Clinical, genetic, and cognitive correlates of seizure occurrences in Phelan-McDermid syndrome.

BACKGROUND: Phelan-McDermid syndrome (PMS) is a genetic neurodevelopmental disorder caused by SHANK3 haploinsufficiency and is associated with an increased risk for seizures. Previous literature indicates that around one third of individuals with PMS also have epilepsy or seizures, with a wide range of types and ages of onset. Investigating the impact of seizures on intellectual and adaptive functioning for PMS is a primary concern for caregivers and is important to understanding the natural history of this syndrome. METHODS: We report on results from 98 individuals enrolled in a prospective, longitudinal study. We detailed seizure frequency, type, and age of onset, and we analyzed seizure occurrence with best estimate IQ, adaptive functioning, clinical features, and genotype. We conducted multiple linear regression analyses to assess the relationship between the presence of seizures and the Vineland Adaptive Behavior Scale, Second Edition (VABS-II) Adaptive Behavior Composite score and the best estimate full-scale IQ. We also performed Chi-square tests to explore associations between seizure prevalence and genetic groupings. Finally, we performed Chi-square tests and t-tests to explore the relationship between seizures and demographic features, features that manifest in infancy, and medical features. RESULTS: Seizures were present in 41% of the cohort, and age of onset was widely variable. The presence of seizures was associated with significantly lower adaptive and intellectual functioning. Genotype-phenotype analyses were discrepant, with no differences in seizure prevalence across genetic classes, but with more genes included in deletions of participants with 22q13 deletions and seizures compared to those with 22q13 deletions and no seizures. No clinical associations were found between the presence of seizures and sex, history of pre- or neonatal complications, early infancy, or medical features. In this cohort, generalized seizures were associated with developmental regression, which is a top concern for PMS caregivers. CONCLUSIONS: These results begin to eludicate correlates of seizures in individuals with PMS and highlight the importance of early seizure management. Importantly, presence of seizures was associated with adaptive and cognitive functioning. A larger cohort might be able to identify additional associations with medical features. Genetic findings suggest an increased capability to realize genotype-phenotype relationships when deletion size is taken into account.

Community-based care for autistic youth: community providers' reported use of treatment practices in the United States.

Introduction: To illustrate the landscape of community-based care for autistic youth in the United States, we identified transdisciplinary psychosocial intervention practice sets that community providers report utilizing to care for this population, and examined characteristics associated with provider-reported utilization. Methods: The Usual Care for Autism Study (UCAS) Survey assessed provider demographics and provider-reported use of transdisciplinary practices for common ASD co-occurring problems: social difficulties, externalizing behaviors, and anxiety. Community practitioners (N = 701) from allied health, behavioral, education, medical, mental health and other disciplines who treat or work with autistic youth (7-22 years) participated. Results: Exploratory factor analysis yielded four factors: Consequence-Based Strategies (CBS), Cognitive-Behavioral and Therapy Strategies (CBTS), Antecedent-Based Strategies (ABS), and Teaching Strategies (TS). Providers across disciplines reported utilizing ABS more often than other sets. Providers from behavioral disciplines, with less than 4-year or Master degrees, or with more experience reported the most use of ABS, CBS and CBTS. Medical and behavioral providers reported the most use of TS. Setting and child characteristics were associated with practice set use, indicating variability by disability and client socioeconomic status. Discussion: Findings reflect the complexity and inconsistency of the service landscape for autistic youth across the U.S. Only by understanding the service landscape and predictors of practice utilization, can researchers, policymakers, provider groups, and the autistic community facilitate effective implementation strategy development and use to ultimately improve community-based care.

Provider Self-Reported Use and Usefulness of Intervention Strategies for Externalizing Behaviors in Youths with ASD.

