maintenance.

Early predictors of language skills at 3 years of age vary based on diagnostic outcome: A baby siblings research consortium study

While previous work has identified the early predictors of language skills in infants at elevated familial risk (ER) and low familial risk (LR) for autism spectrum disorder (ASD), no studies to date have explored whether these predictors vary based on diagnostic outcome of ASD or no ASD. The present study used a large, multisite dataset to examine associations between a set of commonly studied predictor variables (infant gesture abilities, fine motor skills, nonverbal cognition, and maternal education level), measured at 12 months, and language skills, measured at 3 years, across three diagnostic outcome groups-infants with ASD ("ASD"), ER infants without ASD ("ER-no ASD"), and LR infants without ASD ("LR-no ASD"). Findings revealed that the predictors of language skills differed across groups, as gesture abilities were positively associated with language skills in the ER-no ASD group but negatively associated with language skills in the ASD group. Furthermore, maternal education level was positively associated with language skills in the ASD and LR-no ASD groups only. Variability in these early predictors may help explain why language skills are heterogeneous across the autism spectrum, and, with further study, may help clinicians identify those in need of additional and/or specialized intervention services that support language development. LAY SUMMARY: The present study identified predictors of language skills in infants with and without autism spectrum disorder (ASD). Maternal education level and 12-month gesture abilities predicted 3-year language skills in infants with ASD. Measuring these predictors early in life may help identify infants and families in need of additional and/or specialized intervention services that support language development.

Patterns of objectively measured motor activity among infants developing ASD and concerns for ADHD

BACKGROUND

Heightened motor activity is a hallmark of attention-deficit/hyperactivity disorder (ADHD), yet high activity levels are also often reported in young children with autism spectrum disorder (ASD). It is currently unclear whether increased motor activity represents a distinct versus shared early predictor of ASD and ADHD; no prior studies have directly examined this prospectively. We investigated differences in longitudinal patterns of objectively measured motor activity during early development.

METHODS

Participants included 113 infants at high and low risk for ASD or ADHD. Continuous motion-based activity was recorded using tri-axial accelerometers at 12, 18, 24, and 36 months of age. At 36 months, participants were categorized into one of three outcome groups: ASD (n = 19), ADHD Concerns (n = 17), and Typically Developing (TD; n = 77). Group differences in trajectories of motor activity were examined in structured and semistructured contexts. Associations with behaviors relevant to ASD, ADHD, and general development were also examined.

RESULTS

In both structured and semistructured contexts, both the ASD and ADHD Concerns groups exhibited heightened activity relative to the TD group by 18 months; the ASD group exhibited higher activity than the ADHD Concerns group at 24-36 months in the structured context only. Attention/behavior regulation, nonverbal, and verbal development-but not social engagement-were differentially associated with objectively measured activity by outcome group across contexts.

CONCLUSIONS

Overactivity may be a shared, rather than distinct, precursor of atypical development in infants/toddlers developing ASD and concerns for ADHD, emerging as early as 18 months. Group differences in overactivity may be context-specific and associated with different underlying mechanisms.

Clinical and behavioral attributes leading to sleep disorders in children on the autism spectrum

Sleep disorders are a common comorbid condition in children diagnosed with autism spectrum disorder ("autism"). However, the relationship between the clinical features of autism and sleep disorders remains unclear. A better understanding of the inherent autism-related characteristics linked to comorbid sleep disorders would improve comprehensive assessment and management. This study examined the relationship between sociodemographics, autism symptoms, sleep problems, cognitive status, behavioral attributes, and sensory profiles. Using data from 1268 participants who took part in the Australian Autism Biobank, sleep-related measurements using the Child Sleep Habits Questionnaire (CSHQ) were compared between autistic children aged 2 to 17 (N = 969), their siblings (N = 188), and unrelated children without an autism diagnosis (N = 111). The known relationship between sleep problems and autism was further explored by including scores from the Autism Diagnostic Observation Schedule-2, Mullen Scales of Early Learning, Vineland Adaptive Behavioral Scale-II and the Short Sensory Profile-2; which were included in analyses for autistic participants who had a completed CSHQ. Multiple regression models were used to identify clinical/behavioral variables associated with CSHQ subscales. The autism group had a significantly higher total CSHQ score than the sibling and comparison groups (p < 0.001), indicating worse sleep quality. Within the autism group, lower adaptive behaviors (i.e., VABS-II) and sensory issues (i.e., SSP-2 subclass scores) were positively associated with the severity of sleep problems (i.e., the CSHQ subclass scores) (p < 0.001). The significant functional impact of poor sleep on autistic children warrants an assessment of sleep as a critical part of a holistic approach to supporting autistic children and their families. LAY SUMMARY: Autistic children generally have co-occurring conditions. Sleep disorders impact approximately 50%-80% of autistic children. The impact on the quality of life for both the children and their families can be significant. This study compares sleep problems in autistic children and adolescents with their siblings and children without a diagnosis of autism, and investigates the relationship between specific autistic traits, daily life behaviors and sleep problems. The findings highlight the importance of a holistic assessment for autistic children and matching appropriate sleep intervention and supports where indicated.

