A Pilot Randomized Controlled Trial of Motivation-Based Social Skills Group Treatment with Parent Training.

Despite the popularity of social skills groups, there remains a need for empirical investigation of treatment effects, especially when targeting pivotal aspects of social functioning such as initiations to peers. The goal of the present study was to conduct a randomized controlled trial of a 12-week social intervention (SUCCESS), which combined an inclusive social group with a parent education program. Twenty-five 4- to 6-year-olds with Autism Spectrum Disorder (ASD) were randomized to SUCCESS (N = 11) or to treatment as usual (N = 14). Combining a peer group model with a parent training program, the SUCCESS intervention used naturalistic behavioral techniques (e.g., environmental arrangement, natural reinforcement) to increase social initiations to peers. After 12 weeks, children participating in the SUCCESS program made more frequent initiations to peers than children in the treatment-as-usual group, including more prompted and unprompted initiations to request. Additional gains in clinician-rated social functioning were observed in children randomized to SUCCESS, while differential treatment effects were not detected in parent-rated measures. However, lower baseline social motivation was associated with greater parent-reported initiation improvement. This study provides preliminary support for the efficacy of a naturalistic, behavioral social skills intervention to improve peer initiations for children with ASD. The findings suggest that using a motivation-based social skills group was effective in increasing both prompted and spontaneous initiations to peers, and highlights the need for further research into the role of baseline social motivation in predicting social skills treatment response.

A Twin Study of Altered White Matter Heritability in Youth With Autism Spectrum Disorder.

OBJECTIVE: White matter alterations are frequently reported in autism spectrum disorder (ASD), yet the etiology is currently unknown. The objective of this investigation was to examine, for the first time, the impact of genetic and environmental factors on white matter microstructure in twins with ASD compared to control twins without ASD. METHOD: Diffusion-weighted MRIs were obtained from same-sex twin pairs (6-15 years of age) in which at least 1 twin was diagnosed with ASD or neither twin exhibited a history of neurological or psychiatric disorders. Fractional anisotropy (FA) and mean diffusivity (MD) were examined across different white matter tracts in the brain, and statistical and twin modeling were completed to assess the proportion of variation associated with additive genetic (A) and common/shared (C) or unique (E) environmental factors. We also developed a novel Twin-Pair Difference Score analysis method that produces quantitative estimates of the genetic and environmental contributions to shared covariance between different brain and behavioral traits. RESULTS: Good-quality data were available from 84 twin pairs, 50 ASD pairs (32 concordant for ASD [16 monozygotic; 16 dizygotic], 16 discordant for ASD [3 monozygotic; 13 dizygotic], and 2 pairs in which 1 twin had ASD and the other exhibited some subthreshold symptoms [1 monozygotic; 1 dizygotic]) and 34 control pairs (20 monozygotic; 14 dizygotic). Average FA and MD across the brain, respectively, were primarily genetically mediated in both control twins (A = 0.80, 95% CI [0.57, 1.02]; A = 0.80 [0.55, 1.04]) and twins concordant for having ASD (A = 0.71 [0.33, 1.09]; A = 0.84 [0.32,1.36]). However, there were also significant tract-specific differences between groups. For instance, genetic effects on commissural fibers were primarily associated with differences in general cognitive abilities and perhaps some diagnostic differences for ASD because Twin-Pair Difference-Score analysis indicated that genetic factors may have contributed to ∼40% to 50% of the covariation between IQ scores and FA of the corpus callosum. Conversely, the increased impact of environmental factors on some projection and association fibers were primarily associated with differences in symptom severity in twins with ASD; for example, our analyses suggested that unique environmental factors may have contributed to ∼10% to 20% of the covariation between autism-related symptom severity and FA of the cerebellar peduncles and external capsule. CONCLUSION: White matter alterations in youth with ASD are associated with both genetic contributions and potentially increased vulnerability or responsivity to environmental influences. DIVERSITY & INCLUSION STATEMENT: We worked to ensure sex and gender balance in the recruitment of human participants. We worked to ensure race, ethnic, and/or other types of diversity in the recruitment of human participants. We worked to ensure that the study questionnaires were prepared in an inclusive way. One or more of the authors of this paper self-identifies as a member of one or more historically underrepresented racial and/or ethnic groups in science. One or more of the authors of this paper self-identifies as a member of one or more historically underrepresented sexual and/or gender groups in science. One or more of the authors of this paper self-identifies as living with a disability. The author list of this paper includes contributors from the location and/or community where the research was conducted and they participated in the data collection, design, analysis, and/or interpretation of the work.