OBJECTIVE: To examine predictors of implementation and perceived usefulness of four empirically supported strategies for treating externalizing behavior in youths with ASD. METHOD: Participants were 557 providers in the United States with experience treating externalizing behavior in youths with ASD. Generalized estimating equations were used to determine whether self-reported use and usefulness of four empirically supported intervention strategies (functional communication training, functional behavior analysis, visual tools/supports, token economy) were predicted by key provider characteristics: professional discipline, experience, and practice specialization (across three indices) in ASD. Post-hoc contrasts were performed to identify provider groups reporting the greatest use and usefulness of the four strategies. RESULTS: Strategies were most often used by providers with behavioral backgrounds, though perceived usefulness of strategies varied by providers' professional discipline. Compared to providers with more than 10 years of experience, less experienced providers endorsed the highest average use and usefulness of almost all strategies. Regarding ASD practice specialization, a lower volume of ASD cases, treating fewer youths with ASD over a 5-year period, and having a higher proportion of practice time working with youths with ASD reported were associated with greater use and usefulness of the strategies. CONCLUSIONS: Empirically supported strategies are widely used by and perceived as useful by providers who treat youths with ASD and co-occurring externalizing behaviors. Use and usefulness varies based on provider discipline, experience, and ASD practice specialization.

Updated consensus guidelines on the management of Phelan-McDermid syndrome.

Phelan-McDermid syndrome (PMS) is a genetic condition caused by SHANK3 haploinsufficiency and characterized by a wide range of neurodevelopmental and systemic manifestations. The first practice parameters for assessment and monitoring in individuals with PMS were published in 2014; recently, knowledge about PMS has grown significantly based on data from longitudinal phenotyping studies and large-scale genotype-phenotype investigations. The objective of these updated clinical management guidelines was to: (1) reflect the latest in knowledge in PMS and (2) provide guidance for clinicians, researchers, and the general community. A taskforce was established with clinical experts in PMS and representatives from the parent community. Experts joined subgroups based on their areas of specialty, including genetics, neurology, neurodevelopment, gastroenterology, primary care, physiatry, nephrology, endocrinology, cardiology, gynecology, and dentistry. Taskforce members convened regularly between 2021 and 2022 and produced specialty-specific guidelines based on iterative feedback and discussion. Taskforce leaders then established consensus within their respective specialty group and harmonized the guidelines. The knowledge gained over the past decade allows for improved guidelines to assess and monitor individuals with PMS. Since there is limited evidence specific to PMS, intervention mostly follows general guidelines for treating individuals with developmental disorders. Significant evidence has been amassed to guide the management of comorbid neuropsychiatric conditions in PMS, albeit mainly from caregiver report and the experience of clinical experts. These updated consensus guidelines on the management of PMS represent an advance for the field and will improve care in the community. Several areas for future research are also highlighted and will contribute to subsequent updates with more refined and specific recommendations as new knowledge accumulates.

Examining indicators of psychosocial risk and resilience in parents of autistic children.

Background: Parents of autistic children experience increased levels of caregiver strain and adverse mental health outcomes, even in comparison to parents of children with other neurodevelopmental disabilities. Previous studies have largely attributed these increased levels of mental health concerns to their child behavioral concerns and autism symptomatology, but less attention has been given to other potential child factors, such as child adaptive functioning. Additionally, little is known about potential protective factors, such as parents' emotion regulation (ER) abilities, that may ameliorate the experience of caregiver strain, anxiety, and depression. Objective: The current study examined the impact of child characteristics (restricted and repetitive behaviors, adaptive functioning and behavioral concerns) on parent mental health outcomes (caregiver strain, anxiety, depression and wellbeing). Additionally, we explore parents' ER abilities as a moderator of the impact of child characteristic on parents' mental health outcomes. Results: Results of linear mixed effect models indicated a significant relationship between parents' ER abilities and all four parent outcomes. Additionally, children's adaptive functioning abilities and repetitive behaviors (RRBs) were significant predictors of caregiving strain. Parents' ER abilities were a significant moderator of the effect of children's repetitive behaviors and adaptive functioning challenges on caregiver strain, such that better ER abilities mitigated the impact of child clinical factors on caregiver strain. Finally, a significant difference was detected for mothers' and fathers' mental health, with mothers reporting higher caregiver strain, and more symptoms of anxiety and depression than did fathers. Conclusion: This study leveraged a large sample of autistic children and their biological parents to examine the relationship between children's clinical characteristics and parents' psychological wellbeing. Results indicate that, although parents of autistic children do experience high rates of internalizing mental health concerns that relate to child adaptive functioning and RRBs, parent ER abilities act as a protective factor against parents' adverse mental health outcomes. Further, mothers in our sample reported significantly higher rates of depression, anxiety, and caregiver strain, as compared with fathers.

