1. Al-Sharbati MM, Al-Farsi YM, Ouhtit A, Waly MI, Al-Shafaee M, Al-Farsi O, Al-Khaduri M, Al-Said MF, Al-Adawi S. {{Awareness about autism among school teachers in Oman: A cross-sectional study}}. {Autism}. 2013.
Children with special needs such as those with autism spectrum disorder have been recorded as ostracized and stigmatized in many parts of the world. Little is known about whether such negative views are present among mainstream teachers in Oman. A cross-sectional study was conducted to evaluate school teachers’ awareness about autism spectrum disorder in an urban region in Oman. A total of 164 teachers were randomly enrolled from five schools. Misconceptions about autism spectrum disorder were found to be common among mainstream teachers in the country. We posit that such lack of awareness was likely to be rooted with sociocultural patterning as well as conflicting views often « spun » by the scientific community and mass media. Enlightened views toward children with autism spectrum disorder should be presented to Omani teachers to overcome misconceptions and negative attitudes toward children with autism spectrum disorder.
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2. Butrimaviciute R, Grieve A. {{Carers’ experiences of being exposed to challenging behaviour in services for autism spectrum disorders}}. {Autism}. 2013.
Previous studies have demonstrated that being exposed to challenging behaviour in services of care can have a negative impact on staff. Recently, challenging behaviour has been linked to people with autism spectrum disorders; however, little research has been aimed at exploring staff’s experiences of facing such behaviour in services for autism spectrum disorders in particular. A qualitative study using interpretative phenomenological analysis was conducted. This method involves thorough exploration of experiences revealed by individuals. A purposive sample (N = 10) was used. Participants were involved in semi-structured interviews which were later analysed according to the guidelines by Smith and Osborn. Four themes were discovered: intense mental and physical engagement, importance of adaptive coping, ambiguous experience of failure and achievement and destructive emotional reactions. Being exposed to challenging behaviour in services for autism spectrum disorders is a complex multi-component experience. The present results allow some insight into personal worlds of staff and might be useful for improving their working environment as well as ensuring a higher quality of care for service users.
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3. Cederlof M, Ohlsson Gotby A, Larsson H, Serlachius E, Boman M, Langstrom N, Landen M, Lichtenstein P. {{Klinefelter syndrome and risk of psychosis, autism and ADHD}}. {J Psychiatr Res}. 2013.
BACKGROUND: Schizophrenia, bipolar disorder, autism spectrum disorders and ADHD might be overrepresented in Klinefelter syndrome, but previous investigations have yielded inconclusive results. METHODS: We compared a national sample of 860 Klinefelter patients in Sweden with 86 000 matched population controls. To assess the risks of schizophrenia, bipolar disorder, autism spectrum disorder and ADHD in Klinefelter patients, we estimated odds ratios and 95% confidence intervals using conditional logistic regressions. RESULTS: Klinefelter patients had almost four times higher risks of schizophrenia, odds ratio (OR) = 3.6, 95% confidence interval (CI) 2.0-6.7 and bipolar disorder (OR = 3.8, CI 1.8-7.6) and about six times higher risk of autism spectrum disorder (OR = 6.2, CI 4.0-9.4) and ADHD (OR = 5.6, CI 4.0-7.8). CONCLUSIONS: The risk of psychosis, autism and ADHD is increased in Klinefelter patients. These findings indicate an X chromosome-related factor in the etiology of the studied psychiatric disorders, and may also have implications for treatment of patients with Klinefelter syndrome.
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4. Chen X, Sun W, Pan Y, Yang Q, Cao K, Zhang J, Zhang Y, Chen M, Chen F, Huang Y, Dai L, Chen S. {{Lithium ameliorates open-field and elevated plus maze behaviors, and brain phospho-glycogen synthase kinase 3-beta expression in fragile X syndrome model mice}}. {Neurosciences (Riyadh)}. 2013; 18(4): 356-62.
