1. Bi T, Fang F. {{Impaired Face Perception in Individuals with Autism Spectrum Disorder: Insights on Diagnosis and Treatment}}. {Neurosci Bull}. 2017.
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2. Brezis RS, Noy L, Alony T, Gotlieb R, Cohen R, Golland Y, Levit-Binnun N. {{Patterns of Joint Improvisation in Adults with Autism Spectrum Disorder}}. {Front Psychol}. 2017; 8: 1790.
Recent research on autism spectrum disorders (ASDs) suggests that individuals with autism may have a basic deficit in synchronizing with others, and that this difficulty may lead to more complex social and communicative deficits. Here, we examined synchronization during an open-ended joint improvisation (JI) paradigm, called the mirror game (MG). In the MG, two players take turns leading, following, and jointly improvising motion using two handles set on parallel tracks, while their motion tracks are recorded with high temporal and spatial resolution. A series of previous studies have shown that players in the MG attain moments of highly synchronized co-confident (CC) motion, in which there is no typical kinematic pattern of leader and reactive follower. It has been suggested that during these moments players act as a coupled unit and feel high levels of connectedness. Here, we aimed to assess whether participants with ASD are capable of attaining CC, and whether their MG performance relates to broader motor and social skills. We found that participants with ASD (n = 34) can indeed attain CC moments when playing with an expert improviser, though their performance was attenuated in several ways, compared to typically developing (TD) participants (n = 35). Specifically, ASD participants had lower rates of CC, compared with TD participants, which was most pronounced during the following rounds. In addition, the duration of their CC segments was shorter, across all rounds. When controlling for participants’ motor skills (both on the MG console, and more broadly) some of the variability in MG performance was explained, but group differences remained. ASD participants’ alexithymia further correlated with their difficulty following another’s lead; though other social skills did not relate to MG performance. Participants’ subjective reports of the game suggest that other cognitive and emotional factors, such as attention, motivation, and reward-processing, which were not directly measured in the experiment, may impact their performance. Together, these results show that ASD participants can attain moments of high motor synchronization with an expert improviser, even during an open-ended task. Future studies should examine the ways in which these skills may be further harnessed in clinical settings.
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3. Chistol LT, Bandini LG, Must A, Phillips S, Cermak SA, Curtin C. {{Sensory Sensitivity and Food Selectivity in Children with Autism Spectrum Disorder}}. {J Autism Dev Disord}. 2017.
Few studies have compared atypical sensory characteristics and food selectivity between children with and without autism spectrum disorder (ASD). We compared oral sensory processing between children with (n = 53) and without ASD (n = 58), ages 3-11 years. We also examined the relationships between atypical oral sensory processing, food selectivity, and fruit/vegetable consumption in children with ASD. We found that more children with ASD presented with atypical sensory processing than children without ASD. Among children with ASD, those with atypical oral sensory sensitivity refused more foods and ate fewer vegetables than those with typical oral sensory sensitivity. The findings suggest that efforts to address food selectivity in children with ASD may be enhanced by including strategies that address oral sensory processing.
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4. Di X, Azeez A, Li X, Haque E, Biswal BB. {{Disrupted focal white matter integrity in autism spectrum disorder: A voxel-based meta-analysis of diffusion tensor imaging studies}}. {Prog Neuropsychopharmacol Biol Psychiatry}. 2017.
BACKGROUND: Autism spectrum disorder (ASD) is a mental disorder that has long been considered to result from brain underconnectivity. However, volumetric analysis of structural MRI data has failed to find consistent white matter alterations in patients with ASD. The present study aims to examine whether there are consistent focal white matter alterations as measured by diffusion tensor imaging (DTI) in individuals with ASD compared with typically developing (TD) individuals. METHOD: Coordinate-based meta-analysis was performed on 14 studies that reported fractional anisotropy (FA) alterations between individuals with ASD and TD individuals. These studies have in total 297 subjects with ASD and 302 TD subjects. RESULTS: Activation likelihood estimation (ALE) analysis identified two clusters of white matter regions that showed consistent reduction of FA in individuals with ASD compared with TD individuals: the left splenium of corpus callosum and the right cerebral peduncle. CONCLUSIONS: Consistent focal white matter reductions in ASD could be identified by using FA, highlighting the cerebral peduncle which is usually overlooked in studies focusing on major white matter tracts. These focal reductions in the splenium and the cerebral peduncle may be associated with sensorimotor impairments seen in individuals with ASD.
