Pubmed du 12/08/13

Pubmed du jour

2013-08-12 12:03:50

1. Billeci L, Sicca F, Maharatna K, Apicella F, Narzisi A, Campatelli G, Calderoni S, Pioggia G, Muratori F. {{On the application of quantitative EEG for characterizing autistic brain: a systematic review}}. {Front Hum Neurosci};2013;7:442.

Autism-Spectrum Disorders (ASD) are thought to be associated with abnormalities in neural connectivity at both the global and local levels. Quantitative electroencephalography (QEEG) is a non-invasive technique that allows a highly precise measurement of brain function and connectivity. This review encompasses the key findings of QEEG application in subjects with ASD, in order to assess the relevance of this approach in characterizing brain function and clustering phenotypes. QEEG studies evaluating both the spontaneous brain activity and brain signals under controlled experimental stimuli were examined. Despite conflicting results, literature analysis suggests that QEEG features are sensitive to modification in neuronal regulation dysfunction which characterize autistic brain. QEEG may therefore help in detecting regions of altered brain function and connectivity abnormalities, in linking behavior with brain activity, and subgrouping affected individuals within the wide heterogeneity of ASD. The use of advanced techniques for the increase of the specificity and of spatial localization could allow finding distinctive patterns of QEEG abnormalities in ASD subjects, paving the way for the development of tailored intervention strategies.

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2. Deconinck N, Soncarrieu M, Dan B. {{Toward Better Recognition of Early Predictors for Autism Spectrum Disorders}}. {Pediatr Neurol};2013 (Aug 6)

BACKGROUND: Identification and diagnosis of autism spectrum disorders is essentially based on behavioral presentation and developmental history. The current average age at diagnosis is older than 3 years. METHODS: Over the past 15 years, there has been increasing documentation of the early signs of autism spectrum disorders through both individual retrospective parental reports and screening studies. Recent longitudinal studies have focused on early medical and behavioral features of children regarded at risk, namely younger siblings of children with autism spectrum disorders or children who required neonatal intensive care, with a later diagnosis of autism spectrum disorders. RESULTS: Potentially useful early neurological signs and developmental predictors for autism spectrum disorders could be identified, with a typical profile that evolved with age. CONCLUSIONS: Assessment of early social attention and communication skills with adapted scales in children before the age of 18 months in very large community-based settings may lead to high positive predictive values.

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3. Jansch C, Hare DJ. {{An Investigation of the « Jumping to Conclusions » Data-Gathering Bias and Paranoid Thoughts in Asperger Syndrome}}. {J Autism Dev Disord};2013 (Aug 11)

The existence of a data-gathering bias, in the form of jumping to conclusions, and links to paranoid ideation was investigated in Asperger syndrome (AS). People with AS (N = 30) were compared to a neurotypical control group (N = 30) on the Reading the Mind in the Eyes and the Beads tasks, with self-report measures of depression, general anxiety, social anxiety, self-consciousness and paranoid ideation. The AS group performed less well than the control group on the Reading the Mind in the Eyes Task with regard to accuracy but responded more quickly and tended to make decisions on the basis of less evidence on the Beads Task with 50 % demonstrating a clear ‘jumping to conclusions bias’, whereas none of the control group showed such a bias. Depression and general anxiety were associated with paranoid ideation but not data-gathering style, which was contrary to expectation.

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4. Khor AS, Melvin GA, Reid SC, Gray KM. {{Coping, Daily Hassles and Behavior and Emotional Problems in Adolescents with High-Functioning Autism/Asperger’s Disorder}}. {J Autism Dev Disord};2013 (Aug 11)

Although daily hassles and coping are associated with behavior and emotional problems in non-clinical populations, few studies have investigated these relationships in individuals with high-functioning autism/Asperger’s Disorder (HFASD). This study examined the relationships between daily hassles, coping and behavior and emotional problems in adolescents with HFASD. Thirty-one adolescents with HFASD completed questionnaires assessing their coping and behavior and emotional problems, and completed an Ecological Momentary Assessment run via a mobile phone application on their coping and daily hassles. Parents completed questionnaires of the adolescents’ daily hassles, coping, and behavior and emotional problems. The disengagement coping style was associated with significantly higher levels of behavior and emotional problems regardless of respondent or methodology, suggesting it may be a valuable target for intervention.

