1. Apicella F, Chericoni N, Costanzo V, Baldini S, Billeci L, Cohen D, Muratori F. {{Reciprocity in interaction: a window on the first year of life in autism}}. {Autism research and treatment}. 2013;2013:705895.
From early infancy onwards, young children appear motivated to engage reciprocally with others and share psychological states during dyadic interactions. Although poor reciprocity is one of the defining features of autism spectrum disorders (ASDs), few studies have focused on the direct assessment of real-life reciprocal behavior; consequently, our knowledge of the nature and the development of this core feature of autism is still limited. In this study, we describe the phenomenon of reciprocity in infant-caregiver interaction by analyzing family movies taken during the first year of life of 10 infants with ASD and 9 infants with typical development (TD). We analyzed reciprocal behaviors by means of a coding scheme developed for this purpose (caregiver-infant reciprocity scale (CIRS)). Infants with ASD displayed less motor activity during the first semester and subsequently fewer vocalizations, compared to TD infants. Caregivers of ASD infants showed in the second semester shorter periods of involvement and a reduction of affectionate touch. These results suggest that from the first months of life a nonsynchronic motor-vocal pattern may interfere in different ways with the development of reciprocity in the primary relationship between infants later diagnosed with ASD and their caregivers.
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2. Betancur C, Buxbaum JD. {{SHANK3 haploinsufficiency: a « common » but underdiagnosed highly penetrant monogenic cause of autism spectrum disorders}}. {Molecular autism}. 2013 Jun 11;4(1):17.
Autism spectrum disorders (ASD) are etiologically heterogeneous, with hundreds of rare, highly penetrant mutations and genomic imbalances involved, each contributing to a very small fraction of cases. As reviewed here, Phelan-McDermid syndrome, caused by deletion of 22q13.33 or SHANK3 mutations, is one of the more prevalent monogenic causes of ASD, explaining at least 0.5% of cases. In this issue of Molecular Autism, Soorya and colleagues evaluated 32 patients with SHANK3 haploinsufficiency using gold-standard diagnostic assessments and showed that 84% met criteria for ASD, including 75% meeting criteria for autism. This study and prior studies demonstrate that this syndrome is also one of the more penetrant causes of ASD. We note that SHANK3 haploinsufficiency remains underdiagnosed, although with the increasingly widespread use of chromosomal microarray analysis and targeted sequencing of SHANK3, the number of cases is bound to rise.
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3. Broadbent J, Galic I, Stokes MA. {{Validation of autism spectrum quotient adult version in an Australian sample}}. {Autism research and treatment}. 2013;2013:984205.
The Autism Spectrum Quotient is used to assess autistic spectrum traits in intellectually competent adults in both the general population and the autism spectrum community. While the autism spectrum Quotient has been validated in several different cultures, to date no study has assessed the psychometrics of the Autism Spectrum Quotient on an Australian population. The purpose of this study was to assess the psychometrics of the autism spectrum Quotient in an Australian sample of both typically developing individuals (n = 128) and individuals with autism spectrum disorder (n = 104). The results revealed that the internal consistency and the test-retest reliability were satisfactory; individuals with autism spectrum disorder scored higher on total Autism Spectrum Quotient score and its subscales than typically developing individuals; however, gender differences were not apparent on total score. Possible cultural differences may explain some of the psychometric variations found. The results of this analysis revealed that the Autism Spectrum Quotient was a reliable instrument for investigating variation in autistic symptomology in both typically developing and Autism Spectrum Disorders populations within an Australian population.
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4. Cook J, Swapp D, Pan X, Bianchi-Berthouze N, Blakemore SJ. {{Atypical interference effect of action observation in autism spectrum conditions}}. {Psychological medicine}. 2013 Jun 13:1-10.
BACKGROUND: Observing incongruent actions interferes with ongoing action execution. This ‘interference effect’ is larger for observed biological actions than for non-biological actions. The current study used virtual reality to investigate the biological specificity of interference effects of action observation in autism spectrum conditions (ASC). Method High-functioning adults with ASC and age- and IQ-matched healthy controls performed horizontal sinusoidal arm movements whilst observing arm movements conducted by a virtual reality agent with either human or robot form, which moved with either biological motion or at a constant velocity. In another condition, participants made the same arm movements while observing a real human. Observed arm movements were either congruent or incongruent with executed arm movements. An interference effect was calculated as the average variance in the incongruent action dimension during observation of incongruent compared with congruent movements. RESULTS: Control participants exhibited an interference effect when observing real human and virtual human agent incongruent movements but not when observing virtual robot agent movements. Individuals with ASC differed from controls in that they showed no interference effects for real human, virtual human or virtual robot movements. CONCLUSIONS: The current study demonstrates atypical interference effects in ASC.
