1. Albrecht MA, Stuart GW, Falkmer M, Ordqvist A, Leung D, Foster JK, Falkmer T. {{Brief Report: Visual Acuity in Children with Autism Spectrum Disorders}}. {J Autism Dev Disord}. 2014.
Recently, there has been heightened interest in suggestions of enhanced visual acuity in autism spectrum disorders (ASD) which was sparked by evidence that was later accepted to be methodologically flawed. However, a recent study that claimed children with ASD have enhanced visual acuity (Brosnan et al. in J Autism Dev Disord 42:2491-2497, 2012) repeated a critical methodological flaw by using an inappropriate viewing distance for a computerised acuity test, placing the findings in doubt. We examined visual acuity in 31 children with ASD and 33 controls using the 2 m 2000 Series Revised Early Treatment Diabetic Retinopathy Study chart placed at twice the conventional distance to better evaluate possible enhanced acuity. Children with ASD did not demonstrate superior acuity. The current findings strengthen the argument that reports of enhanced acuity in ASD are due to methodological flaws and challenges the reported association between visual acuity and systemising type behaviours.
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2. Bouvet L, Simard-Meilleur AA, Paignon A, Mottron L, Donnadieu S. {{Auditory local bias and reduced global interference in autism}}. {Cognition}. 2014; 131(3): 367-72.
Processing local elements of hierarchical patterns at a superior level and independently from an intact global influence is a well-established characteristic of autistic visual perception. However, whether this confirmed finding has an equivalent in the auditory modality is still unknown. To fill this gap, 18 autistics and 18 typical participants completed a melodic decision task where global and local level information can be congruent or incongruent. While focusing either on the global (melody) or local level (group of notes) of hierarchical auditory stimuli, participants have to decide whether the focused level is rising or falling. Autistics showed intact global processing, a superior performance when processing local elements and a reduced global-to-local interference compared to typical participants. These results are the first to demonstrate that autistic processing of auditory hierarchical stimuli closely parallels processing of visual hierarchical stimuli. When analyzing complex auditory information, autistic participants present a local bias and a more autonomous local processing, but not to the detriment of global processing.
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3. Burke MM, Hodapp RM. {{Relating stress of mothers of children with developmental disabilities to family-school partnerships}}. {Intellect Dev Disabil}. 2014; 52(1): 13-23.
Abstract Although mothers of children with intellectual and developmental disabilities (IDD) experience high levels of stress and schools constitute an important resource, the relation remains unknown between maternal stress and educational services. Responding to a national, web-based survey, 965 mothers of students with disabilities completed a 163-item questionnaire about parent stress. We examined which child, parent, and parent-school characteristics correlated with maternal stress. Mothers with lower stress levels reported better parent-school relationships and low levels of parent advocacy. However, lower stress levels were predominantly shown by mothers with good-to-excellent parent-school relationships (vs. poor-to-fair partnerships) and who engaged in virtually no (vs. any) advocacy activities. Lower maternal stress levels were also noted when children had fewer behavior problems, Down syndrome, and did not have autism. Less stress was also reported by mothers who had not enacted procedural safeguards, were minorities, and rated themselves lower on neuroticism and were more extroverted, dependable, and open to new experiences. This study has important implications for practitioners and researchers.
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4. Cederlund M, Miniscalco C, Gillberg C. {{Pre-schoolchildren with autism spectrum disorders are rarely macrocephalic: A population study}}. {Res Dev Disabil}. 2014.
Numerous clinical studies over the past decades have concluded that there is an association between autism spectrum disorders (ASD) and large head size. Lately, some studies have reported conflicting results. The present study was conducted with a view to assess the presence of macrocephaly in a community-representative group of pre-school children with ASD. The prevalence of ASD in this general population was 0.8%. Thirty-three children (5 girls, 28 boys) recruited after general population screening for ASD, and diagnosed with ASD (two-thirds not globally delayed) were assessed as regards growth parameters; height, weight, and head circumference (HC), at birth and at comprehensive medical-psychiatric diagnostic examinations at a mean age of 3 years. Macrocephaly in the present study was defined as HC above the 97th percentile, and >/=2 SD above recorded length/height. Only one of the 33 children (3%) had macrocephaly which is similar to the general population prevalence. Another 9% had a big but proportional head. None of the children were microcephalic. In this community-based study we found no evidence to support a strong link between a large head size and ASD. Conclusions must be guarded because of the relatively small number of ASD cases included.
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5. Ceroni F, Sagar A, Simpson NH, Gawthrope AJ, Newbury DF, Pinto D, Francis SM, Tessman DC, Cook EH, Monaco AP, Maestrini E, Pagnamenta AT, Jacob S. {{A Deletion Involving CD38 and BST1 Results in a Fusion Transcript in a Patient With Autism and Asthma}}. {Autism Res}. 2014.
CD38 encodes a ligand in the oxytocin signaling pathway. Some single nucleotide polymorphisms in this gene have been associated with low serum oxytocin levels in autism spectrum disorder (ASD) patients. Oxytocin disruption has been hypothesized to account for features of ASD, including impaired communication and social behavior, based on animal studies. Recent human studies have shown administration of oxytocin improving emotion recognition, promoting social behavior, and improving auditory processing of social stimuli in ASD patients. In addition to its role in oxytocin signaling, CD38 is involved in the regulation of calcium concentration in airway smooth muscle with impairment of CD38 being implicated in airway diseases like asthma. While a number of studies have implicated rare chromosomal deletions and duplications in helping determine genetic risk for autism, there are to our knowledge no reports describing rearrangements involving CD38 or deletions in patients with ASD. Here, we present two sisters diagnosed with autism and with features of regression-previously acquired speech lost in the second year of life. The younger sister, who also had asthma, inherited a maternal deletion of 4p15.32 that results in a BST1-CD38 fusion transcript. Their mother’s deletion was mosaic and she was not affected. Although further work is required to assess functional consequences of the fusion transcript, we hypothesize that the proband’s deletion may have served as a risk factor for autism that, when combined with other susceptibility variants, resulted in a more severe presentation than her sister. Autism Res 2014, : -. (c) 2014 International Society for Autism Research, Wiley Periodicals, Inc.
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6. Chaudhary AG, Hussein IR, Abuzenadah A, Gari M, Bassiouni R, Sogaty S, Lary S, Al-Quaiti M, Al Balwi M, Al Qahtani M. {{Molecular diagnosis of fragile x syndrome using methylation sensitive techniques in a cohort of patients with intellectual disability}}. {Pediatr Neurol}. 2014; 50(4): 368-76.
BACKGROUND: Fragile X syndrome, the most common form of inherited intellectual disability, is caused by expansion of CGG trinucleotide repeat at the 5′ untranslated region of the FMR1 gene at Xq27. In affected individuals, the CGG repeat expansion leads to hypermethylation and the gene is transcriptionally inactive. Our aim was to identify fragile X syndrome among children with intellectual disability in Saudi Arabia. PATIENTS AND METHODS: The study included 63 patients (53 males, 10 females) presented with intellectual disability, 29 normal subjects, and 23 other family members. DNA samples from six patients previously diagnosed with fragile X syndrome by Southern blot technique were used as positive controls. The method was based on bisulfite treatment of DNA followed by two different techniques. The first technique applied polymerase chain reaction amplification using one set of primers specific for amplifying methylated CpG dinucleotide region; another set designed to amplify the unmethylated CGG repeats. The second technique used the methylation-specific melting curve analysis for detection of methylation status of the FMR1 promoter region. RESULTS: Molecular testing using methylation sensitive polymerase chain reaction had shown amplified products in all normal subjects using unmethylated but not methylated primers indicating normal alleles, whereas amplified products were obtained using methylated polymerase chain reaction primers in fragile X syndrome-positive samples and in 9 of 53 males, indicating affected individuals. Molecular testing using melting curve analysis has shown a single low melting peak in all normal males and in (44/53) patients indicating unmethylated FMR1 gene, whereas high melting peak indicating methylated gene was observed in the fragile X syndrome-positive samples and in 9 of 53 patients. We found 100% concordance between results of both techniques and the results of Southern blot analysis. Three samples have shown both methylated and unmethylated alleles, indicating possible mosaicism. No female patients or carriers could be detected by both techniques. CONCLUSION: The technique can be applied for the rapid screening for fragile X syndrome among patients with intellectual disability. The impact of mosaicism on clinical severity needs further investigation.