OBJECTIVE: To investigate whether lithium modifies open-field and elevated plus maze behavior, and brain phospho-glycogen synthase kinase 3 (P-GSK3beta) expression in Fmr1 knockout mice. METHODS: One hundred and eighty FVB mice, including knockout and wild type, with an age of 30 days were used. An open-field and elevated plus maze was utilized to test behavior, while western blot was used to measure the P-GSK3beta expression. Six groups were formed: control (saline), lithium chloride 30, 60, 90, 120, and 200 mg/kg. The experiments were carried out in the Institute of Neuroscience, Second Affiliated Hospital of Guangzhou Medical University, Guangzhou, China between January and June 2012. RESULTS: Lithium significantly decreased total distance, crossing, central area time, and center entry in the open-field test (p<0.05), and significantly reduced open-arm tracking, open-arm entry, and open-arm time in the elevated plus maze (p<0.05) in knockout mice. In wild type mice, significant changes were observed in both behavior tests in some treatment groups. Lithium ameliorated P-GSK3beta expression in the hippocampus of all the treatment groups in knockout mice (p<0.05). However, lithium did not modify either GSK3beta expression in tissues of knockout mice, or P-GSK3beta or GSK3beta expression in tissues of wild type mice. CONCLUSION: Lithium ameliorated open-field and elevated plus maze behaviors of Fmr1 knockout mice. This effect may be related to its enhancement of P-GSK3beta expression. Our findings suggest that lithium might have a therapeutic effect in fragile X syndrome.
5. Corbett BA, Swain DM, Coke C, Simon D, Newsom C, Houchins-Juarez N, Jenson A, Wang L, Song Y. {{Improvement in Social Deficits in Autism Spectrum Disorders Using a Theatre-Based, Peer-Mediated Intervention}}. {Autism Res}. 2013.
Social Emotional NeuroScience Endocrinology Theatre is a novel intervention program aimed at improving reciprocal social interaction in youth with autism spectrum disorder (ASD) using behavioral strategies and theatrical techniques in a peer-mediated model. Previous research using a 3-month model showed improvement in face perception, social interaction, and reductions in stress. The current study assessed a 2-week summer camp model. Typically developing peers were trained and paired with ASD youth (8-17 years). Social perception and interaction skills were measured before and after treatment using neuropsychological and parental measures. Behavioral coding by reliable, independent raters was conducted within the treatment context (theatre) and outside the setting (playground). Salivary cortisol levels to assess physiological arousal were measured across contexts (home, theatre, and playground). A pretest-posttest design for within-group comparisons was used, and prespecified pairwise comparisons were achieved using a nonparametric Wilcoxon signed-rank test. Significant differences were observed in face processing, social awareness, and social cognition (P < 0.05). Duration of interaction with familiar peers increased significantly over the course of treatment (P < 0.05), while engagement with novel peers outside the treatment setting remained stable. Cortisol levels rose on the first day of camp compared with home values yet declined by the end of treatment and further reduced during posttreatment play with peers. Results corroborate previous findings that the peer-mediated theatre program contributes to improvement in core social deficits in ASD using a short-term, summer camp treatment model. Future studies will explore treatment length and peer familiarity to optimize and generalize gains. Autism Res 2013,: -. (c) 2013 International Society for Autism Research, Wiley Periodicals, Inc.
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6. Gevarter C, O’Reilly MF, Rojeski L, Sammarco N, Lang R, Lancioni GE, Sigafoos J. {{Comparisons of intervention components within augmentative and alternative communication systems for individuals with developmental disabilities: A review of the literature}}. {Res Dev Disabil}. 2013.
Decisions regarding augmentative and alternative communication (AAC) for individuals with developmental disabilities (e.g. what AAC to use and how to teach a person to use a specific AAC modality) should involve consideration of different intervention component options. In an effort to elucidate such decisions and options, this review synthesized 14 studies, published between 2004 and 2012, comparing different AAC intervention components including different symbol sets, instructional strategies, or speech output within aided AAC systems, and different verbal operants within unaided AAC. Evidence supported the following: (a) different instructional strategies such as building motivation, using errorless learning, or adding video models to picture exchange interventions may improve the acquisition or rate of acquisition of picture exchange mands, (b) limited data supports training mimetic (imitated) or mand signs over tacts and (c) differences in symbol sets and speech output levels appeared to have little effect on AAC-based mand acquisition, but listener-based differences should be considered. These findings have implications for future research and clinical practice.
