1. Bodner KE, Beversdorf DQ, Saklayen SS, Christ SE. {{Noradrenergic Moderation of Working Memory Impairments in Adults with Autism Spectrum Disorder}}. {J Int Neuropsychol Soc};2012 (Mar 14):1-9.
In addition to having difficulties with social communications, individuals with an autism spectrum disorder (ASD) often also experience impairment in higher-order, executive skills. The present study examined the effects of pharmacological modulation of the norepinephrine system on the severity of such impairments. A sample of 14 high-functioning adults with ASD and a demographically-matched comparison group of 13 typically developing individuals participated. An AX continuous performance test (AX-CPT) was used to evaluate working memory and inhibitory control. AX-CPT performance was assessed following administration of a single dose of propranolol (a beta adrenergic antagonist) and following placebo (sugar pill) administration. Individuals with ASD performed more poorly than non-ASD individuals in the working memory condition (BX trials). Importantly, administration of propranolol attenuated this impairment, with the ASD group performing significantly better in the propranolol condition than the placebo condition. Working memory performance of the non-ASD group was unaffected by propranolol/placebo administration. No group or medication effects were observed for the inhibition condition (AY trials). The present findings suggest that norepinephrine may play a role in some, but not necessarily all, cognitive impairments associated with ASD. Additional research is needed to fully understand whether this role is primarily causal or compensatory in nature. (JINS, 2012, 18, 1-9).
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2. Coo H, Ouellette-Kuntz H, Lam M, Yu CT, Dewey D, Bernier FP, Chudley AE, Hennessey PE, Breitenbach MM, Noonan AL, Lewis ME, Holden JJ. {{Correlates of age at diagnosis of autism spectrum disorders in six Canadian regions}}. {Chronic Dis Inj Can};2012 (Mar);32(2):90-100.
INTRODUCTION: Early identification of autism spectrum disorders (ASD) is important, since earlier exposure to behavioural intervention programs may result in better outcomes for the child. Moreover, it allows families timely access to other treatments and supports. METHODS: Using generalized linear modeling, we examined the association between child and family characteristics and the age at which 2180 children were diagnosed with ASD between 1997 and 2005 in six Canadian regions. RESULTS: A diagnosis of pervasive developmental disorder-not otherwise specified (PDD-NOS) or Asperger syndrome, rural residence, diagnosis in more recent years, and foreign birthplace were associated with a later age at diagnosis. Children who are visible minorities or who have siblings with ASD were more likely to be diagnosed earlier. Collectively, these factors explained little of the variation in age at diagnosis, however. CONCLUSION: While it is encouraging that ethnocultural identity, neighbourhood income, urban or rural residence, and sex of the child were not major contributors to disparities in the age when children were identified with ASD, more work is needed to determine what does account for the differences observed. Regional variations in the impact of several factors suggest that aggregating data may not be an optimal strategy if the findings are meant to inform policy and clinical practice at the local level.
3. Grillo E, Villard L, Clarke A, Ben Zeev B, Pineda M, Bahi-Buisson N, Hryniewiecka-Jaworska A, Bienvenu T, Armstrong J, Martinez AR, Mari F, Veneselli E, Russo S, Vignoli A, Pini G, Djuric M, Bisgaard AM, Mejaski-Bosnjak V, Polgar N, Cogliati F, Ravn K, Pintaudi M, Melegh B, Craiu D, Djukic A, Renieri A. {{Rett Networked Database: An integrated clinical and genetic network of Rett syndrome databases}}. {Hum Mutat};2012 (Mar 13)
Rett syndrome (RTT) is a neurodevelopmental disorder with one principal phenotype and several distinct, atypical variants (Zappella, early seizure onset and congenital variants). Mutations in MECP2 are found in most cases of classic RTT but at least two additional genes, CDKL5 and FOXG1, can underlie some (usually variant) cases. There is only limited correlation between genotype and phenotype. The Rett Networked Database (http://www.rettdatabasenetwork.org/) has been established to share clinical an genetic information. Through an ‘adaptor’ process of data harmonization, a set of 293 clinical items and 16 genetic items was generated; 62 clinical and 7 genetic items constitute the core dataset; 23 clinical items contain longitudinal information. The database contains information on 1838 patients from eleven countries (December 2011), with or without mutations in known genes. These numbers can expand indefinitely. Data are entered by a clinician in each center who supervises accuracy. This network was constructed to make available pooled international data for the study of RTT natural history and genotype-phenotype correlation and to indicate the proportion of patients with specific clinical features and mutations. We expect that the network will serve for the recruitment of patients into clinical trials and for developing quality measures to drive up standards of medical management.
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4. Ouellette-Kuntz H, Coo H, Yu CT, Lewis ME, Dewey D, Hennessey PE, Jackman PD, Breitenbach MM, Holden JJ. {{Status Report – National Epidemiologic Database for the Study of Autism in Canada (NEDSAC)}}. {Chronic Dis Inj Can};2012 (Mar);32(2):84-89.
