1. Adamson LB, Bakeman R, Deckner DF, Nelson PB. {{Rating Parent-Child Interactions: Joint Engagement, Communication Dynamics, and Shared Topics in Autism, Down Syndrome, and Typical Development}}. {J Autism Dev Disord};2012 (Mar 31)
A battery of 17 rating items were applied to video records of typically-developing toddlers and young children with autism and Down syndrome interacting with their parents during the Communication Play Protocol. This battery provided a reliable and broad view of the joint engagement triad of child, partner, and shared topic. Ratings of the child’s joint engagement correlated very strongly with state coding of joint engagement and replicated the finding that coordinated joint engagement was less likely in children with autism. Ratings of other child actions, of parent contributions, and of shared topics and communicative dynamics also documented pervasive variations related to diagnosis, language facility, and communicative context.
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2. Devlin B, Scherer SW. {{Genetic architecture in autism spectrum disorder}}. {Curr Opin Genet Dev};2012 (Mar 29)
Autism spectrum disorder (ASD) is characterized by impairments in reciprocal social interaction and communication, and by restricted and repetitive behaviors. Family studies indicate a significant genetic basis for ASD susceptibility, and genomic scanning is beginning to elucidate the underlying genetic architecture. Some 5-15% of individuals with ASD have an identifiable genetic etiology corresponding to known chromosomal rearrangements or single gene disorders. Rare (<1% frequency) de novo or inherited copy number variations (CNVs) (especially those that affect genes with synaptic function) are observed in 5-10% of idiopathic ASD cases. These findings, coupled with genome sequencing data suggest the existence of hundreds of ASD risk genes. Common variants, yet unidentified, exert only small effects on risk. Identification of ASD risk genes with high penetrance will broaden the targets amenable to genetic testing; while the biological pathways revealed by the deeper list of ASD genes should narrow the targets for therapeutic intervention.
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3. Gliga T, Elsabbagh M, Hudry K, Charman T, Johnson MH. {{Gaze Following, Gaze Reading, and Word Learning in Children at Risk for Autism}}. {Child Dev};2012 (Mar 29)
This study investigated gaze-following abilities as a prerequisite for word learning, in a population expected to manifest a wide range of social and communicative skills-children with a family history of autism. Fifty-three 3-year-olds with or without a family history of autism took part in a televised word-learning task. Using an eye-tracker to monitor children’s gaze behavior, it was shown that the ability to follow gaze was necessary but not sufficient for successful word learning. Those children who had poor social and communicative skills followed gaze to the labeled object but did not then learn the associated word. These findings shed light on the conditions that lead to successful word learning in typical and atypical populations.
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4. Jacot-Descombes S, Uppal N, Wicinski B, Santos M, Schmeidler J, Giannakopoulos P, Heinsein H, Schmitz C, Hof PR. {{Decreased pyramidal neuron size in Brodmann areas 44 and 45 in patients with autism}}. {Acta Neuropathol};2012 (Mar 31)
Autism is a neurodevelopmental disorder characterized by deficits in social interaction and social communication, as well as by the presence of repetitive and stereotyped behaviors and interests. Brodmann areas 44 and 45 in the inferior frontal cortex, which are involved in language processing, imitation function, and sociality processing networks, have been implicated in this complex disorder. Using a stereologic approach, this study aims to explore the presence of neuropathological differences in areas 44 and 45 in patients with autism compared to age- and hemisphere-matched controls. Based on previous evidence in the fusiform gyrus, we expected to find a decrease in the number and size of pyramidal neurons as well as an increase in volume of layers III, V, and VI in patients with autism. We observed significantly smaller pyramidal neurons in patients with autism compared to controls, although there was no difference in pyramidal neuron numbers or layer volumes. The reduced pyramidal neuron size suggests that a certain degree of dysfunction of areas 44 and 45 plays a role in the pathology of autism. Our results also support previous studies that have shown specific cellular neuropathology in autism with regionally specific reduction in neuron size, and provide further evidence for the possible involvement of the mirror neuron system, as well as impairment of neuronal networks relevant to communication and social behaviors, in this disorder.
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5. Johnson NL, Lashley J, Stonek AV, Bonjour A. {{Children With Developmental Disabilities at a Pediatric Hospital: Staff Education to Prevent and Manage Challenging Behaviors}}. {J Pediatr Nurs};2012 (Mar 27)
Children with developmental disabilities may get frustrated in unpredictable hospital environments. Frustration may escalate to challenging behaviors, which are a safety concern and may contribute to staff and patient injuries, use of restraints, and procedure delay or cancelations. The purpose of this article was to describe a pilot staff education program on preventing and managing challenging behaviors of children with developmental disabilities at a pediatric hospital. The 2-hour-long education (1 hour on-line and 1 hour instructor led) content focused on family-centered care and communication skills, including verbal judo modified for use in the health care setting. Participants in the instructor-led sessions reported improved knowledge and decreased fear about caring for children with developmental disabilities. Relationships of the education and fewer staff injuries, fewer canceled procedures, and decreased use of restraints merit further study.
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6. Moore GS, Kneitel AW, Walker CK, Gilbert WM, Xing G. {{Autism risk in small- and large-for-gestational-age infants}}. {Am J Obstet Gynecol};2012 (Apr);206(4):314 e311-319.