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5. Goodrich AJ, Volk HE, Tancredi DJ, McConnell R, Lurmann FW, Hansen RL, Schmidt RJ. {{Joint effects of prenatal air pollutant exposure and maternal folic acid supplementation on risk of autism spectrum disorder}}. {Autism Res}. 2017.
Independent studies report that periconceptional folic acid (FA) may decrease the risk of autism spectrum disorder (ASD) while exposure to air pollution may increase ASD risk. We examined the joint effects of gestational FA and air pollution exposures in association with ASD. We studied 346 ASD cases and 260 typically developing controls from the CHARGE case-control study. Self-reported FA intake for each month of pregnancy was quantified. Estimates of exposure to near roadway air pollution (NRP) and criteria air pollutant measures were assigned based on maternal residential history. Among mothers with high FA intake (>800 mug) in the first pregnancy month, exposure to increasing levels of all air pollutants, except ozone, during the first trimester was associated with decreased ASD risk, while increased ASD risk was observed for the same pollutant among mothers with low FA intake (/= median) of any air pollutant during the first trimester of pregnancy and who reported low FA intake were at a higher ASD risk compared to mothers exposed to lower levels of that air pollutant and who reported high first month FA intake. Joint effects showed significant (alpha < 0.10) departures from expected interaction for NRP and NO2 . Our results suggest that periconceptional FA intake may reduce ASD risk in those with high prenatal air pollution exposure. Further study is needed to replicate these findings in larger sample sizes and to understand mechanisms of this potential relationship.. Autism Res 2017. (c) 2017 International Society for Autism Research, Wiley Periodicals, Inc. LAY SUMMARY: We examined interactions between periconceptional folic acid (FA) and air pollution exposure on risk of ASD. Mothers exposed to higher levels of air pollution during the first trimester of pregnancy and who reported low supplemental FA intake during the first pregnancy month were at a higher ASD risk compared to mothers exposed to lower levels of air pollution and who reported high first month FA intake. Our results suggest that periconceptional FA intake may reduce ASD risk in those with high prenatal air pollution exposure. Lien vers le texte intégral (Open Access ou abonnement)
6. Gurney ME, Cogram P, Deacon RM, Rex C, Tranfaglia M. {{Multiple Behavior Phenotypes of the Fragile-X Syndrome Mouse Model Respond to Chronic Inhibition of Phosphodiesterase-4D (PDE4D)}}. {Sci Rep}. 2017; 7(1): 14653.
Fragile-X syndrome (FXS) patients display intellectual disability and autism spectrum disorder due to silencing of the X-linked, fragile-X mental retardation-1 (FMR1) gene. Dysregulation of cAMP metabolism is a consistent finding in patients and in the mouse and fly FXS models. We therefore explored if BPN14770, a prototypic phosphodiesterase-4D negative allosteric modulator (PDE4D-NAM) in early human clinical trials, might provide therapeutic benefit in the mouse FXS model. Daily treatment of adult male fmr1 C57Bl6 knock-out mice with BPN14770 for 14 days reduced hyperarousal, improved social interaction, and improved natural behaviors such as nesting and marble burying as well as dendritic spine morphology. There was no decrement in behavioral scores in control C57Bl6 treated with BPN14770. The behavioral benefit of BPN14770 persisted two weeks after washout of the drug. Thus, BPN14770 may be useful for the treatment of fragile-X syndrome and other disorders with decreased cAMP signaling.
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7. Hu Y, Chen Z, Huang L, Xi Y, Li B, Wang H, Yan J, Lee TMC, Tao Q, So KF, Ren C. {{A translational study on looming-evoked defensive response and the underlying subcortical pathway in autism}}. {Sci Rep}. 2017; 7(1): 14755.
