1. Granovetter MC, Burlingham CS, Blauch NM, Minshew NJ, Heeger DJ, Behrmann M. {{Uncharacteristic task-evoked pupillary responses implicate atypical locus coeruleus activity in autism}}. {J Neurosci}. 2020.
Autism spectrum disorder (ASD) is characterized partly by atypical attentional engagement, reflected in exaggerated and variable responses to sensory stimuli. Attentional engagement is known to be regulated by the locus coeruleus (LC). Moderate baseline LC activity globally dampens neural responsivity and is associated with adaptive deployment and narrowing of attention to task-relevant stimuli. In contrast, increased baseline LC activity enhances neural responsivity across cortex and widening of attention to environmental stimuli regardless of their task relevance. Given attentional atypicalities in ASD, this study is the first to evaluate whether, under different attentional task demands, individuals with ASD exhibit a different profile of LC activity compared to typically developing controls. Males and females with ASD and age- and gender-matched controls participated in a one-back letter detection test while task-evoked pupillary responses-an established correlate for LC activity-were recorded. Participants completed this task in two conditions, either in the absence or presence of distractor auditory tones. Compared to controls, individuals with ASD evinced atypical pupillary responses in the presence versus absence of distractors. Notably, this atypical pupillary profile was evident despite the fact that both groups exhibited equivalent task performance. Moreover, between-group differences in pupillary responses were observed specifically in response to task-relevant events, providing confirmation that the group differences most likely were specifically associated with distinctions in LC activity. These findings suggest that individuals with ASD show atypical modulation of LC activity with changes in attentional demands, offering a possible mechanistic and neurobiological account for attentional atypicalities in ASD.Significance StatementIndividuals with autism spectrum disorder (ASD) exhibit atypical attentional behaviors, including altered sensory responses and atypical fixedness, but the neural mechanism underlying these behaviors remains elusive. One candidate mechanism is atypical locus coeruleus (LC) activity, as the LC plays a critical role in attentional modulation. Specifically, LC activity is involved in regulating the tradeoff between environmental exploration and focused attention. This study shows that, under tightly controlled conditions, task-evoked pupil responses-an LC activity proxy-are lower in individuals with ASD than in controls, but only in the presence of task-irrelevant stimuli. This suggests that individuals with ASD evince atypical modulation of LC activity in accordance with changes in attentional demands, offering a mechanistic account for attentional atypicalities in ASD.
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2. Jin P, Wang Y, Li Y, Xiao Y, Li C, Qiu N, Weng J, Fang H, Ke X. {{The fair decision-making of children and adolescents with high-functioning autism spectrum disorder from the perspective of dual-process theories}}. {BMC Psychiatry}. 2020; 20(1): 152.
BACKGROUND: Fairness has received much attention in our society. At present, the findings regarding fair decision-making in high-functioning autism spectrum disorder (HF-ASD) are inconsistent. Previous studies have shown that the fair decision-making of typically developing children is influenced by theory of mind (ToM) and executive functioning (EF). As those with HF-ASD have defects in both domains, this study aims to explore the differences in fair decision-making between children and adolescents with HF-ASD and those with typical development (TD). METHODS: We used a simple ultimatum game (UG) to explore 31 children and adolescents with HF-ASD and 38 children and adolescents with TD. T tests and chi-square tests were used to compare group differences, and Pearson correlation analysis and stepwise regression analysis were used to analyse the mechanisms influencing the two groups’ unfair acceptance rates. RESULTS: The results show that children with HF-ASD are more likely to accept unfair offers, but for adolescents, the difference is not significant. Regression analysis showed that the interaction between the behavior regulation index (BRI) and age could negatively predict the unfair acceptance rate of children and adolescents with HF-ASD. Working memory and ToM can negatively predict the unfair acceptance rate of those with TD. CONCLUSION: This study concluded that the development of fair decision-making by children and adolescents with HF-ASD falls far behind that of those with TD. Intuition processes play a dominant role in the fair decision-making processes of children and adolescents with HF-ASD, and we believe that comorbidity, age, experience and emotional management are important factors influencing the fair decision-making of individuals with HF-ASD.
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3. Katz J, Knight V, Mercer SH, Skinner SY. {{Effects of a Universal School-Based Mental Health Program on the Self-concept, Coping Skills, and Perceptions of Social Support of Students with Developmental Disabilities}}. {J Autism Dev Disord}. 2020.
In a cluster randomized control trial, a school-based mental health program combining mental health literacy and dialectical behavior skills was implemented by teachers to determine effects on protective factors related to resilience for students in 3rd-12th grade. As part of a larger study, a subsample of 113 students with developmental disabilities attending 37 classrooms participated. Student-reported measures of self-concept, coping skills, and social support were collected three times in the year. Results indicated large effect sizes for the program on all measures, which pertain to time x group interactions (g = 1.53, 1.91, and 0.86 for self-concept, coping, and social support respectively). Follow-up analyses indicated that gains for the intervention schools primarily occurred between the first two assessment periods when the majority of program content was delivered. Implications for universal school-based mental health programming for students with developmental disabilities are discussed.
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4. Lee YS, Yu NK, Chun J, Yang JE, Lim CS, Kim H, Park G, Lee JA, Lee K, Kaang BK, Lee JH. {{Identification of a novel Shank2 transcriptional variant in Shank2 knockout mouse model of autism spectrum disorder}}. {Molecular brain}. 2020; 13(1): 54.
