1. Ahammed MS, Niu S, Ahmed MR, Dong J, Gao X, Chen Y. DarkASDNet: Classification of ASD on Functional MRI Using Deep Neural Network. Frontiers in neuroinformatics. 2021; 15: 635657.

Non-invasive whole-brain scans aid the diagnosis of neuropsychiatric disorder diseases such as autism, dementia, and brain cancer. The assessable analysis for autism spectrum disorders (ASD) is rationally challenging due to the limitations of publicly available datasets. For diagnostic or prognostic tools, functional Magnetic Resonance Imaging (fMRI) exposed affirmation to the biomarkers in neuroimaging research because of fMRI pickup inherent connectivity between the brain and regions. There are profound studies in ASD with introducing machine learning or deep learning methods that have manifested advanced steps for ASD predictions based on fMRI data. However, utmost antecedent models have an inadequacy in their capacity to manipulate performance metrics such as accuracy, precision, recall, and F1-score. To overcome these problems, we proposed an avant-garde DarkASDNet, which has the competence to extract features from a lower level to a higher level and bring out promising results. In this work, we considered 3D fMRI data to predict binary classification between ASD and typical control (TC). Firstly, we pre-processed the 3D fMRI data by adopting proper slice time correction and normalization. Then, we introduced a novel DarkASDNet which surpassed the benchmark accuracy for the classification of ASD. Our model’s outcomes unveil that our proposed method established state-of-the-art accuracy of 94.70% to classify ASD vs. TC in ABIDE-I, NYU dataset. Finally, we contemplated our model by performing evaluation metrics including precision, recall, F1-score, ROC curve, and AUC score, and legitimize by distinguishing with recent literature descriptions to vindicate our outcomes. The proposed DarkASDNet architecture provides a novel benchmark approach for ASD classification using fMRI processed data.

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2. Bertrams A, Zäch M. Autistic Traits Predict Social-Contact Uncertainty in University Students. Frontiers in psychiatry. 2021; 12: 572445.

Social anxiety (alternatively: social-contact uncertainty) in the university context can lead to reduced health, well-being, and performance, and can even cause premature leaving of education. With the present study, we intended to supplement cross-sectional studies on students’ autistic traits and social anxiety with longitudinal findings. We measured autistic traits and social-contact uncertainty of 118 university students on two occasions, roughly 1 year apart. Correlation, multiple regression, and cross-lagged analyses showed that more pronounced autistic traits predicted higher future social-contact uncertainty. Social-contact uncertainty did not predict autistic traits. We conclude that university students who are high in autistic traits tend not only to be more socially anxious at the moment but have a heightened risk of still being so in the future.

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3. Chien YL, Tsai WC, Chen WH, Yang CL, Gau SS, Soong WT, Laugeson E, Chiu YN. Effectiveness, durability, and clinical correlates of the PEERS social skills intervention in young adults with autism spectrum disorder: the first evidence outside North America. Psychological medicine. 2021: 1-11.

BACKGROUND: Despite the fact that social deficits among individuals with autism spectrum disorder (ASD) are lifelong and impact many aspects of personal functioning, evidence-based programs for social skills training were not available until recently. The Program for the Education and Enrichment of Relational Skills (PEERS®) has been shown to effectively improve social skills for adolescents on the spectrum across different social cultures. However, the effectiveness for young adults beyond North America has yet to be examined. This study aimed to investigate the effectiveness of the PEERS intervention in Taiwanese young adults with ASD, and examine its durability and clinical correlates. METHODS: We recruited 82 cognitively-able young adults with ASD, randomized to the PEERS treatment or treatment-as-usual. RESULTS: Following treatment, significant improvement was found in aspects of social deficits, autism severity, social interaction anxiety, empathy, and social skills knowledge either by self-report or coach-report. Additionally, communicative behaviors rated by observers improved throughout the sessions, showing a trend toward more appropriate eye contact, gestures, facial expression during conversation, and appropriate maintenance of conversation and reciprocity. Most effects maintained at 3-month and 6-month follow-ups. The improvement of social deficits was positively correlated with baseline severity, while gains in social skills knowledge were positively correlated with IQ. The improvement of social deficits, autism severity, and empathy were positively correlated with each other. CONCLUSION: Overall, the PEERS intervention appears to effectively improve social functioning in Taiwanese young adults with ASD. Improvement of social response and knowledge may be predicted by baseline severity and intelligence respectively.