Rapidly approaching objects indicating threats can induce defensive response through activating a subcortical pathway comprising superior colliculus (SC), lateral posterior nucleus (LP), and basolateral amygdala (BLA). Abnormal defensive response has been reported in autism, and impaired synaptic connections could be the underlying mechanism. Whether the SC-LP-BLA pathway processes looming stimuli abnormally in autism is not clear. Here, we found that looming-evoked defensive response is impaired in a subgroup of the valproic acid (VPA) mouse model of autism. By combining the conventional neurotracer and transneuronal rabies virus tracing techniques, we demonstrated that synaptic connections in the SC-LP-BLA pathway were abnormal in VPA mice whose looming-evoked defensive responses were absent. Importantly, we further translated the finding to children with autism and observed that they did not present looming-evoked defensive response. Furthermore, the findings of the DTI with the probabilistic tractography showed that the structural connections of SC-pulvinar-amygdala in autism children were weak. The pulvinar is parallel to the LP in a mouse. Because looming-evoked defensive response is innate in humans and emerges much earlier than do social and language functions, the absence of defensive response could be an earlier sign of autism in children.
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8. Ishizuka K, Tabata H, Ito H, Kushima I, Noda M, Yoshimi A, Usami M, Watanabe K, Morikawa M, Uno Y, Okada T, Mori D, Aleksic B, Ozaki N, Nagata KI. {{Possible involvement of a cell adhesion molecule, Migfilin, in brain development and pathogenesis of autism spectrum disorders}}. {J Neurosci Res}. 2017.
Migfilin, encoded by FBLIM1 at the 1p36 locus, is a multi-domain adaptor protein essential for various cellular processes such as cell morphology and migration. Small deletions and duplications at the 1p36 locus, monosomy of which results in neurodevelopmental disorders and multiple congenital anomalies, have also been identified in patients with autism spectrum disorder (ASD). However, the impact of FBLIM1, the gene within 1p36, on the pathogenesis of ASD is unknown. In this study, we performed morphological analyses of migfilin to elucidate its role in brain development. Migfilin was detected specifically in the embryonic and perinatal stages of the mouse brain. Either silencing or overexpression of migfilin in embryos following in utero electroporation disrupted Neocortical neuronal migration. Additionally, neurite elongation was impaired when migfilin was silenced in cultured mouse hippocampal neurons. We then screened FBLIM1 for rare exonic deletions/duplications in 549 Japanese ASD patients and 824 controls, detecting one case of ASD and intellectual delay that harbored a 26-kb deletion at 1p36.21 that solely included the C-terminal exon of FBLIM1. The FBLIM1 mRNA expression level in this case was reduced compared to levels in individuals without FBLIM1 deletion. Our findings indicate that tightly regulated expression of migfilin is essential for neuronal development and that FBLIM1 disruption may be related to the phenotypes associated with ASD and related neurodevelopmental disorders.
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9. Jongsma K, Spaeth E, Schicktanz S. {{Epistemic injustice in dementia and autism patient organizations – an empirical analysis}}. {AJOB Empir Bioeth}. 2017: 0.
Patient organizations (POs) represent patient collectives in health care policy. The inclusion of people with a ‘neuro-psychiatric’ condition poses a particular challenge for the organizational processes and political representation of such collectives. In recent years, new POs (POs of) have been established in the field of autism spectrum disorder and dementia that advocate a different agenda and have a different organizational structure than traditional POs (POs for). The divide between these two types of POs indicates a different standpoint with regard to who should be included on an organizational level, which voices are accepted and who should represent these voices on the political level. The inclusion and exclusion of voices needs to be normatively justified in order to be regarded legitimate representation of such a collective. With the help of Miranda Fricker’s theory of epistemic injustice, we scrutinize whether and, if so, which types of epistemic injustices (wrongdoings to a person as a knower) can be found within POs’ practices and the political field in which they operate, by analyzing 37 interviews with PO representatives, their members and policy makers. Our in-depth analysis indicates that persistent stereotypes hamper the inclusion of affected members both within POs and on the health political level. Being affected causes distrust in having the ‘capacity to know’ in a two-fold way; it is assumed that those who can represent themselves are « not affected enough » to present valuable insights into the condition and those who have difficulties to express themselves due to their condition are excluded because of their affectedness. We conclude that our analysis of the epistemic practices of POs serves as a good starting point to address these shortcomings from a theoretical and practical perspective and offers a valuable starting point for bioethics to understand unjust structures in the health political context.
