1. Backer van Ommeren T, Koot HM, Scheeren AM, Begeer S. {{Reliability and Validity of the Interactive Drawing Test: A Measure of Reciprocity for Children and Adolescents with Autism Spectrum Disorder}}. {J Autism Dev Disord}. 2015.
Poor reciprocity is a defining feature of an autism spectrum disorder (ASD). In the current study, we examined the reliability and validity of the Interactive Drawing Test (IDT), a new instrument to assess reciprocal behavior. The IDT was administered to children and adolescents with ASD (n = 131) and to a typically developing group (n = 62). The IDT had excellent inter-rater reliability and moderate to good test-retest reliability. The results showed clearly distinctive response patterns in the ASD group compared to the typically developing group, independent of verbal IQ and age. Convergent validity of the IDT was low. Sensitivity and the predictive accuracy of the IDT for detailed levels of reciprocal behavior in autism are discussed.
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2. Benjamin DP, McDuffie AS, Thurman AJ, Kover ST, Mastergeorge AM, Hagerman RJ, Abbeduto L. {{Effect of Speaker Gaze on Word Learning in Fragile X Syndrome: A comparison with nonsyndromic ASD}}. {J Speech Lang Hear Res}. 2015.
Purpose: This study examined use of a speaker’s direction of gaze during word learning by boys with fragile X syndrome (FXS), nonsyndromic autism spectrum disorder (ASD), and typical development (TD). Method: A fast-mapping task with Follow-In and Discrepant Labeling conditions was administered. Use of speaker gaze was expected to lead to selecting as the referent of the novel label the object to which the participant attended in Follow-In Trials and the object to which the examiner attended in the Discrepant Labeling Trials. Participants were school-aged boys with FXS (n = 18) or ASD (n = 18) matched on age, IQ, and nonverbal cognition and younger TD boys (n = 18) matched on nonverbal cognition. Results: All groups performed above chance in both conditions, although the TD boys performed closest to the expected pattern. Boys with FXS performed better during Follow-In than in Discrepant Label trials, whereas TD boys and boys with ASD did equally well in both trial types. The type of trial administered first influenced subsequent responding. Error patterns also distinguished the groups. Conclusions: The ability to utilize a speaker’s gaze during word learning is not as well developed in boys with FXS or nonsyndromic ASD as in TD children of the same developmental level.
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3. Braida D, Guerini FR, Ponzoni L, Corradini I, De Astis S, Pattini L, Bolognesi E, Benfante R, Fornasari D, Chiappedi M, Ghezzo A, Clerici M, Matteoli M, Sala M. {{Association between SNAP-25 gene polymorphisms and cognition in autism: functional consequences and potential therapeutic strategies}}. {Transl Psychiatry}. 2015; 5: e500.
Synaptosomal-associated protein of 25 kDa (SNAP-25) is involved in different neuropsychiatric disorders, including schizophrenia and attention-deficit/hyperactivity disorder. Consistently, SNAP-25 polymorphisms in humans are associated with hyperactivity and/or with low cognitive scores. We analysed five SNAP-25 gene polymorphisms (rs363050, rs363039, rs363043, rs3746544 and rs1051312) in 46 autistic children trying to correlate them with Childhood Autism Rating Scale and electroencephalogram (EEG) abnormalities. The functional effects of rs363050 single-nucleotide polymorphism (SNP) on the gene transcriptional activity, by means of the luciferase reporter gene, were evaluated. To investigate the functional consequences that SNAP-25 reduction may have in children, the behaviour and EEG of SNAP-25(+/-) adolescent mice (SNAP-25(+/+)) were studied. Significant association of SNAP-25 polymorphism with decreasing cognitive scores was observed. Analysis of transcriptional activity revealed that SNP rs363050 encompasses a regulatory element, leading to protein expression decrease. Reduction of SNAP-25 levels in adolescent mice was associated with hyperactivity, cognitive and social impairment and an abnormal EEG, characterized by the occurrence of frequent spikes. Both EEG abnormalities and behavioural deficits were rescued by repeated exposure for 21 days to sodium salt valproate (VLP). A partial recovery of SNAP-25 expression content in SNAP-25(+/-) hippocampi was also observed by means of western blotting. A reduced expression of SNAP-25 is responsible for the cognitive deficits in children affected by autism spectrum disorders, as presumably occurring in the presence of rs363050(G) allele, and for behavioural and EEG alterations in adolescent mice. VLP treatment could result in novel therapeutic strategies.
