1. Abbott AE, Nair A, Keown CL, Datko M, Jahedi A, Fishman I, Muller RA. {{Patterns of Atypical Functional Connectivity and Behavioral Links in Autism Differ Between Default, Salience, and Executive Networks}}. {Cereb Cortex};2015 (Sep 7)
Autism spectrum disorder (ASD) is characterized by atypical brain network organization, but findings have been inconsistent. While methodological and maturational factors have been considered, the network specificity of connectivity abnormalities remains incompletely understood. We investigated intrinsic functional connectivity (iFC) for four « core » functional networks-default-mode (DMN), salience (SN), and left (lECN) and right executive control (rECN). Resting-state functional MRI data from 75 children and adolescents (37 ASD, 38 typically developing [TD]) were included. Functional connectivity within and between networks was analyzed for regions of interest (ROIs) and whole brain, compared between groups, and correlated with behavioral scores. ROI analyses showed overconnectivity (ASD > TD), especially between DMN and ECN. Whole-brain results were mixed. While predominant overconnectivity was found for DMN (posterior cingulate seed) and rECN (right inferior parietal seed), predominant underconnectivity was found for SN (right anterior insula seed) and lECN (left inferior parietal seed). In the ASD group, reduced SN integrity was associated with sensory and sociocommunicative symptoms. In conclusion, atypical connectivity in ASD is network-specific, ranging from extensive overconnectivity (DMN, rECN) to extensive underconnectivity (SN, lECN). Links between iFC and behavior differed between groups. Core symptomatology in the ASD group was predominantly related to connectivity within the salience network.
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2. Bennabi M, Delorme R, Oliveira J, Fortier C, Lajnef M, Boukouaci W, Feugeas JP, Marzais F, Gaman A, Charron D, Ghaleh B, Krishnamoorthy R, Leboyer M, Tamouza R. {{Dectin-1 Polymorphism: A Genetic Disease Specifier in Autism Spectrum Disorders?}}. {PLoS One};2015;10(9):e0137339.
INTRODUCTION: In autism spectrum disorders (ASD), complex gene-environment interactions contribute to disease onset and progress. Given that gastro-intestinal dysfunctions are common in ASD, we postulated involvement of microbial dysbiosis in ASD and investigated, under a case-control design, the influence of DNA polymorphisms in the CLEC7A gene that encodes a pivotal fungal sensor, Dectin-1. MATERIAL AND METHODS: DNAs from 478 ASD patients and 351 healthy controls (HC) were analyzed for the CLEC7A rs16910631G/A and rs2078178 A/G single nucleotide polymorphisms (SNPs). Differences in the distribution of allele, genotype and haplotype by Chi-square testing and nonparametric analysis by Kruskal-Wallis/Mann-Whitney tests, where appropriate, were performed. The free statistical package R.2.13 software was used for the statistical analysis. RESULTS: We found that the CLEC7A rs2078178 G allele and GG genotype were more prevalent in HC as compared to ASD but failed to reach statistical significance for the latter (pc = 0.01, 0.06 respectively). However, after phenotype-based stratification, the CLEC7A rs2078178 G allele and GG genotype were found to be significantly more frequent in the Asperger group as compared to other ASD subsets (pc = 0.02, 0.01), a finding reinforced by haplotype analysis (rs2078178/rs16910631 G-G/G-G) (pc = 0.002). Further, intellectual quotient (IQ)-based stratification of ASD patients revealed that IQ values increase linearly along the CLEC7A rs2078178 AA, AG and GG genotypes (p = 0.05) and in a recessive manner (GG vs. AA+AG p = 0.02), further confirmed by haplotype distribution (CLEC7A rs2078178-16910631; A-G/A-G, A-G/G-G and G-G/G-G, p = 0.02, G-G/G-G vs. others, p = 0.01). CONCLUSION: Our data suggest that the genetic diversity of CLEC7A gene influences the ASD phenotype by behaving as a disease specifier and imply that the genetic control of innate immune response could determine the ASD phenotype.