Large 22q13.3 deletions perturb peripheral transcriptomic and metabolomic profiles in Phelan-McDermid syndrome.

Phelan-McDermid syndrome (PMS) is a rare neurodevelopmental disorder caused at least in part by haploinsufficiency of the SHANK3 gene, due to sequence variants in SHANK3 or subtelomeric 22q13.3 deletions. Phenotypic differences have been reported between PMS participants carrying small "class I" mutations and large "class II" mutations; however, the molecular perturbations underlying these divergent phenotypes remain obscure. Using peripheral blood transcriptome and serum metabolome profiling, we examined the molecular perturbations in the peripheral circulation associated with a full spectrum of PMS genotypes spanning class I (n = 37) and class II mutations (n = 39). Transcriptomic data revealed 52 genes with blood expression profiles that tightly scale with 22q.13.3 deletion size. Furthermore, we uncover 208 underexpressed genes in PMS participants with class II mutations, which were unchanged in class I mutations. These genes were not linked to 22q13.3 and were strongly enriched for glycosphingolipid metabolism, NCAM1 interactions, and cytotoxic natural killer (NK) immune cell signatures. In silico predictions estimated a reduction in CD56+ CD16- NK cell proportions in class II mutations, which was validated by mass cytometry time of flight. Global metabolomics profiling identified 24 metabolites that were significantly altered in PMS participants with class II mutations and confirmed a general reduction in sphingolipid metabolism. Collectively, these results provide new evidence linking PMS participants carrying class II mutations with decreased expression of cytotoxic cell signatures, reduced relative proportions of NK cells, and lower sphingolipid metabolism. These findings highlight alternative avenues for therapeutic development and offer new mechanistic insights supporting genotype-to-phenotype associations in PMS.

Usual care for youth with autism spectrum disorder: Community-based providers' reported familiarity with treatment practices.

Objective: To examine patterns and predictors of familiarity with transdisciplinary psychosocial (e.g., non-pharmacologic) practices for practitioners treating youths with autism spectrum disorder (ASD) in the United States. Method: Practitioners (n = 701) from behavioral, education, medical, and mental health backgrounds who worked with youth (ages 7-22) with ASD completed the Usual Care for Autism Survey, which assessed provider demographics and self-reported familiarity with transdisciplinary treatment practices for the most common referral problems of ASD. We examined relations between provider-, setting-, and client-level characteristics with familiarity of key groups of the treatment practices (practice sets). Practice sets were identified using exploratory factor analysis (EFA), and demographic predictors of practice subsets were examined using generalized estimating equations (GEE). Results: The EFA yielded a three-factor solution: (1) environmental modifications/antecedent strategies; (2) behavior analytic strategies; and (3) cognitive strategies, with overall familiarity ranked in this order. Medical providers indicated the least familiarity across disciplines. More experience with ASD and treating those with intellectual disabilities predicted greater familiarity with only environmental modifications/antecedent strategies and behavior analytic, but not cognitive strategies. Experience treating low SES clients predicted familiarity with environmental modification and behavior analytic strategies while experience treating high SES clients predicted familiarity with behavior analytic and cognitive strategies. Conclusion: This is the first study to identify transdisciplinary, interpretable sets of practices for treating youth with ASD based on community providers' reported familiarity. Results highlight factors associated with familiarity with practice sets, which is essential for mapping practice availability, and optimizing training and dissemination efforts for youth with ASD.

Atypical Functional Connectivity During Unfamiliar Music Listening in Children With Autism.