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4. Chien HY, Lin HY, Lai MC, Gau SS, Tseng WY. {{Hyperconnectivity of the Right Posterior Temporo-parietal Junction Predicts Social Difficulties in Boys with Autism Spectrum Disorder}}. {Autism Res}. 2015.
The posterior right temporo-parietal junction (pRTPJ) is a key brain region representing other’s mental status. Despite reports of atypical activation at pRTPJ during mentalizing in individuals with autism spectrum disorder (ASD), the intrinsic functional connectivity (iFC) of the pRTPJ remains under-investigated. We examined whether boys with ASD show altered resting-state iFC of the pRTPJ, and whether atypical iFC of the pRTPJ is associated with social deficits in ASD in a sample of 40 boys with high-functioning ASD (aged 9-17 years, mean age, 12.38 +/- 2.17; mean IQ, 105.60 +/- 16.06) and 42 typically developing (TD) boys (aged 9-17 years, mean age, 11.64 +/- 2.71; mean IQ, 111.29 +/- 13.45). Both groups received resting-state fMRI assessment after imaging data quality control for in-scanner head motion and spatial coverage. Seed-based approach was used to investigate iFC of the pRTPJ. TD and ASD boys demonstrated a resting-state pRTPJ iFC pattern comparable to the known spatial involvement of the default-mode network. Boys with ASD showed pRTPJ hyperconnectivity relative to TD boys in the right ventral occipito-temporal cortex. This atypically increased iFC in the ASD group was positively correlated with social deficits assessed by the Chinese version of the Autism Diagnostic Interview-Revised and the Social Responsive Scale. Our findings provide empirical support for functional « dysconnectivity, » that is, atypical functional integration among brain regions, as an integral component of the atypical neurobiology of ASD. Autism Res 2015. (c) 2015 International Society for Autism Research, Wiley Periodicals, Inc.
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5. Coster WJ, Kramer JM, Tian F, Dooley M, Liljenquist K, Kao YC, Ni P. {{Evaluating the appropriateness of a new computer-administered measure of adaptive function for children and youth with autism spectrum disorders}}. {Autism}. 2015.
The Pediatric Evaluation of Disability Inventory-Computer Adaptive Test is an alternative method for describing the adaptive function of children and youth with disabilities using a computer-administered assessment. This study evaluated the performance of the Pediatric Evaluation of Disability Inventory-Computer Adaptive Test with a national sample of children and youth with autism spectrum disorders aged 3-21 years. Parents (n = 365) completed an online survey that included demographics, the Social Communication Questionnaire, and the Pediatric Evaluation of Disability Inventory-Computer Adaptive Test Social/Cognitive, Daily Activities, and Responsibility domains. Item response theory analysis confirmed items in each domain fit a unidimensional model and few items misfit. A large number of items in the Social/Cognitive domain showed differential item functioning, indicating a unique order of item difficulty in this population in this domain. Differences in item difficulty estimates were addressed through a parameter linking (equating) process. Simulations supported the accuracy and precision of the Computer Adaptive Test. Results suggest that the Pediatric Evaluation of Disability Inventory-Computer Adaptive Test, as modified for autism spectrum disorder, is an efficient and sound assessment for this population.
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6. Eussen ML, Louwerse A, Herba CM, Van Gool AR, Verheij F, Verhulst FC, Greaves-Lord K. {{Childhood Facial Recognition Predicts Adolescent Symptom Severity in Autism Spectrum Disorder}}. {Autism Res}. 2015.
Limited accuracy and speed in facial recognition (FR) and in the identification of facial emotions (IFE) have been shown in autism spectrum disorders (ASD). This study aimed at evaluating the predictive value of atypicalities in FR and IFE for future symptom severity in children with ASD. Therefore we performed a seven-year follow-up study in 87 children with ASD. FR and IFE were assessed in childhood (T1: age 6-12) using the Amsterdam Neuropsychological Tasks (ANT). Symptom severity was assessed using the Autism Diagnostic Observation Schedule (ADOS) in childhood and again seven years later during adolescence (T2: age 12-19). Multiple regression analyses were performed to investigate whether FR and IFE in childhood predicted ASD symptom severity in adolescence, while controlling for ASD symptom severity in childhood. We found that more accurate FR significantly predicted lower adolescent ASD symptom severity scores (DeltaR2 = .09), even when controlling for childhood ASD symptom severity. IFE was not a significant predictor of ASD symptom severity in adolescence. From these results it can be concluded, that in children with ASD the accuracy of FR in childhood is a relevant predictor of ASD symptom severity in adolescence. Test results on FR in children with ASD may have prognostic value regarding later symptom severity. Autism Res 2015. (c) 2015 International Society for Autism Research, Wiley Periodicals, Inc.