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7. Golomb BA, Erickson LC, Scott-Van Zeeland AA, Koperski S, Haas RH, Wallace DC, Naviaux RK, Lincoln AJ, Reiner GE, Hamilton G. {{Assessing Bioenergetic Compromise in Autism Spectrum Disorder With 31P Magnetic Resonance Spectroscopy: Preliminary Report}}. {J Child Neurol}. 2013.
We sought to examine, via Phosphorus-31 magnetic resonance spectroscopy (31P-MRS) in a case-control design, whether bioenergetic deficits in autism spectrum disorders extend to the brain and muscle. Six cases with autism spectrum disorder with suspected mitochondrial dysfunction (age 6-18 years) and 6 age/sex-matched controls underwent 31P magnetic resonance spectroscopy. The outcomes of focus were muscle resting phosphocreatine and intracellular pH as well as postexercise phosphocreatine recovery time constant and frontal brain phosphocreatine. Intracellular muscle pH was lower in each autism spectrum disorder case than their matched control (6/6, P = .03; P = .0048, paired t test). Muscle phosphocreatine (5/6), brain phosphocreatine (3/4), and muscle phosphocreatine recovery time constant (3/3) trends were in the predicted direction (not all participants completed each). This study introduces 31P magnetic resonance spectroscopy as a noninvasive tool for assessment of mitochondrial function in autism spectrum disorder enabling bioenergetic assessment in brain and provides preliminary evidence suggesting that bioenergetic defects in cases with autism spectrum disorder are present in muscle and may extend to brain.
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8. Griffith GM, Hastings RP, Petalas MA. {{Brief Report: Fathers’ and Mothers’ Ratings of Behavioral and Emotional Problems in Siblings of Children with Autism Spectrum Disorder}}. {J Autism Dev Disord}. 2013.
Debate is ongoing about whether typically developing siblings of children with autism spectrum disorder (ASD) are at greater risk of behavioral or emotional problems than siblings of children without ASD. Most data on behavior is provided by mothers, and we do not know whether fathers’ reports differ. The strengths and difficulties questionnaire (Goodman in J Child Psychol Psychiatry 38(5):581-586, 1997) was completed by 168 mothers and 130 fathers. Parents were more likely to rate siblings as having ‘abnormal’ behavior when compared to a normative population. We found moderate correlations between mother-father ratings. More research may be needed to understand any clinical benefits of gathering data about sibling adjustment from more than one parent in the family. Implications for clinical practice and future research are discussed.
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9. He CX, Portera-Cailliau C. {{The trouble with spines in fragile X syndrome: density, maturity and plasticity}}. {Neuroscience}. 2013; 251: 120-8.
Dendritic spines are the principal recipients of excitatory synaptic inputs and the basic units of neural computation in the mammalian brain. Alterations in the density, size, shape, and turnover of mature spines, or defects in how spines are generated and establish synapses during brain development, could all result in neuronal dysfunction and lead to cognitive and/or behavioral impairments. That spines are abnormal in fragile X syndrome (FXS) and in the best-studied animal model of this disorder, the Fmr1 knockout mouse, is an undeniable fact. But the trouble with spines in FXS is that the exact nature of their defect is still controversial. Here, we argue that the most consistent abnormality of spines in FXS may be a subtle defect in activity-dependent spine plasticity and maturation. We also propose some future directions for research into spine plasticity in FXS at the cellular and ultrastructural levels that could help solve a two-decade-long riddle about the integrity of synapses in this prototypical neurodevelopmental disorder.
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10. Hobson RP. {{The coherence of autism}}. {Autism}. 2013.
There is a growing body of opinion that we should view autism as fractionable into different, largely independent sets of clinical features. The alternative view is that autism is a coherent syndrome in which principal features of the disorder stand in intimate developmental relationship with each other. Studies of congenitally blind children offer support for the latter position and suggest that a source of coherence in autism is restriction in certain forms of perceptually dependent social experience.