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7. Chomiak T, Hung J, Cihal A, Dhaliwal J, Baghdadwala M, Dzwonek A, Podgorny P, Hu B. {{Auditory-cued sensorimotor task reveals disengagement deficits in rats exposed to the autism-associated teratogen valproic acid}}. {Neuroscience}. 2014.
Autism Spectrum Disorder (ASD) is often found to co-exist with non-core behavioral manifestations that include difficulties in disengagement of attention to sensory cues. Here we examined whether this behavioral abnormality can be induced in rats prenatally exposed to valproic acid (VPA), a well-established teratogen associated with ASD animal models. We tested rats using an auditory-cued sensorimotor task (ACST) based on the premise that ACST will be more sensitive to developmental changes in temporal association cortex (TeA) of the posterior attention system. We show that VPA rats learned the ACST markedly faster than control animals, but they exhibited a profound preoccupation with cues associated with the expectancy at the reward location such that disengagement was disrupted. Control rats on the other hand were able to disengage and utilize auditory cues for re-engagement. However, both control and VPA-treated rats performed similarly when tested on novel object recognition (NOR) and novel context mismatch (NOCM) behavioral tasks that are known to be sensitive to normal perirhinal and prefrontal network functioning respectively. Consistent with disrupted posterior rather than frontal networks, we also report that VPA can selectively act on deep-layer TeA cortical neurons by showing that VPA promotes increased dendritic density in isolated deep-layer TeA but not frontal neurons. These results provide a useful approach to examine the role of cue-dependent control of attention systems in rodent models of autism and suggest that disengagement impairments may arise from an inability to flexibly modify behavior through the appropriate use of sensory cue associations.
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8. Cleary L, Brady N, Fitzgerald M, Gallagher L. {{Holistic processing of faces as measured by the Thatcher illusion is intact in autism spectrum disorders}}. {Autism}. 2014.
Impaired face perception in autism spectrum disorders is thought to reflect a perceptual style characterized by componential rather than configural processing of faces. This study investigated face processing in adolescents with autism spectrum disorders using the Thatcher illusion, a perceptual phenomenon exhibiting ‘inversion effects’ that characterize typical face processing. While previous studies used a limited range of face orientations, we measured perception of normality/grotesqueness of faces at seven orientations ranging from upright to inverted to allow for a detailed comparison of both reaction time and error by orientation profiles. We found that, like their typically developing peers, adolescents with autism spectrum disorders show strong inversion effects whereby reaction times were longer and error rates greater at inverted when compared to upright orientations. Additionally, the adolescents with autism spectrum disorders, like their peers in the typically developing group, show a marked nonlinearity in the error by orientation profile. Error is roughly constant out to 90 degrees and then increases steeply, indicating a sudden shift from configural to local processing that reflects experience with faces in their typical orientations. These findings agree with recent reports that face perception is qualitatively similar in autistic and neurotypical groups.
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9. Dejong H, Bunton P, Hare DJ. {{A Systematic Review of Interventions Used to Treat Catatonic Symptoms in People with Autistic Spectrum Disorders}}. {J Autism Dev Disord}. 2014.
A systematic review was conducted to examine the efficacy of a range of treatments for autistic catatonia. The review identified 22 relevant papers, reporting a total of 28 cases including both adult and paediatric patients. Treatment methods included electroconvulsive therapy (ECT), medication, behavioural and sensory interventions. Quality assessment found the standard of the existing literature to be generally poor, with particular limitations in treatment description and outcome measurement. There is some limited evidence to support the use of ECT, high dose lorazepam and behavioural interventions for people with autistic catatonia. However, there is a need for controlled, high-quality trials. Reporting of side effects and adverse events should also be improved, in order to better evaluate the safety of these treatments.
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10. Dvash J, Ben-Zeev A, Noga A, Shamay-Tsoory S. {{The road not taken: Social vs. private comparisons in Aspergers syndrome and high functioning autism}}. {Psychiatry Res}. 2014.
Evaluation of the outcomes of our decisions may instigate comparisons of our actual outcome with those of others (social comparisons) or comparisons with alternative outcomes of choices not made (private comparisons). Previous research has suggested a deficit in attention to social information among individuals with autism spectrum disorders. As social comparison involves the processing of social information, here we investigated the orientation towards and sensitivity to social vs. private comparisons in individuals with autism spectrum disorders. We compared the sensitivity to social vs. private comparisons among individuals diagnosed with Aspergers syndrome or High Functioning Autism, using a task that entailed monetary rewards. Results showed that while individuals with AS generally demonstrate comparable sensitivity to absolute and relative rewards, they show less sensitivity to social comparison as compared to controls. Furthermore, they are characterized by a higher sensitivity to private rather than social comparison. These results suggest that low sensitivity to social comparisons is an important factor to consider in autism spectrum disorders.
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11. Egger G, Roetzer KM, Noor A, Lionel AC, Mahmood H, Schwarzbraun T, Boright O, Mikhailov A, Marshall CR, Windpassinger C, Petek E, Scherer SW, Kaschnitz W, Vincent JB. {{Identification of risk genes for autism spectrum disorder through copy number variation analysis in Austrian families}}. {Neurogenetics}. 2014.
Autism or autism spectrum disorder (ASD) is a range of neurodevelopmental disorders starting in early childhood and is characterized by impairments in communication and reciprocal social interaction and presence of restricted and repetitive patterns of behavior. The contribution of genetic factors to autism is clear in twin and family studies. It is apparent that, overall, ASD is a complex non-Mendelian disorder. Recent studies suggest that copy number variations (CNVs) play a significant role in the etiology of ASD. For the current work, we recruited 245 family members from 73 ASD families from Styria, Austria. The DNA from probands was genotyped with Affymetrix single nucleotide polymorphism (SNP) 6.0 microarrays to screen for CNVs in their genomes. Analysis of the microarray data was performed using three different algorithms, and a list of stringent calls was compared to existing CNV data from over 2,357 controls of European ancestry. For stringent calls not present in controls, quantitative real-time PCR (qRT-PCR) was used to validate the CNVs in the probands and in their family members. Twenty-two CNVs were validated from this set (five of which are apparently de novo), many of which appear likely to disrupt genes that may be considered as good candidates for neuropsychiatric disorders, including DLG2, S100B, ARX, DIP2A, HPCAL1, and GPHN. Several others disrupt genes that have previously been implicated in autism, such as BDNF, AUTS2, DPP6, and C18orf22, and our data add to the growing evidence of their involvement in ASD.
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12. Engineer CT, Centanni TM, Im KW, Borland MS, Moreno NA, Carraway RS, Wilson LG, Kilgard MP. {{Degraded auditory processing in a rat model of autism limits the speech representation in non-primary auditory cortex}}. {Dev Neurobiol}. 2014.