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7. Gaigg SB, Bowler DM, Ecker C, Calvo-Merino B, Murphy DG. {{Episodic Recollection Difficulties in ASD Result from Atypical Relational Encoding: Behavioral and Neural Evidence}}. {Autism Res}. 2015.
Memory functioning in Autism Spectrum Disorder (ASD) is characterized by impairments in the encoding of relational but not item information and difficulties in the recollection of contextually rich episodic memories but not in the retrieval of relatively context-free memories through processes of familiarity. The neural underpinnings of this profile and the extent to which encoding difficulties contribute to retrieval difficulties in ASD remain unclear. Using a paradigm developed by Addis and McAndrews [2006; Neuroimage, 33, 1194-1206] we asked adults with and without a diagnosis of ASD to study word-triplets during functional Magnetic Resonance Imaging (fMRI) scanning that varied in the number of category relations amongst component words. Performance at test confirmed attenuated recollection in the context of preserved familiarity based retrieval in ASD. The results also showed that recollection but not familiarity based retrieval increases as a function of category relations in word triads for both groups, indicating a close link between the encoding of relational information and recollection. This link was further supported by the imaging results, where blood oxygen level dependent (BOLD) signal responses in overlapping regions of the inferior prefrontal cortex were sensitive to the relational encoding manipulation as well as the contrast between recollection versus familiarity based retrieval. Interestingly, however, there was no evidence of prefrontal signal differentiation for this latter contrast in the ASD group for whom signal changes in a left hippocampal region were also marginally attenuated. Together, these observations suggest that attenuated levels of episodic recollection in ASD are, at least in part, attributable to anomalies in relational encoding processes. Autism Res 2015. (c) 2015 International Society for Autism Research, Wiley Periodicals, Inc.
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8. Gholizadeh S, Halder SK, Hampson DR. {{Expression of fragile X mental retardation protein in neurons and glia of the developing and adult mouse brain}}. {Brain Res}. 2015; 1596: 22-30.
Fragile X syndrome is the most common inherited form of mental retardation and autism. It is caused by a reduction or elimination of the expression of fragile X mental retardation protein (FMRP). Because fragile X syndrome is a neurodevelopmental disorder, it is important to fully document the cell type expression in the developing CNS to provide a better understanding of the molecular function of FMRP, and the pathogenesis of the syndrome. We investigated FMRP expression in the brain using double-labeling immunocytochemistry and cell type markers for neurons (NeuN), astrocytes (S100beta), microglia (Iba-1), and oligodendrocyte precursor cells (NG2). The hippocampus, striatum, cingulate cortex, retrosplenial cortex, corpus callosum and cerebellum were assessed in wild-type C57/BL6 mice at postnatal days 0, 10, 20, and adult. Our results demonstrate that FMRP is ubiquitously expressed in neurons at all times and brain regions studied, except for corpus callosum where FMRP was predominantly present in astrocytes at all ages. FMRP expression in Iba-1 and NG2-positive cells was detected at postnatal day 0 and 10 and gradually decreased to very low or undetectable levels in postnatal day 20 and adult mice. Our results reveal that in addition to continuous and extensive expression in neurons in the immature and mature brain, FMRP is also present in astrocytes, oligodendrocyte precursor cells, and microglia during the early and mid-postnatal developmental stages of brain maturation. Prominent expression of FMRP in glia during these crucial stages of brain development suggests an important contribution to normal brain function, and in its absence, to the fragile X phenotype.
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9. Hutsler JJ, Casanova MF. {{Cortical Construction in Autism Spectrum Disorder: Columns, Connectivity and the Subplate}}. {Neuropathol Appl Neurobiol}. 2015.
The cerebral cortex undergoes protracted maturation during human development and exemplifies how biology and environment are inextricably intertwined in the construction of complex neural circuits. Autism spectrum disorders are characterized by a number of pathological changes arising from this developmental process. These include: (1) alterations to columnar structure that have significant implications for the organization of cortical circuits and connectivity; (2) alterations to synaptic spines on individual cortical units that may underlie specific types of connectional changes; and (3) alterations within the cortical subplate, a region that plays a role in proper cortical development and in regulating interregional communication in the mature brain. Although the cerebral cortex is not the only structure affected in the disorder, it is a fundamental contributor to the behaviors that characterize autism. These alterations to cortical circuitry likely underlie the behavioral phenotype in autism and contribute to the unique pattern of deficits and strengths that characterize cognitive functioning. Recent findings within the cortical subplate, may indicate that alterations to cortical construction begin prenatally, before activity dependent connections are established, and are in need of further study. A better understanding of cortical development in autism spectrum disorders will draw bridges between the microanatomical computational circuitry and the atypical behaviors that arise when that circuitry is modified. In addition, it will allow us to better exploit the constructional plasticity within the brain to design more targeted interventions that better manage atypical cortical construction and that can be applied very early in postnatal life.