NGLY1 deficiency: a prospective natural history study.

N-glycanase 1 (NGLY1) deficiency is a debilitating, ultra-rare autosomal recessive disorder caused by loss of function of NGLY1, a cytosolic enzyme that deglycosylates other proteins. It is characterized by severe global developmental delay and/or intellectual disability, hyperkinetic movement disorder, transient elevation of transaminases, (hypo)alacrima and progressive, diffuse, length-dependent sensorimotor polyneuropathy. A prospective natural history study (NHS) was conducted to elucidate clinical features and disease course. Twenty-nine participants were enrolled (15 onsite, 14 remotely) and followed for up to 32 months, representing ~29% of the ~100 patients identified worldwide. Participants exhibited profound developmental delays, with almost all developmental quotients below 20 on the Mullen Scales of Early Learning, well below the normative score of 100. Increased difficulties with sitting and standing suggested decline in motor function over time. Most patients presented with (hypo)alacrima and reduced sweat response. Pediatric quality of life was poor except for emotional function. Language/communication and motor skill problems including hand use were reported by caregivers as the most bothersome symptoms. Levels of the substrate biomarker, GlcNAc-Asn (aspartylglucosamine; GNA), were consistently elevated in all participants over time, independent of age. Liver enzymes were elevated for some participants but improved especially in younger patients and did not reach levels indicating severe liver disease. Three participants died during the study period. Data from this NHS informs selection of endpoints and assessments for future clinical trials for NGLY1 deficiency interventions. Potential endpoints include GNA biomarker levels, neurocognitive assessments, autonomic and motor function (particularly hand use), (hypo)alacrima and quality of life.

Aberrant Emotional Prosody Circuitry Predicts Social Communication Impairments in Children With Autism.

BACKGROUND: Emotional prosody provides acoustical cues that reflect a communication partner's emotional state and is crucial for successful social interactions. Many children with autism have deficits in recognizing emotions from voices; however, the neural basis for these impairments is unknown. We examined brain circuit features underlying emotional prosody processing deficits and their relationship to clinical symptoms of autism. METHODS: We used an event-related functional magnetic resonance imaging task to measure neural activity and connectivity during processing of sad and happy emotional prosody and neutral speech in 22 children with autism and 21 matched control children (7-12 years old). We employed functional connectivity analyses to test competing theoretical accounts that attribute emotional prosody impairments to either sensory processing deficits in auditory cortex or theory of mind deficits instantiated in the temporoparietal junction (TPJ). RESULTS: Children with autism showed specific behavioral impairments for recognizing emotions from voices. They also showed aberrant functional connectivity between voice-sensitive auditory cortex and the bilateral TPJ during emotional prosody processing. Neural activity in the bilateral TPJ during processing of both sad and happy emotional prosody stimuli was associated with social communication impairments in children with autism. In contrast, activity and decoding of emotional prosody in auditory cortex was comparable between autism and control groups and did not predict social communication impairments. CONCLUSIONS: Our findings support a social-cognitive deficit model of autism by identifying a role for TPJ dysfunction during emotional prosody processing. Our study underscores the importance of tuning in to vocal-emotional cues for building social connections in children with autism.

Dimensional Assessment of Restricted and Repetitive Behaviors: Development and Preliminary Validation of a New Measure.

