1. Allman MJ, Pelphrey KA, Meck WH. {{Developmental neuroscience of time and number: implications for autism and other neurodevelopmental disabilities}}. {Front Integr Neurosci};2011 (Oct 14);6:7.
Estimations of time and number share many similarities in both non-humans and man. The primary focus of this review is on the development of time and number sense across infancy and childhood, and neuropsychological findings as they relate to time and number discrimination in infants and adults. Discussion of these findings is couched within a mode-control model of timing and counting which assumes time and number share a common magnitude representation system. A basic sense of time and number likely serves as the foundation for advanced numerical and temporal competence, and aspects of higher cognition-this will be discussed as it relates to typical childhood, and certain developmental disorders, including autism spectrum disorder. Directions for future research in the developmental neuroscience of time and number (NEUTIN) will also be highlighted.
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2. Badia M, Orgaz MB, Verdugo MA, Ullan AM. {{Patterns and determinants of leisure participation of youth and adults with developmental disabilities}}. {J Intellect Disabil Res};2012 (Mar 8)
Background People with developmental disabilities are at high risk for a limited participation in leisure activities. The aim of this study was to investigate the participation in, preference for and interest in leisure activities of young and adults with developmental disabilities, and to examine the factors associated with leisure activity. Methods A cross-sectional design was used with a convenience sample of 237 people aged 17 to 65, living in the community. Leisure participation was assessed with the Spanish version of Leisure Assessment Inventory. Percentages were calculated by types of activity, and repeated measures anovas were used to analyse the differences between types of activities, and mixed anovas to analyse the factors that explain differences in leisure activity participation, preference and interest. Results Leisure social activities and recreation activities at home were mostly solitary and passive in nature and were identified as those being most commonly engaged in. Respondents expressed preference for more social and physical activity, and they were interested in trying out a large number of physical activities. Age and type of schooling determine participation in leisure activity. The results underscore the differences in leisure activity participation, preference and interest depending on the severity of the disability. Conclusions The findings reveal interesting patterns of participation in leisure activities from the viewpoint of youngsters and adults with developmental disabilities. Leisure participation among people with developmental disabilities is likely to be more affected by environmental factors than by personal factors.
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3. Churches O, Baron-Cohen S, Ring H. {{The psychophysiology of narrower face processing in autism spectrum conditions}}. {Neuroreport};2012 (Mar 6)
Faces are encountered across a huge range of visual conditions, including differences in light, distance and visibility. To accurately detect all faces under all these conditions, the face detection system must be suitably generalized. However, in autism spectrum conditions (ASCs), the typical generalization of perceptual learning is narrower. Here, we tested the generalization of the face detection system in a sample of adults with ASCs and a matched control group without ASCs. We recorded electroencephalography while participants viewed images of actual faces, face-like objects and non-face-like objects. Analysis of the N170 event-related potential component, which is related to the early stages of face detection, showed that the two participant groups were comparable in the activation of the N170 to actual faces and face-like objects, but that the typical control group showed an increased N170 for non-face-like objects over the group with ASCs. This indicates that the face detection system is less generalized (narrower) in ASCs than in typical development. We propose that the reduced social interest characteristic of ASCs is associated with a narrower face detection system that is less reliable in detecting all the faces in the environment.
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4. Derosa BA, Van Baaren JM, Dubey GK, Vance JM, Pericak-Vance MA, Dykxhoorn DM. {{Derivation of autism spectrum disorder-specific induced pluripotent stem cells from peripheral blood mononuclear cells}}. {Neurosci Lett};2012 (Mar 6)
Induced pluripotent stem cells (iPSCs) hold tremendous potential both as a biological tool to uncover the pathophysiology of disease by creating relevant cell models and as a source of stem cells for cell-based therapeutic applications. Typically, iPSCs have been derived by the transgenic overexpression of transcription factors associated with progenitor cell or stem cell function in fibroblasts derived from skin biopsies. However, the need for skin punch biopsies to derive fibroblasts for reprogramming can present a barrier to study participation among certain populations of individuals, including children with autism spectrum disorders (ASDs). In addition, the acquisition of skin punch biopsies in non-clinic settings presents a challenge. One potential mechanism to avoid these limitations would be the use of peripheral blood mononuclear cells (PBMCs) as the source of the cells for reprogramming. In this article we describe the derivation of iPSC lines from PBMCs isolated from the whole blood of autistic children, and their subsequent differentiation in GABAergic neurons.
