1. Apicella F, Sicca F, Federico RR, Campatelli G, Muratori F. {{Fusiform Gyrus responses to neutral and emotional faces in children with Autism Spectrum Disorders: a High Density ERP study}}. {Behav Brain Res};2012 (Oct 31)
Face processing is a neural mechanism that allows understanding social information and cues conveyed by faces, whose dysfunction has been postulated to underlie some of the behavioral impairments characterizing Autism Spectrum Disorders (ASD). A special region of the cortex, the Fusiform Gyrus (FG), is believed to be the specific area for processing face features and emotions. However, behavioral, fMRI and ERP studies addressed to investigate the role of FG dysfunction in ASD have led to conflicting results. Using a high-density EEG system, we recorded the face-sensitive ERP to neutral and emotional (happiness and fearful) faces, as a measure of early activity of the FG, in children with high functioning ASD. By controlling a number of experimental and clinical variables that could have biased previous research – such as gaze direction, attention to tasks, stimulus appearance and clinical profiles – we aimed to assess the effective role of the FG in the face emotion processing deficit hypothesized in ASD. No significant differences in early face-sensitive ERP components were found between ASD and neurotypical children. However, a systematic latency delay and amplitude reduction of all early potentials were observed in the ASD group, regardless of the stimulus, although more evident for emotions. Therefore, we can assume a diffuse dysfunction of neural mechanisms and networks in driving and integrating social information conveyed by faces, in particular when emotions are involved, rather than a specific impairment of the FG-related face processing circuit. Nevertheless, there is need of further investigation.
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2. Demurie E, Roeyers H, Baeyens D, Sonuga-Barke E. {{Temporal discounting of monetary rewards in children and adolescents with ADHD and autism spectrum disorders}}. {Dev Sci};2012 (Nov);15(6):791-800.
It has been difficult to differentiate attention-deficit/hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) in terms of some aspects of their cognitive profile. While both show deficits in executive functions, it has been suggested that they may differ in their response to monetary reward. For instance, children with ADHD prefer small immediate over large delayed rewards more than typically developing controls. One explanation for this is that they discount the value of rewards to a higher degree as they are moved into the future. The current study investigated whether children with ADHD can be differentiated from those with ASD in terms of reward discounting. Thirty-nine children (8-16 y) with ADHD, 34 children with ASD and 46 typically developing controls performed a hypothetical monetary temporal discounting task. Participants were instructed to make repeated choices between small variable rewards (0, 5, 10, 20, 30euro) delivered immediately and large rewards delivered after a variable delay. Children with ADHD but not ASD discounted future rewards at a higher rate than typically developing controls. These data confirm steeper discounting of future rewards in ADHD and add to a small but growing literature showing that the psychological profile of ADHD can be distinguished from that of ASD in terms of disrupted motivational processes.
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3. Doherty-Sneddon G, Whittle L, Riby DM. {{Gaze aversion during social style interactions in autism spectrum disorder and Williams syndrome}}. {Res Dev Disabil};2012 (Oct 31);34(1):616-626.
During face-to-face interactions typically developing individuals use gaze aversion (GA), away from their questioner, when thinking. GA is also used when individuals with autism (ASD) and Williams syndrome (WS) are thinking during question-answer interactions. We investigated GA strategies during face-to-face social style interactions with familiar and unfamiliar interlocutors. Participants with WS and ASD used overall typical amounts/patterns of GA with all participants looking away most while thinking and remembering (in contrast to listening and speaking). However there were a couple of specific disorder related differences: participants with WS looked away less when thinking and interacting with unfamiliar interlocutors; in typical development and WS familiarity was associated with reduced gaze aversion, however no such difference was evident in ASD. Results inform typical/atypical social and cognitive phenotypes. We conclude that gaze aversion serves some common functions in typical and atypical development in terms of managing the cognitive and social load of interactions. There are some specific idiosyncracies associated with managing familiarity in ASD and WS with elevated sociability with unfamiliar others in WS and a lack of differentiation to interlocutor familiarity in ASD. Regardless of the familiarity of the interlocutor, GA is associated with thinking for typically developing as well as atypically developing groups. Social skills training must take this into account.
