1. Bebko JM, Rhee T, McMorris CA, Ncube BL. {{Spontaneous strategy use in children with autism spectrum disorder: the roles of metamemory and language skills}}. {Front Psychol};2015;6:182.
Metamemory, or beliefs about one’s own memory capabilities, knowing what you know, and knowing what you don’t know, has frequently been linked to the spontaneous use of rehearsal strategies in typically developing children. However, limited research has investigated mnemonic strategy use, metamemory, or the relationship between these two cognitive processes in children with autism spectrum disorders (ASDs). The current study examined the relative strength of metamemory knowledge and language skills as predictors of rehearsal use and memory performance in individuals with ASD. Twenty-one children with ASD and 21 children in a combined comparison group were matched on chronological and verbal mental age. Over two sessions, participants completed a serial recall task, a language measure, and a metamemory questionnaire. Children were classified as rehearsers/non-rehearsers based on behavioral observations and/or verbal reports of strategy use. As expected from previous research, the comparison group had a significantly higher proportion of rehearsers than the ASD group. However, spontaneous rehearsers performed significantly better on the serial recall task than non-rehearsers, regardless of group membership. Children in the comparison group had a higher mean total score on the metamemory questionnaire than the ASD group. However, when examined by rehearsal use, participants classified as rehearsers, regardless of diagnostic group, scored significantly higher on the metamemory questionnaire than non-rehearsers. Finally, across groups, hierarchical regression analyses identified both metamemory and language proficiency as significant predictors of rehearsal strategy use. The fact that the predictors showed the same relationship across the comparison group and the ASD group implies that metamemory and language proficiency, while separate entities, are both fundamental underlying skills contributing to the emergence of rehearsal strategies, and that the results are likely generalizable to other populations with developmental challenges.
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2. Braat S, D’Hulst C, Heulens I, De Rubeis S, Mientjes E, Nelson DL, Willemsen R, Bagni C, Van Dam D, De Deyn PP, Kooy RF. {{The GABA Receptor is an FMRP Target with Therapeutic Potential in Fragile X Syndrome}}. {Cell Cycle};2015 (Mar 19):0.
Previous research indicates that the GABAAergic system is involved in the pathophysiology of the fragile X syndrome, a frequent form of inherited intellectual disability and associated with autism spectrum disorder. However, the molecular mechanism underlying GABAAergic deficits has remained largely unknown. Here, we demonstrate reduced mRNA expression of GABAA receptor subunits in the cortex and cerebellum of young Fmr1 knockout mice. In addition, we show that the previously reported underexpression of specific subunits of the GABAA receptor can be corrected in YAC transgenic rescue mice, containing the full-length human FMR1 gene in an Fmr1 knockout background. Moreover, we demonstrate that FMRP directly binds several GABAA receptor mRNAs. Finally, positive allosteric modulation of GABAA receptors with the neurosteroid ganaxolone can modulate specific behaviours in Fmr1 knockout mice, emphasizing the therapeutic potential of the receptor.
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3. Butler MG, Rafi SK, Manzardo AM. {{High-resolution chromosome ideogram representation of currently recognized genes for autism spectrum disorders}}. {Int J Mol Sci};2015;16(3):6464-6495.
Recently, autism-related research has focused on the identification of various genes and disturbed pathways causing the genetically heterogeneous group of autism spectrum disorders (ASD). The list of autism-related genes has significantly increased due to better awareness with advances in genetic technology and expanding searchable genomic databases. We compiled a master list of known and clinically relevant autism spectrum disorder genes identified with supporting evidence from peer-reviewed medical literature sources by searching key words related to autism and genetics and from authoritative autism-related public access websites, such as the Simons Foundation Autism Research Institute autism genomic database dedicated to gene discovery and characterization. Our list consists of 792 genes arranged in alphabetical order in tabular form with gene symbols placed on high-resolution human chromosome ideograms, thereby enabling clinical and laboratory geneticists and genetic counsellors to access convenient visual images of the location and distribution of ASD genes. Meaningful correlations of the observed phenotype in patients with suspected/confirmed ASD gene(s) at the chromosome region or breakpoint band site can be made to inform diagnosis and gene-based personalized care and provide genetic counselling for families.