Looking for “fNIRS Signature” in Autism Spectrum: A Systematic Review Starting From Preschoolers

Accumulating evidence suggests that functional Near-Infrared Spectroscopy (fNIRS) can provide an essential bridge between our current understanding of neural circuit organization and cortical activity in the developing brain. Indeed, fNIRS allows studying brain functions through the measurement of neurovascular coupling that links neural activity to subsequent changes in cerebral blood flow and hemoglobin oxygenation levels. While the literature offers a multitude of fNIRS applications to typical development, only recently this tool has been extended to the study of neurodevelopmental disorders (NDDs). The exponential rise of scientific publications on this topic during the last years reflects the interest to identify a “fNIRS signature” as a biomarker of high translational value to support both early clinical diagnosis and treatment outcome. The purpose of this systematic review is to describe the updating clinical applications of fNIRS in NDDs, with a specific focus on preschool population. Starting from this rationale, a systematic search was conducted for relevant studies in different scientific databases (Pubmed, Scopus, and Web of Science) resulting in 13 published articles. In these studies, fNIRS was applied in individuals with Autism Spectrum Disorder (ASD) or infants at high risk of developing ASD. Both functional connectivity in resting-state conditions and task-evoked brain activation using multiple experimental paradigms were used in the selected investigations, suggesting that fNIRS might be considered a promising method for identifying early quantitative biomarkers in the autism field.

The amplitude of fNIRS hemodynamic response in the visual cortex unmasks autistic traits in typically developing children

Autistic traits represent a continuum dimension across the population, with autism spectrum disorder (ASD) being the extreme end of the distribution. Accumulating evidence shows that neuroanatomical and neurofunctional profiles described in relatives of ASD individuals reflect an intermediate neurobiological pattern between the clinical population and healthy controls. This suggests that quantitative measures detecting autistic traits in the general population represent potential candidates for the development of biomarkers identifying early pathophysiological processes associated with ASD. Functional near-infrared spectroscopy (fNIRS) has been extensively employed to investigate neural development and function. In contrast, the potential of fNIRS to define reliable biomarkers of brain activity has been barely explored. Features of non-invasiveness, portability, ease of administration, and low-operating costs make fNIRS a suitable instrument to assess brain function for differential diagnosis, follow-up, analysis of treatment outcomes, and personalized medicine in several neurological conditions. Here, we introduce a novel standardized procedure with high entertaining value to measure hemodynamic responses (HDR) in the occipital cortex of adult subjects and children. We found that the variability of evoked HDR correlates with the autistic traits of children, assessed by the Autism-Spectrum Quotient. Interestingly, HDR amplitude was especially linked to social and communication features, representing the core symptoms of ASD. These findings establish a quick and easy strategy for measuring visually-evoked cortical activity with fNIRS that optimize the compliance of young subjects, setting the background for testing the diagnostic value of fNIRS visual measurements in the ASD clinical population.

Mechanisms by which Early Eye Gaze to the Mouth During Multisensory Speech Influences Expressive Communication Development in Infant Siblings of Children with and without Autism

Looking to the mouth of a talker early in life predicts expressive communication. We hypothesized that looking at a talker's mouth may signal that infants are ready for increased supported joint engagement and that it subsequently facilitates prelinguistic vocal development and translates to broader gains in expressive communication. We tested this hypothesis in 50 infants aged 6-18 months with heightened and general population-level likelihood of autism diagnosis (Sibs-autism and Sibs-NA; respectively). We measured infants' gaze to a speaker's face using an eye tracking task, supported joint engagement during parent-child free play sessions, vocal complexity during a communication sample, and broader expressive communication. Looking at the mouth was indirectly associated with expressive communication via increased higher-order supported joint engagement and vocal complexity. This indirect effect did not vary according to sibling status. This study provides preliminary insights into the mechanisms by which looking at the mouth may influence expressive communication development.