Although individuals with autism are known to have significant communication problems, the cellular mechanisms responsible for impaired communication are poorly understood. Valproic acid (VPA) is an anticonvulsant that is a known risk factor for autism in prenatally exposed children. Prenatal VPA exposure in rats causes numerous neural and behavioral abnormalities that mimic autism. We predicted that VPA exposure may lead to auditory processing impairments which may contribute to the deficits in communication observed in individuals with autism. In this study, we document auditory cortex responses in rats prenatally exposed to VPA. We recorded local field potentials and multiunit responses to speech sounds in primary auditory cortex, anterior auditory field, ventral auditory field and posterior auditory field in VPA exposed and control rats. Prenatal VPA exposure severely degrades the precise spatiotemporal patterns evoked by speech sounds in secondary, but not primary auditory cortex. This result parallels findings in humans and suggests that secondary auditory fields may be more sensitive to environmental disturbances and may provide insight into possible mechanisms related to auditory deficits in individuals with autism. (c) 2014 Wiley Periodicals, Inc. Develop Neurobiol, 2014.
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13. Fink E, de Rosnay M, Wierda M, Koot HM, Begeer S. {{Brief Report: Accuracy and Response Time for the Recognition of Facial Emotions in a Large Sample of Children with Autism Spectrum Disorders}}. {J Autism Dev Disord}. 2014.
The empirical literature has presented inconsistent evidence for deficits in the recognition of basic emotion expressions in children with autism spectrum disorders (ASD), which may be due to the focus on research with relatively small sample sizes. Additionally, it is proposed that although children with ASD may correctly identify emotion expression they rely on more deliberate, more time-consuming strategies in order to accurately recognize emotion expressions when compared to typically developing children. In the current study, we examine both emotion recognition accuracy and response time in a large sample of children, and explore the moderating influence of verbal ability on these findings. The sample consisted of 86 children with ASD (M age = 10.65) and 114 typically developing children (M age = 10.32) between 7 and 13 years of age. All children completed a pre-test (emotion word-word matching), and test phase consisting of basic emotion recognition, whereby they were required to match a target emotion expression to the correct emotion word; accuracy and response time were recorded. Verbal IQ was controlled for in the analyses. We found no evidence of a systematic deficit in emotion recognition accuracy or response time for children with ASD, controlling for verbal ability. However, when controlling for children’s accuracy in word-word matching, children with ASD had significantly lower emotion recognition accuracy when compared to typically developing children. The findings suggest that the social impairments observed in children with ASD are not the result of marked deficits in basic emotion recognition accuracy or longer response times. However, children with ASD may be relying on other perceptual skills (such as advanced word-word matching) to complete emotion recognition tasks at a similar level as typically developing children.
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14. Franco F, Itakura S, Pomorska K, Abramowski A, Nikaido K, Dimitriou D. {{Can children with autism read emotions from the eyes? The Eyes Test revisited}}. {Res Dev Disabil}. 2014.
This study aimed to test two new, simplified tasks related to the eye-test, targeting children with autism spectrum disorder (ASD) and typically developing controls (TD). Test-1 assessed the recognition of emotion/mental states with displays using one word and two eye-pictures, whereas Test-2 presented displays using two words and one eye-picture. Black and white photographs of children were used as materials. A cross-cultural study (Caucasian/East-Asian) with adults was initially carried out to verify generalizability across different ethnic groups. Cross-sectional trajectory analyses were used to compare emotion recognition from the eyes in the two tests. Trajectories were constructed linking performance on both tests either to chronological age or to different measures of mental age (receptive vocabulary based on the BPVS, CARS or ASQ for the ASD group). Performance improved with chronological age in both the ASD and TD groups of children. However, performance in Test-1 was significantly superior in children with ASD, who showed delayed onset and slower rate of improvement than TD children in Test-2. In both the ASD and TD groups the lowest error rate was recorded for the item ‘anger’, suggesting that threat-detection cue mechanisms may be intact in autism. In general, all children showed good performance on our novel tests, thus making them good candidates for assessing younger children and those with lower general abilities.
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15. Gjevik E, Sandstad B, Andreassen OA, Myhre AM, Sponheim E. {{Exploring the agreement between questionnaire information and DSM-IV diagnoses of comorbid psychopathology in children with autism spectrum disorders}}. {Autism}. 2014.
Autism spectrum disorders are often comorbid with other psychiatric symptoms and disorders. However, identifying psychiatric comorbidity in children with autism spectrum disorders is challenging. We explored how a questionnaire, the Child Behavior Check List, agreed with a Diagnostic and Statistical Manual of Mental Disorders-Fourth Edition (DSM-IV)-based semi-structured interview, the Kiddie-Schedule for Affective Disorders and Schizophrenia for School-Age Children (Kiddie-SADS). The sample comprised 55 children and adolescents (age 6 to 18 years) with autism spectrum disorders, including the main autism spectrum disorder subgroups and the broad range of cognitive and language functioning. High rate of psychopathology was found both through questionnaire and interview assessment. Using predefined Child Behavior Check List cutoffs, we found good agreement between the Child Behavior Check List and the Kiddie-SADS for identifying attention deficit/hyperactivity disorder, depressive disorders, and oppositional defiant disorder. However, overall the specificity of the Child Behavior Check List was low. The Child Behavior Check List was not useful for identifying anxiety disorders. The Child Behavior Check List may capture core symptoms of autism spectrum disorders as well as comorbid psychopathology, and clinicians should be aware that the Child Behavior Check List may be unspecific when used in children and adolescents with autism spectrum disorders.
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16. Goyal DK, Miyan JA. {{Neuro-Immune Abnormalities in Autism and Their Relationship with the Environment: A Variable Insult Model for Autism}}. {Front Endocrinol (Lausanne)}. 2014; 5: 29.
Autism spectrum disorder (ASD) is a heterogeneous condition affecting an individual’s ability to communicate and socialize and often presents with repetitive movements or behaviors. It tends to be severe with less than 10% achieving independent living with a marked variation in the progression of the condition. To date, the literature supports a multifactorial model with the largest, most detailed twin study demonstrating strong environmental contribution to the development of the condition. Here, we present a brief review of the neurological, immunological, and autonomic abnormalities in ASD focusing on the causative roles of environmental agents and abnormal gut microbiota. We present a working hypothesis attempting to bring together the influence of environment on the abnormal neurological, immunological, and neuroimmunological functions and we explain in brief how such pathophysiology can lead to, and/or exacerbate ASD symptomatology. At present, there is a lack of consistent findings relating to the neurobiology of autism. Whilst we postulate such variable findings may reflect the marked heterogeneity in clinical presentation and as such the variable findings may be of pathophysiological relevance, more research into the neurobiology of autism is necessary before establishing a working hypothesis. Both the literature review and hypothesis presented here explore possible neurobiological explanations with an emphasis of environmental etiologies and are presented with this bias.
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17. Han S, Tai C, Jones CJ, Scheuer T, Catterall WA. {{Enhancement of Inhibitory Neurotransmission by GABAA Receptors Having alpha2,3-Subunits Ameliorates Behavioral Deficits in a Mouse Model of Autism}}. {Neuron}. 2014; 81(6): 1282-9.