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5. Lai MC, Lombardo MV, Suckling J, Ruigrok AN, Chakrabarti B, Ecker C, Deoni SC, Craig MC, Murphy DG, Bullmore ET, Baron-Cohen S. {{Biological sex affects the neurobiology of autism}}. {Brain};2013 (Aug 8)

In autism, heterogeneity is the rule rather than the exception. One obvious source of heterogeneity is biological sex. Since autism was first recognized, males with autism have disproportionately skewed research. Females with autism have thus been relatively overlooked, and have generally been assumed to have the same underlying neurobiology as males with autism. Growing evidence, however, suggests that this is an oversimplification that risks obscuring the biological base of autism. This study seeks to answer two questions about how autism is modulated by biological sex at the level of the brain: (i) is the neuroanatomy of autism different in males and females? and (ii) does the neuroanatomy of autism fit predictions from the ‘extreme male brain’ theory of autism, in males and/or in females? Neuroanatomical features derived from voxel-based morphometry were compared in a sample of equal-sized high-functioning male and female adults with and without autism (n = 120, n = 30/group). The first question was investigated using a 2 x 2 factorial design, and by spatial overlap analyses of the neuroanatomy of autism in males and females. The second question was tested through spatial overlap analyses of specific patterns predicted by the extreme male brain theory. We found that the neuroanatomy of autism differed between adult males and females, evidenced by minimal spatial overlap (not different from that occurred under random condition) in both grey and white matter, and substantially large white matter regions showing significant sex x diagnosis interactions in the 2 x 2 factorial design. These suggest that autism manifests differently by biological sex. Furthermore, atypical brain areas in females with autism substantially and non-randomly (P < 0.001) overlapped with areas that were sexually dimorphic in neurotypical controls, in both grey and white matter, suggesting neural ‘masculinization’. This was not seen in males with autism. How differences in neuroanatomy relate to the similarities in cognition between males and females with autism remains to be understood. Future research should stratify by biological sex to reduce heterogeneity and to provide greater insight into the neurobiology of autism.

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6. Liu T, Breslin CM. {{The effect of a picture activity schedule on performance of the MABC-2 for children with autism spectrum disorder}}. {Res Q Exerc Sport};2013 (Jun);84(2):206-212.

PURPOSE: The purpose of this study was to examine the impact of an assessment protocol utilizing a picture activity schedule on the performance of the Movement Assessment Battery for Children-Second Edition (MABC-2) by children with autism spectrum disorder (ASD). METHOD: Twenty-five children (ages 3-16 years; 20 boys, 5 girls) performed the MABC-2 under two different protocols (i.e., traditional protocol and picture activity schedule protocol). In the traditional protocol condition, each child received detailed verbal descriptions and demonstrations prior to the motor skill performance. During the picture activity schedule protocol, a picture of each task was presented to the children and the verbal instructions were minimized to emphasize visual supports. MABC-2 percentile scores were analyzed using a within-subjects repeated-measures analysis of variance. RESULTS: All children were delayed or at risk for delay in both fine and gross motor skill performance during the administration of the traditional protocol. However, when the picture activity schedule protocol was utilized, children showed a significantly higher MABC-2 percentile score (12.4) compared with that of the traditional protocol (1.1), F(1, 24)= 24.143, p < .001. CONCLUSIONS: The findings indicated that the picture activity schedule protocol may elicit better motor skill performance on the MABC-2 by children with ASD. We suggest researchers and practitioners incorporate a picture activity schedule into the MABC-2 assessment protocol when examining the fine and gross motor performance of children with ASD.

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7. Memari AH, Ghanouni P, Shayestehfar M, Ziaee V, Moshayedi P. {{Effects of visual search vs. auditory tasks on postural control in children with autism spectrum disorder}}. {Gait Posture};2013 (Aug 6)

Recent research in motor control shows the interactive role of cognitive factors in postural control. However, there is little understanding in how children with autism spectrum disorder (ASD) develop their postural behaviors. This study compares the interference of visual or auditory tasks on postural control in children with ASD. We examined 19 children with ASD (10-15 years old) and also 28 age-matched typically developing (TD) children. They were asked to perform two tasks during postural control: (1) a visual searching task (2) an auditory digit span task. Postural performances were measured with a force platform. Results showed that children with ASD indicated higher postural sway scores in visual task vs. auditory task; as root mean square (p=0.04), mean velocity (p=0.01) and sway area (p=0.02) but TD children scores remained unchanged. Children with ASD also showed significantly higher sway scores than TD children in all parameters. We conclude that in addition to primary differences in patterns of postural control of children with ASD compared to TD children, visual and auditory tasks may differently influence the postural control in this population.