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5. Goebel-Goody SM, Wilson-Wallis ED, Royston S, Tagliatela SM, Naegele JR, Lombroso PJ. {{Genetic manipulation of STEP reverses behavioral abnormalities in a fragile X syndrome mouse model}}. {Genes Brain Behav};2012 (Mar 8)
Fragile X syndrome (FXS), the most common inherited form of intellectual disability and prevailing known genetic basis of autism, is caused by an expansion in the Fmr1 gene that prevents transcription and translation of fragile X mental retardation protein (FMRP). FMRP binds to and controls translation of mRNAs downstream of metabotropic glutamate receptor (mGluR) activation. Recent work demonstrates that FMRP interacts with the transcript encoding striatal-enriched protein tyrosine phosphatase (STEP) (Ptpn5). STEP opposes synaptic strengthening and promotes synaptic weakening by dephosphorylating its substrates, including ERK1/2, p38, Fyn, Pyk2, and subunits of NMDA and AMPA receptors. Here we demonstrate that basal levels of STEP are elevated and mGluR-dependent STEP synthesis is absent in Fmr1(KO) mice. We hypothesized that the weakened synaptic strength and behavioral abnormalities reported in FXS may be linked to excess levels of STEP. To test this hypothesis, we reduced or eliminated STEP genetically in Fmr1(KO) mice and assessed mice in a battery of behavioral tests. In addition to attenuating audiogenic seizures and seizure-induced c-Fos activation in the periaqueductal gray, genetically reducing STEP in Fmr1(KO) mice reversed characteristic social abnormalities, including approach, investigation, and anxiety. Loss of STEP also corrected select non-social anxiety-related behaviors in Fmr1(KO) mice, such as light side exploration in the light/dark box. Our findings indicate that genetically reducing STEP significantly diminishes seizures and restores select social and non-social anxiety-related behaviors in Fmr1(KO) mice, suggesting that strategies to inhibit STEP activity may be effective for treating patients with FXS.
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6. Grillo E, Villard L, Clarke A, Ben Zeev B, Pineda M, Bahi-Buisson N, Hryniewiecka-Jaworska A, Bienvenu T, Armstrong J, Martinez AR, Mari F, Veneselli E, Russo S, Vignoli A, Pini G, Djuric M, Bisgaard AM, Mejaski-Bosnjak V, Polgar N, Cogliati F, Ravn K, Pintaudi M, Melegh B, Craiu D, Djukic A, Renieri A. {{Rett Networked Database: An integrated clinical and genetic network of Rett syndrome databases}}. {Hum Mutat};2012 (Mar 13)
Rett syndrome (RTT) is a neurodevelopmental disorder with one principal phenotype and several distinct, atypical variants (Zappella, early seizure onset and congenital variants). Mutations in MECP2 are found in most cases of classic RTT but at least two additional genes, CDKL5 and FOXG1, can underlie some (usually variant) cases. There is only limited correlation between genotype and phenotype. The Rett Networked Database (http://www.rettdatabasenetwork.org/) has been established to share clinical an genetic information. Through an ‘adaptor’ process of data harmonization, a set of 293 clinical items and 16 genetic items was generated; 62 clinical and 7 genetic items constitute the core dataset; 23 clinical items contain longitudinal information. The database contains information on 1838 patients from eleven countries (December 2011), with or without mutations in known genes. These numbers can expand indefinitely. Data are entered by a clinician in each center who supervises accuracy. This network was constructed to make available pooled international data for the study of RTT natural history and genotype-phenotype correlation and to indicate the proportion of patients with specific clinical features and mutations. We expect that the network will serve for the recruitment of patients into clinical trials and for developing quality measures to drive up standards of medical management.
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7. Hepburn S. {{Researching the autism spectrum: contemporary perspectives}}. {Am J Psychiatry};2012 (Mar 1);169(3):337.
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8. Howlin P. {{Understanding savant skills in autism}}. {Dev Med Child Neurol};2012 (Mar 13)
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9. Hyman SL, Johnson JK. {{Autism and Pediatric Practice: Toward a Medical Home}}. {J Autism Dev Disord};2012 (Mar 13)
The pediatrician sees a child for 11 well child visits by their third birthday. The provision of continuous primary care supports development of trust with parents, provides opportunity for screening and surveillance of autism spectrum disorders (ASD), allows monitoring the progress of children requiring therapy, and a framework to support and educate families. Families of children with ASD are less likely to report that they receive care in a Medical Home, a practice providing coordinated, accessible, continuous, culturally competent care. They report less access to specialty and family focused care compared to other children with special health care needs. It is a major challenge to identify and effect the solutions necessary to bring Medical Home care to all children with ASD.