Autism spectrum disorder (ASD) may arise from increased ratio of excitatory to inhibitory neurotransmission in the brain. Many pharmacological treatments have been tested in ASD, but only limited success has been achieved. Here we report that BTBR T(+)Itpr3(tf)/J (BTBR) mice, a model of idiopathic autism, have reduced spontaneous GABAergic neurotransmission. Treatment with low nonsedating/nonanxiolytic doses of benzodiazepines, which increase inhibitory neurotransmission through positive allosteric modulation of postsynaptic GABAA receptors, improved deficits in social interaction, repetitive behavior, and spatial learning. Moreover, negative allosteric modulation of GABAA receptors impaired social behavior in C57BL/6J and 129SvJ wild-type mice, suggesting that reduced inhibitory neurotransmission may contribute to social and cognitive deficits. The dramatic behavioral improvement after low-dose benzodiazepine treatment was subunit specific-the alpha2,3-subunit-selective positive allosteric modulator L-838,417 was effective, but the alpha1-subunit-selective drug zolpidem exacerbated social deficits. Impaired GABAergic neurotransmission may contribute to ASD, and alpha2,3-subunit-selective positive GABAA receptor modulation may be an effective treatment.
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18. Henderson L, Powell A, Gareth Gaskell M, Norbury C. {{Learning and consolidation of new spoken words in autism spectrum disorder}}. {Dev Sci}. 2014.
Autism spectrum disorder (ASD) is characterized by rich heterogeneity in vocabulary knowledge and word knowledge that is not well accounted for by current cognitive theories. This study examines whether individual differences in vocabulary knowledge in ASD might be partly explained by a difficulty with consolidating newly learned spoken words and/or integrating them with existing knowledge. Nineteen boys with ASD and 19 typically developing (TD) boys matched on age and vocabulary knowledge showed similar improvements in recognition and recall of novel words (e.g. ‘biscal’) 24 hours after training, suggesting an intact ability to consolidate explicit knowledge of new spoken word forms. TD children showed competition effects for existing neighbors (e.g. ‘biscuit’) after 24 hours, suggesting that the new words had been integrated with existing knowledge over time. In contrast, children with ASD showed immediate competition effects that were not significant after 24 hours, suggesting a qualitative difference in the time course of lexical integration. These results are considered from the perspective of the dual-memory systems framework.
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19. Holmes LG, Himle MB, Sewell KK, Carbone PS, Strassberg DS, Murphy NA. {{Addressing Sexuality in Youth with Autism Spectrum Disorders: Current Pediatric Practices and Barriers}}. {J Dev Behav Pediatr}. 2014.
OBJECTIVE:: Research on adolescents and young adults with autism spectrum disorders (ASDs) has focused on promoting independence and optimizing quality of life, yet the areas of sexual development and sexuality has been largely neglected. The American Academy of Pediatrics encourages pediatricians to address sexuality issues in youth with disabilities to foster healthy development and minimize negative consequences. However, it is unclear to what extent pediatricians address sexuality issues in this population. METHODS:: Two hundred three pediatricians who regularly care for youth with ASD completed an online survey about their experiences in providing sexuality-related care to families and youth with ASD. RESULTS:: Respondents discussed an average of 10.9 of 26 sexuality topics with all families at least once during routine visits. Experience in caring for youth with ASD correlated positively with the number of sexuality-related topics discussed and with self-reported comfort discussing sexuality with parents of youth with ASD. The most common barriers to providing comprehensive sexuality-related care to youth with ASD included logistical barriers, pediatrician and parent discomfort, lack of training, and absence of information and materials to help pediatricians address sexuality in this population. CONCLUSIONS:: Although most pediatricians acknowledged the importance of addressing sexuality-related issues with youth with ASD and their families, several important sexuality-related topics were rarely discussed due to a variety of perceived barriers. Implications and recommendations are discussed.
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20. Hovey D, Zettergren A, Jonsson L, Melke J, Anckarsater H, Lichtenstein P, Westberg L. {{Associations between oxytocin-related genes and autistic-like traits}}. {Soc Neurosci}. 2014.
Oxytocin has repeatedly been shown to influence human behavior in social contexts; also, a relationship between oxytocin and the pathophysiology of autism spectrum disorder (ASD) has been suggested. In the present study, we investigated single-nucleotide polymorphisms (SNPs) in the oxytocin gene (OXT) and the genes for single-minded 1 (SIM1), aryl hydrocarbon receptor nuclear translocator 2 (ARNT2) and cluster of differentiation 38 (CD38) in a population of 1771 children from the Child and Adolescent Twin Study in Sweden (CATSS). Statistical analyses were performed to investigate any association between SNPs and autistic-like traits (ALTs), measured through ASD scores in the Autism-Tics, ADHD and other Co-morbidities inventory. Firstly, we found a statistically significant association between the SIM1 SNP rs3734354 (Pro352Thr) and scores for language impairment (p = .0004), but due to low statistical power this should be interpreted cautiously. Furthermore, nominal associations were found between ASD scores and SNPs in OXT, ARNT2 and CD38. In summary, the present study lends support to the hypothesis that oxytocin and oxytocin neuron development may have an influence on the development of ALTs and suggests a new candidate gene in the search for the pathophysiology of ASD.
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21. Hubbard KL, Bandini LG, Folta SC, Wansink B, Eliasziw M, Must A. {{Impact of a Smarter Lunchroom intervention on food selection and consumption among adolescents and young adults with intellectual and developmental disabilities in a residential school setting}}. {Public Health Nutr}. 2014: 1-11.
OBJECTIVE: To assess whether a Smarter Lunchroom intervention based on behavioural economics and adapted for students with intellectual and developmental disabilities would increase the selection and consumption of fruits, vegetables and whole grains, and reduce the selection and consumption of refined grains. DESIGN: The 3-month intervention took place at a residential school between March and June 2012. The evaluation employed a quasi-experimental, pre-post design comparing five matched days of dietary data. Selection and plate waste of foods at lunch were assessed using digital photography. Consumption was estimated from plate waste. SETTING: Massachusetts, USA. SUBJECTS: Students (n 43) aged 11-22 years with intellectual and developmental disabilities attending a residential school. RESULTS: Daily selection of whole grains increased by a mean of 0.44 servings (baseline 1.62 servings, P = 0.005) and refined grains decreased by a mean of 0.33 servings (baseline 0.82 servings, P = 0.005). The daily consumption of fruits increased by a mean of 0.18 servings (baseline 0.39 servings, P = 0.008), whole grains increased by 0.38 servings (baseline 1.44 servings, P = 0.008) and refined grains decreased by a mean of 0.31 servings (baseline 0.68 servings, P = 0.004). Total kilojoules and total gram weight of food selected and consumed were unchanged. Fruit (P = 0.04) and vegetable (P = 0.03) plate waste decreased. CONCLUSIONS: A Smarter Lunchroom intervention significantly increased whole grain selection and consumption, reduced refined grain selection and consumption, increased fruit consumption, and reduced fruit and vegetable plate waste. Nudge approaches may be effective for improving the food selection and consumption habits of adolescents and young adults with intellectual and developmental disabilities.
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22. Iovchuk NM, Severnyi AA. {{[The problems of diagnosis and correction of autism in children (an example of Asperger’s syndrome).]}}. {Zh Nevrol Psikhiatr Im S S Korsakova}. 2014; 114(1 Vypusk 2 Detskaia nevrologiia i psikhiatriia): 15-9.
Based on the analysis of literature and own clinical experience, we discicuss diagnostic issues of early autistic disorders in children. Main differential-diagnostic signs that permit to differentiate mild forms of autism in childhood diagnosed as Asperger’s syndrome from childhood schizophrenia, residual organic CNS damage, circular affective disorders are described. Cases of Asperger’s syndrome followed up for many years and recommendations for social and psychological adaptation of children and adolescents with Asperger’s syndrome in different age periods are presented.