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8. Menashe I, Grange P, Larsen EC, Banerjee-Basu S, Mitra PP. {{Co-expression Profiling of Autism Genes in the Mouse Brain}}. {PLoS Comput Biol};2013 (Jul);9(7):e1003128.

Autism spectrum disorder (ASD) is one of the most prevalent and highly heritable neurodevelopmental disorders in humans. There is significant evidence that the onset and severity of ASD is governed in part by complex genetic mechanisms affecting the normal development of the brain. To date, a number of genes have been associated with ASD. However, the temporal and spatial co-expression of these genes in the brain remain unclear. To address this issue, we examined the co-expression network of 26 autism genes from AutDB (http://mindspec.org/autdb.html), in the framework of 3,041 genes whose expression energies have the highest correlation between the coronal and sagittal images from the Allen Mouse Brain Atlas database (http://mouse.brain-map.org). These data were derived from in situ hybridization experiments conducted on male, 56-day old C57BL/6J mice co-registered to the Allen Reference Atlas, and were used to generate a normalized co-expression matrix indicating the cosine similarity between expression vectors of genes in this database. The network formed by the autism-associated genes showed a higher degree of co-expression connectivity than seen for the other genes in this dataset (Kolmogorov-Smirnov P = 5×10(-28)). Using Monte Carlo simulations, we identified two cliques of co-expressed genes that were significantly enriched with autism genes (A Bonferroni corrected P<0.05). Genes in both these cliques were significantly over-expressed in the cerebellar cortex (P = 1×10(-5)) suggesting possible implication of this brain region in autism. In conclusion, our study provides a detailed profiling of co-expression patterns of autism genes in the mouse brain, and suggests specific brain regions and new candidate genes that could be involved in autism etiology.

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9. Roelofs RL, Visser EM, Berger HJ, Prins JB, Van Schrojenstein Lantman-De Valk HM, Teunisse JP. {{Executive functioning in individuals with intellectual disabilities and autism spectrum disorders}}. {J Intellect Disabil Res};2013 (Aug 11)

BACKGROUND: Executive functioning (EF) is important for adequate behavioural functioning and crucial for explaining symptoms of autism spectrum disorders (ASD) in individuals with normal intelligence, but is scarcely studied in individuals with ASD and intellectual disabilities (ID). We therefore study EF in an ID population by comparing performances on three frequently studied executive functions (shifting, inhibition and updating) between individuals with ASD and individuals without ASD. When studying ID populations, one should be aware of Spearman’s Law of Diminishing Returns (SLODR), as it questions the possibility of measuring separate cognitive functions in ID populations. METHODS: Six EF tasks were administered to 50 individuals with mild to borderline ID, of which half was diagnosed with ASD. In order to investigate the distinctness of the three executive functions in this ID sample, the results on the six EF tasks were subjected to principal components analysis (PCA). Subsequently, a multivariate analysis of variance (MANOVA) was performed to assess differences between the ASD and non-ASD group on shifting, inhibition and updating. RESULTS: The PCA revealed the hypothesised EF trichotomy. MANOVA analysis showed no significant group differences on EF-performance. CONCLUSIONS: Three separate executive functions were measured in this ID population, but despite much evidence that individuals with ASD display more behavioural problems and the proven relevance of EF in behavioural functioning, no significant group difference was found on shifting, inhibition or updating. After this first effort to achieve more insight into EF of individuals with ASD and ID the relation between behavioural problems and EF will require further study.

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10. Ruiz Robledillo N, Gonzalez Bono E, Moya Albiol L. {{Lack of Institutional Support Entails Disruption in Cortisol Awakening Response in Caregivers of People with High-Functioning Autism}}. {J Health Psychol};2013 (Aug 9)

Several studies have found disruptions in cortisol awakening response in informal caregivers. Institutional support may modulate these effects, and this study analyses how the health of caregivers is affected when institutional support is provided for families of people with high-functioning autism. Self-reported health, depression and cortisol awakening response were analysed in three groups: supported caregivers, non-supported caregivers and non-caregivers. Non-supported caregivers presented higher somatic symptoms and lower cortisol awakening response than the supported caregiver and non-caregiver groups. A high number of somatic symptoms and low functionality of offspring were related to a lower cortisol awakening response only in the non-supported caregiver group. These findings demonstrate the importance of institutional support for improving the health of caregivers.