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10. Kohls G, Schulte-Ruther M, Nehrkorn B, Muller K, Fink GR, Kamp-Becker I, Herpertz-Dahlmann B, Schultz RT, Konrad K. {{Reward System Dysfunction in Autism Spectrum Disorders}}. {Soc Cogn Affect Neurosci};2012 (Mar 13)
Although it has been suggested, that social deficits of autism spectrum disorders (ASD) are related to reward circuitry dysfunction, very little is known about the neural reward mechanisms in ASD. In the current functional magnetic resonance imaging study, we investigated brain activations in response to both social and monetary reward in a group of children with ASD, relative to matched controls. Participants with ASD showed the expected hypoactivation in the mesocorticolimbic circuitry in response to both reward types. In particular, diminished activation in the nucleus accumbens was observed when money, but not when social reward, was at stake, whereas the amygdala and anterior cingulate cortex were hypoactivated within the ASD group in response to both rewards. These data indicate that the reward circuitry is compromised in ASD in social as well as in non-social, i.e., monetary conditions, which likely contributes to atypical motivated behaviour. Taken together, with incentives used in this study sample, there is evidence for a general reward dysfunction in ASD. However, more ecologically valid social reward paradigms are needed to fully understand, whether there is any domain specificity to the reward deficit that appears evident in ASD, which would be most consistent with the ASD social phenotype.
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11. Liu Y, Hu Z, Xun G, Peng Y, Lu L, Xu X, Xiong Z, Xia L, Liu D, Li W, Zhao J, Xia K. {{Mutation analysis of the NRXN1 gene in a Chinese autism cohort}}. {J Psychiatr Res};2012 (Mar 9)
Autism is a brain developmental disorder characterized by impaired social interaction and communication, as well as restricted and repetitive behaviors. The neurexin-1(NRXN1) gene mapped on chromosome 2p16.3 encodes neurexin, a cell adhesion molecule and receptor in the vertebrate nervous system. Rare de novo alterations and copy number variations (CNVs) suggested neurexin-1 as a candidate gene for the pathogenesis of autism, but data on the gene mutation of neurexin-1 in Chinese Han population with autism are limited. By direct sequencing, we analyzed the entire coding regions and associated splice junctions of neurexin-1 in 313 Chinese autism patients. For exons in which non-synonymous variants were identified, sequencing was performed in 500 healthy controls. We identified 22 variants in the neurexin-1 coding regions, including 7 missense variants, 3 deletions, and 12 synonymous mutations. Among them, 3 missense and 3 synonymous variants were not reported in the dbSNP database and absent in 500 control subjects; whereas 4 missense variants, 3 deletions and 3 synonymous mutations were not reported in the dbSNP database but were identified in the control subjects. However, there is no significant association of these mutations with autism risk. Interestingly, there was a statistically significant association of neurexin-1 SNP P300P (rs2303298) with risk of autism (26.2% vs. 13.8%; chi(2) = 22.487; p = 3.45E-006; OR = 2.152 (1.559-2.970)). Our data suggest a possible association of neurexin-1 with autism risk in Chinese Han population, warranting further large-scale study on this gene.
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12. Maras KL, Bowler DM. {{Eyewitness Testimony in Autism Spectrum Disorder: A Review}}. {J Autism Dev Disord};2012 (Mar 10)
Autism spectrum disorder (ASD) is estimated to affect around 1% of the population, and is characterised by impairments in social interaction, communication, and behavioural flexibility. A number of risk factors indicate that individuals with ASD may become victims or witnesses of crimes. In addition to their social and communication deficits, people with ASD also have very specific memory problems, which impacts on their abilities to recall eyewitnessed events. We begin this review with an overview of the memory difficulties that are experienced by individuals with ASD, before discussing the studies that have specifically examined eyewitness testimony in this group and the implications for investigative practice. Finally, we outline related areas that would be particularly fruitful for future research to explore.