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4. Davis DN, Strong MD, Chambers E, Hart MD, Bettaieb A, Clarke SL, Smith BJ, Stoecker BJ, Lucas EA, Lin D, Chowanadisai W. A role for zinc transporter gene SLC39A12 in the nervous system and beyond. Gene. 2021; 799: 145824.

The SLC39A12 gene encodes the zinc transporter protein ZIP12, which is expressed across many tissues and is highly abundant in the vertebrate nervous system. As a zinc transporter, ZIP12 functions to transport zinc across cellular membranes, including cellular zinc influx across the plasma membrane. Genome-wide association and exome sequencing studies have shown that brain susceptibility-weighted magnetic resonance imaging (MRI) intensity is associated with ZIP12 polymorphisms and rare mutations. ZIP12 is required for neural tube closure and embryonic development in Xenopus tropicalis. Frog embryos depleted of ZIP12 by antisense morpholinos develop an anterior neural tube defect and lack viability. ZIP12 is also necessary for neurite outgrowth and mitochondrial function in mouse neural cells. ZIP12 mRNA is increased in brain regions of schizophrenic patients. Outside of the nervous system, hypoxia induces ZIP12 expression in multiple mammalian species, including humans, which leads to endothelial and smooth muscle thickening in the lung and contributes towards pulmonary hypertension. Other studies have associated ZIP12 with other diseases such as cancer. Given that ZIP12 is highly expressed in the brain and that susceptibility-weighted MRI is associated with brain metal content, ZIP12 may affect neurological diseases and psychiatric illnesses such as Parkinson’s disease, Alzheimer’s disease, and schizophrenia. Furthermore, the induction of ZIP12 and resultant zinc uptake under pathophysiological conditions may be a critical component of disease pathology, such as in pulmonary hypertension. Drug compounds that bind metals like zinc may be able to treat diseases associated with impaired zinc homeostasis and altered ZIP12 function.

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5. Giona F, Pagano J, Verpelli C, Sala C. Another step toward understanding brain functional connectivity alterations in autism: An Editorial Highlight for « Neurobiological substrates underlying corpus callosum hypoconnectivity and brain metabolic patterns in the valproic acid rat model of autism spectrum disorder » on page 128. Journal of neurochemistry. 2021; 159(1): 12-4.

Various neuroimaging approaches have reported alterations in brain connectivity in patients with autism spectrum disorder (ASD). Nevertheless, specific cellular and molecular mechanisms underlying these alterations remain to be elucidated. In the present Editorial, we highlight an article in the current issue of the Journal of Neurochemistry that provides first evidence for the structural and cellular basis of an atypical corpus callosum long-distance connectivity impairments observed in ASD patients. The authors used a juvenile valproic acid (VPA) rat model of ASD that presents with reduced myelin level, specifically in the corpus callosum, and with an altered myelin sheet structure that is closely associated with the behavioral alteration found in these rats. This hypomyelination occurs primarily during infancy prior to oligodendroglial alterations, implicating that axonal-oligodendroglial connections are compromised in this model. Concomitant with the hypomyelination, the ASD rat model showed an atypical brain metabolic pattern, with hypometabolic activity across the whole brain, and hypermetabolism in brain areas related to autistic-like behavior. These findings contribute to unravel the neurobiological basis underlying white matter alteration and altered long-distance brain connectivity as described in ASD, paving the way to the development of new early diagnostic markers and toward developing future specific therapies for ASD.