OBJECTIVE: This study aimed to provide initial validation of the Dimensional Assessment of Restricted and Repetitive Behaviors (DARB), a new parent-report measure designed to capture the full range of key restricted and repetitive behaviors (RRB) subdomains. METHOD: Parents of 1,892 children and adolescents with autism spectrum disorder (mean [SD] age = 10.81 [4.14] years) recruited from the SPARK (Simons Foundation Powering Autism Research for Knowledge) research match completed the DARB, several existing RRB instruments, and measures of social and communication impairments and anxiety. A subsample of 450 parents completed the DARB after 2 weeks to evaluate the test-retest stability. RESULTS: Exploratory graph analysis conducted in the exploratory subsample identified 8 dimensions that were aligned with hypothesized RRB subdomains: repetitive sensory motor behaviors, insistence on sameness, restricted interests, unusual interests, sensory sensitivity, self-injurious behaviors, obsessions and compulsive behaviors, and repetitive language. The confirmatory application of the exploratory structural equation modeling conducted in the confirmatory subsample showed that the derived factor structure had a good fit to the data. Derived factors had excellent reliability, convergent and divergent validity, and very strong test-retest stability and showed a distinct pattern of associations with key demographic, cognitive and clinical correlates. CONCLUSION: The DARB will be useful in a variety of research and clinical contexts considering the prominence and clinical impact of RRB in autism spectrum disorder. Strong preliminary evidence indicates that the new scale is comprehensive and captures a wide range of distinct RRB subdomains not simultaneously captured by any of the existing instruments.

Delineating the epilepsy phenotype of NGLY1 deficiency.

We delineated the phenotypic spectrum of epilepsy in individuals with NGLY1 deficiency from an international cohort. We collected detailed clinical and electroencephalographic data from 29 individuals with bi-allelic (likely) pathogenic variants in NGLY1 as part of an ongoing prospective natural history study. Participants were evaluated in-person at a single center and/or remotely. Historical medical records were reviewed. Published cases were included for comprehensive phenotyping. Of 29 individuals (mean 11.4 years, range 3-27 years), 17 (58.6%) participants had a history of epilepsy. Seizure onset was in early childhood (mean 43 months, range 2 months to 19 years). The most common seizure types were myoclonic and atonic. Epilepsy course was variable, but 35.2% (6/17) of participants with epilepsy achieved seizure freedom. The most common medications included levetiracetam, valproate, lamotrigine, and clobazam. Electroencephalogram (EEGs) were abnormal in 80% (12/15) of participants with or without epilepsy, although encephalopathy was uncommon. There was a trend in neurodevelopmental outcomes that participants with epilepsy had more developmental delays. In summary, epilepsy is common in NGLY1 deficiency. Over half of the participants had a history of epilepsy and nearly all had EEG abnormalities indicating an increased risk of epilepsy. This work expands the electroclinical phenotype of NGLY1 deficiency and supports a high clinical suspicion for seizures. Some of the more common seizure types (epileptic spasms, myoclonic, and atonic seizures) can be subtle and require counseling to ensure early recognition and treatment to ensure the best possible outcomes. Despite transient liver enzyme abnormalities in this disorder, hepatically metabolized medications were well tolerated.

Psychiatric Characteristics Across Individuals With PTEN Mutations.

Germline heterozygous PTEN mutations have been associated with high prevalence of autism spectrum disorder (ASD) and elevated rates and severity of broadly defined behavioral problems. However, limited progress has been made toward understanding whether PTEN mutation is associated with specific psychiatric co-morbidity profiles when compared to idiopathic ASD. The current study aimed to utilize a cross-measure approach to compare concurrent psychiatric characteristics across children and adolescents with PTEN mutation with (PTEN-ASD; n = 38) and without ASD (PTEN-No ASD; n = 23), and ASD with macrocephaly but no PTEN mutation (macro-ASD; n = 25) using the Child Behavior Checklist (CBCL) and the Aberrant Behavior Checklist (ABC). There were significant group effects for the CBCL Internalizing and Externalizing broad symptom score, the majority of specific CBCL syndrome scores, and all ABC subscale scores. Post-hoc comparisons revealed greater behavioral symptoms in the ASD groups (PTEN-ASD and macro-ASD) compared to the PTEN-no ASD group on nearly all subtest scores examined. There were no statistically significant differences between the PTEN-ASD and macro-ASD groups; however, there was a trend for the macro-ASD group showing higher levels of aggressive behaviors. Our findings provide evidence of specific behavior profiles across PTEN-No ASD, PTEN-ASD, and macro-ASD groups and highlight the importance of early identification of behavioral vulnerabilities in individuals with PTEN mutations in order to provide access to appropriate evidence-based interventions.