23. Karalunas SL, Geurts HM, Konrad K, Bender S, Nigg JT. {{Annual Research Review: Reaction time variability in ADHD and autism spectrum disorders: measurement and mechanisms of a proposed trans-diagnostic phenotype}}. {J Child Psychol Psychiatry}. 2014.
BACKGROUND: Intraindividual variability in reaction time (RT) has received extensive discussion as an indicator of cognitive performance, a putative intermediate phenotype of many clinical disorders, and a possible trans-diagnostic phenotype that may elucidate shared risk factors for mechanisms of psychiatric illnesses. SCOPE AND METHODOLOGY: Using the examples of attention deficit hyperactivity disorder (ADHD) and autism spectrum disorders (ASD), we discuss RT variability. We first present a new meta-analysis of RT variability in ASD with and without comorbid ADHD. We then discuss potential mechanisms that may account for RT variability and statistical models that disentangle the cognitive processes affecting RTs. We then report a second meta-analysis comparing ADHD and non-ADHD children on diffusion model parameters. We consider how findings inform the search for neural correlates of RT variability. FINDINGS: Results suggest that RT variability is increased in ASD only when children with comorbid ADHD are included in the sample. Furthermore, RT variability in ADHD is explained by moderate to large increases (d = 0.63-0.99) in the ex-Gaussian parameter tau and the diffusion parameter drift rate, as well as by smaller differences (d = 0.32) in the diffusion parameter of nondecision time. The former may suggest problems in state regulation or arousal and difficulty detecting signal from noise, whereas the latter may reflect contributions from deficits in motor organization or output. The neuroimaging literature converges with this multicomponent interpretation and also highlights the role of top-down control circuits. CONCLUSION: We underscore the importance of considering the interactions between top-down control, state regulation (e.g. arousal), and motor preparation when interpreting RT variability and conclude that decomposition of the RT signal provides superior interpretive power and suggests mechanisms convergent with those implicated using other cognitive paradigms. We conclude with specific recommendations for the field for next steps in the study of RT variability in neurodevelopmental disorders.
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24. Kealey C. {{Autism spectrum disorder: importance of audiology}}. {CMAJ}. 2014; 186(5): 372.
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25. Kornmeier J, Worner R, Riedel A, Bach M, Tebartz van Elst L. {{A different view on the checkerboard? Alterations in early and late visually evoked EEG potentials in asperger observers}}. {PLoS One}. 2014; 9(3): e90993.
BACKGROUND: Asperger Autism is a lifelong psychiatric condition with highly circumscribed interests and routines, problems in social cognition, verbal and nonverbal communication, and also perceptual abnormalities with sensory hypersensitivity. To objectify both lower-level visual and cognitive alterations we looked for differences in visual event-related potentials (EEG) between Asperger observers and matched controls while they observed simple checkerboard stimuli. METHODS: In a balanced oddball paradigm checkerboards of two checksizes (0.6 degrees and 1.2 degrees ) were presented with different frequencies. Participants counted the occurrence times of the rare fine or rare coarse checkerboards in different experimental conditions. We focused on early visual ERP differences as a function of checkerboard size and the classical P3b ERP component as an indicator of cognitive processing. RESULTS: We found an early (100-200 ms after stimulus onset) occipital ERP effect of checkerboard size (dominant spatial frequency). This effect was weaker in the Asperger than in the control observers. Further a typical parietal/central oddball-P3b occurred at 500 ms with the rare checkerboards. The P3b showed a right-hemispheric lateralization, which was more prominent in Asperger than in control observers. DISCUSSION: The difference in the early occipital ERP effect between the two groups may be a physiological marker of differences in the processing of small visual details in Asperger observers compared to normal controls. The stronger lateralization of the P3b in Asperger observers may indicate a stronger involvement of the right-hemispheric network of bottom-up attention. The lateralization of the P3b signal might be a compensatory consequence of the compromised early checksize effect. Higher-level analytical information processing units may need to compensate for difficulties in low-level signal analysis.
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26. Lane AE, Molloy CA, Bishop SL. {{Classification of Children With Autism Spectrum Disorder by Sensory Subtype: A Case for Sensory-Based Phenotypes}}. {Autism Res}. 2014.
This study examines whether sensory differences can be used to classify meaningful subgroups of children with autism spectrum disorder (ASD). Caregivers of children with ASD aged 2-10 years (n = 228) completed the Short Sensory Profile. Model-based cluster analysis was used to extract sensory subtypes. The relationship of these subtypes to age, gender, autism symptom severity, and nonverbal intelligence quotient (IQ) was further explored. Four distinct sensory subtypes were identified: (a) sensory adaptive; (b) taste smell sensitive; (c) postural inattentive; and (d) generalized sensory difference. The sensory subtypes differ from each other on two dimensions: (a) the severity of reported sensory differences; and (b) the focus of differences across auditory, taste, smell, vestibular and proprioceptive domains. Examination of the clinical features of each subtype reveals two possible mechanisms of sensory disturbance in autism: (a) sensory hyperreactivity; and (b) difficulties with multisensory processing. Further, the sensory subtypes are not well explained by other variables such as age, gender, IQ, and autism symptom severity. We conclude that classification of children using sensory differences offers a promising method by which to identify phenotypes in ASD. Sensory-based phenotypes may be useful in identifying behavioral features responsive to specific interventions thereby improving intervention effectiveness. Further validation of the sensory-based phenotypes by establishing neural and physiological correlates is recommended. Autism Res 2014, : -. (c) 2014 International Society for Autism Research, Wiley Periodicals, Inc.
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27. Li Y, Zhao X. {{Fragile X proteins in stem cell maintenance and differentiation}}. {Stem Cells}. 2014.
Fragile X syndrome (FXS), the most common genetic form of autism spectrum disorder, is caused by deficiency of the fragile X mental retardation protein (FMRP). Despite extensive research and scientific progress, understanding how FMRP regulates brain development and function remains a major challenge. FMRP is a neuronal RNA-binding protein that binds about a third of messenger RNAs in the brain and controls their translation, stability, and cellular localization. The absence of FMRP results in increased protein synthesis, leading to enhanced signaling in a number of intracellular pathways, including the mTOR, mGLuR5, ERK, Gsk3beta, PI3K, and insulin pathways. Until recently, FXS was largely considered a deficit of mature neurons; however, a number of new studies have shown that FMRP may also play important roles in stem cells, among them neural stem cells, germ line stem cells, and pluripotent stem cells. In this review, we will cover these newly discovered functions of FMRP, as well as the other two fragile X-related proteins, in stem cells. We will also discuss the literature on the use of stem cells, particularly neural stem cells and induced pluripotent stem cells, as model systems for studying the functions of FMRP in neuronal development. Stem Cells 2014.
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28. Lionello-Denolf KM, Farber R, Jones BM, Dube WV. {{Thematic Matching as Remedial Teaching for Symbolic Matching for Individuals with Autism Spectrum Disorder}}. {Res Autism Spectr Disord}. 2014; 8(5): 455-62.
Matching-to-sample (MTS) is often used to teach symbolic relationships between spoken or printed words and their referents to children with intellectual and developmental disabilities. However, many children have difficulty learning symbolic matching, even though they may demonstrate generalized identity matching. The current study investigated whether training on symbolic MTS tasks in which the stimuli are physically dissimilar but members of familiar categories (i.e., thematic matching) can remediate an individual’s difficulty learning symbolic MTS tasks involving non-representative stimuli. Three adolescent males diagnosed with autism spectrum disorder were first trained on symbolic MTS tasks with unfamiliar, non-representative form stimuli. Thematic matching was introduced after the participants failed to learn 0, 2 or 4 symbolic MTS tasks and before additional symbolic MTS tasks were introduced. After exposure to thematic matching, accuracy on symbolic MTS tasks with novel stimuli increased to above chance for all participants. For two participants, high accuracy (> 90%) was achieved on a majority of these sessions. Thus, thematic matching may be an effective intervention for students with limited verbal repertoires and who have difficulty learning symbolic MTS tasks. Possible explanations for the facilitative effect of thematic matching are considered and warrant further investigation.