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10. LaFlamme B. {{Genetic modules for autism}}. {Nat Genet}. 2015; 47(2): 105.
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11. Mazina V, Gerdts J, Trinh S, Ankenman K, Ward T, Dennis MY, Girirajan S, Eichler EE, Bernier R. {{Epigenetics of Autism-related Impairment: Copy Number Variation and Maternal Infection}}. {J Dev Behav Pediatr}. 2015.
OBJECTIVE:: Epidemiological data have suggested maternal infection and fever to be associated with increased risk of autism spectrum disorder (ASD). Animal studies show that gestational infections perturb fetal brain development and result in offspring with the core features of autism and have demonstrated that behavioral effects of maternal immune activation are dependent on genetic susceptibility. The goal of this study was to explore the impact of ASD-associated copy number variants (CNVs) and prenatal maternal infection on clinical severity of ASD within a dataset of prenatal history and complete genetic and phenotypic findings. METHODS:: We analyzed data from the Simons Simplex Collection sample including 1971 children with a diagnosis of ASD aged 4 to 18 years who underwent array comparative genomic hybridization screening. Information on infection and febrile episodes during pregnancy was collected through parent interview. ASD severity was clinically measured through parent-reported interview and questionnaires. RESULTS:: We found significant interactive effects between the presence of CNVs and maternal infection during pregnancy on autistic symptomatology, such that individuals with CNVs and history of maternal infection demonstrated increased rates of social communicative impairments and repetitive/restricted behaviors. In contrast, no significant interactions were found between presence of CNVs and prenatal infections on cognitive and adaptive functioning of individuals with ASD. CONCLUSIONS:: Our findings support a gene-environment interaction model of autism impairment, in that individuals with ASD-associated CNVs are more susceptible to the effects of maternal infection and febrile episodes in pregnancy on behavioral outcomes and suggest that these effects are specific to ASD rather than to global neurodevelopment.
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12. Mikita N, Hollocks MJ, Papadopoulos AS, Aslani A, Harrison S, Leibenluft E, Simonoff E, Stringaris A. {{Irritability in boys with autism spectrum disorders: an investigation of physiological reactivity}}. {J Child Psychol Psychiatry}. 2015.
BACKGROUND: Irritability in people with autism spectrum disorders (ASD) is common and impairing, yet its mechanisms remain understudied. We investigated symptom reporting and mechanisms of irritability in ASD, focusing on the relation between irritability and physiological stress responses. METHODS: Forty-seven unmedicated boys with high-functioning ASD (hfASD) and 23 typically developing boys aged 10-16 years completed a psychosocial stress test. Changes in cortisol, heart rate and heart rate variability throughout the test were recorded. Self- and parent-reported measures of irritability were obtained. Irritability symptom reporting in the hfASD group was compared to two groups of boys without ASD: highly irritable boys (severe mood dysregulation, SMD; n = 40) and healthy-control boys (HC; n = 30). RESULTS: Boys with hfASD scored significantly higher on irritability than HC boys, and they reported a pattern of irritability symptoms closely resembling that of boys with SMD. The internal consistency of irritability in hfASD was high by parent- and self-report. Although boys with hfASD showed significant stress-induced changes in cortisol and heart rate, those who rated themselves as highly irritable had lower cortisol levels throughout the test compared to those low on irritability. Participants rated as highly irritable by their parents showed blunted cortisol and heart rate responses to stress. The effects of irritability on heart rate, but not cortisol, were accounted for by trait anxiety. CONCLUSIONS: Irritability can be measured reliably in hfASD and is associated with distinct biological responses to stress.
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13. Mohammadi M, Zarafshan H. {{Family function, Parenting Style and Broader Autism Phenotype as Predicting Factors of Psychological Adjustment in Typically Developing Siblings of Children with Autism Spectrum Disorders}}. {Iran J Psychiatry}. 2014; 9(2): 55-63.