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10. Kelly B, Williams S, Collins S, Mushtaq F, Mon-Williams M, Wright B, Mason D, Wright J. {{The association between socioeconomic status and autism diagnosis in the United Kingdom for children aged 5-8 years of age: Findings from the Born in Bradford cohort}}. {Autism}. 2017: 1362361317733182.
There has been recent interest in the relationship between socioeconomic status and the diagnosis of autism in children. Studies in the United States have found lower rates of autism diagnosis associated with lower socioeconomic status, while studies in other countries report no association, or the opposite. This article aims to contribute to the understanding of this relationship in the United Kingdom. Using data from the Born in Bradford cohort, comprising 13,857 children born between 2007 and 2011, it was found that children of mothers educated to A-level or above had twice the rate of autism diagnosis, 1.5% of children (95% confidence interval: 1.1%, 1.9%) compared to children of mothers with lower levels of education status 0.7% (95% confidence interval: 0.5%, 0.9%). No statistically significant relationship between income status or neighbourhood material deprivation was found after controlling for mothers education status. The results suggest a substantial level of underdiagnosis for children of lower education status mothers, though further research is required to determine the extent to which this is replicated across the United Kingdom. Tackling inequalities in autism diagnosis will require action, which could include increased education, awareness, further exploration of the usefulness of screening programmes and the provision of more accessible support services.
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11. Kidd SA, Raspa M, Clark R, Usrey-Roos H, Wheeler AC, Liu JA, Wylie A, Sherman SL. {{Attendance at Fragile X Specialty Clinics: Facilitators and Barriers}}. {Am J Intellect Dev Disabil}. 2017; 122(6): 457-75.
The objectives were to describe the demographic characteristics of children with Fragile X syndrome (FXS) and to determine predictors of attendance at Fragile X (FX) clinics. Findings from the Community Support Network (CSN) and Our Fragile X World (OFXW) samples showed that children who attended FX Clinics were mostly male, high-school aged or younger, and white, non-Hispanic. Using logistic regression models, awareness about FX Clinic services, guardian education, and income (CSN), and child age, family income, and total number of co-occurring conditions (OFXW) were predictors of clinic attendance. Demographic and child characteristics accounted for a large portion of the explained variance. Importantly, symptom severity and parent knowledge about services were independent predictors beyond the demographic characteristics of families.
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12. Lukito S, Jones CRG, Pickles A, Baird G, Happe F, Charman T, Simonoff E. {{Specificity of executive function and theory of mind performance in relation to attention-deficit/hyperactivity symptoms in autism spectrum disorders}}. {Mol Autism}. 2017; 8: 60.
Background: Individuals with autism spectrum disorder (ASD) frequently demonstrate symptoms of attention-deficit/hyperactivity disorder (ADHD). Previous findings in children with ASD have suggested that these symptoms are associated with an impairment in executive function (EF) abilities. However, studies rarely considered this association within a single framework that controls for other related factors such as Theory of Mind (ToM) abilities and ASD symptoms. Methods: We used structural equation modeling to explore the relations among EF, ToM, and symptoms of ASD and ADHD, using data from a population-based sample of 100 adolescents with ASD and full-scale IQ >/= 50 (the Special Needs and Autism Project (SNAP) cohort). The study used a multi-measure and multi-informant approach, where performance of inhibition, planning, switching, and working memory tasks indexed EF and performance on tasks involving mentalizing indexed ToM. Measures of ASD and ADHD symptoms included parent and teacher reports and direct observation of the children. Shared source of symptom reporting was accounted for with a parental rating latent factor indexed by symptom measures reported by parents. Results: Impairments in EF abilities were specifically associated with ADHD symptoms while impaired ToM was specifically associated with ASD symptoms, when accounting for the associations of each cognitive domain with the other factors. ASD and ADHD symptom latent factors were also correlated, but this association became nonsignificant once the shared source of reporting from parents was accounted for and within a model that also controlled for the correlated pathway between EF and ToM factors. The specific relations between the cognitive domains and behavioral symptoms remained even after controlling for IQ. Conclusions: In this ASD sample, symptoms of ADHD and ASD are underpinned by separate cognitive domains. The association between EF and ToM impairments is a likely partial explanation for the co-occurrence of ADHD symptoms in ASD, but the role of shared reporting effects is also important and supports the inclusion of independent informants and objective measures in future research.