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4. Gadow KD, Devincent CJ, Siegal VI, Olvet DM, Kibria S, Kirsch SF, Hatchwell E. {{Allele-Specific Associations of 5-HTTLPR/rs25531 with ADHD and Autism Spectrum Disorder}}. {Prog Neuropsychopharmacol Biol Psychiatry};2012 (Oct 31)
BACKGROUND: The aims of the present study were to examine the association between a common serotonin transporter gene (SLC6A4) polymorphism 5-HTTLPR/rs25531 with severity of attention-deficit hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) symptoms. METHODS: Mothers and teachers completed a validated DSM-IV-referenced rating scale for ADHD and ASD symptoms in 118 children with ASD. RESULTS: Analyses indicated that children with at least one copy of the S or L(G) allele obtained significantly more severe maternal ratings of hyperactivity (p=0.001; etap(2)=0.097) and impulsivity (p=0.027; etap(2)=0.044) but not inattention (p=0.061; etap(2)=0.032), controlling for ASD severity, than children homozygous for the L(A) allele. Conversely, mothers’ ratings indicated that children with L(A)/L(A) genotype had more severe ASD social deficits than S+or L(G) allele carriers (p=0.003; etap(2)=0.081), controlling for ADHD symptom severity. Teachers’ ratings though consistent with mothers’ ratings of hyperactivity and social deficits were marginally significant (p=0.07/p=0.09). There was some evidence that the magnitude of parent-teacher agreement regarding symptom severity varied as a function of the child’s genotype. CONCLUSION: The 5-HTTLPR/rs25531 polymorphism or its correlates may modulate severity of ADHD and ASD symptoms in children with ASD, but in different ways. These tentative, hypothesis-generating findings require replication with larger independent samples.
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5. Hoffman K, Kalkbrenner AE, Vieira VM, Daniels JL. {{The spatial distribution of known predictors of autism spectrum disorders impacts geographic variability in prevalence in central North Carolina}}. {Environ Health};2012 (Oct 31);11(1):80.
ABSTRACT: BACKGROUND: The causes of autism spectrum disorders (ASD) remain largely unknown and widely debated; however, evidence increasingly points to the importance of environmental exposures. A growing number of studies use geographic variability in ASD prevalence or exposure patterns to investigate the association between environmental factors and ASD. However, differences in the geographic distribution of established risk and predictive factors for ASD, such as maternal education or age, can interfere with investigations of ASD etiology. We evaluated geographic variability in the prevalence of ASD in central North Carolina and the impact of spatial confounding by known risk and predictive factors. METHODS: Children meeting a standardized case definition for ASD at 8 years of age were identified through records-based surveillance for 8 counties biennially from 2002 to 2008 (n=532). Vital records were used to identify the underlying cohort (15% random sample of children born in the same years as children with an ASD, n=11,034), and to obtain birth addresses. We used generalized additive models (GAMs) to estimate the prevalence of ASD across the region by smoothing latitude and longitude. GAMs, unlike methods used in previous spatial analyses of ASD, allow for extensive adjustment of individual-level risk factors (e.g. maternal age and education) when evaluating spatial variability of disease prevalence. RESULTS: Unadjusted maps revealed geographic variation in surveillance-recognized ASD. Children born in certain regions of the study area were up to 1.27 times as likely to be recognized as having ASD compared to children born in the study area as a whole (prevalence ratio (PR) range across the study area 0.57-1.27; global P=0.003). However, geographic gradients of ASD prevalence were attenuated after adjusting for spatial confounders (adjusted PR range 0.72-1.12 across the study area; global P=0.052). CONCLUSIONS: In these data, spatial variation of ASD in central NC can be explained largely by factors impacting diagnosis, such as maternal education, emphasizing the importance of adjusting for differences in the geographic distribution of known individual-level predictors in spatial analyses of ASD. These results underscore the critical importance of accounting for such factors in studies of environmental exposures that vary across regions.