OBJECTIVE: Siblings of children with autism are at a greater risk of experiencing behavioral and social problems. Previous researches had focused on environmental variables such as family history of autism spectrum disorders (ASDs), behavior problems in the child with an ASD, parental mental health problems, stressful life events and « broader autism phenotype » (BAP), while variables like parenting style and family function that are shown to influence children’s behavioral and psychosocial adjustment are overlooked. The aim of the present study was to reveal how parenting style and family function as well as BAP effect psychological adjustment of siblings of children with autism. METHOD: The Participants included 65 parents who had one child with an Autism Spectrum Disorder and one typically developing child. Of the children with ASDs, 40 were boys and 25 were girls; and they were diagnosed with ASDs by a psychiatrist based on DSM-IV-TR criteria and Autism Diagnostic Interview-Revised (ADI-R). The Persian versions of the six scales were used to collect data from the families. Pearson’s correlation test and regression analysis were used to determine which variables were related to the psychological adjustment of sibling of children with ASDs and which variables predicted it better. RESULTS: Significant relationships were found between Strengths and Difficulties Questionnaire (SDQ) total difficulties, prosocial behaviors and ASDs symptoms severity, parenting styles and some aspects of family function. In addition, siblings who had more BAP characteristics had more behavior problems and less prosocial behavior. Behavioral problems increased and prosocial behavior decreased with permissive parenting style. Besides, both of authoritarian and authoritative parenting styles led to a decrease in behavioral problems and an increase in prosocial behaviors. Our findings revealed that some aspects of family function (affective responsiveness, roles, problem solving and behavior control) were significantly correlated with behavioral problems and prosocial behaviors in typically developing (TD) siblings of children with ASDs. CONCLUSION: Siblings of children with ASDs, due to genetic liability, are at a greater risk of psychological maladjustment. Furthermore, environmental factors like parenting styles and family function also have a significant effect on psychological maladjustment.
14. Ngounou Wetie AG, Wormwood KL, Russell S, Ryan JP, Darie CC, Woods AG. {{A Pilot Proteomic Analysis of Salivary Biomarkers in Autism Spectrum Disorder}}. {Autism Res}. 2015.
Autism spectrum disorder (ASD) prevalence is increasing, with current estimates at 1/68-1/50 individuals diagnosed with an ASD. Diagnosis is based on behavioral assessments. Early diagnosis and intervention is known to greatly improve functional outcomes in people with ASD. Diagnosis, treatment monitoring and prognosis of ASD symptoms could be facilitated with biomarkers to complement behavioral assessments. Mass spectrometry (MS) based proteomics may help reveal biomarkers for ASD. In this pilot study, we have analyzed the salivary proteome in individuals with ASD compared to neurotypical control subjects, using MS-based proteomics. Our goal is to optimize methods for salivary proteomic biomarker discovery and to identify initial putative biomarkers in people with ASDs. The salivary proteome is virtually unstudied in ASD, and saliva could provide an easily accessible biomaterial for analysis. Using nano liquid chromatography-tandem mass spectrometry, we found statistically significant differences in several salivary proteins, including elevated prolactin-inducible protein, lactotransferrin, Ig kappa chain C region, Ig gamma-1 chain C region, Ig lambda-2 chain C regions, neutrophil elastase, polymeric immunoglobulin receptor and deleted in malignant brain tumors 1. Our results indicate that this is an effective method for identification of salivary protein biomarkers, support the concept that immune system and gastrointestinal disturbances may be present in individuals with ASDs and point toward the need for larger studies in behaviorally-characterized individuals. Autism Res 2015. (c) 2015 International Society for Autism Research, Wiley Periodicals, Inc.
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15. Nicolini C, Ahn Y, Michalski B, Rho JM, Fahnestock M. {{Decreased mTOR signaling pathway in human idiopathic autism and in rats exposed to valproic acid}}. {Acta Neuropathol Commun}. 2015; 3(1): 3.