Diagnostic Stability and Phenotypic Differences Among School-Age Children Diagnosed With ASD Before Age 2

Given the importance of early detection, it is critical to understand the non-linearity in manifestation of ASD before age 24 months, when ASD symptoms are beginning to consolidate, through the age of 36 months when stability of ASD diagnosis is reportedly high into school-age when increased demands may challenge previously successful compensatory processes and permit first ASD detection. We employed a prospective, longitudinal design focused on children with an older sibling with ASD (n = 210) who received diagnostic evaluations at mean ages of 15.4 months (Time 1), 36.6 months (Time 2), and 5.7 years (Time 3) to examine: (1) diagnostic stability, (2) developmental trajectories associated with different patterns of ASD vs. non-ASD classifications, and (3) predictors of classification group over time. Clinical best estimate (CBE) diagnosis of ASD or non-ASD was made at each time point. Linear mixed-effects models were implemented to examine differences in developmental trajectories of stable and dynamic diagnostic groups. Multinomial logistic regression analyses were used to examine predictors of the likelihood of belonging to each CBE diagnostic classification group. Results revealed that sensitivity and stability of an ASD diagnosis significantly increased from Time 1 (sensitivity: 52%; stability: 63%) to Time 2 (sensitivity: 86%; stability: 68%). Different developmental trajectories of autism symptom severity and non-verbal and verbal IQ were observed across groups, with differences first observed at Time 1 and becoming more pronounced through Time 3. Presence of restricted and repetitive behaviors as well as limitations in initiation of joint attention and expressive language skills differentially predicted the likelihood of belonging to the different CBE diagnostic classification groups. Results suggest that ASD symptoms may emerge or attenuate over time, with some children meeting diagnosis at follow-up, and other children no longer meeting diagnostic criteria. From a systems perspective, diagnostic non-linearity may be viewed as a dynamic developmental process, where emergent properties arising from various biological, genetic, and experiential factors interact, culminating in phenotypic phenomena that change over time. Clinical implications include extending universal ASD and social communication screening into school-age, supporting families' understanding of diagnostic shifts, and ensuring unbiased diagnostic decision-making when following children with ASD.

Neural Correlates of Infant Face Processing and Later Emerging Autism Symptoms in Fragile X Syndrome

Fragile X syndrome (FXS) is the leading known genetic cause of autism spectrum disorder (ASD) with 60-74% of males with FXS meeting diagnostic criteria for ASD. Infants with FXS have demonstrated atypical neural responses during face processing that are unique from both typically developing, low-risk infants and infants at high familial risk for ASD (i.e., infants siblings of children with ASD). In the current study, event-related potential (ERP) responses during face processing measured at 12 months of age were examined in relation to ASD symptoms measured at ~48 months of age in participants with FXS, as well as siblings of children with ASD and low-risk control participants. Results revealed that greater amplitude N290 responses in infancy were associated with more severe ASD symptoms in childhood in FXS and in siblings of children with ASD. This pattern of results was not observed for low-risk control participants. Reduced Nc amplitude was associated with more severe ASD symptoms in participants with FXS but was not observed in the other groups. This is the first study to examine ASD symptoms in childhood in relation to infant ERP responses in FXS. Results indicate that infant ERP responses may be predictive of later symptoms of ASD in FXS and the presence of both common and unique pathways to ASD in etiologically-distinct high-risk groups is supported (i.e., syndromic risk vs. familial risk).

Sibling Adjustment and Sibling Relationships Associated with Clusters of Needs in Children with Autism: A Novel Methodological Approach

We tested a novel methodological approach to examine associations between characteristics of autistic children and outcomes for siblings. Cluster analysis was used to define five groups of children with autism (n = 168) based on autism symptoms, adaptive behavior, pro-social behavior, and behavior problems. Primary and secondary parent carers, and siblings themselves, reported on sibling relationship quality and psychological adjustment. Siblings of autistic children with a mild symptom profile, high levels of adaptive skills, but high internalizing and externalizing problems had the highest level of these problems themselves and more conflict in their relationship. Siblings of autistic children with the most complex support needs (adaptive skills deficits, severe autism symptoms) reported lower warmth relationships but not elevated internalizing and externalizing problems.