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3. Brown HK, Plourde N, Ouellette-Kuntz H, Vigod S, Cobigo V. {{Brief report: cervical cancer screening in women with intellectual and developmental disabilities who have had a pregnancy}}. {J Intellect Disabil Res};2015 (Sep 10)
BACKGROUND: Women with intellectual and developmental disabilities (IDD) have lower cervical cancer screening rates than women without IDD. Key barriers to screening uptake include physician or caregiver assumptions that screening is unnecessary because women with IDD are not sexually active. Our objective was to compare cervical cancer screening rates in women with and without IDD who had had a pregnancy. METHOD: We conducted a population-based retrospective cohort study using linked Ontario (Canada) health and social services administrative data. We identified 20- to 64-year-old women with (N = 5033) and without (N = 527 437) IDD who had had a pregnancy. We examined the occurrence of cervical cancer screening between April 1, 2007 and March 31, 2010. We compared screening rates in women with and without IDD using logistic regression, controlling for age, region of residence, neighbourhood income quintile and morbidity level. RESULTS: Women with IDD who had had a pregnancy were more likely than those without IDD to be young, to live in the lowest neighbourhood income quintile, to live in rural areas and to have high or very high morbidity. Even after controlling for these factors, women with IDD were less likely than women without IDD to be screened (67.7% vs. 77.0%; adjusted odds ratio 0.61; 95% confidence interval 0.58-0.65). CONCLUSIONS: Even among women who have had a pregnancy and are therefore known to have been sexually active, women with IDD face significant disparities in cervical cancer screening. Strategies to promote equitable uptake of cervical cancer screening for women with IDD need to be implemented.
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4. Dell’Osso L, Dalle Luche R, Maj M. {{Adult autism spectrum as a transnosographic dimension}}. {CNS Spectr};2015 (Sep 9):1-3.
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5. Hayes SJ, Andrew M, Elliott D, Gowen E, Bennett SJ. {{Low Fidelity Imitation of Atypical Biological Kinematics in Autism Spectrum Disorders Is Modulated by Self-Generated Selective Attention}}. {J Autism Dev Disord};2015 (Sep 9)
We examined whether adults with autism had difficulty imitating atypical biological kinematics. To reduce the impact that higher-order processes have on imitation we used a non-human agent model to control social attention, and removed end-state target goals in half of the trials to minimise goal-directed attention. Findings showed that only neurotypical adults imitated atypical biological kinematics. Adults with autism did, however, become significantly more accurate at imitating movement time. This confirmed they engaged in the task, and that sensorimotor adaptation was self-regulated. The attentional bias to movement time suggests the attenuation in imitating kinematics might be a compensatory strategy due to deficits in lower-level visuomotor processes associated with self-other mapping, or selective attention modulated the processes that represent biological kinematics.
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6. Lawson RP, Friston KJ, Rees G. {{A more precise look at context in autism}}. {Proc Natl Acad Sci U S A};2015 (Sep 10)
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7. Moreno-Ramos OA, Olivares AM, Haider NB, de Autismo LC, Lattig MC. {{Whole-Exome Sequencing in a South American Cohort Links ALDH1A3, FOXN1 and Retinoic Acid Regulation Pathways to Autism Spectrum Disorders}}. {PLoS One};2015;10(9):e0135927.
Autism spectrum disorders (ASDs) are a range of complex neurodevelopmental conditions principally characterized by dysfunctions linked to mental development. Previous studies have shown that there are more than 1000 genes likely involved in ASD, expressed mainly in brain and highly interconnected among them. We applied whole exome sequencing in Colombian-South American trios. Two missense novel SNVs were found in the same child: ALDH1A3 (RefSeq NM_000693: c.1514T>C (p.I505T)) and FOXN1 (RefSeq NM_003593: c.146C>T (p.S49L)). Gene expression studies reveal that Aldh1a3 and Foxn1 are expressed in ~E13.5 mouse embryonic brain, as well as in adult piriform cortex (PC; ~P30). Conserved Retinoic Acid Response Elements (RAREs) upstream of human ALDH1A3 and FOXN1 and in mouse Aldh1a3 and Foxn1 genes were revealed using bioinformatic approximation. Chromatin immunoprecipitation (ChIP) assay using Retinoid Acid Receptor B (Rarb) as the immunoprecipitation target suggests RA regulation of Aldh1a3 and Foxn1 in mice. Our results frame a possible link of RA regulation in brain to ASD etiology, and a feasible non-additive effect of two apparently unrelated variants in ALDH1A3 and FOXN1 recognizing that every result given by next generation sequencing should be cautiously analyzed, as it might be an incidental finding.
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8. Nanba E. {{[Fragile X syndrome: a review of diagnosis and treatment]}}. {No To Hattatsu};2015 (Mar);47(2):112-116.