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5. Ijichi S, Ijichi N, Ijichi Y, Hirotaki K, Sameshima H, Kawaike Y, Morioka H. {{Quantitative Nature of Social Vulnerability and Autism: An Important Paradigm Shift in the DSM-5 for Autism Spectrum Disorder}}. {ISRN neurology}. 2013;2013:201719.
In the Diagnostic and Statistical Manual of Mental Disorders, 4th edition (DSM-IV), autistic characteristics in social interaction and communication are described as qualitative impairments. However, the difference between autistics and nonautistics in the draft of the 5th edition (DSM-5 draft) is quantitative rather than qualitative. The word « qualitative » is deleted in the draft text, and it is specified that the relation between social demands and individual limited capacities is critical for symptom manifestation (criterion C). Because the proposed levels of support requirement in the draft are mere observable outcomes of social vulnerability, the boundary between level 1 and nonautistic condition is determined by the relation between social demands and individual capacities. In addition to the introduction of the single category (autism spectrum disorder (ASD)) to cover the entire case spectrum, the DSM-5 draft is clearly based on a conviction that ASD is indistinguishable from the normal behavioral range. This concise review provides an explanation for this implicit paradigm shift from qualitative to quantitative. Importantly, the conditional role of social demands for symptom manifestation in the draft can be plausibly interpreted using a unique liability-probability model.
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6. Kim JE, Shin MS, Seo TB, Ji ES, Baek SS, Lee SJ, Park JK, Kim CJ. {{Treadmill exercise ameliorates motor disturbance through inhibition of apoptosis in the cerebellum of valproic acid-induced autistic rat pups}}. {Molecular medicine reports}. 2013 Jun 12.
Autism is a neurological disorder that occurs during childhood and is characterized by impairments in social interaction and communication, as well as restricted and repetitive behaviors. Abnormalities of the cerebellum in autism include Purkinje cell loss and motor disturbance. In the present study, we evaluated the effect of treadmill exercise on motor coordination and balance in correlation with reelin expression and the rate of apoptosis in the cerebellum of autistic rat pups. For the induction of the autism-like animal models, 400 mg/kg valproic acid was subcutaneously injected into rat pups on postnatal day 14. Rat pups in the exercise groups were forced to run on a treadmill for 30 min, once a day, five times a week for 4 weeks, starting on postnatal day 28. Motor coordination and balance, as measured using the rotarod test and vertical pole test, were affected by the induction of autism. By contrast, treadmill exercise ameliorated motor dysfunction in the autistic rat pups. The expression levels of reelin, GAD67 and cyclin D1 in the cerebellum of the autistic rat pups were decreased, while the expression levels of these molecules were increased in autistic rat pups who engaged in treadmill exercise. In the cerebellum of the autistic rat pups, Bcl-2 expression was decreased and Bax expression was increased. By contrast, treadmill exercise enhanced Bcl-2 expression and suppressed Bax expression. The therapeutic effect of treadmill exercise on motor deficits may be due to the reelin-mediated anti-apoptotic effect on cerebellar Purkinje neurons.
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7. Pastore LM, Karns LB, Ventura K, Clark ML, Steeves RH, Callanan N. {{Longitudinal Interviews of Couples Diagnosed with Diminished Ovarian Reserve Undergoing Fragile X Premutation Testing}}. {Journal of genetic counseling}. 2013 Jun 14.
About 10 % of infertile/subfertile women are diagnosed with diminished ovarian reserve (DOR), of which < 5 % will become pregnant spontaneously. Fragile X (FMR1) genetic testing may provide a reason for her early ovarian aging and/or have reproductive implications. Seven women with DOR (genetic study subset) and the male partners of six of these women were separately interviewed about the experience of being asked to undergo this unanticipated genetic test. Three interviews were conducted (before, within 1 week after, and 3 months after learning the test results). None of the participants carried the FMR1 premutation (largest FMR1 allele 27-50 CGG repeats). For women, their pregnancy-seeking journey was long and exhausting. Women understood the reproductive implications of carrying the FMR1 premutation, and hoped for a negative result. Being offered a genetic test caused women to pause and re-think their future reproductive plans. Husbands viewed the infertility journey as filled with unknowns, of which the genetic test results would be one more puzzle piece. The expense of fertility testing/treatment was mentioned by both spouses, though more notably by husbands. The introduction of a possible genetic cause of infertility, with additional potential health consequences for future biological children, caused women to re-think their quest for pregnancy. In contrast, the genetic test was viewed as an additional source of information for their husbands as opposed to raising concern regarding potential reproductive ramifications.