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11. Kover ST, Pierpont EI, Kim JS, Brown WT, Abbeduto L. {{A neurodevelopmental perspective on the acquisition of nonverbal cognitive skills in adolescents with fragile x syndrome}}. {Dev Neuropsychol}. 2013; 38(7): 445-60.
This longitudinal study was designed to investigate trajectories of nonverbal cognitive ability in adolescents with fragile X syndrome with respect to the relative influence of fragile X mental retardation protein (FMRP), autism symptom severity, and environmental factors on visualization and fluid reasoning abilities. Males and females with fragile X syndrome (N = 53; ages 10-16 years) were evaluated with the Leiter-R at up to four annual assessments. On average, IQ declined with age. FMRP levels predicted change in fluid reasoning, but not in visualization. The role of FMRP in the neural development that underlies the fragile X syndrome cognitive phenotype is discussed.
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12. Kuo MH, Orsmond GI, Coster WJ, Cohn ES. {{Media use among adolescents with autism spectrum disorder}}. {Autism}. 2013.
This study explores how adolescents with autism spectrum disorder (ASD) use media, and the factors associated with their media use. A total of 91 adolescents with ASD and their parents completed mail-based surveys. In all, 78% of the adolescents with ASD watched television (approximately 2 h/day), and 98% used computers (approximately 5 h/day) on any given day. They most frequently watched cartoons, played computer or video games that involved shooting, and visited websites that contained information on video games. Adolescents with ASD who watched television with parents reported more positive parent-child relationships. Adolescents with ASD who visited social networking websites or received emails from friends reported more positive friendships. The findings help us understand media-use habits of adolescents with ASD and suggest areas for future research.
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13. Lange N, McDougle C. {{Help for the child with autism}}. {Sci Am}. 2013; 309(4): 72-7.
14. Lehti V, Hinkka-Yli-Salomaki S, Cheslack-Postava K, Gissler M, Brown AS, Sourander A. {{The risk of childhood autism among second-generation migrants in Finland: a case–control study}}. {BMC Pediatr}. 2013; 13(1): 171.
BACKGROUND: Studying second-generation immigrants can help in identifying genetic or environmental risk factors for childhood autism. Most previous studies have focused on maternal region of birth and showed inconsistent results. No previous study has been conducted in Finland. METHODS: The study was a nested case–control study based on a national birth cohort. Children born in 1987–2005 and diagnosed with childhood autism by the year 2007 were identified from the Finnish Hospital Discharge Register. Controls were selected from the Finnish Medical Birth Register. Information on maternal and paternal country of birth and mother tongue was collected from the Finnish Central Population Register. There were 1132 cases and 4515 matched controls. The statistical test used was conditional logistic regression analysis. RESULTS: Compared with children with two Finnish parents, the risk of childhood autism was increased for those whose parents are both immigrants (adjusted odds ratio [aOR] 1.8, 95% confidence interval [CI] 1.2–2.7) and for those with only an immigrant mother (aOR 1.8, 95% CI 1.2–2.7), but not for those with only an immigrant father. The risk was increased for those with a mother born in the former Soviet Union or Yugoslavia and for those with a mother or a father born in Asia. Specific parental countries of birth associated with an increased risk were the former Soviet Union, the former Yugoslavia and Vietnam. CONCLUSIONS: In Finland, children who are born to immigrant mothers with or without an immigrant partner, have an increased risk of childhood autism. The risk varies with immigrant parents’ region of birth. The findings may help in identifying possible risk factors, which can be examined in future studies.
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15. Mankoski R, Stockton G, Manos G, Marler S, McQuade R, Forbes RA, Marcus R. {{Aripiprazole treatment of irritability associated with autistic disorder and the relationship between prior antipsychotic exposure, adverse events, and weight change}}. {J Child Adolesc Psychopharmacol}. 2013; 23(8): 572-6.