Background: Atypical processing of unfamiliar, but less so familiar, stimuli has been described in Autism Spectrum Disorder (ASD), in particular in relation to face processing. We examined the construct of familiarity in ASD using familiar and unfamiliar songs, to investigate the link between familiarity and autism symptoms, such as repetitive behavior. Methods: Forty-eight children, 24 with ASD (21 males, mean age = 9.96 years ± 1.54) and 24 typically developing (TD) controls (21 males, mean age = 10.17 ± 1.90) completed a music familiarity task using individually identified familiar compared to unfamiliar songs, while magnetoencephalography (MEG) was recorded. Each song was presented for 30 s. We used both amplitude envelope correlation (AEC) and the weighted phase lag index (wPLI) to assess functional connectivity between specific regions of interest (ROI) and non-ROI parcels, as well as at the whole brain level, to understand what is preserved and what is impaired in familiar music listening in this population. Results: Increased wPLI synchronization for familiar vs. unfamiliar music was found for typically developing children in the gamma frequency. There were no significant differences within the ASD group for this comparison. During the processing of unfamiliar music, we demonstrated left lateralized increased theta and beta band connectivity in children with ASD compared to controls. An interaction effect found greater alpha band connectivity in the TD group compared to ASD to unfamiliar music only, anchored in the left insula. Conclusion: Our results revealed atypical processing of unfamiliar songs in children with ASD, consistent with previous studies in other modalities reporting that processing novelty is a challenge for ASD. Relatively typical processing of familiar stimuli may represent a strength and may be of interest to strength-based intervention planning.

Strong evidence for genotype-phenotype correlations in Phelan-McDermid syndrome: results from the developmental synaptopathies consortium.

Individuals with Phelan-McDermid syndrome (PMS) present with a wide range of developmental, medical, cognitive and behavioral abnormalities. Previous literature has begun to elucidate genotype-phenotype associations that may contribute to the wide spectrum of features. Here, we report results of genotype-phenotype associations in a cohort of 170 individuals with PMS. Genotypes were defined as Class I deletions (including SHANK3 only or SHANK3 with ARSA and/or ACR and RABL2B), Class II deletions (all other deletions) or sequence variants. Phenotype data were derived prospectively from direct evaluation, caregiver interview and questionnaires, and medical history. Analyses revealed individuals with Class I deletions or sequence variants had fewer delayed developmental milestones and higher cognitive ability compared to those with Class II deletions but had more skill regressions. Individuals with Class II deletions were more likely to have a variety of medical features, including renal abnormalities, spine abnormalities, and ataxic gait. Those with Class I deletions or sequence variants were more likely to have psychiatric diagnoses including bipolar disorder, depression, and schizophrenia. Autism spectrum disorder diagnoses did not differ between groups. This study represents the largest and most rigorous genotype-phenotype analysis in PMS to date and provides important information for considering clinical functioning, trajectories and comorbidities as a function of specific genetic alteration.

Parent-reported measure of repetitive behavior in Phelan-McDermid syndrome.

BACKGROUND: Phelan McDermid syndrome (PMS) is a neurogenetic condition associated with a high prevalence of intellectual disability (ID) and autism spectrum disorder (ASD). This study provides a more comprehensive and quantitative profile of repetitive behaviors within the context of ID seen with the condition. METHODS: Individuals age 3-21 years with a confirmed PMS diagnosis participated in a multicenter observational study evaluating the phenotype and natural history of the disorder. We evaluated data collected from this study pertaining to repetitive behaviors from the Repetitive Behavior Scales-Revised (RBS-R). RESULTS: There were n = 90 participants who were part of this analysis. Forty-seven percent (n = 42/90) were female, and the average age at baseline evaluation was 8.88 ± 4.72 years. The mean best estimate IQ of the cohort was 26.08 ± 17.67 (range = 3.4-88), with n = 8 with mild ID (or no ID), n = 20 with moderate ID, and n = 62 with severe-profound ID. The RBS-R total overall score was 16.46 ± 13.9 (compared to 33.14 ± 20.60 reported in previous studies of ASD) (Lam and Aman, 2007), and the total number of items endorsed was 10.40 ± 6.81 (range = 0-29). After statistical correction for multiple comparisons, IQ correlated with the RBS-R stereotypic behavior subscale score (rs = - 0.33, unadjusted p = 0.0014, adjusted p = 0.01) and RBS-R stereotypic behavior total number of endorsed items (rs = - 0.32, unadjusted p = 0.0019, adjusted p = 0.01). IQ did not correlate with any other RBS-R subscale scores. CONCLUSIONS: The RBS-R total overall score in a PMS cohort appears milder compared to individuals with ASD characterized in previous studies. Stereotypic behavior in PMS may reflect cognitive functioning.

Social cognitive skills groups increase medial prefrontal cortex activity in children with autism spectrum disorder.