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6. Howell M, Bailey T, Bradshaw J, Langdon PE. The preliminary validity and reliability of the Assessment of Barriers to Learning in Education – Autism. Research in developmental disabilities. 2021; 116: 104025.

BACKGROUND: Few robust autism-specific outcome assessments have been developed specifically for use by teachers in special schools. The Assessment of Barriers to Learning in Education – Autism (ABLE-Autism) is a newly developed teacher assessment to identify and show progress in barriers to learning for pupils on the autism spectrum with coexisting intellectual disabilities. AIMS: This study aimed to conduct a preliminary validity and reliability evaluation of the ABLE-Autism. METHODS AND PROCEDURES: Forty-eight autistic pupils attending special schools were assessed using the ABLE-Autism. Multi-level modelling was used to evaluate test-retest reliability, internal consistency and convergent validity with the Teacher Autism Progress Scale. OUTCOMES AND RESULTS: Results showed excellent test-retest reliability and internal consistency. A large effect size suggested that the ABLE-Autism is strongly correlated with the Teacher Autism Progress Scale. Teacher feedback was positive and suggested that the ABLE-Autism is easily understood by teachers, relevant to autistic pupils in special schools, and adequately covers the skills and behaviours that teachers believe are important to assess for these pupils. CONCLUSIONS AND IMPLICATIONS: Although further validation is recommended, the preliminary evaluation of the ABLE-Autism suggests that it is a useful and has the potential to be an effective outcome assessment for autistic pupils in special schools.

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7. Karami B, Koushki R, Arabgol F, Rahmani M, Vahabie AH. Effectiveness of Virtual/Augmented Reality-Based Therapeutic Interventions on Individuals With Autism Spectrum Disorder: A Comprehensive Meta-Analysis. Frontiers in psychiatry. 2021; 12: 665326.

In recent years, the application of virtual reality (VR) for therapeutic purposes has escalated dramatically. Favorable properties of VR for engaging patients with autism, in particular, have motivated an enormous body of investigations targeting autism-related disabilities with this technology. This study aims to provide a comprehensive meta-analysis for evaluating the effectiveness of VR on the rehabilitation and training of individuals diagnosed with an autism spectrum disorder. Accordingly, we conducted a systematic search of related databases and, after screening for inclusion criteria, reviewed 33 studies for more detailed analysis. Results revealed that individuals undergoing VR training have remarkable improvements with a relatively large effect size with Hedges g of 0.74. Furthermore, the results of the analysis of different skills indicated diverse effectiveness. The strongest effect was observed for daily living skills (g = 1.15). This effect was moderate for other skills: g = 0.45 for cognitive skills, g = 0.46 for emotion regulation and recognition skills, and g = 0.69 for social and communication skills. Moreover, five studies that had used augmented reality also showed promising efficacy (g = 0.92) that calls for more research on this tool. In conclusion, the application of VR-based settings in clinical practice is highly encouraged, although their standardization and customization need more research.

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8. Mandic-Maravic V, Mitkovic-Voncina M, Pljesa-Ercegovac M, Savic-Radojevic A, Djordjevic M, Ercegovac M, Pekmezovic T, Simic T, Pejovic-Milovancevic M. Glutathione S-Transferase Polymorphisms and Clinical Characteristics in Autism Spectrum Disorders. Frontiers in psychiatry. 2021; 12: 672389.