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13. Mandy W, Clarke K, McKenner M, Strydom A, Crabtree J, Lai MC, Allison C, Baron-Cohen S, Skuse D. {{Assessing Autism in Adults: An Evaluation of the Developmental, Dimensional and Diagnostic Interview-Adult Version (3Di-Adult)}}. {J Autism Dev Disord}. 2017.
We developed a brief, informant-report interview for assessing autism spectrum conditions (ASC) in adults, called the Developmental, Dimensional and Diagnostic Interview-Adult Version (3Di-Adult); and completed a preliminary evaluation. Informant reports were collected for participants with ASC (n = 39), a non-clinical comparison group (n = 29) and a clinical comparison group (n = 20) who had non-autistic mental health conditions. Mean administration time was 38 min (50 min for ASC). Internal consistency (alphas >/= 0.93) and inter-rater agreement (ICCs >/= 0.99) were high. When discriminating ASC from non-ASC, the 3Di-Adult showed excellent sensitivity (95%) and specificity (92%). The 3Di-Adult shows promise as a psychometrically sound and time-efficient interview for collecting standardised informant reports for DSM-5 assessments of ASC in adults, in research and clinical practice.
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14. Ni HC, Lin HY, Tseng WI, Chiu YN, Wu YY, Tsai WC, Gau SS. {{Neural correlates of impaired self-regulation in male youths with autism spectrum disorder: A voxel-based morphometry study}}. {Prog Neuropsychopharmacol Biol Psychiatry}. 2017.
Although recent studies revealed impaired self-regulation (dysregulation) in autism spectrum disorder (ASD), neural correlates of dysregulation and its impacts on autistic neuroanatomy remain unclear. Voxel-based morphometry was applied on structural MRI images in 81 ASD and 61 typically developing (TD) boys aged 7-17years. Dysregulation was defined by the sum of T-scores of Attention, Aggression, and Anxiety/Depression subscales in the Child Behavior Checklist>180. There were 53 and 28 boys in the ASD+Dysregulation and ASD-Dysregulation groups, respectively. First, we compared regional gray matter (GM) volume for ASD and TD. Second, we investigated regional GM volumetric differences among the ASD+Dysregulation, ASD-Dysregulation and TD groups. Lastly, shared and distinct neurostructural correlates of dysregulation were investigated in the ASD and TD groups. The ASD-TD difference on neuroanatomy no longer existed after controlling the dysregulation severity. ASD+Dysregulation had larger regional GM volumes in the right fusiform gyrus, and smaller GM volumes in the anterior prefrontal cortex than ASD-Dysregulation and TD, respectively. ASD+Dysregulation had smaller GM volumes in the left lateral occipital/superior parietal cortex than TD boys. No GM difference was identified between ASD-Dysregulation and TD. ASD and TD had a shared association between GM volumes in the orbitofrontal cortex and dysregulation levels. Our findings suggest that atypical neuroanatomy associated with ASD might partially reflect a disproportionate level of impaired self-regulation. Categorical and dimensional considerations of dysregulation should be implemented in future ASD studies.
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15. Nordahl-Hansen A. {{Atypical: a typical portrayal of autism?}}. {Lancet Psychiatry}. 2017; 4(11): 837-8.
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16. Ptomey LT, Willis EA, Greene JL, Danon JC, Chumley TK, Washburn RA, Donnelly JE. {{The Feasibility of Group Video Conferencing for Promotion of Physical Activity in Adolescents With Intellectual and Developmental Disabilities}}. {Am J Intellect Dev Disabil}. 2017; 122(6): 525-38.