Abstract Objective: The purpose of this study was to evaluate the impact of prior antipsychotic exposure (PAE) on safety and tolerability outcomes in pediatric subjects receiving aripiprazole treatment. Methods: This study was a post-hoc analysis of pooled data from two 8-week, double-blind, randomized, placebo-controlled studies evaluating aripiprazole for the treatment of irritability in pediatric subjects with autistic disorder, aged 6-17 years. Subjects were stratified by PAE; adverse events (AEs), and changes in weight, and metabolic measures were evaluated. For subjects receiving aripiprazole, regardless of PAE, baseline weight, age, gender, and symptom severity were evaluated in a regression model predicting body weight change. Results: Of 316 randomized subjects, 259 (82.0%) were antipsychotic naive (AN) and 57 (18.0%) had a PAE. Aripiprazole-treated AN subjects were more likely than PAE subjects to report somnolence (11.9% vs. 2.8%), sedation (22.7% vs. 11.1%), or fatigue (17.0% vs. 13.9%). Rates of extrapyramidal disorder and drooling, but not akathisia or tremor, were marginally higher in AN subjects. Overall, 10.8% of aripiprazole-treated AN subjects had at least one AE leading to discontinuation compared with 8.3% of aripiprazole-treated PAE subjects. AN subjects receiving aripiprazole had a larger change in weight from baseline to endpoint compared with those receiving placebo (1.9 vs. 0.7 kg; treatment difference 1.2 kg, 95% CI: 0.5, 1.9) than PAE subjects receiving aripiprazole compared with subjects receiving placebo (0.4 vs. -0.4 kg; treatment difference 0.9 kg, 95% CI: -0.6, 2.4). Regression analysis identified that younger subjects with higher baseline weight z-score were at highest risk for weight gain. There were no significant changes in metabolic measures compared with placebo in either group. Conclusions: Weight gain was more pronounced in AN subjects and more likely to occur in younger subjects with a higher baseline weight z-score. AN subjects were more likely to experience AEs related to somnolence. However, based on discontinuations rates from AEs, overall tolerability was good for both AN and PAE groups. Clinical trial registration: Study of aripiprazole in the treatment of children and adolescents with autistic disorder. Registry: www.clinicaltrials.gov . Identifiers: NCT00332241 and NCT00337571.
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16. McCurdy EE, Cole CL. {{Use of a Peer Support Intervention for Promoting Academic Engagement of Students with Autism in General Education Settings}}. {J Autism Dev Disord}. 2013.
Students with autism spectrum disorder (ASD) have been shown to benefit from being educated in general education classrooms that provide interactions with typically developing peers. However, behaviors exhibited by students with ASD frequently lead to their return to segregated special education settings. Evidence-based interventions that are both cost-efficient and easy to use in general education settings are needed. The purpose of this study was to evaluate the effects of a simple peer support intervention on the minor disruptive, off-task behaviors of three elementary students with high-functioning ASD in three different general education classrooms. Results indicated the peer support intervention was effective in reducing the off-task behaviors of the students with ASD in these inclusion settings. Practical implications and directions for future research are discussed.
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17. Miller L, McGonigle-Chalmers M. {{Exploring Perceptual Skills in Children with Autism Spectrum Disorders: From Target Detection to Dynamic Perceptual Discrimination}}. {J Autism Dev Disord}. 2013.
Perceptual processing in autism is associated with both ‘strengths’ and ‘weaknesses’ but within a literature that varies widely in terms of the assessments used. We report data from 12 children with autism spectrum disorders (ASD) and 12 age and IQ matched neurotypical controls tested on a set of tasks using the same stimuli throughout but systematically changing in difficulty. These tasks ranged through simple detection of stimulus onset to pairwise size discrimination across two approaching targets. Children with ASD were slower than controls even in simple detection tasks, but this did not explain further group differences found in the size discrimination of approaching targets. The results are discussed in terms of impairments in speed of responding in ASD under certain conditions of visuomotor coupling, stimulus presentation and increased information processing demands.
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18. Mills BD, Lai J, Brown TT, Erhart M, Halgren E, Reilly J, Appelbaum M, Moses P. {{Gray matter structure and morphosyntax within a spoken narrative in typically developing children and children with high functioning autism}}. {Dev Neuropsychol}. 2013; 38(7): 461-80.