Background: Autism spectrum disorders (ASD) are a heterogeneous group of developmental disorders, with different levels of symptoms, functioning, and comorbidities. Recent findings suggested that oxidative stress and genetic variability in glutathione S-transferases (GSTs) might increase the risk of ASD development. We aimed to determine whether GST polymorphisms influence the severity of symptoms as well as the cognitive and adaptive abilities in children with ASD. Methods: The sample included 113 ASD cases. All participants were genotyped for GSTA1, GSTM1, GSTT1, and GSTP1 polymorphisms. The clinical characteristics were determined with Autism Diagnostic Interview-Revised (ADI-R) in all of the participants. In non-verbal participants, we explored the adaptive functioning using the Vineland Adaptive Behavior Scale II, while in verbal participants, we used the Wechsler Abbreviated Scale of Intelligence (WASI). Results: It was shown that the GSTA1 (*) CC genotype was a predictor of a lower non-verbal communication impairment as well as of a lower chance of having seizures during life. GSTM1-active genotype predicted a higher adaptive functioning. The predictive effect of GSTA1, GSTM1, and GSTT1 genotype was moderated by exposure during pregnancy (maternal smoking and medication). The GSTP1 (*) IleIle genotype was significantly associated to a better cognitive functioning in children with ASD. Conclusion: Besides the complex gene-environment interaction for the specific risk of developing ASD, there is also a possible complexity of interactions between genetic and environmental factors influencing the level of symptoms and impairment in people with ASD. Detoxification and antioxidant enzymes, such as GSTA1, might contribute to the core of this complexity.

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9. Nguyen QA, Rubchinsky LL. Temporal patterns of synchrony in a pyramidal-interneuron gamma (PING) network. Chaos (Woodbury, NY). 2021; 31(4): 043134.

Synchronization in neural systems plays an important role in many brain functions. Synchronization in the gamma frequency band (30-100 Hz) is involved in a variety of cognitive phenomena; abnormalities of the gamma synchronization are found in schizophrenia and autism spectrum disorder. Frequently, the strength of synchronization is not high, and synchronization is intermittent even on short time scales (few cycles of oscillations). That is, the network exhibits intervals of synchronization followed by intervals of desynchronization. Neural circuit dynamics may show different distributions of desynchronization durations even if the synchronization strength is fixed. We use a conductance-based neural network exhibiting pyramidal-interneuron gamma rhythm to study the temporal patterning of synchronized neural oscillations. We found that changes in the synaptic strength (as well as changes in the membrane kinetics) can alter the temporal patterning of synchrony. Moreover, we found that the changes in the temporal pattern of synchrony may be independent of the changes in the average synchrony strength. Even though the temporal patterning may vary, there is a tendency for dynamics with short (although potentially numerous) desynchronizations, similar to what was observed in experimental studies of neural synchronization in the brain. Recent studies suggested that the short desynchronizations dynamics may facilitate the formation and the breakup of transient neural assemblies. Thus, the results of this study suggest that changes of synaptic strength may alter the temporal patterning of the gamma synchronization as to make the neural networks more efficient in the formation of neural assemblies and the facilitation of cognitive phenomena.

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10. Praus P, Bilek E, Holz NE, Braun U. [The domain « social processes » in the system of research domain criteria: current state and perspectives]. Der Nervenarzt. 2021; 92(9): 925-32.

Social processes and their dysfunction, e.g. in autism spectrum disorders and psychotic disorders, have always been at the core of psychiatry. The last decades have led to impressive advances in our understanding of the underlying neurobiological mechanisms and also in the way we study and analyze social processes. Since their establishment, the research domain criteria have provided a powerful framework of how to operationalize and subdivide complex social processes in a way that it closely aligns to underlying neurobiological substrates while still enabling clinical approaches. In this article we summarize and discuss the most important findings for each of the four fundamental constructs of the social processes domain (a) binding and attachment, (b) social communication, (c) perception and understanding of self and (d) perception and understanding of others. We highlight the clinical relevance of the insights generated by the field of social neurosciences and discuss the resulting increasing importance of transdiagnostic concepts in applied research. Finally, we showcase three innovative research methods that build on the accelerating technological advances of the last decade and which will increasingly enable the study of complex social interactions in more realistic and ecologically valid settings.