OBJECTIVE: We sought to determine whether small-for-gestational age (SGA) and large-for-gestational age (LGA) birthweights increase autism risk. STUDY DESIGN: This was a retrospective cohort analysis comparing children with autism (n = 20,206) within a birth cohort (n = 5,979,605). Stratification by sex and birthweight percentile (SGA, <5th or 5-10th percentile; appropriate size for gestational age [GA], >10th to <90th percentile; LGA, either 90-95th or >95th percentile) preceded Cochran-Mantel-Haenszel analysis for GA effect, and multivariate analysis. RESULTS: Autism risk was increased in preterm SGA (<5th percentile) infants 23-31 weeks (adjusted odds ratio [aOR], 1.60; 95% confidence interval [CI], 1.09-2.35) and 32-33 weeks (aOR, 1.83; 95% CI, 1.16-2.87), and term LGA (>95th percentile) infants 39-41 weeks (aOR, 1.16; 95% CI, 1.08-1.26), but was decreased in preterm LGA infants 23-31 weeks (aOR, 0.45; 95% CI, 0.21-0.95). CONCLUSION: SGA was associated with autism in preterm infants, while LGA demonstrated dichotomous risk by GA, with increased risk at term, and decreased risk in the premature infants. These findings likely reflect disparate pathophysiologies, and should influence prenatal counseling, pediatric autism screening, and further autism research.
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7. Ohta H, Yamada T, Watanabe H, Kanai C, Tanaka E, Ohno T, Takayama Y, Iwanami A, Kato N, Hashimoto RI. {{An fMRI study of reduced perceptual load-dependent modulation of task-irrelevant activity in adults with autism spectrum conditions}}. {Neuroimage};2012 (Mar 23)
Recent studies on selective attention have demonstrated that the perceptual load of a task determines the processing stage at which irrelevant sensory stimuli are filtered out. Although individuals with autism spectrum disorders conditions (ASC) have been repeatedly reported to display several kinds of abnormal behavior related to attention deficits, the neural mechanisms underlying these deficits have not been well investigated within the framework of the load dependency of selective attention. The present study used functional magnetic resonance imaging (fMRI) to examine the brain responses of adults with high-functioning ASC to irrelevant visual distractors while performing a visual target detection task under high or low perceptual load. We observed that the increased perceptual load activated regions of the fronto-parietal attention network of controls and ASC comparably. On the other hand, the visual cortex activity evoked by visual distractors was less modulated by the increased perceptual load in ASC than in controls. Simple regression analyses showed that the degree of the modulation was significantly correlated with the severity of the autistic symptoms. We also observed reduced load-dependent modulation of the functional connectivity between the intraparietal and visual regions in the ASC group. These results revealed neural correlates for abnormal perceptual load-dependent engagement of visual attention in ASC, which may underlie aspects of cognitive and behavioral characteristics of these disorders.
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8. Tassone F, Greco CM, Hunsaker MR, Seritan AL, Berman RF, Gane LW, Jacquemont S, Basuta K, Jin LW, Hagerman PJ, Hagerman RJ. {{Neuropathological, Clinical, and Molecular Pathology in Female Fragile X Premutation Carriers with and without FXTAS}}. {Genes Brain Behav};2012 (Mar 30)
Fragile X-associated tremor/ataxia syndrome (FXTAS) is an adult-onset neurodegenerative disorder associated with premutation alleles of the fragile X mental retardation 1 (FMR1) gene. Approximately 40% of older male premutation carriers, and a smaller proportion of females, are affected by FXTAS; due to the lower penetrance the characterization of the disorder in females is much less detailed. Core clinical features of FXTAS include intention tremor, cerebellar gait ataxia, and frequently parkinsonism, autonomic dysfunction, and cognitive deficits progressing to dementia in up to 50% of males. Here, we report the clinical, molecular, and neuropathological findings of eight female premutation carriers. Significantly, four of these women had dementia; of the four, three had FXTAS plus dementia. Post mortem examination revealed the presence of intranuclear inclusions in all eight cases, which included one asymptomatic premutation carrier who died from cancer. Among the four subjects with dementia, three had sufficient number of cortical amyloid plaques and neurofibrillary tangles to make Alzheimer’s disease a highly likely cause of dementia and a fourth case had dementia with cortical Lewy bodies. Dementia appears to be more common than originally reported in females with FXTAS. Although further studies are required, our observation suggests that in a portion of FXTAS cases and Alzheimer pathologies a synergistic effect on the progression of the disease may occurs.
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9. Taylor JL, Seltzer MM. {{Developing a Vocational Index for Adults with Autism Spectrum Disorders}}. {J Autism Dev Disord};2012 (Mar 31)
Existing methods of indexing the vocational activities of adults with autism spectrum disorders (ASD) have made significant contributions to research. Nonetheless, they are limited by problems with sensitivity and reliability. We developed an index of vocational and educational outcomes that captures the full range of activities experienced by adults with ASD, and that can be reliably coded across studies using specific decision rules. To develop this index, we used employment, vocational, and educational data collected from nearly 350 adults with ASD at 6 times over 12 years, as part of a larger longitudinal study. The resulting index consists of 11 categories coded on a 9-point scale, ranging from competitive employment and/or postsecondary educational program to no vocational/educational activities.
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10. Tetreault NA, Hakeem AY, Jiang S, Williams BA, Allman E, Wold BJ, Allman JM. {{Microglia in the Cerebral Cortex in Autism}}. {J Autism Dev Disord};2012 (Mar 31)
We immunocytochemically identified microglia in fronto-insular (FI) and visual cortex (VC) in autopsy brains of well-phenotyped subjects with autism and matched controls, and stereologically quantified the microglial densities. Densities were determined blind to phenotype using an optical fractionator probe. In FI, individuals with autism had significantly more microglia compared to controls (p = 0.02). One such subject had a microglial density in FI within the control range and was also an outlier behaviorally with respect to other subjects with autism. In VC, microglial densities were also significantly greater in individuals with autism versus controls (p = 0.0002). Since we observed increased densities of microglia in two functionally and anatomically disparate cortical areas, we suggest that these immune cells are probably denser throughout cerebral cortex in brains of people with autism.