Few studies have examined the neural mechanisms of change following social skills interventions for children with autism spectrum disorder (ASD). This study examined the neural effects of social cognitive skills groups during functional MRI (fMRI) tasks of irony comprehension and eye gaze processing in school-aged children with ASD. Verbally fluent children (ages 8-11) were randomized to social cognitive skills groups or facilitated play comparison groups. Behavioral assessments and fMRI scans were obtained at baseline and endpoint (12 weeks). During fMRI, children completed two separate tasks to engage social cognition circuitry: comprehension of potentially ironic scenarios (n = 34) and viewing emotionally expressive faces with direct or averted gaze (n = 24). Whole-brain analyses were conducted to examine neural changes following treatment. Regression analyses were also conducted to explore the relationship between neural and behavioral changes. When comparing the two groups directly, the social cognitive skills group showed greater increases in activity in the medial prefrontal cortex (mPFC), implicated in theory of mind, relative to the comparison group for both irony comprehension and gaze processing tasks. Increased mPFC activity during the irony task was associated with improvement in social functioning on the Social Responsiveness Scale across both groups. Findings indicate that social cognitive skills interventions may increase activity in regions associated with social cognition and mentalizing abilities. LAY SUMMARY: Social skills groups are a common intervention for school-aged children with ASD. However, few studies have examined the neural response to social skills groups in school-aged children with ASD. Here, we report on a study evaluating neural outcomes from an empirically supported social cognitive skills training curriculum using fMRI. This study seeks to understand the effects of targeting emotion recognition and theory of mind on the brain circuitry involved in social cognition in verbally fluent children ages 8-11. Results indicate increased neural activity in the mPFC, a region considered to be a central hub of the "social brain," in children randomized to social cognitive skills groups relative to a comparison group that received a high-quality, child-directed play approach. In addition, increased activation in the mPFC during an irony comprehension task was associated with gains in social functioning across both groups from pre- to post-treatment. This is the first fMRI study of social skills treatment outcomes following a randomized trial with an active treatment condition in school-aged children with ASD.

Neurocognitive Outcomes from Memantine: A Pilot, Double-Blind, Placebo-Controlled Trial in Children with Autism Spectrum Disorder.

Objective: Studies interrogating therapeutics which alter the excitation-inhibition balance in the treatment of autism spectrum disorder (ASD) have reported mixed results on social and behavioral outcomes. Methods: The aim of this randomized, double-blind placebo-controlled pilot trial was to evaluate neurocognitive effects of memantine over a 24-week trial. Twenty-three children ages 6-12 years old with ASD were randomized to memantine or placebo. Primary outcomes included measures of apraxia and expressive language with evaluations at midpoint (week 12) and endpoint (week 24). Secondary outcomes included memory and adaptive behavior measures. Exploratory outcomes included changes in overall cognitive functioning and behavior (e.g., Aberrant Behavior Checklist). Results: Results suggest that memantine was well-tolerated. Dropout rates were high across groups with only 14 participants completing the 6-month trial. Memantine was not associated with improvements in apraxia and expressive language. Treatment with memantine was associated with improvements in verbal recognition memory as measured by the Narrative Memory-Recognition (NEPSY-II) (F = 5.05, p = .03). In addition, exploratory analyses of changes in Intelligence quotient (IQ) suggest improvements on verbal IQ (d = 1.8). Conclusions: Results suggest future studies of memantine in ASD may benefit from shifting treatment targets from social and behavioral outcomes to exploration of effects of memantine on cognition, potentially as an adjunct to learning and educational interventions. ClinicalTrials.gov: NCT01372449.

Examining a stepped-care telehealth program for parents of young children with autism: a proof-of-concept trial.