Ethical dimensions of translational developmental neuroscience research in autism

BACKGROUND

Since the 1990s, increasing research has been devoted to the identification of biomarkers for autism to help attain more objective diagnosis; enable early prediction of prognosis; and guide individualized intervention options. Early studies focused on the identification of genetic variants associated with autism, but more recently, research has expanded to investigate neurodevelopmental markers. While ethicists have extensively discussed issues around advances in autism genomics, much less ethical scrutiny has focused on research on early neurodevelopment and on the interventions being developed as a result.

OBJECTIVES

We summarize the current state of the science on the identification of early markers for autism and its potential clinical applications, before providing an overview of the ethical issues arising from increasing understanding of children's neurodevelopment in very early life.

RESULTS

Advances in the understanding of brain and behavioral trajectories preceding later autism diagnosis raise ethical concerns around three themes: (a) New models for understanding autism; (b) Risks and benefits of early identification and intervention; and (c) Communication of early concerns to families. These ethical issues should be further investigated in research conducted in partnership with autistic people and their families.

CONCLUSIONS

This paper highlights the need for ethical scrutiny of early neurodevelopmental research in autism. Scrutiny requires expertise and methods from the basic sciences and bioethics, as well as constructive collaborations among autistic people, their parents, and autism researchers to anticipate early interventions that serve the community's interests and accommodate the varied experiences and preferences of people on the spectrum and their families.

Infant physiological activity and the early emergence of social communication

Early in life, social engagement is facilitated by effective regulation during times of rest and stress. Physiological regulation during social play and in response to sudden environmental changes or social stressors may play an important role in sustaining social engagement in infancy and facilitate the acquisition of early social-communication skills. The aim of this study was to investigate the role of physiological activity during social play, including respiratory sinus arrhythsmia (RSA) and heart rate-defined attention, in the early emergence of social-communication skills. Using RSA as an index of vagal tone, we measured vagal tone, vagal suppression, and heart rate-defined sustained attention during a social interaction with a caregiver (i.e., the Still-Face procedure) in 21 infants aged 3-4 months. At 9 months, caregivers reported on their infant's early social-communication skills. Results suggest that RSA, RSA suppression, and heart rate-defined sustained attention to a caregiver are significantly associated with early-emerging social-communication skills at 9 months. In addition, RSA and heart rate-defined sustained attention during social play were highly related. Suppression of RSA during the Still-Face phase of the infant-caregiver interaction emerged as a particularly strong predictor of later-developing social-communication skills, including 9-month-olds' ability to use eye gaze, facial expression, and gestures to communicate.

Altered Gray-White Matter Boundary Contrast in Toddlers at Risk for Autism Relates to Later Diagnosis of Autism Spectrum Disorder

BACKGROUND

Recent neuroimaging studies have highlighted differences in cerebral maturation in individuals with autism spectrum disorder (ASD) in comparison to typical development. For instance, the contrast of the gray-white matter boundary is decreased in adults with ASD. To determine how gray-white matter boundary integrity relates to early ASD phenotypes, we used a regional structural MRI index of gray-white matter contrast (GWC) on a sample of toddlers with a hereditary high risk for ASD.

MATERIALS AND METHODS

We used a surface-based approach to compute vertex-wise GWC in a longitudinal cohort of toddlers at high-risk for ASD imaged twice between 12 and 24 months (n = 20). A full clinical assessment of ASD-related symptoms was performed in conjunction with imaging and again at 3 years of age for diagnostic outcome. Three outcome groups were defined (ASD, n = 9; typical development, n = 8; non-typical development, n = 3).

RESULTS

ASD diagnostic outcome at age 3 was associated with widespread increases in GWC between age 12 and 24 months. Many cortical regions were affected, including regions implicated in social processing and language acquisition. In parallel, we found that early onset of ASD symptoms (i.e., prior to 18-months) was specifically associated with slower GWC rates of change during the second year of life. These alterations were found in areas mainly belonging to the central executive network.

LIMITATIONS

Our study is the first to measure maturational changes in GWC in toddlers who developed autism, but given the limited size of our sample results should be considered exploratory and warrant further replication in independent and larger samples.