Brief Report: Emotion Regulation Influences on Internalizing and Externalizing Symptoms Across the Normative-Clinical Continuum.

Emotion regulation is theorized to be a transdiagnostic process and has been empirically shown to be associated with various mental health and neurodevelopmental conditions. However, the relationship between emotion regulation and internalizing and externalizing symptoms has yet to be characterized in a sample of individuals spanning normative and atypical development. Therefore, this study aimed to provide initial evidence for emotion regulation as a transdiagnostic process of internalizing and externalizing symptoms in a community sample of adolescents with and without neuropsychiatric and neurodevelopmental conditions. The sample consisted of 1,705 caregivers of adolescents aged between 11 and 17 years (M age = 14.53, SD age = 1.96). Adolescents were typically developing or had a caregiver-reported diagnosis of autism spectrum disorder, attention-deficit hyperactivity disorder, or anxiety. The typically developing adolescents had significantly better caregiver-reported emotion regulation than adolescents with caregiver-reported neuropsychiatric and neurodevelopmental conditions. Additionally, emotion dysregulation significantly and positively correlated with and predicted internalizing and externalizing symptoms within each subgroup. Importantly, emotion dysregulation had a unique contribution to individual differences in the severity of internalizing and externalizing symptoms, above and beyond the diagnostic status. The research and translational implications of the study findings are discussed.

Relationship Between Social Motivation in Children With Autism Spectrum Disorder and Their Parents.

Impairment in social motivation (SM) has been suggested as a key mechanism underlying social communication deficits observed in autism spectrum disorder (ASD). However, the factors accounting for variability in SM remain poorly described and understood. The current study aimed to characterize the relationship between parental and proband SM. Data from 2,759 children with ASD (M age = 9.03 years, SD age = 3.57, 375 females) and their parents from the Simons Simplex Collection (SSC) project was included in this study. Parental and proband SM was assessed using previously identified item sets from the Social Responsiveness Scale (SRS). Children who had parents with low SM scores (less impairments) showed significantly lower impairments in SM compared to children who had either one or both parents with elevated SM scores. No parent-of-origin effect was identified. No significant interactions were found involving proband sex or intellectual disability (ID) status (presence/absence of ID) with paternal or maternal SM. This study establishes that low SM in children with ASD may be driven, in part, by lower SM in one or both parents. Future investigations should utilize larger family pedigrees, including simplex and multiplex families, evaluate other measures of SM, and include other related, yet distinct constructs, such as social inhibition and anhedonia. This will help to gain finer-grained insights into the factors and mechanisms accounting for individual differences in sociability among typically developing children as well as those with, or at risk, for developing ASD.

A case-control study of visual, auditory and audio-visual sensory interactions in children with autism spectrum disorder.

To assess the relative integrity of early visual and auditory processes in autism spectrum disorder (ASD), we used frequency-tagged visual and auditory stimulation and high-density electroencephalogram recordings of unimodal and dual-modality responses in a case-control design. To test for the specificity of effects on ASD, we recorded from a smaller group of children with attention-deficit hyperactivity disorder (ADHD). Horizontal 3 cycle per degree (cpd) gratings were presented at 5 Hz, and a random stream of /ba/, /da/, /ga/ syllables was presented at 6 Hz. Grating contrast response functions were measured unimodally and in the presence of a 64-dB auditory input. Auditory response functions were measured unimodally and in the presence of a 40% contrast grating. Children with ASD (n = 34) and ADHD (n = 13) showed a common lack of audio-visual interaction compared to typically developing children (n = 40) when measured at the first harmonic of the visual stimulus frequency. Both patient groups also showed depressed first harmonic responses at low contrast, but the ADHD group had consistently higher first-harmonic responses at high contrast. Children with ASD had a preferential loss of second-harmonic (transient) responses. The alteredtransient responses in ASD are likely to arise very early in the visual pathway and could thus have downstream consequences for many other visual mechanisms and processes. The alteration in audio-visual interaction could be a signature of a comorbid phenotype shared by ASD and ADHD, possibly due to alterations in attentional selection systems.