Physical activity (PA) rates of adolescents with intellectual and developmental disabilities (IDD) are low and effective strategies for increasing PA are limited. The purpose of this study was to assess the feasibility of a group-based PA intervention that was delivered remotely to adolescents with IDD. Participants attended 30-min group PA sessions 3 times a week. PA sessions were delivered in their homes by video conferencing on a tablet computer. Thirty-one participants enrolled and 29 completed the 12-week intervention. Participants attended 77.2% +/- 20.8% of scheduled sessions and averaged 26.7 +/- 2.8 min of PA/session, with 11.8 +/- 4.8 min at moderate- to vigorous intensity. Group-based PA delivered remotely may be a feasible approach for the promotion of PA in adolescents with IDD.
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17. Pyronneau A, He Q, Hwang JY, Porch M, Contractor A, Zukin RS. {{Aberrant Rac1-cofilin signaling mediates defects in dendritic spines, synaptic function, and sensory perception in fragile X syndrome}}. {Sci Signal}. 2017; 10(504).
Fragile X syndrome (FXS) is the most common inherited cause of intellectual disabilities and a leading cause of autism. FXS is caused by a trinucleotide expansion in the gene FMR1 on the X chromosome. The neuroanatomical hallmark of FXS is an overabundance of immature dendritic spines, a factor thought to underlie synaptic dysfunction and impaired cognition. We showed that aberrantly increased activity of the Rho GTPase Rac1 inhibited the actin-depolymerizing factor cofilin, a major determinant of dendritic spine structure, and caused disease-associated spine abnormalities in the somatosensory cortex of FXS model mice. Increased cofilin phosphorylation and actin polymerization coincided with abnormal dendritic spines and impaired synaptic maturation. Viral delivery of a constitutively active cofilin mutant (cofilinS3A) into the somatosensory cortex of Fmr1-deficient mice rescued the immature dendritic spine phenotype and increased spine density. Inhibition of the Rac1 effector PAK1 with a small-molecule inhibitor rescued cofilin signaling in FXS mice, indicating a causal relationship between PAK1 and cofilin signaling. PAK1 inhibition rescued synaptic signaling (specifically the synaptic ratio of NMDA/AMPA in layer V pyramidal neurons) and improved sensory processing in FXS mice. These findings suggest a causal relationship between increased Rac1-cofilin signaling, synaptic defects, and impaired sensory processing in FXS and uncover a previously unappreciated role for impaired Rac1-cofilin signaling in the aberrant spine morphology and spine density associated with FXS.
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18. Robinson S, Hastings RP, Weiss JA, Pagavathsing J, Lunsky Y. {{Self-compassion and psychological distress in parents of young people and adults with intellectual and developmental disabilities}}. {J Appl Res Intellect Disabil}. 2017.
BACKGROUND: Parenting an individual with intellectual and developmental disabilities (IDD) can be challenging, particularly during adulthood. It is important to better understand ways of supporting families as individuals with IDD age. Self-compassion is a potential internal coping resource for parents, and is strongly linked to positive mental health outcomes, though research has yet to examine it in parents of adults with IDD. METHOD: The current study examines the association between self-compassion and measures of well-being for 56 parents of adults with IDD. RESULTS: Greater self-compassion was related to lower levels of stress and depression, even after accounting for other known stressors, such as economic disadvantage, having a child with an Autism Spectrum Disorder diagnosis, and high parent burden. CONCLUSIONS: Self-compassion may offer resiliency against these parenting challenges.
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19. Santini E, Huynh TN, Longo F, Koo SY, Mojica E, D’Andrea L, Bagni C, Klann E. {{Reducing eIF4E-eIF4G interactions restores the balance between protein synthesis and actin dynamics in fragile X syndrome model mice}}. {Sci Signal}. 2017; 10(504).