CONCLUSION

These preliminary results suggest that ASD is linked to early alterations of the gray-white matter boundary in widespread brain regions. Early onset of ASD diagnosis constitutes an independent clinical parameter associated with a specific corresponding neurobiological developmental trajectory. Altered neural migration and/or altered myelination processes potentially explain these findings.

Multimodal Communication in Children with Autism Spectrum Disorder and Different Linguistic Development

This study focuses on the multimodal communication of children with autism spectrum disorders (ASD) compared to typically developing (TD) children. Eleven children with ASD (aged from 28 to 79 months) and 11 TD children (from 12 to 30 months) were matched by their productive vocabulary. We observed their communicative production in a semi-structured play situation. Results showed no differences in the combinations of gestural and vocal elements between children with ASD and TD. By contrast, regarding the production of the three-element multimodal combinations, we found a different pattern between ASD and TD children depending on their lexical development. These results provide clues to understand some controversial findings regarding multimodal production of people with ASD described in the literature.

Measuring social-communication difficulties in school-age siblings of children with autism spectrum disorder: Standardized versus naturalistic assessment

Younger siblings of children with autism spectrum disorder (ASD; high-risk siblings) are at elevated risk for developing the broader autism phenotype (BAP), which consists of subclinical features of ASD. We examined conversational skills in a naturalistic context and standardized assessments of pragmatic language and communication skills in high-risk and low-risk school-age children with BAP (n = 22) and ASD (n = 18) outcomes, as well as comparison children without ASD or BAP (n = 135). Children with BAP characteristics exhibited lower conversational skills than comparison children, but did not differ on any of three standardized measures. Only the conversational ratings significantly predicted membership in the BAP versus Comparison group. This suggests that naturalistic tasks are crucial when assessing social-communication difficulties in children with a family history of ASD. LAY SUMMARY: The broader autism phenotype (BAP) consists of subclinical features of autism spectrum disorder (ASD) and is more common among family members of those with ASD. School-age children with BAP characteristics exhibited lower conversational skills than comparison children, but did not differ on standardized language measures tapping similar abilities. This suggests that naturalistic tasks may be more sensitive to the social-communication difficulties seen in some children with a family history of ASD than the standardized language tests used in most evaluations.

The associations between autistic and communication traits in parents and developmental outcomes in children at familial risk of autism at 6 and 24 months of age

BACKGROUND

Several studies have explored relationships between parent broader autism phenotype and offspring communication, and have reported that autistic-like traits in parents are related to offspring communication difficulties and autism severity. However, past research has focused on studying such associations in childhood and we know very little about them in infancy. With accumulating evidence that interventions administered during infancy may be most effective in reducing ASD symptoms, it is imperative to examine whether relationships between parent autistic-like traits and child communication appear even earlier during this critical period of life.

METHOD

This longitudinal study collected data from infant siblings of autistic children (N = 32) and infants with no family history of autism (N = 45) to explore how autistic-like traits in parents related to child developmental outcomes during infancy.

RESULTS

Parental communication difficulties and autistic-like traits were found to be associated with a range of child behaviours in the first two years of life, including social-emotional difficulties at 6 and 24 months, lower communication and emerging cognition at 24 months, and increased autistic behaviours at 24 months.

CONCLUSIONS

Based on the results, it appears that some of the difficulties seen in parents are relayed to children genetically. These findings contribute to ASD research concerning early communication development in children and heritability of ASD traits and may have important implications in monitoring child development. Furthermore, since the current study found a significant association between autistic traits in parents and child social-emotional behaviour as early as 6 months of age, it provides evidence of the value of assessing interventions that target infancy.

Beyond Baby Siblings-Expanding the Definition of "High-Risk Infants" in Autism Research

PURPOSE OF REVIEW

Much of our understanding of early development in children with autism spectrum disorder (ASD) comes from studies of children with a family history of autism. We reviewed the current literature on neurodevelopmental profiles and autism prevalence from other high-risk infant groups to expose gaps and inform next steps. We focused on infants with early medical risk (e.g., preterm birth) and genetic risk (tuberous sclerosis complex [TSC]).

RECENT FINDINGS

About 7% of very preterm infants are later diagnosed with ASD. Prospective studies of early development outside of familial-risk infants are rare; however, recent work within preterm and TSC infants suggests interesting similarities and differences from infants with a family history of ASD. It is essential that we extend our knowledge of early markers of ASD beyond familial-risk infants to expand our knowledge of autism as it emerges in order to develop better, more individualized early interventions.