Language Improvement Following Pivotal Response Treatment for Children With Developmental Disorders.

Given the high prevalence of communication deficits in developmental disorders, there is need for efficient early interventions. The aim of this pilot study is to examine benefits of pivotal response treatment (PRT) for improving language in young children with developmental disorders without autism spectrum disorder. Parents of 15 children with developmental disorders received weekly PRT parent training for 12 weeks. Standardized parent-rated assessments were administered at baseline and post-treatment to measure changes in language. Structured laboratory observation indicated children demonstrated significantly greater frequency of utterances and improvement on standardized questionnaires measuring expressive language and adaptive communication skills following PRT. Findings suggest that PRT may be efficacious in improving language abilities among children with developmental disorders.

Quantifying Research Domain Criteria Social Communication Subconstructs Using the Social Communication Questionnaire in Youth.

Research Domain Criteria (RDoC) has posited a set of social dimensions that could be useful in identifying sources of individual variation in social impairments across neurodevelopmental disorders. The current investigation aimed to derive estimates of the RDoC social constructs from the Social Communication Questionnaire (SCQ) and examine whether RDoC social processes, as captured by the SCQ, are best represented by a dimensional, categorical, or hybrid model. Individual SCQ items from 4 databases were combined resulting in a total of 26,407 individuals (Mage = 8.13 years, SDage = 4.19; 69.1% male). The sample consisted of 60.0% of individuals with autism spectrum disorder (ASD), 6.8% with a range of neurodevelopmental disorders and 33.2% of siblings of individuals with ASD. Comparison of a range of factor solutions through the use of exploratory structural equation modeling and confirmatory factor analysis indicated that a 3-factor structure with separate attachment and affiliation, production of nonfacial and facial communication factors provided excellent fit to the data (comparative fit index = .989, Tucker-Lewis index = .984, root mean square error of approximation = .045). and robustness across clinical groups, age, sex, and verbal status. Comparison between the best-fitting factor analysis, latent class analysis, and factor mixture analysis solutions demonstrated that the RDoC social processes domain is best represented as dimensional. Our findings show promise for capturing some of the important RDoC social constructs using the SCQ but also highlight crucial areas for the development of new, dedicated dimensional measures.

Characterizing Emotion Recognition and Theory of Mind Performance Profiles in Unaffected Siblings of Autistic Children.

Emotion recognition skills and the ability to understand the mental states of others are crucial for normal social functioning. Conversely, delays and impairments in these processes can have a profound impact on capability to engage in, maintain, and effectively regulate social interactions. Therefore, this study aimed to compare the performance of 42 autistic children (Mage = 8.25 years, SD = 2.22), 45 unaffected siblings (Mage = 8.65 years, SD = 2.40), and 41 typically developing (TD) controls (Mage = 8.56 years, SD = 2.35) on the Affect Recognition (AR) and Theory of Mind (TOM) subtests of the Developmental Neuropsychological Assessment Battery. There were no significant differences between siblings and TD controls. Autistic children showed significantly poorer performance on AR when compared to TD controls and on TOM when compared to both TD controls and unaffected siblings. An additional comparison of ASD, unaffected sibling and TD control subsamples, matched on full-scale IQ, revealed no group differences for either AR or TOM. AR and TOM processes have received less research attention in siblings of autistic children and remain less well characterized. Therefore, despite limitations, findings reported here contribute to our growing understanding of AR and TOM abilities in siblings of autistic children and highlight important future research directions.

Complex Interplay Between Cognitive Ability and Social Motivation in Predicting Social Skill: A Unique Role for Social Motivation in Children With Autism.