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11. Rocos B, Zeller R. Correcting Scoliosis in Rett Syndrome. Cureus. 2021; 13(6): e15411.

Objectives Rett syndrome is a rare disorder characterised by severe scoliosis in 80% of cases. In this retrospective case series, we analysed the radiographic, clinical, and functional outcomes of consecutive patients treated for scoliosis associated with Rett syndrome. We sought to understand the results of the treatment of scoliosis in Rett syndrome and evaluate the need to fuse to the pelvis. Methods A retrospective case series was used to analyse the radiographic, clinical, and functional outcomes of consecutive patients treated for Rett syndrome scoliosis between the ages of 10 and 8 years in a single tertiary paediatric spinal unit. Cases were identified through departmental and neurophysiological records, and patients were excluded if the diagnosis of Rett syndrome was not confirmed. Results Seven eligible cases were identified. At presentation, the mean coronal Cobb angle was 90.9°, mean sagittal Cobb 72.0°, and pelvic obliquity 24.5°. The mean post-operative improvement in coronal Cobb was 53.2° and pelvic obliquity reduced to 5.8°. These did not change during a mean follow up of 3.5 years. None showed any post-operative complications. Three patients with a mean 16.1° pelvic obliquity underwent a fusion to L5. The postoperative result in those cases remained stable at 3.5 years mean follow-up and full skeletal maturity. Conclusion Our data suggests that with modern technology, severe curves can be safely treated. Fusion to the pelvis is not necessary in patients with mild, flexible pelvic obliquity.

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12. Salters D, Rios PC, Scharoun Benson SM. Instructors’ Perspectives of Social and Motor Influences on Participation in Children With Autism Spectrum Disorder. Research quarterly for exercise and sport. 2021: 1-12.

Participation is key to childhood development and is essential for health and well-being; yet children with Autism Spectrum Disorder (ASD) participate less in social and physical activities compared to their typically developing peers and little is known about how social and motor challenges impact participation patterns. Purpose: The current research garnered experiential insights of the quality and quantity of participation, through the lens of instructors (N = 9) working with a child or children with ASD. Method: Semi-structured qualitative interviews were conducted to capture a comprehensive and informative profile of how social and motor functioning of children with ASD influence involvement in social and physical activities. Results: Thematic analysis revealed consistent viewpoints in four main areas: (1) Viewpoints extend beyond the World Health Organization definition of participation; (2) Participation depends on who is involved; (3) Although motivation, confidence, and competence in social/motor domains underlie participation, social challenges were perceived as the greatest barrier; (4) While acknowledging the benefits of participation, it is necessary to be cognizant of the required supports. Throughout these themes, the notion of heterogeneity was made very clear. Conclusion: Collectively, perspectives offer descriptive insight which may be useful when designing opportunities for participation in social and physical activities among children with ASD.

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13. Shea LL, Koffer Miller KH, Verstreate K, Tao S, Mandell D. States’ use of Medicaid to meet the needs of autistic individuals. Health services research. 2021; 56(6): 1207-14.

OBJECTIVE: To assess the use of Medicaid programs, including waivers, to address the needs of aging autistic individuals. DATA SOURCES: We gathered data on Medicaid programs in place between 2004 and 2015 for 50 states and the District of Columbia from the Centers for Medicare and Medicaid Services website, by contacting state Medicaid administrators and advocacy groups, and by reviewing the Medicaid Analytic eXtract Waiver Crosswalk. STUDY DESIGN: This retrospective analysis classified each Medicaid program and documented state changes over time in eligibility criteria: those serving autism spectrum disorder only, autism spectrum disorder or intellectual disability, and intellectual disability only. DATA COLLECTION/EXTRACTION METHODS: We captured age and diagnosis eligibility criteria for Medicaid programs serving any of the three target groups. PRINCIPAL FINDINGS: A total of 269 Medicaid programs met our criteria and most programs (51%) were 1915(c) waivers. The number of autism-specific 1915(c) waivers grew more than fivefold during the study period, outpacing increases in waivers serving individuals with intellectual disability. CONCLUSIONS: States varied in their use of Medicaid to address the needs of the aging autism population. Further study of characteristics of states that changed their Medicaid programs, and of the health care use and outcomes associated with these changes, are needed to identify opportunities to replicate effective approaches to meeting the needs of this population.