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8. Pizzarelli R, Cherubini E. {{Developmental regulation of GABAergic signalling in the hippocampus of neuroligin 3 R451C knock-in mice: an animal model of Autism}}. {Frontiers in cellular neuroscience}. 2013;7:85.
Autism Spectrum Disorders (ASDs) comprise an heterogeneous group of neuro-developmental abnormalities, mainly of genetic origin, characterized by impaired social interactions, communications deficits, and stereotyped behaviors. In a small percentage of cases, ASDs have been found to be associated with single mutations in genes involved in synaptic function. One of these involves the postsynaptic cell adhesion molecule neuroligin (NL) 3. NLs interact with presynaptic neurexins (Nrxs) to ensure a correct cross talk between post and presynaptic specializations. Here, transgenic mice carrying the human R451C mutation of Nlgn3, were used to study GABAergic signaling in the hippocampus early in postnatal life. Whole cell recordings from CA3 pyramidal neurons in slices from NL3(R451C) knock-in mice revealed an enhanced frequency of Giant Depolarizing Potentials (GDPs), as compared to controls. This effect was probably dependent on an increased GABAergic drive to principal cells as demonstrated by the enhanced frequency of miniature GABAA-mediated (GPSCs), but not AMPA-mediated postsynaptic currents (EPSCs). Changes in frequency of mGPSCs were associated with an acceleration of their decay kinetics, in the absence of any change in unitary synaptic conductance or in the number of GABAA receptor channels, as assessed by peak scaled non-stationary fluctuation analysis. The enhanced GABAergic but not glutamatergic transmission early in postnatal life may change the excitatory/inhibitory balance known to play a key role in the construction and refinement of neuronal circuits during postnatal development. This may lead to behavioral deficits reminiscent of those observed in ASDs patients.
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9. Soorya L, Kolevzon A, Zweifach J, Lim T, Dobry Y, Schwartz L, Frank Y, Wang AT, Cai G, Parkhomenko E, Halpern D, Grodberg D, Angarita B, Willner JP, Yang A, Canitano R, Chaplin W, Betancur C, Buxbaum JD. {{Prospective investigation of autism and genotype-phenotype correlations in 22q13 deletion syndrome and SHANK3 deficiency}}. {Molecular autism}. 2013 Jun 11;4(1):18.
BACKGROUND: 22q13 deletion syndrome, also known as Phelan-McDermid syndrome, is a neurodevelopmental disorder characterized by intellectual disability, hypotonia, delayed or absent speech, and autistic features. SHANK3 has been identified as the critical gene in the neurological and behavioral aspects of this syndrome. The phenotype of SHANK3 deficiency has been described primarily from case studies, with limited evaluation of behavioral and cognitive deficits. The present study used a prospective design and inter-disciplinary clinical evaluations to assess patients with SHANK3 deficiency, with the goal to provide a comprehensive picture of the medical and behavioral profile of the syndrome. METHODS: A serially ascertained sample of patients with SHANK3 deficiency (n = 32) was evaluated by a team of child psychiatrists, neurologists, clinical geneticists, molecular geneticists and psychologists. Patients were evaluated for autism spectrum disorder using the Autism Diagnostic Interview-Revised and the Autism Diagnostic Observation Schedule-G. RESULTS: Thirty participants with 22q13.3 deletions ranging in size from 101 kb to 8.45 Mb and two participants with de novo SHANK3 mutations were included. The sample was characterized by high rates of autism spectrum disorder: 27 (84%) met criteria for autism spectrum disorder and 24 (75%) for autistic disorder. Most patients (77%) exhibited severe to profound intellectual disability and only five (19%) used some words spontaneously to communicate. Dysmorphic features, hypotonia, gait disturbance, recurring upper respiratory tract infections, gastroesophageal reflux and seizures were also common. Analysis of genotype-phenotype correlations indicated that larger deletions were associated with increased levels of dysmorphic features, medical comorbidities and social communication impairments related to autism. Analyses of individuals with small deletions or point mutations identified features related to SHANK3 haploinsufficiency, including ASD, seizures and abnormal EEG, hypotonia, sleep disturbances, abnormal brain MRI, gastroesophageal reflux, and certain dysmorphic features. CONCLUSIONS: This study supports findings from previous research on the severity of intellectual, motor, and speech impairments seen in SHANK3 deficiency, and highlights the predominance of autism spectrum disorder in the syndrome. Limitations of existing evaluation tools are discussed, along with the need for natural history studies to inform clinical monitoring and treatment development in SHANK3 deficiency.