Bayesian Weighted Sums: A Flexible Approach to Estimate Summed Mixture Effects

OBJECTIVES

Methods exist to study exposure mixtures, but each is distinct in the research question it aims to address. We propose a new approach focused on estimating both the summed effect and individual weights of one or multiple exposure mixtures: Bayesian Weighted Sums (BWS).

METHODS

We applied BWS to simulated and real datasets with correlated exposures. The analytic context in our real-world example is an estimation of the association between polybrominated diphenyl ether (PBDE) congeners (28, 47, 99, 100, and 153) and Autism Spectrum Disorder (ASD) diagnosis and Social Responsiveness Scores (SRS).

RESULTS

Simulations demonstrate that BWS performs reliably. In adjusted models using Early Autism Risk Longitudinal Investigation (EARLI) data, the odds of ASD for a 1-unit increase in the weighted sum of PBDEs were 1.41 (95% highest posterior density 0.82, 2.50) times the odds of ASD for the unexposed and the change in z-score standardized SRS per 1 unit increase in the weighted sum of PBDEs is 0.15 (95% highest posterior density -0.08, 0.38).

CONCLUSIONS

BWS provides a means of estimating the summed effect and weights for individual components of a mixture. This approach is distinct from other exposure mixture tools. BWS may be more flexible than existing approaches and can be specified to allow multiple exposure groups based on a priori knowledge from epidemiology or toxicology.

Down Syndrome and Autism Spectrum Disorder Dual Diagnosis: Important Considerations for Speech-Language Pathologists

Purpose Individuals with Down syndrome (DS) often receive speech-language therapy services starting in infancy or toddlerhood. When providing speech-language therapy services for children with DS, speech-language pathologists (SLPs) need to consider the impact of other developmental and comorbid disorders that can affect language development, such as the presence of a dual diagnosis of DS and autism spectrum disorder (DS + ASD). The prevalence rate of ASD in DS is ~20%, which is higher than in the general population. Method This clinical focus article aims to provide SLPs with additional knowledge about DS + ASD to improve service delivery and support parents' ability to advocate for their child with confirmed or suspected DS + ASD. This is accomplished by summarizing the current evidence base on the presence of ASD in DS and discussing implications of a DS + ASD diagnosis for clinical practice with SLPs. Conclusions SLPs play a key role in supporting families of those with DS + ASD by advocating and educating. By understanding the unique profiles of strengths and weaknesses of individuals with DS + ASD, SLPs can provide appropriate service delivery (i.e., treatment and intervention approaches) and advocacy for their clients and their families.

Context-Specific Dyadic Attention Vulnerabilities During the First Year in Infants Later Developing Autism Spectrum Disorder

OBJECTIVE

Although some eye-tracking studies demonstrate atypical attention to faces by 6 months of age in autism spectrum disorder (ASD), behavioral studies in early infancy return largely negative results. We examined the effects of context and diagnosis on attention to faces during face-to-face live interactions in infants at high familial risk (HR) and low familial risk (LR) for ASD.

METHOD

Participants were 6-, 9-, and 12-month-old siblings of children with ASD who were later determined to have ASD (n = 21), other developmental challenges (HR-C; n = 74), or typical development (TD) (HR-TD; n = 32), and low-risk, typically developing controls (LR-TD; n = 49). Infants were administered the social orienting probes task, consisting of five conditions: dyadic bid, song, peek-a-boo, tickle, and toy play. Attention to an unfamiliar examiner's face was coded by blinded raters from video recordings.

RESULTS

At all ages, the ASD group spent less time looking at the examiner's face than the HR-C, HR-TD, and LR-TD groups during the Dyadic Bid and Tickle conditions (all p <.05), but not during the Song, Peek-a-Boo, or Toy Play conditions (all p >.23). Lower attention to faces during Dyadic Bid and Tickle conditions was significantly correlated with higher severity of autism symptoms at 18 months.

CONCLUSION

During the prodromal stages of the disorder, infants with ASD exhibited subtle impairments in attention to faces of interactive partners during interactions involving eye contact and child-directed speech (with and without physical contact), but not in contexts involving singing, familiar anticipatory games, or toy play. Considering the convergence with eye-tracking findings on limited attention to faces in infants later diagnosed with ASD, reduced attention to faces of interactive partners in specific contexts may constitute a promising candidate behavioral marker of ASD in infancy.