9. Pugliese CE, Anthony LG, Strang JF, Dudley K, Wallace GL, Naiman DQ, Kenworthy L. {{Longitudinal Examination of Adaptive Behavior in Autism Spectrum Disorders: Influence of Executive Function}}. {J Autism Dev Disord};2015 (Sep 9)
This study characterizes longitudinal change in adaptive behavior in 64 children and adolescents with autism spectrum disorder (ASD) without intellectual disability evaluated on multiple occasions, and examines whether prior estimate of executive function (EF) problems predicts future adaptive behavior scores. Compared to standardized estimates for their developmental stage, adaptive behavior in most participants was impaired and did not improve over time. Prior EF predicted later adaptive behavior in daily living skills and socialization domains after controlling for age and IQ. Self-monitoring behaviors robustly predicted later adaptive behavior in all domains (d = 0.60-0.94). Results support targeting treatment of adaptive skills in ASD, as well as the importance of assessing for EF problems that may contribute to adaptive behavior difficulties.
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10. Richter JD, Bassell GJ, Klann E. {{Dysregulation and restoration of translational homeostasis in fragile X syndrome}}. {Nat Rev Neurosci};2015 (Sep 9)
Fragile X syndrome (FXS), the most-frequently inherited form of intellectual disability and the most-prevalent single-gene cause of autism, results from a lack of fragile X mental retardation protein (FMRP), an RNA-binding protein that acts, in most cases, to repress translation. Multiple pharmacological and genetic manipulations that target receptors, scaffolding proteins, kinases and translational control proteins can rescue neuronal morphology, synaptic function and behavioural phenotypes in FXS model mice, presumably by reducing excessive neuronal translation to normal levels. Such rescue strategies might also be explored in the future to identify the mRNAs that are critical for FXS pathophysiology.
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11. Sato JR, Vidal M, de Siqueira Santos S, Massirer KB, Fujita A. {{Complex network measures in Autism Spectrum Disorders}}. {IEEE/ACM Trans Comput Biol Bioinform};2015 (Sep 3)
Recent studies have suggested abnormal brain network organization in subjects with Autism Spectrum Disorders (ASD). Here we applied spectral clustering algorithm, diverse centrality measures (betweenness (BC), clustering (CC), eigenvector (EC), and degree (DC)), and also the network entropy (NE) to identify brain sub-systems associated with ASD. We have found that BC increases in the following ASD clusters: in the somatomotor, default-mode, cerebellar, and fronto-parietal. On the other hand, CC, EC, and DC decrease in the somatomotor, default-mode, and cerebellar clusters. Additionally, NE decreases in ASD in the cerebellar cluster. These findings reinforce the hypothesis of under-connectivity in ASD and suggest that the difference in the network organization is more prominent in the cerebellar system. The cerebellar cluster presents reduced NE in ASD, which relates to a more regular organization of the networks. These results might be important to improve current understanding about the etiological processes and the development of potential tools supporting diagnosis and therapeutic interventions.
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12. Sharer E, Crocetti D, Muschelli J, Barber AD, Nebel MB, Caffo BS, Pekar JJ, Mostofsky SH. {{Neural Correlates of Visuomotor Learning in Autism}}. {J Child Neurol};2015 (Sep 8)
Motor impairments are prevalent in children with autism spectrum disorder. The Serial Reaction Time Task, a well-established visuomotor sequence learning probe, has produced inconsistent behavioral findings in individuals with autism. Moreover, it remains unclear how underlying neural processes for visuomotor learning in children with autism compare to processes for typically developing children. Neural activity differences were assessed using functional magnetic resonance imaging during a modified version of the Serial Reaction Time Task in children with and without autism. Though there was no group difference in visuomotor sequence learning, underlying patterns of neural activation significantly differed when comparing sequence (ie, learning) to random (ie, nonlearning) blocks. Children with autism demonstrated decreased activity in brain regions implicated in visuomotor sequence learning: superior temporal sulcus and posterior cingulate cortex. The findings implicate differences in brain mechanisms that support initial sequence learning in autism and can help explain behavioral observations of autism-associated impairments in skill development (motor, social, communicative) reliant on visuomotor integration.