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6. Kaga M. {{Exploring autism research collaboration between Japan and United States Joint Academic Conference on Autism Spectrum Disorders, December, 2011}}. {Brain Dev};2012 (Oct 26)
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7. Kim ES, Berkovits LD, Bernier EP, Leyzberg D, Shic F, Paul R, Scassellati B. {{Social Robots as Embedded Reinforcers of Social Behavior in Children with Autism}}. {J Autism Dev Disord};2012 (Oct 31)
In this study we examined the social behaviors of 4- to 12-year-old children with autism spectrum disorders (ASD; N = 24) during three tradic interactions with an adult confederate and an interaction partner, where the interaction partner varied randomly among (1) another adult human, (2) a touchscreen computer game, and (3) a social dinosaur robot. Children spoke more in general, and directed more speech to the adult confederate, when the interaction partner was a robot, as compared to a human or computer game interaction partner. Children spoke as much to the robot as to the adult interaction partner. This study provides the largest demonstration of social human-robot interaction in children with autism to date. Our findings suggest that social robots may be developed into useful tools for social skills and communication therapies, specifically by embedding social interaction into intrinsic reinforcers and motivators.
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8. Ming X, Stein TP, Barnes V, Rhodes N, Guo L. {{Metabolic Perturbance in Autism Spectrum Disorders: A Metabolomics Study}}. {J Proteome Res};2012 (Oct 29)
Autism spectrum disorders (ASD) are a group of biological disorders with associated metabolic derangement. This study aimed to identify a pattern of metabolic perturbance in ASD using metabolomics in urinary specimens from 48 children with ASD and 53 age matched controls. Using a combination of liquid- and gas-chromatography-based mass spectrometry, we detected the levels of 82 metabolites (53 of which were increased) that were significantly altered between the ASD and the control groups using osmolality normalized data. Pattern analysis showed that the levels of several amino acids such as glycine, serine, threonine, alanine, histidine, glutamyl amino acids and the organic acid, taurine were significantly (p</=0.05) lower in ASD children. The levels of antioxidants such as carnosine were also reduced in ASD (p=0.054). Furthermore, several gut bacterial metabolites were significantly altered in ASD children who had gastrointestinal dysfunction. Overall, this study detected abnormal amino acid metabolism, increased oxidative stress, and altered gut microbiomes in ASD. The relationship of altered gut microbial co-metabolism and the disrupted metabolisms requires further investigation.
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9. Ni Chuileann S, Quigley J. {{Assessing Recollection and Familiarity in Low Functioning Autism}}. {J Autism Dev Disord};2012 (Oct 30)
Methods to assess recollection and familiarity separately in autism spectrum disorder were recently developed and piloted (Bigham et al. in J Autism Dev Disord 40:878-889, 2010). The preliminary data obtained via these methods showed that whereas recollection was mildly impaired in high functioning autism, familiarity was spared. The current study set out to replicate the methods of assessment for recollection and familiarity devised by Bigham and her colleagues with individuals diagnosed with low functioning autism (LFA). Three critical modifications to the original paradigms were made within the current study. The modifications and implications of the findings for individuals with LFA will be discussed.
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10. Oppenheim D, Koren-Karie N, Dolev S, Yirmiya N. {{Maternal sensitivity mediates the link between maternal insightfulness/resolution and child-mother attachment: the case of children with Autism Spectrum Disorder}}. {Attach Hum Dev};2012 (Nov);14(6):567-584.
This study examined the hypothesis that maternal sensitivity mediates the association between maternal Insightfulness/Resolution and child attachment in a sample of preschool age boys with Autism Spectrum Disorders. This study used the Insightfulness Assessment to assess insightfulness and the Reaction to Diagnosis Interview to assess mothers’ resolution. Maternal sensitivity was assessed from mother-child play observations, and the security of children’s attachment was assessed using the Strange Situation Procedure. The results supported the mediation model, and their implications for attachment research, research on intervention in autism, and clinical work are discussed.