BACKGROUND: Intervention during the first years of life for children with autism spectrum disorder (ASD) may have the strongest impact on long-term brain development and functioning. Yet, barriers such as a shortage of trained professionals contribute to significant delays in service. The goal of this proof-of-concept study was to explore strategies that support timely and equitable deployment of ASD-specific interventions. METHODS: This 15-week, randomized proof-of-concept study explored the acceptability of a digital parent mediated intervention online reciprocal imitation training (RIT; a naturalistic developmental behavioral intervention) and compared it to a treatment as usual (TAU) control on parent and child outcomes. Eligible children were between 18 and 60 months, met the cutoff for ASD on the Autism Diagnostic Observation Schedule-2nd Edition and demonstrate significant social imitation deficits. Primary outcomes include the acceptability of RIT (Scale of Treatment Perceptions) and the feasibility of the Online RIT digital intervention (online RIT attributes). Secondary outcomes included parent fidelity (RIT parent fidelity form) and parental self-efficacy (Early Intervention Parenting Self-Efficacy Scale). Exploratory outcome measures included child social communication (Social Communication Checklist), child imitation skills (Unstructured Imitation Assessment), and family quality of life (Beach Center Family Quality of Life Scale). RESULTS: Twenty participants were randomized in a 1:1 fashion. The acceptability and feasibility of RIT and the Online RIT digital intervention were rated highly. Among the secondary outcomes, there were significant group differences in parent fidelity (p < .001) and self-efficacy (p = .029). On exploratory outcomes, there were group differences in child social communication (p = .048). There were no significant group differences in imitation ability (p = .05) or family quality of life (p = .22). LIMITATIONS: There are several limitations with this study, including the small sample size as well as lack of data on enactment and website engagement. This study was not able to address questions related to which variables predict program engagement and treatment response, which will be critical for determining which families may benefit from such a stepped-care delivery model. CONCLUSIONS: Overall, the Online RIT program delivered in a stepped-care format shows strong acceptability and holds promise as an innovative delivery model. Trial registration ClinicalTrials.gov, NCT04467073. Registered 10 July 2020- Retrospectively registered, https://clinicaltrials.gov/ct2/show/NCT04467073.

A novel measure of matching categories for early development: Item creation and pilot feasibility study.

BACKGROUND: Many cognitive tests assess a limited developmental span, making longitudinal measurement for trials aimed at improving cognition challenging. Tests targeting transitional skills, which integrate foundational abilities into complex schemas, may be amenable to assessment across a wide developmental span. Furthermore, tablet-based tests permit computer adaptive testing (CAT), which is psychometrically more efficient and could increase testing motivation, especially for children with developmental delays. Such measures may be useful for research and clinical practice. AIMS: Outline the creation of a novel, tablet-based concept formation test, and evaluate its feasibility in individuals with mental ages less than 24-months. METHODS AND PROCEDURES: Item generation, user interface construction, and pre-piloting were conducted in consultation with subject matter experts. Item content and interface parameters underwent iterative revisions, resulting in the pilot test. OUTCOMES AND RESULTS: We created and piloted a tablet-based test of concept formation suitable for CAT-based administration with items of increasing difficulty based on target salience. We show feasibility in individuals with mental ages less than 24-months-old. CONCLUSIONS AND IMPLICATIONS: Tablet-based assessment of concept formation may be a useful outcome measure of an aspect of cognitive ability in young children. Future work will address optimizing the user interface and developing CAT administration.

Prerequisite Skills in Cognitive Testing: Innovations in theory and recommendations for practice.

Testing cognitive skill development is important for diagnostic, prognostic, and monitoring purposes, especially for young children and individuals with neurodevelopmental disorders. Developmental tests have been created for infants and toddlers, while traditional IQ tests are often employed beginning in the later preschool period. However, IQ tests rely on developmental skills that are rapidly changing during early childhood. Here, we introduce the idea of prerequisite skills in developmental domains, which are discrete skills required for, but not explicitly tested by, traditional IQ tests. Focusing on general cognition, particularly among children with a chronological or mental age under 4 years, may fail to capture important nuances in skill development. New skill-based assessments are needed in general, and in particular for categorization, which is foundational to higher-order cognitive skills. Novel measures quantifying categorization skills would provide a more sensitive measure of development for young children and older individuals with low developmental levels.

Shifted phase of EEG cross-frequency coupling in individuals with Phelan-McDermid syndrome.