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4. Cheng W, Rolls ET, Gu H, Zhang J, Feng J. {{Autism: reduced connectivity between cortical areas involved in face expression, theory of mind, and the sense of self}}. {Brain};2015 (Mar 20)
Whole-brain voxel-based unbiased resting state functional connectivity was analysed in 418 subjects with autism and 509 matched typically developing individuals. We identified a key system in the middle temporal gyrus/superior temporal sulcus region that has reduced cortical functional connectivity (and increased with the medial thalamus), which is implicated in face expression processing involved in social behaviour. This system has reduced functional connectivity with the ventromedial prefrontal cortex, which is implicated in emotion and social communication. The middle temporal gyrus system is also implicated in theory of mind processing. We also identified in autism a second key system in the precuneus/superior parietal lobule region with reduced functional connectivity, which is implicated in spatial functions including of oneself, and of the spatial environment. It is proposed that these two types of functionality, face expression-related, and of one’s self and the environment, are important components of the computations involved in theory of mind, whether of oneself or of others, and that reduced connectivity within and between these regions may make a major contribution to the symptoms of autism.
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5. Dachez J, Ndobo A, Ameline A. {{French Validation of the Multidimensional Attitude Scale Toward Persons with Disabilities (MAS): The Case of Attitudes Toward Autism and Their Moderating Factors}}. {J Autism Dev Disord};2015 (Mar 19)
This research investigates the renewed interest in autism, the stigmatization of persons with autism and the need to better measure such stigmatization. Two studies were thus conducted on 101 and 104 participants in order to validate the French version of the Multidimensional Attitude Scale toward persons with disabilities, and examine the moderating effects of age, gender and contact on such attitudes. Both the exploratory and confirmatory factor analyses yielded a four-dimensional scale, indicating that the observed data fit with the theoretical model and that the sub-scale show an acceptable internal consistency. Results on moderating effect were less clear cut. The discussion deals with the measurement of attitudes toward people with autism as well as the role of social contact.
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6. Fountain C, Zhang Y, Kissin DM, Schieve LA, Jamieson DJ, Rice C, Bearman P. {{Association Between Assisted Reproductive Technology Conception and Autism in California, 1997-2007}}. {Am J Public Health};2015 (Mar 19):e1-e9.
OBJECTIVES: We assessed the association between assisted reproductive technology (ART) and diagnosed autistic disorder in a population-based sample of California births. METHODS: We performed an observational cohort study using linked records from the California Birth Master Files for 1997 through 2007, the California Department of Developmental Services autism caseload for 1997 through 2011, and the Centers for Disease Control and Prevention’s National ART Surveillance System for live births in 1997 through 2007. Participants were all 5 926 251 live births, including 48 865 ART-originated infants and 32 922 cases of autism diagnosed by the Department of Developmental Services. We compared births originated using ART with births originated without ART for incidence of autism. RESULTS: In the full population, the incidence of diagnosed autism was twice as high for ART as non-ART births. The association was diminished by excluding mothers unlikely to use ART; adjustment for demographic and adverse prenatal and perinatal outcomes reduced the association substantially, although statistical significance persisted for mothers aged 20 to 34 years. CONCLUSIONS: The association between ART and autism is primarily explained by adverse prenatal and perinatal outcomes and multiple births. (Am J Public Health. Published online ahead of print March 19, 2015: e1-e9. doi:10.2105/AJPH.2014.302383).
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7. Grinker RR. {{Reframing the Science and Anthropology of Autism}}. {Cult Med Psychiatry};2015 (Mar 20)
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8. Nissenkorn A, Levy-Drummer RS, Bondi O, Renieri A, Villard L, Mari F, Mencarelli MA, Lo Rizzo C, Meloni I, Pineda M, Armstrong J, Clarke A, Bahi-Buisson N, Mejaski BV, Djuric M, Craiu D, Djukic A, Pini G, Bisgaard AM, Melegh B, Vignoli A, Russo S, Anghelescu C, Veneselli E, Hayek J, Ben-Zeev B. {{Epilepsy in Rett syndrome-Lessons from the Rett networked database}}. {Epilepsia};2015 (Mar 19)
OBJECTIVE: Rett syndrome is an X-linked dominant neurodevelopmental disorder caused by mutations in the MECP2 gene, and characterized by cognitive and communicative regression, loss of hand use, and midline hand stereotypies. Epilepsy is a core symptom, but literature is controversial regarding genotype-phenotype correlation. Analysis of data from a large cohort should overcome this shortcoming. METHODS: Data from the Rett Syndrome Networked Database on 1,248 female patients were included. Data on phenotypic and genotypic parameters, age of onset, severity of epilepsy, and type of seizures were collected. Statistical analysis was done using the IBM SPSS Version 21 software, logistic regression, and Kaplan-Meier survival curves. RESULTS: Epilepsy was present in 68.1% of the patients, with uncontrolled seizures in 32.6% of the patients with epilepsy. Mean age of onset of epilepsy was 4.68 +/- (standard deviation) 3.5 years. Younger age of onset was correlated to severity of epilepsy (Spearman correlation r = 0.668, p < 0.01). Patients with late truncating deletions had lower prevalence of epilepsy. Compared to them, the p.R133C mutation, associated with a milder Rett phenotype, increased the risk for epilepsy (odds ratio [OR] 2.46, confidence interval [CI] 95% 1.3-4.66), but not for severe epilepsy. The p.R255X mutation conferred an increased risk for epilepsy (OR 2.07, CI 95% 1.2-3.59) as well as for severe epilepsy (OR 3.4, CI 95% 1.6-7.3). The p.T158M and p.C306C mutations relatively increased the risk for severe epilepsy (OR 3.09 and 2.69, CI 95% 1.48-6.4 and 1.19-6.05, respectively), but not for epilepsy occurrence. SIGNIFICANCE: Various mutations in the MECP2 gene have a different influence on epilepsy, unrelated to the severity of the general Rett phenotype. This might suggest a site-specific effect of MeCp2 on epileptic pathways. Further investigation of these mechanisms should promote better understanding of epileptogenesis in Rett syndrome.