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11. Stam AJ, Schothorst PF, Vorstman JA, Staal WG. {{The genetic overlap of attention deficit hyperactivity disorder and autistic spectrum disorder}}. {Appl Clin Genet};2013;2:7-13.

Autistic spectrum disorders (ASD) and attention deficit hyperactivity disorder (ADHD) are classified as distinct disorders within the DSM-IV-TR (1994). The manual excludes simultaneous use of both diagnoses in case of overlap on a symptomatic level. However this does not always represent clinical observations and findings of previous studies. This review explores the genetic basis of the phenomenological overlap between ADHD and ASD. Based on an extensive review of twin-, linkage-, association studies, and reported structural genomic abnormalities associated with these disorders, we have identified seventeen regions on the human genome that can be related to both disorders. These regions of shared genetic association are: 2q35, 3p14, 4p16.1, 4p16.3, 5p15.31, 5p15.33, 7p12.3, 7p22, 7q21, 8q24.3, 14q12, 15q11-12, 16p13, 17q11, 18q21-23, 22q11.2, Xp22.3. The presented data are of interest for future genetic studies and appear to suggest the existence of a phenotype partition that may differ from the current classification of psychiatric disorders.

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12. Stroganova TA, Kozunov VV, Posikera IN, Galuta IA, Gratchev VV, Orekhova EV. {{Abnormal Pre-Attentive Arousal in Young Children with Autism Spectrum Disorder Contributes to Their Atypical Auditory Behavior: An ERP Study}}. {PLoS One};2013;8(7):e69100.

Auditory sensory modulation difficulties and problems with automatic re-orienting to sound are well documented in autism spectrum disorders (ASD). Abnormal preattentive arousal processes may contribute to these deficits. In this study, we investigated components of the cortical auditory evoked potential (CAEP) reflecting preattentive arousal in children with ASD and typically developing (TD) children aged 3-8 years. Pairs of clicks (‘S1’ and ‘S2’) separated by a 1 sec S1-S2 interstimulus interval (ISI) and much longer (8-10 sec) S1-S1 ISIs were presented monaurally to either the left or right ear. In TD children, the P50, P100 and N1c CAEP components were strongly influenced by temporal novelty of clicks and were much greater in response to the S1 than the S2 click. Irrespective of the stimulation side, the ‘tangential’ P100 component was rightward lateralized in TD children, whereas the ‘radial’ N1c component had higher amplitude contralaterally to the stimulated ear. Compared to the TD children, children with ASD demonstrated 1) reduced amplitude of the P100 component under the condition of temporal novelty (S1) and 2) an attenuated P100 repetition suppression effect. The abnormalities were lateralized and depended on the presentation side. They were evident in the case of the left but not the right ear stimulation. The P100 abnormalities in ASD correlated with the degree of developmental delay and with the severity of auditory sensory modulation difficulties observed in early life. The results suggest that some rightward-lateralized brain networks that are crucially important for arousal and attention re-orienting are compromised in children with ASD and that this deficit contributes to sensory modulation difficulties and possibly even other behavioral deficits in ASD.

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13. Won H, Mah W, Kim E. {{Autism spectrum disorder causes, mechanisms, and treatments: focus on neuronal synapses}}. {Front Mol Neurosci};2013;6:19.

Autism spectrum disorder (ASD) is a group of developmental disabilities characterized by impairments in social interaction and communication and restricted and repetitive interests/behaviors. Advances in human genomics have identified a large number of genetic variations associated with ASD. These associations are being rapidly verified by a growing number of studies using a variety of approaches, including mouse genetics. These studies have also identified key mechanisms underlying the pathogenesis of ASD, many of which involve synaptic dysfunctions, and have investigated novel, mechanism-based therapeutic strategies. This review will try to integrate these three key aspects of ASD research: human genetics, animal models, and potential treatments. Continued efforts in this direction should ultimately reveal core mechanisms that account for a larger fraction of ASD cases and identify neural mechanisms associated with specific ASD symptoms, providing important clues to efficient ASD treatment.

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14. Zablotsky B, Waldman HB, Zablotsky N, Perlman S. {{Dental health of children with autism spectrum disorders: a population-based study}}. {Alpha Omegan};2012 (Spring-Summer);105(1-2):22-26.

Data from the 2007 National Survey of Children’s Health were used to investigate how autism spectrum disorder (ASD) symptom severity and comorbidity are associated with the dental health needs of children. The results of this study help provide insights into the greater oral needs of the increasing population of children with ASD that reside in our communities and their dependency upon local practitioners for treatment.

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