This study examined the relationship between magnetic resonance imaging (MRI)-based measures of gray matter structure and morphosyntax production in a spoken narrative in 17 typical children (TD) and 11 children with high functioning autism (HFA) between 6 and 13 years of age. In the TD group, cortical structure was related to narrative performance in the left inferior frontal gyrus (Broca’s area), the right middle frontal sulcus, and the right inferior temporal sulcus. No associations were found in children with HFA. These findings suggest a systematic coupling between brain structure and spontaneous language in TD children and a disruption of these relationships in children with HFA.
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19. Pahnke J, Lundgren T, Hursti T, Hirvikoski T. {{Outcomes of an acceptance and commitment therapy-based skills training group for students with high-functioning autism spectrum disorder: A quasi-experimental pilot study}}. {Autism}. 2013.
Autism spectrum disorder is characterized by social impairments and behavioural inflexibility. In this pilot study, the feasibility and outcomes of a 6-week acceptance and commitment therapy-based skills training group were evaluated in a special school setting using a quasi-experimental design (acceptance and commitment therapy/school classes as usual). A total of 28 high-functioning students with autism spectrum disorder (aged 13-21 years) were assessed using self- and teacher-ratings at pre- and post-assessment and 2-month follow-up. All participants completed the skills training, and treatment satisfaction was high. Levels of stress, hyperactivity and emotional distress were reduced in the treatment group. The acceptance and commitment therapy group also reported increased prosocial behaviour. These changes were stable or further improved at the 2-month follow-up. Larger studies are needed to further evaluate the benefits of acceptance and commitment therapy for autism spectrum disorder.
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20. Plummer JT, Evgrafov OV, Bergman MY, Friez M, Haiman CA, Levitt P, Aldinger KA. {{Transcriptional regulation of the MET receptor tyrosine kinase gene by MeCP2 and sex-specific expression in autism and Rett syndrome}}. {Transl Psychiatry}. 2013; 3: e316.
Single nucleotide variants (SNV) in the gene encoding the MET receptor tyrosine kinase have been associated with an increased risk for autism spectrum disorders (ASD). The MET promoter SNV rs1858830 C ‘low activity’ allele is enriched in ASD, associated with reduced protein expression, and impacts functional and structural circuit connectivity in humans. To gain insight into the transcriptional regulation of MET on ASD-risk etiology, we examined an interaction between the methyl CpG-binding protein 2 (MeCP2) and the MET 5′ promoter region. Mutations in MeCP2 cause Rett syndrome (RTT), a predominantly female neurodevelopmental disorder sharing some ASD clinical symptoms. MeCP2 binds to a region of the MET promoter containing the ASD-risk SNV, and displays rs1858830 genotype-specific binding in human neural progenitor cells derived from the olfactory neuroepithelium. MeCP2 binding enhances MET expression in the presence of the rs1858830 C allele, but MET transcription is attenuated by RTT-specific mutations in MeCP2. In the postmortem temporal cortex, a region normally enriched in MET, gene expression is reduced dramatically in females with RTT, although not due to enrichment of the rs1858830 C ‘low activity’ allele. We newly identified a sex-based reduction in MET expression, with male ASD cases, but not female ASD cases compared with sex-matched controls. The experimental data reveal a prominent allele-specific regulation of MET transcription by MeCP2. The mechanisms underlying the pronounced reduction of MET in ASD and RTT temporal cortex are distinct and likely related to factors unique to each disorder, including a noted sex bias.
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21. Robinson EB, Howrigan D, Yang J, Ripke S, Anttila V, Duncan LE, Jostins L, Barrett JC, Medland SE, Macarthur DG, Breen G, O’Donovan MC, Wray NR, Devlin B, Daly MJ, Visscher PM, Sullivan PF, Neale BM. {{Response to ‘Predicting the diagnosis of autism spectrum disorder using gene pathway analysis’}}. {Mol Psychiatry}. 2013.
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22. Steadman PE, Ellegood J, Szulc KU, Turnbull DH, Joyner AL, Henkelman RM, Lerch JP. {{Genetic Effects on Cerebellar Structure Across Mouse Models of Autism Using a Magnetic Resonance Imaging Atlas}}. {Autism Res}. 2013.