Autism spectrum disorder (ASD) is a group of neurodevelopmental disorders that are highly heterogeneous in clinical symptoms as well as etiologies. Mutations in SHANK2 are associated with ASD and accordingly, Shank2 knockout mouse shows ASD-like behavioral phenotypes, including social deficits. Intriguingly, two lines of Shank2 knockout (KO) mouse generated by deleting different exons (exon 6-7 or exon 7) showed distinct cellular phenotypes. Previously, we compared gene expressions between Shank2 KOs lacking exon 6-7 (e6-7 KO) and KOs lacking exon 7 (e7 KO) by performing RNA-seq. In this study, we expanded transcriptomic analyses to identify novel transcriptional variants in the KO mice. We found prominent expression of a novel exon (exon 4′ or e4′) between the existing exons 4 and 5 in the Shank2 e6-7 KO model. Expression of the transcriptional variant harboring this novel exon was confirmed by RT-PCR and western blotting. These findings suggest that the novel variant may function as a modifier gene, which contributes to the differences between the two Shank2 mutant lines. Furthermore, our result further represents an example of genetic compensation that may lead to phenotypic heterogeneity among ASD patients with mutations in the same gene.
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5. Lopez K, Marroquin JM, Gutierrez C. {{Methods to Decrease Disparities in Age of Autism Diagnosis and Treatment Access among Latinx Children}}. {Social work}. 2020.
Autism spectrum disorder (ASD) affects a substantial number of individuals and their families. Early diagnosis followed by intensive behavioral services is critical to reducing social communication deficits and behavioral challenges. Research has continually demonstrated health disparities with Latinx families that perpetuate lower ASD prevalence rates, later ASD diagnosis, and limited access to treatment compared with white children. Moreover, Latinx children who are diagnosed with ASD receive less intense and fewer treatment services. Given the number of Latinx children and those with ASD, social workers are likely to encounter the intersection throughout their careers. Thus, it is critical for social workers to have general knowledge about autism and the complexity of accessing diagnostic and treatment services. In this article, the authors review the literature on Latinx children and ASD, and identify opportunities for social workers to be innovative in their use of frameworks, theories, and practice approaches to reduce disparities in ASD diagnosis and treatment among Latinx children.
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6. Peters BC, Wood W, Hepburn S, Bundy A. {{Pilot Study: Occupational Therapy in an Equine Environment for Youth With Autism}}. {OTJR : occupation, participation and health}. 2020: 1539449220912723.
Despite growing prevalence, research investigating occupational therapy incorporating horses for youth with autism is limited. This study aimed to (a) pilot a screening, evaluation, and intervention protocol of occupational therapy in an equine environment and (b) assess preliminary effects on occupational performance goals, behavior, and social functioning of youth with autism. A multiple baseline single-case experimental design was used. Six youth with autism participated in a no-treatment baseline phase and 10 weeks of intervention. Therapists implemented the intervention with 95% fidelity. Per parent report, participants improved in occupational performance goals, social motivation, and communication; four demonstrated decreased irritability and hyperactivity. This research operationalizes a screening, evaluation, and intervention protocol for occupational therapy in an equine environment, and demonstrates it may improve occupational, behavioral, and social outcomes for youth with autism. Next steps include manualizing the intervention, refining feasibility measures, and implementing a randomized controlled efficacy study.
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7. Sarmukadam K, Bitsika V, Sharpley CF, McMillan MME, Agnew LL. {{Comparing different EEG connectivity methods in young males with ASD}}. {Behav Brain Res}. 2020; 383: 112482.
Although EEG connectivity data are often used to build models of the association between overt behavioural signs of Autism Spectrum Disorder (ASD) and underlying brain connectivity indices, use of a large number of possible connectivity methods across studies has produced a fairly inconsistent set of results regarding this association. To explore the level of agreement between results from five commonly-used EEG connectivity models (i.e., Coherence, Weighted Phased Lag Index- Debiased, Phase Locking Value, Phase Slope Index, Granger Causality), a sample of 41 young males with ASD provided EEG data under eyes-opened and eyes-closed conditions. There were relatively few statistically significant and/or meaningful correlations between the results obtained from the five connectivity methods, arguing for a re-estimation of the methodology used in such studies so that specific connectivity methods may be matched to particular research questions regarding the links between neural connectivity and overt behaviour within this population.
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8. Slaughter AM, Hein S, Hong JH, Mire SS, Grigorenko EL. {{Correction to: Criminal Behavior and School Discipline in Juvenile Justice-Involved Youth with Autism}}. {J Autism Dev Disord}. 2020.
The original version of the article has unfortunately contained formatting errors in tables.
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9. Walker SC, Williams K, Moore DJ. {{Superior identification of component odours in a mixture is linked to autistic traits in children and adults}}. {Chemical senses}. 2020.
Most familiar odours are complex mixtures of volatile molecules which the olfactory system automatically synthesises into a perceptual whole. However, odours are rarely encountered in isolation, thus the brain must also separate distinct odour objects from complex and variable backgrounds. In vision, autistic traits are associated with superior performance in tasks that require focus on the local features of a perceptual scene. The aim of the present study was to determine whether the same advantage was observed in the analysis of olfactory scenes. To do this, we compared the ability of (i) Forty young adults (aged 16-35) with high (n=20) and low levels of autistic traits and, (ii) Twenty children (aged 7-11), with (n=10) and without an autism spectrum disorder diagnosis, to identify individual odour objects presented within odour mixtures. First, we used a 4-alternative forced choice task to confirm both adults and children were able to reliably identify eight blended fragrances, representing food related odours, when presented individually. We then used the same forced-choice format to test participants’ ability to identify the odours when they were combined in either binary or ternary mixtures. Adults with high levels of autistic traits showed superior performance on binary but not ternary mixture trials. While children with an autism spectrum disorder diagnosis outperformed age matched neurotypical peers, irrespective of mixture complexity. These findings indicate, the local processing advantages associated with high levels of autistic traits in visual tasks are also apparent in a task requiring analytical processing of odour mixtures.