Fragile X syndrome (FXS) is the most common form of inherited intellectual disability and autism spectrum disorder. FXS is caused by silencing of the FMR1 gene, which encodes fragile X mental retardation protein (FMRP), an mRNA-binding protein that represses the translation of its target mRNAs. One mechanism by which FMRP represses translation is through its association with cytoplasmic FMRP-interacting protein 1 (CYFIP1), which subsequently sequesters and inhibits eukaryotic initiation factor 4E (eIF4E). CYFIP1 shuttles between the FMRP-eIF4E complex and the Rac1-Wave regulatory complex, thereby connecting translational regulation to actin dynamics and dendritic spine morphology, which are dysregulated in FXS model mice that lack FMRP. Treating FXS mice with 4EGI-1, which blocks interactions between eIF4E and eIF4G, a critical interaction partner for translational initiation, reversed defects in hippocampus-dependent memory and spine morphology. We also found that 4EGI-1 normalized the phenotypes of enhanced metabotropic glutamate receptor (mGluR)-mediated long-term depression (LTD), enhanced Rac1-p21-activated kinase (PAK)-cofilin signaling, altered actin dynamics, and dysregulated CYFIP1/eIF4E and CYFIP1/Rac1 interactions in FXS mice. Our findings are consistent with the idea that an imbalance in protein synthesis and actin dynamics contributes to pathophysiology in FXS mice, and suggest that targeting eIF4E may be a strategy for treating FXS.
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20. Silva K, Lima M, Santos-Magalhaes A, Fafiaes C, de Sousa L. {{Can Dogs Assist Children with Severe Autism Spectrum Disorder in Complying with Challenging Demands? An Exploratory Experiment with a Live and a Robotic Dog}}. {J Altern Complement Med}. 2017.
OBJECTIVES: Prompted by the need to find effective ways to enhance compliance in children with autism spectrum disorder (ASD), and building on the increasing interest in dog-assisted interventions for this population, this study provides an exploratory test on whether dogs may assist children with severe ASD in complying with challenging demands while also decreasing behavioral and cardiovascular distress. DESIGN: A within-subject design was used. Depending on condition, participants were allowed to engage with a particular stimulus-their preferred toy, a live dog, or a robotic dog-before being exposed to a demanding task in which they had to wait for permission to eat a desired food item (« prohibition task »). Although inactive, the stimulus remained present during the prohibition task. SUBJECTS AND SETTINGS: Ten male children, aged between 6 and 9 years and diagnosed with severe ASD, participated in this study. All were clinically referred as having serious compliance difficulties in everyday routines. Testing occurred at participants’ homes. OUTCOME MEASURES: Participants’ emotional expressions, latency to distress, compliance levels, and behaviors that were shown during committed compliance were assessed during the prohibition task. In addition, cardiovascular reactivity to the task was monitored. RESULTS: Obtained data revealed significant differences between conditions for some of the considered measures. Latency to distress was higher in the live dog than in the toy condition. Committed compliance was higher in the live dog than in the toy and robot conditions. Quiet waiting during committed compliance was higher in the live dog condition than in the toy condition, and tension release behaviors were lower. In addition, heart rate reactivity was lower in the live dog condition than in the toy condition. CONCLUSIONS: The live dog condition appeared to have a calming effect on the participants, hypothetically facilitating compliance. Although promising, these findings are only preliminary and their clinical significance needs to be assessed in future studies.
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21. Strasser L, Downes M, Kung J, Cross JH, De Haan M. {{Prevalence and risk factors for autism spectrum disorder in epilepsy: a systematic review and meta-analysis}}. {Dev Med Child Neurol}. 2017.