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29. Luo S, Huang W, Chen C, Pan Q, Duan R, Wu L. {{A novel deletion to normal size in the sperm of a fragile X full mutation male}}. {Clin Genet}. 2013.
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30. Lyons M, Schoen Simmons E, Paul R. {{Prosodic Development in Middle Childhood and Adolescence in High-Functioning Autism}}. {Autism Res}. 2014.
The present study aims to investigate the perception and production of several domains of prosodic performance in a cross-sectional sample of preadolescents and adolescents with and without high-functioning autism (HFA). To look at the role of language abilities on prosodic performance, the HFA groups were subdivided based on « high » and « low » language performance on the Clinical Evaluation of Language Fundamentals-Fourth Edition (CELF-4) (Semel, Wiig, & Secord). Social and cognitive abilities were also examined to determine their relationship to prosodic performance. No significant differences were seen in prosody scores in the younger versus older subgroups in typically developing (TD) group with age-appropriate language. There was small but significant improvement in performance with age in the groups with HFA. Comparing performance at each age level across diagnostic groups showed that preteens with HFA and higher language levels perform similarly to their TD peers on all prosodic tasks, whereas those with lower language skills scored significantly worse than both their higher language and TD peers when looking at composite perception and production findings. Teens with HFA showed no deficits on perception tasks; however, those with low language levels had difficulty on several production tasks when compared to the TD group. Regression analyses suggested that, for the preteen group with HFA, language was the strongest predictor of prosodic perception, whereas nonverbal IQ was most highly predictive of prosodic production. For adolescents with HFA, social skills significantly contributed to the prediction of prosodic perception and, along with language abilities, predicted prosodic production. Implications of these findings will be discussed. Autism Res 2014, : -. (c) 2014 International Society for Autism Research, Wiley Periodicals, Inc.
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31. Matson JL, Cervantes PE. {{Commonly studied comorbid psychopathologies among persons with autism spectrum disorder}}. {Res Dev Disabil}. 2014.
The study of comorbid psychopathology among persons with autism spectrum disorder (ASD) is picking up steam. The purpose of this paper was to review and describe important characteristics of existing studies. Among the current crop of papers, depression, anxiety, and attention-deficit/hyperactivity disorder (ADHD) have been frequently evaluated. Groups studied have most frequently been children. Persons with ASD and normal intelligence quotient (IQ) scores have been studied more often than individuals with ASD and intellectual disability. Additional characteristics are discussed, and the implications of these data for future developments in the field are reviewed.
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32. McGillivray JA, Evert HT. {{Group Cognitive Behavioural Therapy Program Shows Potential in Reducing Symptoms of Depression and Stress Among Young People with ASD}}. {J Autism Dev Disord}. 2014.
We examined the efficacy of cognitive behavioural therapy (CBT) delivered in groups on the reduction of symptoms of depression, anxiety and stress in young people on the autism spectrum. Utilising a quasi-experimental design, comparisons were made between individuals allocated to a group intervention program and individuals allocated to a waitlist. Following the intervention program, participants who were initially symptomatic reported significantly lower depression and stress scores on the Depression Anxiety Stress Scales in comparison to individuals on the waitlist. There was no significant change in anxiety related symptoms. The benefits were maintained at 3 and 9 month follow-up. Our findings demonstrate the potential of CBT in a small group setting for assisting young people with ASD who have symptoms of depression and stress.
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33. Meaux E, Taylor MJ, Pang EW, Vara AS, Batty M. {{Neural substrates of numerosity estimation in autism}}. {Hum Brain Mapp}. 2014.
Visual skills, including numerosity estimation are reported to be superior in autism spectrum disorders (ASD). This phenomenon is attributed to individuals with ASD processing local features, rather than the Gestalt. We examined the neural correlates of numerosity estimation in adults with and without ASD, to disentangle perceptual atypicalities from numerosity processing. Fourteen adults with ASD and matched typically developed (TD) controls estimated the number of dots (80-150) arranged either randomly (local information) or in meaningful patterns (global information) while brain activity was recorded with magnetoencephalography (MEG). Behavioral results showed no significant group difference in the errors of estimation. However, numerical estimation in ASD was more variable across numerosities than TD and was not affected by the global arrangement of the dots. At 80-120 ms, MEG analyses revealed early significant differences (TD > ASD) in source amplitudes in visual areas, followed from 120 to 400 ms by group differences in temporal, and then parietal regions. After 400 ms, a source was found in the superior frontal gyrus in TD only. Activation in temporal areas was differently sensitive to the global arrangement of dots in TD and ASD. MEG data show that individuals with autism exhibit widespread functional abnormalities. Differences in temporal regions could be linked to atypical global perception. Occipital followed by parietal and frontal differences might be driven by abnormalities in the processing and conversion of visual input into a number-selective neural code and complex cognitive decisional stages. These results suggest overlapping atypicalities in sensory, perceptual and number-related processing during numerosity estimation in ASD. Hum Brain Mapp, 2014. (c) 2014 Wiley Periodicals, Inc.
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34. Milton DE. {{Autistic expertise: A critical reflection on the production of knowledge in autism studies}}. {Autism}. 2014.
The field of autism studies is a highly disputed territory within which competing contradictory discourses abound. In this field, it is the voices and claims of autistic people regarding their own expertise in knowledge production concerning autism that is most recent in the debate, and traditionally the least attended to. In this article, I utilise the theories of Harry Collins and colleagues in order to reflect upon and conceptualise the various claims to knowledge production and expertise within the field of autism studies, from the perspective of an author who has been diagnosed as being on the autism spectrum. The notion that autistic people lack sociality is problematised, with the suggestion that autistic people are not well described by notions such as the ‘social brain’, or as possessing ‘zero degrees of cognitive empathy’. I then argue, however, that there is a qualitative difference in autistic sociality, and question to what extent such differences are of a biological or cultural nature, and to what extent interactional expertise can be gained by both parties in interactions between autistic and non-autistic people. In conclusion, I argue that autistic people have often become distrustful of researchers and their aims, and are frequently frozen out of the processes of knowledge production. Such a context results in a negative feedback spiral with further damage to the growth of interactional expertise between researchers and autistic people, and a breakdown in trust and communication leading to an increase in tension between stakeholder groups. The involvement of autistic scholars in research and improvements in participatory methods can thus be seen as a requirement, if social research in the field of autism is to claim ethical and epistemological integrity.
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35. Nishijo M, Pham TT, Nguyen AT, Tran NN, Nakagawa H, Hoang LV, Tran AH, Morikawa Y, Ho MD, Kido T, Nguyen MN, Nguyen HM, Nishijo H. {{2,3,7,8-Tetrachlorodibenzo-p-dioxin in breast milk increases autistic traits of 3-year-old children in Vietnam}}. {Mol Psychiatry}. 2014.