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13. Mathewson KJ, Jetha MK, Drmic IE, Bryson SE, Goldberg JO, Schmidt LA. {{Regional EEG alpha power, coherence, and behavioral symptomatology in autism spectrum disorder}}. {Clin Neurophysiol};2012 (Mar 8)
OBJECTIVE: Although distinct patterns of resting brain electrical activity (EEG) and functional connectivity are believed to distinguish individuals with autism spectrum disorders (ASD) from their unimpaired peers, researchers have only recently begun to link patterns of brain activity and connectivity to behavior in ASD. METHOD: We examined regional eyes-closed and eyes-open EEG alpha power and coherence at rest in relation to self-reported perceptual and social behavior in 15 adults diagnosed with ASD and a matched comparison group of 16 unimpaired adults. RESULTS: The groups did not differ on eyes-closed EEG alpha power or coherence, but adults with ASD showed less alpha suppression for the eyes-open condition than did controls. In the ASD group, preferential attention to detail (perceptual domain) was associated with lower levels of alpha activity and reduced coherence in posterior regions. No relations between social interaction difficulties (social domain) and alpha measures were found for either group alone. CONCLUSIONS: These relations suggest that the processing of perceptual details may be carried out by relatively less synchronized neuronal units in adults with ASD, and may be relatively automatic. SIGNIFICANCE: Findings are discussed in relation to recent models of narrow minicolumnar brain structure and reduced functional neural connectivity in ASD.
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14. Osada H, Coelho de Amorim A, Velosa A, Wan WP, Lotrakul P, Hara H. {{Depression risks in mothers of children with developmental disabilities: A cross-cultural comparison of Brazil, Colombia, Malaysia and Thailand}}. {Int J Soc Psychiatry};2012 (Mar 8)
BACKGROUND: Compared with US or European countries, there are fewer mental health services for mothers of children with developmental disabilities in Latin American and/or Southeast Asian countries. AIMS: To explore the risk of depression in mothers of children with developmental disabilities in countries with a lack of mental health professionals, we conducted cross-cultural comparisons for four countries: Brazil, Colombia, Malaysia and Thailand. METHODS: Using the CES-D, we compared the participants’ depressive symptoms, by which we also estimated the probability of morbid depression. RESULTS: In every country, participants tended to show depressive symptoms. In the CES-D total scores and the numbers of mothers who were observed to have a high level of depressive symptoms, there were significant differences among countries (F = 4.36, p = .006; chi(2) = 10.3, p = .015). CONCLUSIONS: Considering cultural models, we could apply evidence-based intervention to depressive mothers of children, and conduct intervention and treatment for those mothers and evaluate ways of providing better mental health services to these individuals.
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15. Pobbe RL, Pearson BL, Blanchard DC, Blanchard RJ. {{Oxytocin receptor and Mecp2(308/Y) knockout mice exhibit altered expression of autism-related social behaviors}}. {Physiol Behav};2012 (Mar 3)
The development of tasks measuring behaviors specific to the three major symptom categories for autism makes it possible to differentiate mouse models of autism spectrum disorders (ASD) in terms of changes in these specific categories. Prior studies indicate that BTBR T+tf/J mice, the strain that has been evaluated most extensively, show autism-relevant changes in all three symptom categories; reciprocal social interactions; communication; and repetitive, ritualized behaviors. This report reviews the behaviors of oxytocin receptor (Oxtr) and Mecp2(308/Y) wild-type (WT) and knockout (KO) mice, in a number of tests specifically designed to provide information on behaviors that may show functional parallels to the core symptoms of ASD. Oxtr KO mice show robust decreases in reciprocal social interactions, and reduced levels of communication, but no changes in repetitive, ritualized behaviors; whereas Mecp2(308/Y) KO mice show a slight but consistent enhancement of social behavior and communication, and no changes in repetitive, ritualized behaviors. This data base, although small, strongly indicates that mouse models can sort the diagnostic symptoms of autism, and suggests that biological and physiological analyses of these strains may be capable of providing differential information on the brain systems involved in particular symptoms of this disorder. Profiles of behavioral changes in other mouse models of ASD should provide additional specificity in the search for biomarkers associated with particular ASD symptoms and symptom clusters.