Impairment in social interaction is a core feature of autism spectrum disorder (ASD), but the factors which contribute to this social skill deficiency are poorly understood. Previous research has shown that cognitive ability can impact social skill development in ASD. Yet, children with ASD whose cognitive abilities are in the normal range nevertheless demonstrate deficits in social skill. More recently, the social motivation theory of ASD has emerged as a framework by which to understand how failure to seek social experiences may lead to social skill deficits. This study was designed to better understand the relationships between cognitive ability, social motivation, and social skill in a well-characterized cohort of children with ASD (n = 79), their unaffected siblings (n = 50), and unrelated neurotypical controls (n = 60). The following instruments were used: The Stanford-Binet intelligence quotient (IQ), the Social Responsiveness Scale's Social Motivation Subscale, and the Vineland Adaptive Behavior Scales' Socialization Standard Score. We found that lower cognitive ability contributed to diminished social skill, but did so universally in all children. In contrast, social motivation strongly predicted social skill only in children with ASD, such that those with the lowest social motivation exhibited the greatest social skill impairment. Notably, this relationship was observed across a large range of intellectual ability but was most pronounced in those with IQs ≥ 80. These findings establish a unique link between social motivation and social skill in ASD and support the hypothesis that low social motivation may impair social skill acquisition in this disorder, particularly in children without intellectual disability. LAY SUMMARY: The relationships between cognitive ability, social motivation, and social skill are poorly understood. Here we report that cognitive ability predicts social skill in all children, whereas social motivation predicts social skill only in children with autism. These results establish a unique link between social motivation and social skill in autism, and suggest that low social motivation may impair social skill acquisition in this disorder, particularly in those without intellectual disability.

Exploring Social Subtypes in Autism Spectrum Disorder: A Preliminary Study.

Impairments in social functioning are considered a hallmark diagnostic feature of autism spectrum disorder (ASD). Yet, individuals diagnosed with ASD vary widely with respect to specific presentation, severity, and course across different dimensions of this complex symptom domain. The aim of this investigation was to utilize the Stanford Social Dimensions Scale (SSDS), a newly developed quantitative measure providing parental perspective on their child's social abilities, in order to explore the existence of homogeneous subgroups of ASD individuals who share unique profiles across specific dimensions of the social domain. Parents of 164 individuals with ASD (35 females, 129 males; meanage = 7.54 years, SD = 3.85) completed the SSDS, the Social Responsiveness Scale (SRS-2) and the Child Behavior Checklist (CBCL). Data on children's verbal and nonverbal intellectual functioning (FSIQ) were also collected. The Latent Profile Analysis was used to classify participants according to the pattern of SSDS subscale scores (Social Motivation, Social Affiliation, Expressive Social Communication, Social Recognition, and Unusual Approach). Five profiles were identified. Profiles did not differ in terms of chronological age nor gender distribution but showed distinct patterns of strengths and weaknesses across different social components rather than simply reflecting a severity gradient. Profiles were further differentiated in terms of cognitive ability, as well as ASD and internalizing symptom severity. The implications of current findings and the necessary further steps toward identifying subgroups of individuals with ASD who share particular constellation of strengths and weaknesses across key social domains as a way of informing personalized interventions are discussed. Autism Res 2020. © 2020 International Society for Autism Research, Wiley Periodicals, Inc. LAY SUMMARY: People with autism spectrum disorder (ASD) vary greatly in terms of their social abilities and social motivation. However, researchers lack measures that can fully assess different components of social functioning. This paper provides initial evidence for capturing subgroups of individuals with ASD with specific strengths and weakness across different aspects of social functioning. Autism Res 2020, 13: 1335-1342. © 2020 International Society for Autism Research, Wiley Periodicals, Inc.

Genetic and environmental influences on structural brain measures in twins with autism spectrum disorder.