BACKGROUND: The molecular mechanisms underlying autistic behaviors remain to be elucidated. Mutations in genes linked to autism adversely affect molecules regulating dendritic spine formation, function and plasticity, and some increase the mammalian target of rapamycin, mTOR, a regulator of protein synthesis at spines. Here, we investigated whether the Akt/mTOR pathway is disrupted in idiopathic autism and in rats exposed to valproic acid, an animal model exhibiting autistic-like behavior. METHODS: Components of the mTOR pathway were assayed by Western blotting in postmortem fusiform gyrus samples from 11 subjects with idiopathic autism and 13 controls and in valproic acid versus saline-exposed rat neocortex. Additionally, protein levels of brain-derived neurotrophic factor receptor (TrkB) isoforms and the postsynaptic organizing molecule PSD-95 were measured in autistic versus control subjects. RESULTS: Full-length TrkB, PI3K, Akt, phosphorylated and total mTOR, p70S6 kinase, eIF4B and PSD-95 were reduced in autistic versus control fusiform gyrus. Similarly, phosphorylated and total Akt, mTOR and 4E-BP1 and phosphorylated S6 protein were decreased in valproic acid- versus saline-exposed rats. However, no changes in 4E-BP1 or eIF4E were found in autistic brains. CONCLUSIONS: In contrast to some monogenic disorders with high rates of autism, our data demonstrate down-regulation of the Akt/mTOR pathway, specifically via p70S6K/eIF4B, in idiopathic autism. These findings suggest that disruption of this pathway in either direction is widespread in autism and can have adverse consequences for synaptic function. The use of valproic acid, a histone deacetylase inhibitor, in rats successfully modeled these changes, implicating an epigenetic mechanism in these pathway disruptions.
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16. Osipowicz K, Bosenbark DD, Patrick KE. {{Cortical Changes Across the Autism Lifespan}}. {Autism Res}. 2015.
Although it is widely accepted that autism spectrum disorder (ASD) involves neuroanatomical abnormalities and atypical neurodevelopmental patterns, there is little consensus regarding the precise pattern of neuroanatomical differences or how these differences relate to autism symptomology. Furthermore, there is limited research related to neuroanatomical correlates of autism symptomology in individuals with ASD and the studies that do exist primarily include small samples. This study was the first to investigate gray matter (GM) changes throughout the ASD lifespan, using voxel-based morphometry to determine whether significant differences exist in the GM volumes of a large sample of individuals with ASD compared to age- and IQ-matched typical controls. We examined GM volume across the lifespan in 531 individuals diagnosed with ASD and 571 neurotypical controls, aged 7-64. We compared groups and correlated GM with age and autism severity in the ASD group. Findings suggest bilateral decreased GM volume for individuals with ASD in regions extending from the thalamus to the cerebellum, anterior medial temporal lobes, and orbitofrontal regions. Higher autism severity was associated with decreased GM volumes in prefrontal cortex, inferior parietal and temporal regions, and temporal poles. Similar relationships were found between GM volume and age. ASD diagnosis and severity were not associated with increased GM volumes in any region. Autism Res 2015. (c) 2015 International Society for Autism Research, Wiley Periodicals, Inc.
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17. Palmer CJ, Paton B, Kirkovski M, Enticott PG, Hohwy J. {{Context sensitivity in action decreases along the autism spectrum: a predictive processing perspective}}. {Proc Biol Sci}. 2015; 282(1802).
Recent predictive processing accounts of perception and action point towards a key challenge for the nervous system in dynamically optimizing the balance between incoming sensory information and existing expectations regarding the state of the environment. Here, we report differences in the influence of the preceding sensory context on motor function, varying with respect to both clinical and subclinical features of autism spectrum disorder (ASD). Reach-to-grasp movements were recorded subsequent to an inactive period in which illusory ownership of a prosthetic limb was induced. We analysed the sub-components of reach trajectories derived using a minimum-jerk fitting procedure. Non-clinical adults low in autistic features showed disrupted movement execution following the illusion compared to a control condition. By contrast, individuals higher in autistic features (both those with ASD and non-clinical individuals high in autistic traits) showed reduced sensitivity to the presence of the illusion in their reaching movements while still exhibiting the typical perceptual effects of the illusion. Clinical individuals were distinct from non-clinical individuals scoring high in autistic features, however, in the early stages of movement. These results suggest that the influence of high-level representations of the environment differs between individuals, contributing to clinical and subclinical differences in motor performance that manifest in a contextual manner. As high-level representations of context help to explain fluctuations in sensory input over relatively longer time scales, more circumscribed sensitivity to prior or contextual information in autistic sensory processing could contribute more generally to reduced social comprehension, sensory impairments and a stronger desire for predictability and routine.
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18. Pokorny JJ, Hatt NV, Colombi C, Vivanti G, Rogers SJ, Rivera SM. {{The Action Observation System when Observing Hand Actions in Autism and Typical Development}}. {Autism Res}. 2015.