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16. Reed P, Hawthorn R, Bolger S, Meredith K, Bishop R. {{Disrupted Stimulus Control But Not Reward Sensitivity in Individuals with Autism Spectrum Disorders: A Matching Law Analysis}}. {J Autism Dev Disord};2012 (Mar 10)
The matching law suggests that behavior is emitted in proportion to the level of reinforcement available. The current study investigated this effect in individuals with autism spectrum disorders (ASD), and focused on the effects of magnitude of reinforcement (Study 1), and rate of reinforcement (Studies 2 and 3), on matching performance. Studies 1 and 2 employed lower functioning children with ASD, and demonstrated matching in both groups, but that the group with ASD displayed greater levels of stimulus bias. Study 3 employed higher functioning children with ASD, and found little evidence of matching, but higher stimulus bias in the group with ASD. These effects suggest a disruption of stimulus control, but not reward sensitivity, in individuals with ASD.
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17. Richards C, Oliver C, Nelson L, Moss J. {{Self-injurious behaviour in individuals with autism spectrum disorder and intellectual disability}}. {J Intellect Disabil Res};2012 (Mar 8)
Background Autism spectrum disorder (ASD) has been identified as a risk marker for self-injurious behaviour. In this study we aimed to describe the prevalence, topography and correlates of self-injury in individuals with ASD in contrast to individuals with Fragile X and Down syndromes and examine person characteristics associated with self-injury across and within these groups. Method Carers of individuals with ASD (n = 149; mean age = 9.98, SD = 4.86), Fragile X syndrome (n = 123; mean age = 15.32, SD = 8.74) and Down syndrome (n = 49; mean age = 15.84, SD = 12.59) completed questionnaires relating to the presence and topography of self-injury. Information was also gathered regarding demographic characteristics, affect, autistic behaviour, hyperactivity, impulsivity and repetitive behaviour. Results Self-injurious behaviour was displayed by 50% of the ASD sample: a significantly higher prevalence than in the Down syndrome group (18.4%) but broadly similar to the prevalence in Fragile X syndrome (54.5%). Self-injury was associated with significantly higher levels of autistic behaviour within the Down and Fragile X syndrome groups. Within the ASD group, the presence of self-injury was associated with significantly higher levels of impulsivity and hyperactivity, negative affect and significantly lower levels of ability and speech. Conclusions Self-injurious behaviour is prevalent in individuals with ASD and the presence of ASD phenomenology increases the risk of self-injury in individuals with known genetic disorders but without a diagnosis of idiopathic autism. Person characteristics associated with self-injury in ASD indicate a role for impaired behavioural inhibition, low levels of ability and negative affect in the development of self-injurious behaviour.
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18. Storch EA, Arnold EB, Jones AM, Ale CM, Wood JJ, Ehrenreich-May J, Lewin AB, Mutch PJ, Murphy TK. {{The Role of Co-Occurring Disruptive Behavior in the Clinical Presentation of Children and Adolescents with Anxiety in the Context of Autism Spectrum Disorders}}. {Child Psychiatry Hum Dev};2012 (Mar 10)
This study explored the impact of disruptive behavior disorder (DBD) comorbidity on theoretically relevant correlates among 87 children and adolescents with autism spectrum disorders (ASD) and clinically significant anxiety. Relative to youth with ASD and anxiety alone, participants with ASD, anxiety, and DBD: (a) presented with significantly more severe anxiety symptoms per clinician-, parent-, and self-report; (b) were more likely to be prescribed antipsychotic medication but were no more likely to receive additional psychosocial and educational interventions; and (c) experienced significantly greater functional impairment and family interference. These results suggest that co-occurring DBD in the context of ASD and anxiety confers greater risk for heightened symptom severity and functional impairment, and may be linked with increased prescription of antipsychotic medication.
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19. Wang J, Lee LC, Chen YS, Hsu JW. {{Assessing Autistic Traits in a Taiwan Preschool Population: Cross-Cultural Validation of the Social Responsiveness Scale (SRS)}}. {J Autism Dev Disord};2012 (Mar 10)
The cross-cultural validity of the Mandarin-adaptation of the social responsiveness scale (SRS) was examined in a sample of N = 307 participants in Taiwan, 140 typically developing and 167 with clinically-diagnosed developmental disorders. This scale is an autism assessment tool that provides a quantitative rather than categorical measure of social impairment in the general population. SRS total and subscale scores distinguished significantly between autism spectrum disorder and other developmental disorders (p < 0.01). Total SRS scores and sensitivity and specificity of the scale for diagnosing developmental disorders in the Taiwan study were similar to those observed in Western studies. These findings support the cross-cultural validity of the SRS scale for detecting autistic traits and for distinguishing between autism and other neuropsychiatric conditions.