AIM: To assess the prevalence and risk factors for autism spectrum disorder (ASD) in epilepsy, and to better understand the relationship and comorbidity between these disorders. METHOD: PsychINFO and PubMed were searched for articles published in the past 15 years that examined the prevalence of ASD in individuals with epilepsy. RESULTS: A total of 19 studies were found with a pooled ASD prevalence of 6.3% in epilepsy. When divided by type, the risks of ASD for general epilepsy, infantile spasms, focal seizures, and Dravet syndrome were 4.7%, 19.9%, 41.9%, and 47.4% respectively. Studies with populations under 18 years showed a 13.2 times greater risk of ASD than study populations over 18 years, and samples with most (>50%) individuals with intellectual disability showed a greater risk 4.9 times higher than study populations with a minority of individuals with intellectual disability. The main risk factors for ASD reported in the 19 studies included presence of intellectual disability, sex, age, and symptomatic aetiology of epilepsy. INTERPRETATION: Current research supports a high prevalence of ASD in epilepsy. This study helps to define the clinical profile of patients with epilepsy who are at risk for ASD, which may help clinicians in early screening and diagnosis of ASD in this population. WHAT THIS PAPER ADDS: Critical evaluation of previous studies examining the prevalence of autism spectrum disorder (ASD) in individuals with epilepsy. A meta-analysis of 19 studies showed a pooled ASD prevalence of 6.3% in individuals with epilepsy. Studies that included a majority of individuals with intellectual disability or younger population age had a higher prevalence of autism. Risk factors reported in studies included presence of intellectual disability, sex, age, and symptomatic epilepsy origin.
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22. Woodbury-Smith M, Deneault E, Yuen RKC, Walker S, Zarrei M, Pellecchia G, Howe JL, Hoang N, Uddin M, Marshall CR, Chrysler C, Thompson A, Szatmari P, Scherer SW. {{Mutations in RAB39B in individuals with intellectual disability, autism spectrum disorder, and macrocephaly}}. {Mol Autism}. 2017; 8: 59.
Background: Autism spectrum disorder (ASD), a developmental disorder of early childhood onset, affects males four times more frequently than females, suggesting a role for the sex chromosomes. In this study, we describe a family with ASD in which a predicted pathogenic nonsense mutation in the X-chromosome gene RAB39B segregates with ASD phenotype. Methods: Clinical phenotyping, microarray, and whole genome sequencing (WGS) were performed on the five members of this family. Maternal and female sibling X inactivation ratio was calculated, and phase was investigated. Mutant-induced pluripotent stem cells engineered for an exon 2 nonsense mutation were generated and differentiated into cortical neurons for expression and pathway analyses. Results: Two males with an inherited RAB39B mutation both presented with macrocephaly, intellectual disability (ID), and ASD. Their female sibling with the same mutation presented with ID and a broad autism phenotype. In contrast, their transmitting mother has no neurodevelopmental diagnosis. Our investigation of phase indicated maternal preferential inactivation of the mutated allele, with no such bias observed in the female sibling. We offer the explanation that this bias in X inactivation may explain the absence of a neurocognitive phenotype in the mother. Our cellular knockout model of RAB39B revealed an impact on expression in differentiated neurons for several genes implicated in brain development and function, supported by our pathway enrichment analysis. Conclusions: Penetrance for ASD is high among males but more variable among females with RAB39B mutations. A critical role for this gene in brain development and function is demonstrated.
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23. Yamasaki T, Maekawa T, Fujita T, Tobimatsu S. {{Connectopathy in Autism Spectrum Disorders: A Review of Evidence from Visual Evoked Potentials and Diffusion Magnetic Resonance Imaging}}. {Front Neurosci}. 2017; 11: 627.
Individuals with autism spectrum disorder (ASD) show superior performance in processing fine details; however, they often exhibit impairments of gestalt face, global motion perception, and visual attention as well as core social deficits. Increasing evidence has suggested that social deficits in ASD arise from abnormal functional and structural connectivities between and within distributed cortical networks that are recruited during social information processing. Because the human visual system is characterized by a set of parallel, hierarchical, multistage network systems, we hypothesized that the altered connectivity of visual networks contributes to social cognition impairment in ASD. In the present review, we focused on studies of altered connectivity of visual and attention networks in ASD using visual evoked potentials (VEPs), event-related potentials (ERPs), and diffusion tensor imaging (DTI). A series of VEP, ERP, and DTI studies conducted in our laboratory have demonstrated complex alterations (impairment and enhancement) of visual and attention networks in ASD. Recent data have suggested that the atypical visual perception observed in ASD is caused by altered connectivity within parallel visual pathways and attention networks, thereby contributing to the impaired social communication observed in ASD. Therefore, we conclude that the underlying pathophysiological mechanism of ASD constitutes a « connectopathy. »