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13. Stamova B, Ander BP, Barger N, Sharp FR, Schumann CM. {{Specific Regional and Age-Related SmallNoncoding RNA Expression Patterns Within Superior Temporal Gyrus of Typical Human Brains Are Less Distinct in Autism Brains}}. {J Child Neurol};2015 (Sep 8)
Small noncoding RNAs play a critical role in regulating messenger RNA throughout brain development and when altered could have profound effects leading to disorders such as autism spectrum disorders (ASD). We assessed small noncoding RNAs, including microRNA and small nucleolar RNA, in superior temporal sulcus association cortex and primary auditory cortex in typical and ASD brains from early childhood to adulthood. Typical small noncoding RNA expression profiles were less distinct in ASD, both between regions and changes with age. Typical micro-RNA coexpression associations were absent in ASD brains. miR-132, miR-103, and miR-320 micro-RNAs were dysregulated in ASD and have previously been associated with autism spectrum disorders. These diminished region- and age-related micro-RNA expression profiles are in line with previously reported findings of attenuated messenger RNA and long noncoding RNA in ASD brain. This study demonstrates alterations in superior temporal sulcus in ASD, a region implicated in social impairment, and is the first to demonstrate molecular alterations in the primary auditory cortex.
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14. Vanmarcke S, Van Der Hallen R, Evers K, Noens I, Steyaert J, Wagemans J. {{Ultra-Rapid Categorization of Meaningful Real-Life Scenes in Adults With and Without ASD}}. {J Autism Dev Disord};2015 (Sep 9)
In comparison to typically developing (TD) individuals, people with autism spectrum disorder (ASD) appear to be worse in the fast extraction of the global meaning of a situation or picture. Ultra-rapid categorization [paradigm developed by Thorpe et al. (Nature 381:520-522, 1996)] involves such global information processing. We therefore tested a group of adults with and without ASD, without intellectual disability, on a set of ultra-rapid categorization tasks. Individuals with ASD performed equally well as TD individuals except when the task required the categorization of social interactions. These results argue against a general deficit in ultra-rapid gist perception in people with ASD, while suggesting a more specific problem with the fast processing of information about social relations.
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15. Wada M, Ide M. {{Rubber hand presentation modulates visuotactile interference effect especially in persons with high autistic traits}}. {Exp Brain Res};2015 (Sep 10)
Persons with high autistic traits showed diverse reactions as to their multisensory integration, whereas neurotypical persons adequately integrate visual and tactile information. Successive visual stimuli sometimes interfere ordering of successive tactile stimuli. Presentation of a hand-shaped object would affect the interference. Besides, its associations with autistic traits have not been reported. Here, we investigated the effect of a rubber hand presentation on interferences to tactile temporal order judgment by successive visual stimuli. We also investigated whether individual differences associated with autistic traits. A rubber hand was placed palm down in front of the participant in one condition, while in other conditions, it was inverted or was not presented. Participants were required to judge the temporal order of tactile stimuli presented to the index finger and ring finger of their unseen right hand, and needed to ignore the visual stimuli placed on the corresponding fingers of the rubber hand. When incongruent visual stimuli were delivered along with presentation of the rubber hand, the participant’s judgment was notably reversed. In contrast, the degree of reversals significantly decreased when the rubber hand was not presented or presented in an inverted direction. Additionally, we found that participants with high autistic traits tended to show large reversal with the rubber hand presentation, while they showed small reversal when the rubber hand was inverted. Our results suggest that rubber hand corresponding to one’s own hand facilitates visuotactile interference. Furthermore, autistic traits may affect the integration of visuotactile inputs when the rubber hand is presented.
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16. Zheng Z, Young E, Swanson A, Weitlauf A, Warren Z, Sarkar N. {{Robot-mediated Imitation Skill Training for Children with Autism}}. {IEEE Trans Neural Syst Rehabil Eng};2015 (Sep 3)
Autism spectrum disorder (ASD) impacts 1 in 68 children in the US, with tremendous individual and societal costs. Technology-aided intervention, more specifically robotic intervention, has gained momentum in recent years due to the inherent affinity of many children with ASD towards technology. In this paper we present a novel robot-mediated intervention system for imitation skill learning, which is considered a core deficit area for children with ASD. The Robot-mediated Imitation Skill Training Architecture (RISTA) is designed in such a manner that it can operate either completely autonomously or in coordination with a human therapist depending on the intervention need. Experimental results are presented from small user studies validating system functionality, assessing user tolerance, and documenting subject performance. Preliminary results show that this novel robotic system draws more attention from the children with ASD and teaches gestures more effectively as compared to a human therapist. While no broad generalized conclusions can be made about the effectiveness of RISTA based on our small user studies, initial results are encouraging and justify further exploration in the future.