Magnetic resonance imaging (MRI) of autism populations is confounded by the inherent heterogeneity in the individuals’ genetics and environment, two factors difficult to control for. Imaging genetic animal models that recapitulate a mutation associated with autism quantify the impact of genetics on brain morphology and mitigate the confounding factors in human studies. Here, we used MRI to image three genetic mouse models with single mutations implicated in autism: Neuroligin-3 R451C knock-in, Methyl-CpG binding protein-2 (MECP2) 308-truncation and integrin beta3 homozygous knockout. This study identified the morphological differences specific to the cerebellum, a structure repeatedly linked to autism in human neuroimaging and postmortem studies. To accomplish a comparative analysis, a segmented cerebellum template was created and used to segment each study image. This template delineated 39 different cerebellar structures. For Neuroligin-3 R451C male mutants, the gray (effect size (ES) = 1.94, FDR q = 0.03) and white (ES = 1.84, q = 0.037) matter of crus II lobule and the gray matter of the paraflocculus (ES = 1.45, q = 0.045) were larger in volume. The MECP2 mutant mice had cerebellar volume changes that increased in scope depending on the genotype: hemizygous males to homozygous females. The integrin beta3 mutant mouse had a drastically smaller cerebellum than controls with 28 out of 39 cerebellar structures smaller. These imaging results are discussed in relation to repetitive behaviors, sociability, and learning in the context of autism. This work further illuminates the cerebellum’s role in autism. Autism Res 2013, : -. (c) 2013 International Society for Autism Research, Wiley Periodicals, Inc.
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23. Udagawa T, Farny NG, Jakovcevski M, Kaphzan H, Alarcon JM, Anilkumar S, Ivshina M, Hurt JA, Nagaoka K, Nalavadi VC, Lorenz LJ, Bassell GJ, Akbarian S, Chattarji S, Klann E, Richter JD. {{Genetic and acute CPEB1 depletion ameliorate fragile X pathophysiology}}. {Nat Med}. 2013.
Fragile X syndrome (FXS), the most common cause of inherited mental retardation and autism, is caused by transcriptional silencing of FMR1, which encodes the translational repressor fragile X mental retardation protein (FMRP). FMRP and cytoplasmic polyadenylation element-binding protein (CPEB), an activator of translation, are present in neuronal dendrites, are predicted to bind many of the same mRNAs and may mediate a translational homeostasis that, when imbalanced, results in FXS. Consistent with this possibility, Fmr1-/y; Cpeb1-/- double-knockout mice displayed amelioration of biochemical, morphological, electrophysiological and behavioral phenotypes associated with FXS. Acute depletion of CPEB1 in the hippocampus of adult Fmr1-/y mice rescued working memory deficits, demonstrating reversal of this FXS phenotype. Finally, we find that FMRP and CPEB1 balance translation at the level of polypeptide elongation. Our results suggest that disruption of translational homeostasis is causal for FXS and that the maintenance of this homeostasis by FMRP and CPEB1 is necessary for normal neurologic function.
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24. Wojcik DZ, Waterman AH, Lestie C, Moulin CJ, Souchay C. {{Metacognitive judgments-of-learning in adolescents with autism spectrum disorder}}. {Autism}. 2013.
This study investigated metacognitive monitoring abilities in adolescents with autism spectrum disorder in two experiments using the judgment-of-learning paradigm. Participants were asked to predict their future recall of unrelated word pairs during the learning phase. Experiment 1 compared judgments-of-learning made immediately after learning and judgments-of-learning made after a delay. We found that both groups overestimated their memory performance but that overall there were no group differences in judgment-of-learning accuracy. Additionally, both groups displayed the standard delayed judgment-of-learning effect (yielding greater judgment accuracy in delayed compared to immediate judgments), suggesting that both groups were able to use appropriate information in making their judgments-of-learning. Experiment 2 assessed whether adolescents with autism spectrum disorder could regulate their study time according to their judgments-of-learning using a self-paced learning procedure. Results showed that both groups spent more time learning items given lower judgments-of-learning. Finally, Experiment 2 showed that judgments-of-learning and study time varied according to item difficulty in both groups. As a whole, these findings demonstrate that adolescents with autism spectrum disorder can accurately gauge their memory performance while learning new word associations and use these skills to control their study time at learning.