BACKGROUND: Phelan-McDermid Syndrome (PMS) is a rare condition caused by deletion or mutation of the SHANK3 gene. Individuals with PMS frequently present with intellectual disability, autism spectrum disorder, and other neurodevelopmental challenges. Electroencephalography (EEG) can provide a window into network-level function in PMS. METHODS: Here, we analyze EEG data collected across multiple sites in individuals with PMS (n = 26) and typically developing individuals (n = 15). We quantify oscillatory power, alpha-gamma phase-amplitude coupling strength, and phase bias, a measure of the phase of cross frequency coupling thought to reflect the balance of feedforward (bottom-up) and feedback (top-down) activity. RESULTS: We find individuals with PMS display increased alpha-gamma phase bias (U = 3.841, p < 0.0005), predominantly over posterior electrodes. Most individuals with PMS demonstrate positive overall phase bias while most typically developing individuals demonstrate negative overall phase bias. Among individuals with PMS, strength of alpha-gamma phase-amplitude coupling was associated with Sameness, Ritualistic, and Compulsive behaviors as measured by the Repetitive Behavior Scales-Revised (Beta = 0.545, p = 0.011). CONCLUSIONS: Increased phase bias suggests potential circuit-level mechanisms underlying phenotype in PMS, offering opportunities for back-translation of findings into animal models and targeting in clinical trials.

The Autism Palette: Combinations of Impairments Explain the Heterogeneity in ASD.

Autism spectrum disorder (ASD) is a heterogeneous neuropsychiatric condition traditionally defined by core symptoms in social behavior, speech/communication, repetitive behavior, and restricted interests. Beyond the core symptoms, autism has strong association with other disorders such as intellectual disability (ID), epilepsy, schizophrenia among many others. This paper outlines a theory of ASD with capacity to connect heterogeneous "core" symptoms, medical and psychiatric comorbidities as well as other etiological theories of autism in a unifying cognitive framework rooted in neuroscience and genetics. Cognition is embedded into an ever-developing structure modified by experiences, including the outcomes of environment influencing behaviors. The key constraint of cognition is that the brain can handle only 7±2 relevant variables at a time, whereas sensory variables, i.e., the number of sensory neurons is orders of magnitude larger. As a result, (a) the extraction, (b) the encoding, and (c) the capability for the efficient cognitive manipulation of the relevant variables, and (d) the compensatory mechanisms that counteract computational delays of the distributed components are critical. We outline our theoretical model to describe a Cartesian Factor (CF) forming, autoencoder-like cognitive mechanism which breaks combinatorial explosion and is accelerated by internal reinforcing machineries and discuss the neural processes that support CF formation. Impairments in any of these aspects may disrupt learning, cognitive manipulation, decisions on interactions, and execution of decisions. We suggest that social interactions are the most susceptible to combinations of diverse small impairments and can be spoiled in many ways that pile up. Comorbidity is experienced, if any of the many potential impairments is relatively strong. We consider component spoiling impairments as the basic colors of autism, whereas the combinations of individual impairments make the palette of autism. We put forth arguments on the possibility of dissociating the different main elements of the impairments that can appear together. For example, impairments of generalization (domain general learning) and impairments of dealing with many variable problems, such as social situations may appear independently and may mutually enhance their impacts. We also consider mechanisms that may lead to protection.

Psychometric Study of the Social Responsiveness Scale in Phelan-McDermid Syndrome.

The Social Responsiveness Scale-2 (SRS-2) is a quantitative measure used to characterize symptoms of autism spectrum disorder (ASD). However, research suggests that SRS-2 scores are significantly influenced by language ability and intellectual disability (ID). Efforts to refine the SRS-2 by Sturm, Kuhfeld, Kasari, and Mccracken [Journal of Child Psychology and Psychiatry, 58(9), 1053-1061] yielded a shortened form, yet its psychometric properties in populations with severe ID remain unknown. This study aims to examine the psychometric properties of the SRS-2 in Phelan-McDermid syndrome (PMS), a genetic condition associated with ASD and ID, thereby guiding score interpretation in this population and future development of targeted scales. Analyses, including Item Response Theory (IRT), were conducted on a sample of individuals with PMS (n = 91) recruited at six sites nationally. Psychometric properties evaluated include measures of reliability (internal consistency, test-retest reliability) and validity (structural, construct, content). While both SRS-2 forms are reliable, the shortened SRS-2 shows superior validity to the full SRS-2 for measuring ASD symptoms in PMS. On IRT analysis, the shortened SRS-2 shows excellent discrimination and precisely evaluates respondents across a wide range of ASD symptomatology but interpretation is limited by uncertain content validity and small sample size. The shortened SRS-2 shows some promise for use in PMS, but future refinements and additions are needed to develop items that are tailored to identify ASD in children with severe ID and specifically PMS. LAY SUMMARY: This study determined that a shortened form of the Social Responsiveness Scale, Second Edition (SRS-2) shows both promise and limitations for the characterization of autism symptomatology in individuals with Phelan-McDermid syndrome (PMS), a population characterized by intellectual disability (ID). Caution should be used when interpreting SRS-2 scores in individuals with ID and future research should modify existing items and develop new items to improve the SRS-2's ability to accurately characterize autism symptomatology in PMS. Autism Res 2020, 13: 1383-1396. © 2020 International Society for Autism Research, Wiley Periodicals, Inc.