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14. Surgent O, Dean DC, Alexander AL, Dadalko OI, Guerrero-Gonzalez J, Taylor D, Skaletski E, Travers BG. Neurobiological and behavioural outcomes of biofeedback-based training in autism: a randomized controlled trial. Brain communications. 2021; 3(3): fcab112.

The human brain has demonstrated the power to structurally change as a result of movement-based interventions. However, it is unclear whether these structural brain changes differ in autistic individuals compared to non-autistic individuals. The purpose of the present study was to pilot a randomized controlled trial to investigate brain, balance, autism symptom severity and daily living skill changes that result from a biofeedback-based balance intervention in autistic adolescents (13-17 years old). Thirty-four autistic participants and 28 age-matched non-autistic participants underwent diagnostic testing and pre-training assessment (neuroimaging, cognitive, autism symptom severity and motor assessments) and were then randomly assigned to 6 weeks of a balance-training intervention or a sedentary-control condition. After the 6 weeks, neuroimaging, symptom severity and motor assessments were repeated. Results found that both the autistic and non-autistic participants demonstrated similar and significant increases in balance times with training. Furthermore, individuals in the balance-training condition showed significantly greater improvements in postural sway and reductions in autism symptom severity compared to individuals in the control condition. Daily living scores did not change with training, nor did we observe hypothesized changes to the microstructural properties of the corticospinal tract. However, follow-up voxel-based analyses found a wide range of balance-related structures that showed changes across the brain. Many of these brain changes were specific to the autistic participants compared to the non-autistic participants, suggesting distinct structural neuroplasticity in response to balance training in autistic participants. Altogether, these findings suggest that biofeedback-based balance training may target postural stability challenges, reduce core autism symptoms and influence neurobiological change. Future research is encouraged to examine the superior cerebellar peduncle in response to balance training and symptom severity changes in autistic individuals, as the current study produced overlapping findings in this brain region.

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15. Talcer MC, Duffy O, Pedlow K. A Qualitative Exploration into the Sensory Experiences of Autistic Mothers. Journal of autism and developmental disorders. 2021.

Research has found 96% of autistic individuals experience sensory processing difficulties, and being a parent presents many sensory demands that may be especially challenging for autistic mothers. Despite the high prevalence, no research exists exploring the sensory experiences of autistic mothers, highlighting the gap in current knowledge. Semi-structured interviews were conducted with 7 autistic mothers, data were analysed using thematic analysis identifying 5 major themes: antenatal experiences, sensory experiences in motherhood, the impact of sensory processing difficulties, strategies and needs, diagnosis. This research provides greater insight and understanding into the sensory experiences of autistic mothers which can influence earlier diagnosis and inform appropriate support and adaptations for autistic mothers in a variety of different sectors and highlights a possible emerging role for Occupational Therapists.

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16. van de Wouw M, Walsh CJ, Vigano GMD, Lyte JM, Boehme M, Gual-Grau A, Crispie F, Walsh AM, Clarke G, Dinan TG, Cotter PD, Cryan JF. Kefir ameliorates specific microbiota-gut-brain axis impairments in a mouse model relevant to autism spectrum disorder. Brain, behavior, and immunity. 2021; 97: 119-34.