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11. Pushker N, Tinwala S, Khurana S, Sen S. {{Bilateral microphthalmos with unilateral superior cyst in a child with autism and CHARGE syndrome}}. {Int Ophthalmol};2012 (Oct 31)
A case of autism with CHARGE syndrome with microphthalmos and a superior colobomatous cyst arising from the optic disc is reported. A 7-year-old boy presented with a gradually increasing mass, involving the superior orbit and upper eyelid of right eye of 3 years’ duration. Clinical examination revealed bilateral microphthalmos with typical iris coloboma, posterior synechiae, and cataractous lens. Imaging revealed bilateral optic disc colobomas with a superior cyst in the right orbit. Intraoperatively, a single cystic lesion was seen in the superior orbit arising from the optic disc region. Histopathology was suggestive of a colobomatous cyst, positive for glial tissue [glial fibrillary acidic protein (GFAP) positive] and neuroretinal elements (synaptophysin positive) on immunohistochemistry. Genetic analysis revealed a normal karyotype (46, XY).
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12. Souchay C, Wojcik DZ, Williams HL, Crathern S, Clarke P. {{Recollection in adolescents with Autism Spectrum Disorder}}. {Cortex};2012 (Sep 27)
INTRODUCTION: Autism Spectrum Disorder (ASD) is a neurodevelopmental disorder primarily affecting social interaction and communication. Recently, there has been interest in whether people with ASD also show memory deficits as a result of abnormal brain development. However, at least in adolescents with ASD, the recollection component of episodic memory has rarely been explored. This paper is an evaluation of recollection in three different experiments in adolescents with ASD, using both objective (source discrimination) and subjective methods (Remember-Know judgments). METHODS: Three experiments were designed to measure different aspects of contextual information: sensory/perceptual information (Experiment 1), temporal information (Experiment 2) and spatial information (Experiment 3). To measure objective and subjective recollection, for all three experiments, all participants were presented with information to learn in a specific context. At the recognition stage, they were asked whether they remembered the information or just knew the information was there (R/K response, subjective method). To assess the quality of these subjective judgments, participants justified their Remember responses using the contextual information. After the recognition task, to assess source memory (objective measure), all items presented at encoding were represented and participants have to recall the source for all these items. RESULTS: All three experiments showed that adolescents with ASD could correctly recall source information. However, in the first experiment adolescents with ASD gave significantly fewer Remember responses than controls. CONCLUSIONS: These findings point to a specific and subtle recollection impairment in adolescents with ASD, at least when subjective methods are used. We discuss how these might relate to differences in the self and to the brain abnormalities in ASD.
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13. Vanvuchelen M, Van Schuerbeeck L, Roeyers H, De Weerdt W. {{Understanding the mechanisms behind deficits in imitation: Do individuals with autism know ‘what’ to imitate and do they know ‘how’ to imitate?}}. {Res Dev Disabil};2012 (Oct 31);34(1):538-545.
Although imitation problems have been associated with autism for many years, the underlying mechanisms of these problems remain subject to debate. In this article, the question whether imitation problems are caused by selection or correspondence problems is explored and discussed. This review revealed that hypotheses on the nature of imitation problems in autism are complicated and inconclusive at the present time. There is some evidence for impaired selection, especially implicating poor preferential attention to biological motion and poor ascription of intention to action. There is also some evidence that both transformations of perspectives and mapping of visual to motor information are impaired, characterized as correspondence problems. However, it is not yet clear how poor selection processes contribute to correspondence problems and vice versa. Insight in this interaction may provide a valuable contribution to our understanding of imitation problems in autism. For further research we recommend that tasks should be constrained to target as few mechanisms as possible in given experiments.