Dioxin levels in the breast milk of mothers residing near a contaminated former airbase in Vietnam remain much higher than in unsprayed areas, suggesting high perinatal dioxin exposure for their infants. The present study investigated the association of perinatal dioxin exposure with autistic traits in 153 3-year-old children living in a contaminated area in Vietnam. The children were followed up from birth using the neurodevelopmental battery Bayley-III. The high-2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) exposed groups (>/=3.5 pg per g fat) showed significantly higher Autism Spectrum Rating Scale (ASRS) scores for both boys and girls than the mild-TCDD exposed groups, without differences in neurodevelopmental scores. In contrast, the high total dioxin-exposed group, indicated by polychlorinated dibenzo-p-dioxins/furans (PCDDs/Fs)-the toxic equivalents (TEQ) levels>/=17.9 pg-TEQ per g fat, had significantly lower neurodevelopmental scores than the mild-exposed group in boys, but there was no difference in the ASRS scores. The present study demonstrates a specific impact of perinatal TCDD on autistic traits in childhood, which is different from the neurotoxicity of total dioxins (PCDDs/Fs).Molecular Psychiatry advance online publication, 18 March 2014; doi:10.1038/mp.2014.18.
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36. O’Nions E, Sebastian CL, McCrory E, Chantiluke K, Happe F, Viding E. {{Neural bases of Theory of Mind in children with autism spectrum disorders and children with conduct problems and callous-unemotional traits}}. {Dev Sci}. 2014.
Individuals with autism spectrum disorders (ASD) have difficulty understanding other minds (Theory of Mind; ToM), with atypical processing evident at both behavioural and neural levels. Individuals with conduct problems and high levels of callous-unemotional (CU) traits (CP/HCU) exhibit reduced responsiveness to others’ emotions and difficulties interacting with others, but nonetheless perform normally in experimental tests of ToM. The present study aimed to examine the neural underpinnings of ToM in children (aged 10-16) with ASD (N = 16), CP/HCU (N = 16) and typically developing (TD) controls (N = 16) using a non-verbal cartoon vignette task. Whilst individuals with ASD were predicted to show reduced fMRI responses across regions involved in ToM processing, CP/HCU individuals were predicted to show no differences compared with TD controls. The analyses indicated that neural responses did not differ between TD and CP/HCU groups during ToM. TD and CP/HCU children exhibited significantly greater medial prefrontal cortex responses during ToM than did the ASD group. Within the ASD group, responses in medial prefrontal cortex and right temporoparietal junction (TPJ) correlated with symptom severity as measured by the Autism Diagnostic Observation Schedule (ADOS). Findings suggest that although both ASD and CP/HCU are characterized by social difficulties, only children with ASD display atypical neural processing associated with ToM.
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37. Quintero AI, Beaton EA, Harvey DJ, Ross JL, Simon TJ. {{Common and specific impairments in attention functioning in girls with chromosome 22q11.2 deletion, fragile X or Turner syndromes}}. {J Neurodev Disord}. 2014; 6(1): 5.
BACKGROUND: Chromosome 22q11.2 deletion syndrome (22q11.2DS), fragile X syndrome (FXS), and Turner syndrome (TS) are complex and variable developmental syndromes caused by different genetic abnormalities; yet, they share similar cognitive impairments in the domains of numbers, space, and time. The atypical development of foundational neural networks that underpin the attentional system is thought to result in further impairments in higher-order cognitive functions. The current study investigates whether children with similar higher-order cognitive impairments but different genetic disorders also show similar impairments in alerting, orienting, and executive control of attention. METHODS: Girls with 22q11.2DS, FXS, or TS and typically developing (TD) girls, aged 7 to 15 years, completed an attention network test, a flanker task with alerting and orienting cues. Exploration of reaction times and accuracy allowed us to test for potential commonalities in attentional functioning in alerting, orienting, and executive control. Linear regression models were used to test whether the predictors of group and chronological age were able to predict differences in attention indices. RESULTS: Girls with 22q11.2DS, FXS, or TS demonstrated unimpaired function of the alerting system and impaired function of the executive control system. Diagnosis-specific impairments were found such that girls with FXS made more errors and had a reduced orienting index, while girls with 22q11.2DS showed specific age-related deficits in the executive control system. CONCLUSIONS: These results suggest that the control but not the implementation of attention is selectively impaired in girls with 22q11.2DS, TS or FXS. Additionally, the age effect on executive control in girls with 22q11.2DS implies a possible altered developmental trajectory.
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38. Renoux AJ, Sala-Hamrick KJ, Carducci NM, Frazer M, Halsey KE, Sutton MA, Dolan DF, Murphy GG, Todd PK. {{Impaired sensorimotor gating in Fmr1 knock out and Fragile X premutation model mice}}. {Behav Brain Res}. 2014.
Fragile X syndrome (FXS) is a common inherited cause of intellectual disability that results from a CGG repeat expansion in the FMR1 gene. Large repeat expansions trigger both transcriptional and translational suppression of Fragile X protein (FMRP) production. Fragile X-associated Tremor/Ataxia Syndrome (FXTAS) is an allelic neurodegenerative disease caused by smaller « pre-mutation » CGG repeat expansions that enhance FMR1 transcription but lead to translational inefficiency and reduced FMRP expression in animal models. Sensorimotor gating as measured by pre-pulse inhibition (PPI) is altered in both FXS patients and Fmr1 knock out (KO) mice. Similarly, FXTAS patients have demonstrated PPI deficits. Recent work suggests there may be overlapping synaptic defects between Fmr1 KO and CGG knock-in premutation mouse models (CGG KI). We therefore sought to interrogate PPI in CGG KI mice. Using a quiet PPI protocol more akin to human testing conditions, we find that Fmr1 KO animals have significantly impaired PPI. Using this same protocol, we find CGG KI mice demonstrate an age-dependent impairment in PPI compared to wild type (WT) controls. This study describes a novel phenotype in CGG KI mice that can be used in future therapeutic development targeting premutation associated symptoms.
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39. Schwarzkopf S, Schilbach L, Vogeley K, Timmermans B. {{« Making it explicit » makes a difference: Evidence for a dissociation of spontaneous and intentional level 1 perspective taking in high-functioning autism}}. {Cognition}. 2014; 131(3): 345-54.
The ability of perspective taking is a fundamental aspect of social cognition. The ability to decide, what another person can or cannot see is referred to as « level 1 perspective taking. » This is thought to be a process that we can make use of intentionally, but which also takes place spontaneously. Autism is characterized by impairments of social interaction, which are thought to be related to deficits in implicit rather than explicit perspective taking. In order to assess both levels of processing with regard to perspective taking, we employed an established task in patients and controls. Our results demonstrate that both groups engage in spontaneous level 1 perspective taking. In contrast to controls, however, patients reacted more slowly if they had to verify the other’s as compared to their own perspective, which shows that participants with high-functioning autism have selective difficulties in explicit, but not implicit, level 1 perspective taking. These findings demonstrate that while spontaneous level 1 perspective taking appears to be intact in autism, this ability is impaired in patients when used explicitly.
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40. Sheppard JJ, Hochman R, Baer C. {{The Dysphagia Disorder Survey: Validation of an assessment for swallowing and feeding function in developmental disability}}. {Res Dev Disabil}. 2014.
Swallowing and feeding disorder (dysphagia) have high incidence and prevalence in children and adults with developmental disability. Standardized screening and clinical assessments are needed to identify and describe the disorder. The aim of this study was to describe the psychometric properties of the Dysphagia Disorder Survey (DDS), a screening and clinical assessment of swallowing and feeding function for eating and drinking developed specifically for this population. The statistical analysis was performed on a sample of 654 individuals (age range 8-82) with intellectual and developmental disability living in two residential settings in the United States that served somewhat different populations. The two samples had similar factor structures. Internal consistency of the DDS and subscales was confirmed using Chronbach’s coefficient alpha. The DDS demonstrated convergent validity when compared to judgments of swallowing and feeding disorder severity made by clinical swallowing specialists. Discriminative validity for severity of disorder was tested by comparing the two samples. The results of the study suggest that the DDS is a reliable and valid test for identifying and describing swallowing and feeding disorder in children and adults with developmental disability.