Autism spectrum disorder (ASD) is one of the most severe developmental disorders, affecting on average 1 in 150 children worldwide. There is a great need for more effective strategies to improve quality of life in ASD subjects. The gut microbiome has emerged as a potential therapeutic target in ASD. A novel modulator of the gut microbiome, the traditionally fermented milk drink kefir, has recently been shown to modulate the microbiota and decrease repetitive behaviour, one of the hallmarks of ASD, in mice. As such, we hypothesized that kefir could ameliorate behavioural deficits in a mouse model relevant to ASD; the BTBR T(+) Itpr3(tf)/J mouse strain. To this end, adult mice were administered either kefir (UK4) or a milk control for three weeks as treatment lead-in, after which they were assessed for their behavioural phenotype using a battery of tests. In addition, we assessed systemic immunity by flow cytometry and the gut microbiome using shotgun metagenomic sequencing. We found that indeed kefir decreased repetitive behaviour in this mouse model. Furthermore, kefir prolonged stress-induced increases in corticosterone 60 min post-stress, which was accompanied by an ameliorated innate immune response as measured by LY6C(hi) monocyte levels. In addition, kefir increased the levels of anti-inflammatory Treg cells in mesenteric lymph nodes (MLNs). Kefir also increased the relative abundance of Lachnospiraceae bacterium A2, which correlated with reduced repetitive behaviour and increased Treg cells in MLNs. Functionally, kefir modulated various predicted gut microbial pathways, including the gut-brain module S-Adenosylmethionine (SAM) synthesis, as well as L-valine biosynthesis and pyruvate fermentation to isobutanol, which all correlated with repetitive behaviour. Taken together our data show that kefir modulates peripheral immunoregulation, can ameliorate specific ASD behavioural dysfunctions and modulates selective aspects of the composition and function of the gut microbiome, indicating that kefir supplementation might prove a viable strategy in improving quality of life in ASD subjects.

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17. Ward EK, Buitelaar JK, Hunnius S. Implicit learning in 3-year-olds with high and low likelihood of autism shows no evidence of precision weighting differences. Developmental science. 2022; 25(2): e13158.

Predictive Processing accounts of autism claim that autistic individuals assign higher precision to their prediction errors than non-autistic individuals, that is, autistic individuals update their predictions more readily when faced with unexpected sensory input. Since setting the level of precision is a fundamental part of perception and learning, we propose that such differences should be detectable in various domains at a very early age, before clinical symptoms have fully emerged. We therefore tested 3-year-old younger siblings of autistic children, with a high likelihood of later receiving an autism diagnosis themselves, and low-likelihood children with an older sibling without autism. We used a novel implicit learning paradigm to examine the effect of sensory noise on the predictions participants built. In order to learn a sequence, our participants had to select which visual information to attend to and disregard low-level prediction errors caused by the sensory noise, which the theory claims is more difficult for autistic individuals. Contrary to the proposed higher precision-weighting of prediction errors in autism, the high-likelihood children did not show signs of updating their predictions more readily when we added sensory noise compared to the low-likelihood children, either in their reaction times or in the recurrence and determinism of their response locations. These results raise challenges for Predictive Processing theories of autism, specifically for the notion that prediction errors are inflexibly highly weighted by individuals with autism.

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18. Zhao Z, Zhu Z, Zhang X, Tang H, Xing J, Hu X, Lu J, Qu X. Identifying Autism with Head Movement Features by Implementing Machine Learning Algorithms. Journal of autism and developmental disorders. 2021.

Our study investigated the feasibility of using head movement features to identify individuals with autism spectrum disorder (ASD). Children with ASD and typical development (TD) were required to answer ten yes-no questions, and they were encouraged to nod/shake head while doing so. The head rotation range (RR) and the amount of rotation per minute (ARPM) in the pitch (head nodding direction), yaw (head shaking direction) and roll (lateral head inclination) directions were computed, and further fed into machine learning classifiers as the input features. The maximum classification accuracy of 92.11% was achieved with the decision tree classifier with two features (i.e., RR_Pitch and ARPM_Yaw). Our study suggests that head movement dynamics contain objective biomarkers that could identify ASD.

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