Atypical growth patterns of the brain have been previously reported in autism spectrum disorder (ASD) but these alterations are heterogeneous across individuals, which may be associated with the variable effects of genetic and environmental influences on brain development. Monozygotic (MZ) and dizygotic (DZ) twin pairs with and without ASD (aged 6-15 years) were recruited to participate in this study. T1-weighted MRIs (n = 164) were processed with FreeSurfer to evaluate structural brain measures. Intra-class correlations were examined within twin pairs and compared across diagnostic groups. ACE modeling was also completed. Structural brain measures, including cerebral and cerebellar gray matter (GM) and white matter (WM) volume, surface area, and cortical thickness, were primarily influenced by genetic factors in TD twins; however, mean curvature appeared to be primarily influenced by environmental factors. Similarly, genetic factors accounted for the majority of variation in brain size in twins with ASD, potentially to a larger extent regarding curvature and subcortical GM; however, there were also more environmental contributions in twins with ASD on some structural brain measures, such that cortical thickness and cerebellar WM volume were primarily influenced by environmental factors. These findings indicate potential neurobiological outcomes of the genetic and environmental risk factors that have been previously associated with ASD and, although preliminary, may help account for some of the previously outlined neurobiological heterogeneity across affected individuals. This is especially relevant regarding the role of genetic and environmental factors in the development of ASD, in which certain brain structures may be more sensitive to specific influences.

Mapping the Research Domain Criteria Social Processes Constructs to the Social Responsiveness Scale.

OBJECTIVE: Research Domain Criteria (RDoC) operationalizes a set of basic social dimensions that can be used to deconstruct sources of variation in social impairments across affected individuals, regardless of their diagnostic status. This is a necessary step toward the development of etiologically based and individualized treatments. The main objective of this investigation was to derive estimations of the RDoC social constructs from the Social Responsiveness Scale (SRS-2). METHOD: Exploratory structural equation modeling and confirmatory factor analysis were conducted using individual SRS-2 items from six distinct databases ( N = 27,953; mean age = 9.55 years, SD = 3.79; 71.7% male participants) spanning normative (33.8%) and atypical (66.2%) development. The following models were estimated: a one-factor model; a three-factor model with separate attachment and affiliation, social communication, and understanding of mental states factors; and a four-factor model where social communication was further split into production of facial and non-facial communication. RESULTS: The one-factor solution showed poor fit. The three-factor solution had adequate fit (comparative fit index = 0.952, Tucker Lewis Index = 0.937, root mean square error of approximation = 0.054). However, the four-factor solution had superior fit (comparative fit index = 0.973, Tucker Lewis Index = 0.961, root mean square error of approximation = 0.042) and was robust across age, sex, and clinical status. CONCLUSION: To our knowledge, this is the first study examining estimations of the RDoC social constructs from an existing measure. Reported findings show promise for capturing important RDoC social constructs using the SRS-2 and highlight crucial areas for the development of novel dimensional social processing measures.

Genetic and environmental influences on corticostriatal circuits in twins with autism

Background: Corticostriatal circuits (CSC) have been implicated in the presentation of some restricted and repetitive behaviours (RRBs) in children with autism-spectrum disorder (ASD), and preliminary evidence suggests that disruptions in these pathways may be associated with differences in genetic and environmental influences on brain development. The objective of this investigation was to examine the impact of genetic and environmental factors on CSC regions in twins with and without ASD and to evaluate their relationship with the severity of RRBs. Methods: We obtained T1-weighted MRIs from same-sex monozygotic and dizygotic twin pairs, aged 6­15 years. Good-quality data were available from 48 ASD pairs (n = 96 twins; 30 pairs concordant for ASD, 15 monozygotic and 15 dizygotic; 18 pairs discordant for ASD, 4 monozygotic and 14 dizygotic) and 34 typically developing control pairs (n = 68 twins; 20 monozygotic and 14 dizygotic pairs). We generated structural measures of the orbitofrontal cortex (OFC), anterior cingulate cortex (ACC), caudate, putamen, pallidum and thalamus using FreeSurfer. Twin pair comparisons included intraclass correlation analyses and ACE modelling (a2 = additive genetics; c2 = common or shared environment; e2 = unique or nonshared environment). We also assessed correlations with RRB severity. Results: Structural variation in CSC regions was predominantly genetically mediated in typically developing twins (a2 = 0.56 to 0.87), except for ACC white matter volume (a2 = 0.42, 95% confidence interval [CI] 0.08 to 0.77). We also observed similar magnitudes of genetic influence in twins with ASD (a2 = 0.65 to 0.97), but the cortical thickness of the ACC (c2 = 0.44, 95% CI 0.22 to 0.66) and OFC (c2 = 0.60, 95% CI 0.25 to 0.95) was primarily associated with environmental factors in only twins with ASD. Twin pair differences in OFC grey matter volume were also correlated with RRB severity and were predominantly environmentally mediated. Limitations: We obtained MRIs on 2 scanners, and analytical approaches could not identify specific genetic and environmental factors. Conclusion: Genetic factors primarily contribute to structural variation in subcortical CSC regions, regardless of ASD, but environmental factors may exert a greater influence on the development of grey matter thickness in the OFC and ACC in children with ASD. The increased vulnerability of OFC grey matter to environmental influences may also mediate some heterogeneity in RRB severity in children with ASD.