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41. Stortz JN, Lake JK, Cobigo V, Ouellette-Kuntz HM, Lunsky Y. {{Lessons learned from our elders: how to study polypharmacy in populations with intellectual and developmental disabilities}}. {Intellect Dev Disabil}. 2014; 52(1): 60-77.
Abstract Polypharmacy is the concurrent use of multiple medications, including both psychotropic and non-psychotropic drugs. Although it may sometimes be clinically indicated, polypharmacy can have a number of negative consequences, including medication nonadherence, adverse drug reactions, and undesirable drug-drug interactions. The objective of this paper was to gain a better understanding of how to study polypharmacy among people with intellectual and developmental disabilities (IDD). To do this, we reviewed literature on polypharmacy among the elderly and people with IDD to inform future research approaches and methods on polypharmacy in people with IDD. Results identified significant variability in methods used to study polypharmacy, including definitions of polypharmacy, samples studied, analytic strategies, and variables included in the analyses. Four valuable methodological lessons to strengthen future polypharmacy research in individuals with IDD emerged. These included the use of consistent definitions of polypharmacy, the implementation of population-based sampling strategies, the development of clinical guidelines, and the importance of studying associated variables.
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42. Thurman AJ, McDuffie A, Hagerman R, Abbeduto L. {{Psychiatric symptoms in boys with fragile X syndrome: A comparison with nonsyndromic autism spectrum disorder}}. {Res Dev Disabil}. 2014.
In the present study, we examined the profile of psychiatric symptoms in boys with fragile X syndrome (FXS) using a parent report instrument. In addition, by comparing boys with FXS to boys with nonsyndromic autism spectrum disorder (ASD) utilizing multiple matching strategies, we examined between-group differences in the types of psychiatric symptoms observed and in the strength of their concurrent associations. Across all matching strategies, symptoms of manic/hyperactive behaviors and general anxiety were more frequently reported for boys with FXS than for boys with nonsyndromic ASD. Results also indicated a positive association between social avoidance and general anxiety in FXS that was stronger than that observed in nonsyndromic ASD across all matching strategies. Theoretical and treatment implications are discussed.
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43. Wen W, Wen SW. {{Expanding upon the ‘extreme male brain’ theory of autism as a common link between other major risk factors: A hypothesis}}. {Med Hypotheses}. 2014.
On average, males have a stronger preference for physical systems and machines over interpersonal interactions; they have lower average levels of cognitive empathy or social cognition than females; and they have higher rates of ‘extreme’ intelligence when it comes to abstract concepts such as those found in mathematics and sciences. All three traits are also commonly associated with individuals with an autism spectrum disorder or ASD; clearly, it is not coincidental that incidence rates of autism are reportedly four times higher in males than in females. The common link between the majority of risk factors assessed in this review (including technological advancements, advanced parental age, socioeconomic status, and genetic predispositions towards ASDs in families of scientists and engineers) can be traced to a specific hormone, testosterone. It was established that traits which are typically associated with males are also typically associated with ASDs as well as individuals with antisocial personality disorder, or APD. The key distinction between individuals who are considered to be ‘autistic’ as opposed to those who are considered ‘sociopathic’ lies in the difference between their empathy deficits: whereas those who are ‘autistic’ are said to lack cognitive empathy (the ability to identify and understand the thoughts and feelings of others and to respond to these with appropriate emotions), those who are ‘sociopathic’ are said to lack emotional empathy (which is responsible for inhibiting acts of physical aggression or violence). This would explain why autistic individuals can have elevated testosterone levels without becoming physically aggressive.
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44. Xu X, Kozikowski AP, Pozzo-Miller L. {{A selective histone deacetylase-6 inhibitor improves BDNF trafficking in hippocampal neurons from Mecp2 knockout mice: implications for Rett syndrome}}. {Front Cell Neurosci}. 2014; 8: 68.
Rett syndrome (RTT) is a neurodevelopmental disorder caused by loss-of-function mutations in the transcriptional modulator methyl-CpG-binding protein 2 (MECP2). One of the most prominent gene targets of MeCP2 is brain-derived neurotrophic factor (Bdnf), a potent modulator of activity-dependent synaptic development, function and plasticity. Dysfunctional BDNF signaling has been demonstrated in several pathophysiological mechanisms of RTT disease progression. To evaluate whether the dynamics of BDNF trafficking is affected by Mecp2 deletion, we analyzed movements of BDNF tagged with yellow fluorescent protein (YFP) in cultured hippocampal neurons by time-lapse fluorescence imaging. We found that both anterograde and retrograde vesicular trafficking of BDNF-YFP are significantly impaired in Mecp2 knockout hippocampal neurons. Selective inhibitors of histone deacetylase 6 (HDAC6) show neuroprotective effects in neurodegenerative diseases and stimulate microtubule-dependent vesicular trafficking of BDNF-containing dense core vesicles. Here, we show that the selective HDAC6 inhibitor Tubastatin-A increased the velocity of BDNF-YFP vesicles in Mecp2 knockout neurons in both directions by increasing alpha-tubulin acetylation. Tubastatin-A also restored activity-dependent BDNF release from Mecp2 knockout neurons to levels comparable to those shown by wildtype neurons. These findings demonstrate that a selective HDAC6 inhibitor is a potential pharmacological strategy to reverse cellular and synaptic impairments in RTT resulting from impaired BDNF signaling.
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45. Yin A, Qiu Y, Jia B, Song T, Yu Y, Alberts I, Zhong M. {{The developmental pattern of the RAS/RAF/Erk1/2 pathway in the BTBR autism mouse model}}. {Int J Dev Neurosci}. 2014.
BTBR mice exhibit several autistic-like behaviors and are currently used as a model for understanding mechanisms that may be responsible for the pathogenesis of autism. Ras/Raf/ERK1/2 signaling has been suggested to play an important role in neural development, learning, memory, and cognition. Two studies reported that a deletion of a locus on chromosome 16 containing the mitogen-activated protein kinase 3 (MAPK3) gene, which encodes ERK1, is associated with autism. In the present study, Ras/Raf/ERK1/2 signaling was found to be up-regulated in BTBR mice relative to matched control B6 mice, to further suggest involvement in the pathogenesis of autism. To further characterize the developmental pattern of Ras/Raf/ERK1/2 signaling, varying stages during development were sampled to reveal an up-regulation in newborn and 2-week old BTBR mice relative to age-matched B6 mice. By the age of 3-week, Ras/Raf/ERK1/2 signaling in the brain of BTBR mice was unaltered relative to B6 mice, with this trend maintained in 6-week samples. These results suggest that the alteration of Ras/Raf/ERK signaling in the early developmental stages in mice could contribute to the noted autistic phenotype. Furthermore, these findings support the value of BTBR mice to serve as a human analogue for autistic etiological research and aid in a better understanding of the developmental mechanisms of autism.
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46. Yoon JM, Vouloumanos A. {{When and how does autism begin?}}. {Trends Cogn Sci}. 2014.
Jones and Klin recently found that the well-known decreased fixations to eyes in children with autism spectrum disorder (ASD) are not present throughout infancy; instead a decline in eye fixations between 2 and 6 months predicts diagnosis. This decline is the earliest behavioral pattern linked to autism to date.