In 2001, the Autism Spectrum Disorders-Canadian-American Research Consortium (ASD-CARC) launched a program of research on autism spectrum disorders (ASD). As part of that undertaking, and in response to concerns about the growing proportion of children diagnosed with ASD, the National Epidemiologic Database for the Study of Autism in Canada (NEDSAC; www.nedsac.ca) was created as a multi-site ASD surveillance program. Government departments, clinicians and researchers collaborated to establish regional teams to collect information on children with ASD in British Columbia, Calgary (Alberta), Manitoba, southeastern Ontario, Prince Edward Island, and Newfoundland and Labrador. NEDSAC provides estimates of the prevalence of ASD in Canadian children and a profile of those who are affected, and allows researchers to monitor trends in age at diagnosis. These data can help the health, education and social services sectors with planning and allocation of resources.
5. Sivaratnam CS, Cornish K, Gray KM, Howlin P, Rinehart NJ. {{Brief Report: Assessment of the Social-Emotional Profile in Children with Autism Spectrum Disorders using a Novel Comic Strip Task}}. {J Autism Dev Disord};2012 (Mar 15)
This study investigated whether the novel Comic Strip Task (CST) could be used to detect Theory-of-Mind impairments (ToM) in 4- to 8-year-old children with high functioning Autism Spectrum Disorders (ASD). Twelve children with either high-functioning autism or Asperger’s Disorder and 12 typically-developing children completed the 21-item measure. The overall CST demonstrated moderate internal consistency but the Belief-understanding subscale was excluded from the test due to poor reliability. As predicted, the ASD group performed significantly more poorly than controls on the overall 2-subscale CST and on the intention-understanding subscale. No group differences were found in emotion-understanding subscale performance. Controlling for age, verbal ability was positively correlated with overall CST performance across groups. CST performance in the ASD group positively correlated with parent-reports of communication difficulties. Despite some limitations with the belief-understanding subscale, the CST has promising psychometric features warranting further development of this measure.
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6. Vande Wydeven K, Kwan A, Hardan AY, Bernstein JA. {{Underutilization of Genetics Services for Autism: The Importance of Parental Awareness and Provider Recommendation}}. {J Genet Couns};2012 (Mar 14)
Reasons for the underutilization of genetics services by families of children with autism spectrum disorders (ASD) are not well understood. We report the identification of factors associated with this underuse. Survey-based study of parents and/or guardians of children with ASD. One hundred fifty-five families completed the questionnaire. Thirty-one of 155 (20%) children had seen a genetics professional. Forty-nine of 154 (32%) children had undergone genetic testing. Parents whose child saw a genetics professional were more likely to 1) Have a primary provider refer for or suggest a genetics evaluation 2) Have asked for a referral, and/or 3) Know another person with a genetic cause of ASD. amilies of children with ASD who have not received genetics services are less aware of their availability and utility. They are also less likely to have their provider recommend a clinical genetics evaluation. Efforts should be taken to increase awareness of both health providers and parents regarding the usefulness of genetics services for ASD.
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7. Wilson LB, Tregellas JR, Slason E, Pasko BE, Hepburn S, Rojas DC. {{Phonological processing in first-degree relatives of individuals with autism: An fMRI study}}. {Hum Brain Mapp};2012 (Mar 15)
Autism spectrum disorders (ASD) are complex neurodevelopmental disorders. Twin studies have provided heritability estimates as high as 90% for idiopathic ASD. Further evidence for the spectrum’s heritability is provided by the presence of the broad autism phenotype (BAP) in unaffected first-degree relatives. Language ability, specifically phonological processing, is proposed to be a core BAP trait. To date, however, no functional neuroimaging investigations of phonological processing in relatives of individuals with ASD have been undertaken. We conducted a functional magnetic resonance imaging (fMRI) study in parents of children with ASD utilizing a priming task probing implicit phonological processing. In our condition that placed heavier demands on phonological recoding, parents exhibited greater hemodynamic responses than controls in a network of cortical regions involved in phonological processing. Across conditions, parents exhibited enhanced priming-induced response suppression suggesting compensatory neural processing. A nonword repetition test used in previous studies of relatives was also administered. Correlations between this measure and our functional measures also suggested compensatory processing in parents. Regions exhibiting atypical responses in parents included regions previously implicated in the spectrum’s language impairments and found to exhibit structural abnormalities in a parent study. These results suggest a possible neurobiological substrate of the phonological deficits proposed to be a core BAP trait. However, these results should be considered preliminary. No previous fMRI study has investigated phonological processing in ASD, so replication is required. Furthermore, interpretation of our fMRI results is limited by the fact that the parent group failed to exhibit behavioral evidence of phonological impairments. Hum Brain Mapp, 2012. (c) 2012 Wiley Periodicals, Inc.