Genetic and Environmental Influences on Lobar Brain Structures in Twins With Autism.

This investigation examined whether the variation of cerebral structure is associated with genetic or environmental factors in children with autism spectrum disorder (ASD) compared with typically developing (TD) controls. T1-weighted magnetic resonance imaging scans were obtained from twin pairs (aged 6-15 years) in which at least one twin was diagnosed with ASD or both were TD. Good quality data were available from 30 ASD, 18 discordant, and 34 TD pairs (n = 164). Structural measures (volume, cortical thickness, and surface area) were generated with FreeSurfer, and ACE modeling was completed. Lobar structures were primarily genetically mediated in TD twins (a2 = 0.60-0.89), except thickness of the temporal (a2 = 0.33 [0.04, 0.63]) and occipital lobes (c2 = 0.61 [0.45, 0.77]). Lobar structures were also predominantly genetically mediated in twins with ASD (a2 = 0.70-1.00); however, thickness of the frontal (c2 = 0.81 [0.71, 0.92]), temporal (c2 = 0.77 [0.60, 0.93]), and parietal lobes (c2 = 0.87 [0.77, 0.97]), and frontal gray matter (GM) volume (c2 = 0.79 [0.63, 0.95]), were associated with environmental factors. Conversely, occipital thickness (a2 = 0.93 [0.75, 1.11]) did not exhibit the environmental contributions that were found in controls. Differences in GM volume were associated with social communication impairments for the frontal (r = 0.52 [0.18, 0.75]), temporal (r = 0.61 [0.30, 0.80]), and parietal lobes (r = 0.53 [0.19, 0.76]). To our knowledge, this is the first investigation to suggest that environmental factors influence GM to a larger extent in children with ASD, especially in the frontal lobe.

A Pivotal Response Treatment Package for Children With Autism Spectrum Disorder: An RCT.

OBJECTIVES: Our aim was to conduct a randomized controlled trial to evaluate a pivotal response treatment package (PRT-P) consisting of parent training and clinician-delivered in-home intervention on the communication skills of children with autism spectrum disorder. METHODS: Forty-eight children with autism spectrum disorder and significant language delay between 2 and 5 years old were randomly assigned to PRT-P (n = 24) or the delayed treatment group (n = 24) for 24 weeks. The effect of treatment on child communication skills was assessed via behavioral coding of parent-child interactions, standardized parent-report measures, and blinded clinician ratings. RESULTS: Analysis of child utterances during the structured laboratory observation revealed that, compared with the delayed treatment group, children in PRT-P demonstrated greater improvement in frequency of functional utterances (F1,41 = 6.07; P = .026; d = 0.61). The majority of parents in the PRT-P group (91%) were able to implement pivotal response treatment (PRT) with fidelity within 24 weeks. Children receiving PRT-P also demonstrated greater improvement on the Brief Observation of Social Communication Change, on the Clinical Global Impressions Improvement subscale, and in number of words used on a parent-report questionnaire. CONCLUSIONS: This is the first 24-week randomized controlled trial in which community treatment is compared with the combination of parent training and clinician-delivered PRT. PRT-P was effective for improving child social communication skills and for teaching parents to implement PRT. Additional research will be needed to understand the optimal combination of treatment settings, intensity, and duration, and to identify child and parent characteristics associated with treatment response.