Social impairments in individuals with autism spectrum disorders (ASD) may be in part due to difficulty perceiving and recognizing the actions of others. Evidence from imitation studies, which involves both observation and execution of an action, suggests differences, in individuals with ASD, between the ability to imitate goal-directed actions involving objects (transitive actions) and the ability to imitate actions that do not involve objects (intransitive actions). In the present study, we examined whether there were differences in how ASD adolescents encoded transitive and intransitive actions compared to typically developing (TD) adolescents, by having participants view videos of a hand reaching across a screen toward an object or to where an object would be while functional magnetic resonance images were collected. Analyses focused on areas within the action observation network (AON), which is activated during the observation of actions performed by others. We hypothesized that the AON would differentiate transitive from intransitive actions only in the ASD group. However, results revealed that object presence modulated activity in the right inferior frontal gyrus and supramarginal gyrus of the TD group, a differentiation that was not seen in the ASD group. Furthermore, there were no significant group differences between the TD and ASD groups in any of the conditions. This suggests that there is not a global deficit of the AON in individuals with ASD while observing transitive and intransitive actions. Autism Res 2015. (c) 2015 International Society for Autism Research, Wiley Periodicals, Inc.
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19. Postorino V, Fatta LM, De Peppo L, Giovagnoli G, Armando M, Vicari S, Mazzone L. {{Longitudinal comparison between male and female preschool children with autism spectrum disorder}}. {J Autism Dev Disord}. 2015.
Epidemiological studies have highlighted a strong male bias in autism spectrum disorder (ASD), however few studies have examined gender differences in autism symptoms, and available findings are inconsistent. The aim of the present study is to investigate the longitudinal gender differences in developmental profiles of 30 female and 30 male age-matched preschool children with ASD. All the children underwent a comprehensive evaluation at T0 and at T1. Our results have shown no significant interaction between time and gender for predicting autism symptoms, developmental quotient, parental stress, children’s adaptive skills and behavior problems. Shedding light on the developmental trajectories in ASD could help clinicians to recognize children with ASD at an earlier age and contribute to the development of appropriate treatments.
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20. Pruett JR, Jr., Kandala S, Petersen SE, Povinelli DJ. {{Brief Report: Theory of Mind, Relational Reasoning, and Social Responsiveness in Children With and Without Autism: Demonstration of Feasibility for a Larger-Scale Study}}. {J Autism Dev Disord}. 2015.
Understanding the underpinnings of social responsiveness and theory of mind (ToM) will enhance our knowledge of autism spectrum disorder (ASD). We hypothesize that higher-order relational reasoning (higher-order RR: reasoning necessitating integration of relationships among multiple variables) is necessary but not sufficient for ToM, and that social responsiveness varies independently of higher-order RR. A pilot experiment tested these hypotheses in n = 17 children, 3-14, with and without ASD. No child failing 2nd-order RR passed a false belief ToM test. Contrary to prediction, Social Responsiveness Scale scores did correlate with 2nd-order RR performance, likely due to sample characteristics. It is feasible to translate this comparative cognition-inspired line of inquiry for full-scale studies of ToM, higher-order RR, and social responsiveness in ASD.
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21. Rosenberg K. {{New reporting practices may explain increases in autism spectrum disorders}}. {Am J Nurs}. 2015; 115(2): 57.
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22. Stadnick NA, Stahmer A, Brookman-Frazee L. {{Preliminary Effectiveness of Project ImPACT: A Parent-Mediated Intervention for Children with Autism Spectrum Disorder Delivered in a Community Program}}. {J Autism Dev Disord}. 2015.
This is a pilot study of the effectiveness of Project ImPACT, a parent-mediated intervention for ASD delivered in a community program. The primary aim was to compare child and parent outcomes between the intervention group and a community comparison for 30 young children with ASD at baseline and 12 weeks. The secondary aim was to identify parent factors associated with changes in child outcomes. Results indicated significant improvement in child communication skills and a strong trend for parent intervention adherence for the intervention group from baseline to 12 weeks. Higher baseline parenting stress was negatively related to child social gains from baseline to 12 weeks. Findings provide further support for delivering parent-mediated interventions in community settings to children with ASD.
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23. Swain NR, Eadie PA, Prior MR, Reilly S. {{Assessing early communication skills at 12 months: a retrospective study of Autism Spectrum Disorder}}. {Int J Lang Commun Disord}. 2015.