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9. Ouwenga RL, Dougherty J. {{Fmrp targets or not: long, highly brain-expressed genes tend to be implicated in autism and brain disorders}}. {Mol Autism};2015;6:16.
BACKGROUND: Many studies have demonstrated a robust statistical overlap between genes whose transcripts are reported as Fragile X Mental Retardation Protein (Fmrp)-binding targets and genes implicated in various psychiatric disorders, including autism. However, it is not clear how to interpret this overlap as the Fmrp protein itself is not considered to be central to all instances of these conditions. FINDINGS: We tested whether Fmrp binding may be a proxy for some other features of these transcripts. Reviewing recent literature on the cross-linking and immunoprecipitation (CLIP)-derived targets of Fmrp in the brain, and the literature on identifying genes thought to mediate autism and other psychiatric disorders, reveals that both appear to be disproportionately made up of highly brain-expressed genes. This suggests a parsimonious explanation-that the overlap between Fmrp targets and neuropsychiatric candidate genes might be secondary to simple features such as transcript length and robust expression in the brain. Indeed, reanalyzing Fmrp high-throughput sequencing of RNAs isolated by CLIP (HITS-CLIP) data suggests that approximately 60% of CLIP tag depth can be predicted by gene expression, coding sequence length, and transcript length. Furthermore, there is a statistically significant overlap between autism candidate genes and random samples of long, highly brain-expressed genes, whether they are Fmrp targets or not. CONCLUSIONS: Comparison of known Fmrp-binding targets to candidate gene lists should be informed by both of these features.
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10. Schall CM, Wehman P, Brooke V, Graham C, McDonough J, Brooke A, Ham W, Rounds R, Lau S, Allen J. {{Employment Interventions for Individuals with ASD: The Relative Efficacy of Supported Employment With or Without Prior Project SEARCH Training}}. {J Autism Dev Disord};2015 (Mar 20)
This paper presents findings from a retrospective observational records review study that compares the outcomes associated with implementation of supported employment (SE) with and without prior Project SEARCH with ASD Supports (PS-ASD) on wages earned, time spent in intervention, and job retention. Results suggest that SE resulted in competitive employment for 45 adults with ASD. Twenty-five individuals received prior intervention through PS-ASD while the other 20 individuals received SE only. Individuals in this sample who received PS-ASD required fewer hours of intervention. Additionally, individuals in the PS-ASD group achieved a mean higher wage and had higher retention rates than their peers who received SE only. Further research with a larger sample is needed to confirm these findings.
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11. Shefcyk A. {{Count us in: addressing gender disparities in autism research}}. {Autism};2015 (Feb);19(2):131-132.
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12. Wachob D, Lorenzi DG. {{Brief Report: Influence of Physical Activity on Sleep Quality in Children with Autism}}. {J Autism Dev Disord};2015 (Mar 20)
Sleep-related problems are often documented in children with Autism Spectrum Disorders (ASD). This study examined physical activity as a variable that might influence sleep quality in children with ASD. Ten children, ages 9-16 years, were asked to wear accelerometer devices for 7 days in order to track objective measures of activity and sleep quality. Parents of the children also completed the Child’s Sleep Habits Questionnaire and maintained a daily sleep log while their child wore the device. This study demonstrated that though over half of the children were identified as having at least one sleep-related problem, their activity levels were significantly related to their sleep patterns. Specifically, the more physically active children had overall higher sleep quality.