Diffusion Tensor Imaging Abnormalities in the Uncinate Fasciculus and Inferior Longitudinal Fasciculus in Phelan-McDermid Syndrome.

BACKGROUND: This cohort study utilized diffusion tensor imaging tractography to compare the uncinate fasciculus and inferior longitudinal fasciculus in children with Phelan-McDermid syndrome with age-matched controls and investigated trends between autism spectrum diagnosis and the integrity of the uncinate fasciculus and inferior longitudinal fasciculus white matter tracts. METHODS: This research was conducted under a longitudinal study that aims to map the genotype, phenotype, and natural history of Phelan-McDermid syndrome and identify biomarkers using neuroimaging (ClinicalTrial NCT02461420). Patients were aged three to 21 years and underwent longitudinal neuropsychologic assessment over 24 months. MRI processing and analyses were completed using previously validated image analysis software distributed as the Computational Radiology Kit (http://crl.med.harvard.edu/). Whole-brain connectivity was generated for each subject using a stochastic streamline tractography algorithm, and automatically defined regions of interest were used to map the uncinate fasciculus and inferior longitudinal fasciculus. RESULTS: There were 10 participants (50% male; mean age 11.17 years) with Phelan-McDermid syndrome (n = 8 with autism). Age-matched controls, enrolled in a separate longitudinal study (NIH R01 NS079788), underwent the same neuroimaging protocol. There was a statistically significant decrease in the uncinate fasciculus fractional anisotropy measure and a statistically significant increase in uncinate fasciculus mean diffusivity measure, in the patient group versus controls in both right and left tracts (P ≤ 0.024). CONCLUSION: Because the uncinate fasciculus plays a critical role in social and emotional interaction, this tract may underlie some deficits seen in the Phelan-McDermid syndrome population. These findings need to be replicated in a larger cohort.

A Multisite, Multidisciplinary Delphi Consensus Study Describing "Usual Care" Intervention Strategies for School-Age to Transition-Age Youth With Autism.

Understanding usual care is important to reduce health disparities and improve the dissemination of evidence-based practices for youth (ages 7-22 years) with autism spectrum disorder (ASD). A barrier to describing "usual ASD care" is the lack of a common vocabulary and inventory of the practices used by a diverse provider field. To address this barrier, we gathered input from expert providers to develop an inventory of usual care practices and assess expert familiarity and perceptions of these practices as interventions for anxiety, externalizing, and social difficulties in ASD. Purposeful sampling recruited 66 expert ASD providers representing multiple disciplines from 5 sites. Via a 2-round Delphi poll, experts reviewed, suggested revisions to and rated 49 literature-derived practices on several dimensions (familiarity, usefulness, common use, research support). A revised list of 55 practices and anonymous summary of group characteristics and ratings was then returned for further review. Results yielded 55 intervention practices, 48 of which were identified as "familiar" approaches by consensus (≥ 75% endorsement). Greater variation was observed in practices identified by consensus as most often used, useful, and research supported, depending upon the target problem. Findings provide an inventory of practices, reflective of the multidisciplinary language and approaches of expert ASD providers. This inventory may be used to better assess what constitutes usual care for youth with ASD in the United States. Moreover, findings offer insights from clinical experts regarding the range and acceptability of practices that may inform and ground treatment research, dissemination, and implementation efforts.