BACKGROUND: Early identification of Autism Spectrum Disorder (ASD) is currently limited by the absence of reliable biological markers for the disorder, as well as the reliability of screening and assessment tools for children aged between 6 and 18 months. Ongoing research has demonstrated the importance of early social communication skills in differentiating children later diagnosed with ASD from their typically developing (TD) peers, but researchers have not yet investigated whether these differences can be detected using community-ascertained systematic observation data as early as 12 months. AIMS: To investigate whether differences in early social communication skills can be detected at 12 months of age, comparing children later diagnosed with ASD, and TD peers; and to determine whether differences remain when groupings are based on age of subsequent ASD diagnosis. METHODS & PROCEDURES: From a prospective community-ascertained sample, we collected data on children in early life, then conducted retrospective analyses for those children who were later diagnosed with ASD by the age of 7 years, compared with matched TD peers. We analysed standardized observational data of early communication skills, collected using the Communication and Symbolic Behavior Scales-Developmental Profile (CSBS-DP) Behavior Sample, when participants were 12 months of age. OUTCOMES & RESULTS: Children in the ASD group exhibited significantly lower social communication skills than the TD group, including on the Total score and Social and Symbolic Composite scores of the CSBS-DP Behavior Sample. Differences on the Total score and Social Composite were also detected for both early and late ASD diagnosis groups when compared with the TD group. CONCLUSIONS & IMPLICATIONS: These findings give further support for the importance of social communication in assessing children at risk of ASD as early as 12 months of age. Future research could evaluate the sensitivity and specificity of direct observation of these early communication skills as diagnostic indicators for ASD at 12 months, and investigate whether it is possible to distinguish between ASD and other high-risk groups (e.g. developmental delay) at this age.
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24. Szatmari P, Georgiades S, Duku E, Bennett TA, Bryson S, Fombonne E, Mirenda P, Roberts W, Smith IM, Vaillancourt T, Volden J, Waddell C, Zwaigenbaum L, Elsabbagh M, Thompson A. {{Developmental Trajectories of Symptom Severity and Adaptive Functioning in an Inception Cohort of Preschool Children With Autism Spectrum Disorder}}. {JAMA Psychiatry}. 2015.
Importance: Symptom severity and adaptive functioning are fundamental domains of the autism spectrum disorder (ASD) phenotype. To date, the longitudinal association between these 2 domains has not been examined. Objective: To describe the developmental trajectories of autistic symptom severity and adaptive functioning in a large inception cohort of preschool children with ASD. Design, Setting, and Participants: The sample consisted of 421 newly diagnosed preschool children with ASD 2 to 4 years old (355 boys; mean age at study enrollment, 39.87 months) participating in a large Canadian multisite longitudinal study (Pathways in ASD Study). Prospective data collected at 4 points from time of diagnosis to age 6 years were used to track the developmental trajectories of children. Main Outcomes and Measures: Autistic symptom severity was indexed using the Autism Diagnostic Observation Schedule. Adaptive functioning was indexed using the Vineland Adaptive Behavior Scales, Second Edition. Results: Two distinct trajectory groups provided the best fit to the autistic symptom severity data. Group 1 (11.4% of the sample) had less severe symptoms and an improving trajectory (P < .05), whereas group 2 (88.6% of the sample) had more severe symptoms and a stable trajectory. Three distinct trajectory groups provided the best fit to the adaptive functioning data. Group 1 (29.2% of the sample) showed lower functioning and a worsening trajectory, group 2 (49.9% of the sample) had moderate functioning and a stable trajectory, and group 3 (20.9% of the sample) had higher functioning and an improving trajectory (P < .05). Cross-trajectory overlap between the autistic symptom severity and adaptive functioning groups was low (phi = 0.13, P < .05). Sex was a significant predictor of autistic symptom severity group membership and age at diagnosis, and language and cognitive scores at baseline predicted membership in adaptive functioning trajectories. Trajectories of both symptom severity and adaptive functioning predicted several different outcomes at age 6 years. Conclusions and Relevance: Findings confirm the heterogeneous nature of developmental trajectories in ASD. Change in adaptive functioning suggests that improvement is possible in roughly 20% of the sample. Autistic symptom severity appears to be more stable, with roughly 11% of the sample showing a marked decrease in symptom severity. During the preschool years, there appears to be only a small amount of « yoking » of developmental trajectories in autistic symptom severity and adaptive functioning. It is imperative that a flexible suite of interventions that target both autistic symptom severity and adaptive functioning should be implemented and tailored to each child’s strengths and difficulties.
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25. Wong IC, Hsia Y. {{Authors’ response to Bachmann and Hoffman’s comments on psychopharmacological prescriptions for people with autism spectrum disorder (ASD): a multinational study}}. {Psychopharmacology (Berl)}. 2015.
