Pubmed du 24/01/18

Pubmed du jour

2018-01-24 12:03:50

1. Angeard N, Huerta E, Jacquette A, Cohen D, Xavier J, Gargiulo M, Servais L, Eymard B, Heron D. {{Childhood-onset form of myotonic dystrophy type 1 and autism spectrum disorder: Is there comorbidity?}}. {Neuromuscular disorders : NMD}. 2017.

Myotonic dystrophy type 1 (DM1) is a multisystemic disorder with neuromuscular symptoms and brain dysfunctions. Depending on the phenotypic expression, the degree of cognitive impairment remains heterogeneous, ranging from moderate to severe intellectual disability in the congenital form, to executive, visuospatial and personality dysfunction in the adult-onset form. Studies exploring the cognitive or psychiatric impairments in the childhood form of DM1, characterized by an age of onset between one and ten years, uneventful pre and post natal history and normal development the first year of life, are scarce and show conflicting results in regard to a comorbid diagnosis of Autism Spectrum Disorder (ASD). The aim of the current review is to summarize diagnostic criteria and update the state of the debate regarding comorbidity. Evidence from 9 studies collected in PubMed database (representing a total of 175 cases) focusing on clinical, neuropsychological and neuroimaging domains in childhood DM1 is considered and similarities or differences between childhood DM1 and ASD are identified. Highlighting what is known about the neurocognitive features specific to the childhood-onset form of DM1 could help (1) propose early screening regarding socio-emotional and attentional/executive functions or (2) implement therapeutic programs based on reinforcement of executive skills or social cognition.

Lien vers le texte intégral (Open Access ou abonnement)

2. Bobylova MY, Ivanova IV, Nekrasova IV, Pylaeva OA, Mukhin KY, Kholin AA, Iljina ES, Kulikov AV, Iljina ES, Nesterovsky YE. {{[The course and the development of epilepsy in patients with typical variant of Rett syndrome and mutations]}}. {Zh Nevrol Psikhiatr Im S S Korsakova}. 2017; 117(11. Vyp. 2): 54-61.

AIM: Studying data of anamnesis, clinical state, electro-encephalographic, brain MRI in patients with Rett syndrome (capital EM, Cyrilliccapital IE, Cyrilliccapital ES, Cyrilliccapital ER, Cyrillic2). MATERIAL AND METHODS: We studied 11 patients (female) from three to 23 years old with Rett syndrome and MeCP2 mutations. Observation continued 10 years (2006-2015). We analyzed the results of the neurological status, night sleep video-EEG monitoring, MRI. RESULTS AND CONCLUSION: Epilepsy diagnosed in six cases (54, 5%). The overage age of debut of epileptic seizures was 3 years 9 months. There are some types of seizures: generalized, myoclonic, myotonic, tonic, versive, focal motor, atypical absences. Status epilepticus evolved in one patient. Generalized seizures were 56, 25%, focal seizures – 43, 75%. EEG changing marked in nine patients (81, 8%): slowdown back activity, episodes of periodic regional slowdown, regional epileptiform activity, and diffuse epileptiform activity like benign focal epileptiform discharges (BFED). five patients took antiepileptic drugs. All of them had improved during treatment. There were reducing of frequency of the seizures up 50% – 4 cases (80%). one patients with resistant epilepsy was taken combination of drugs (levetirecetam, topiromat, zonisamide, benzodiazepine) with stopping of seizures in the night sleep and decreasing of frequency of daytime seizures to 50%. We believe there is very important of study epilepsy in patients with Rett syndrome and improvement of its treatment.

Lien vers le texte intégral (Open Access ou abonnement)

3. Brodhead MT, Courtney WT, Thaxton JR. {{Using activity schedules to promote varied application use in children with autism}}. {Journal of applied behavior analysis}. 2018; 51(1): 80-6.

We evaluated the effects of an activity schedule embedded within an iPad on varied play across applications. After establishing a pattern of repetitive gameplay, we taught three children with autism to follow the activity schedule using physical guidance. All participants increased their varied play to four applications per session and demonstrated independent and accurate activity schedule usage. The activity schedule was removed, and responding decreased to baseline levels, demonstrating the activity schedule’s control over varied responding. The activity schedule was reintroduced and participant responding maintained when engaging with novel applications.

Lien vers le texte intégral (Open Access ou abonnement)

4. Cassidy SA, Bradley L, Bowen E, Wigham S, Rodgers J. {{Measurement properties of tools used to assess depression in adults with and without autism spectrum conditions: A systematic review}}. {Autism Res}. 2018.

Depression is the most commonly experienced mental health condition in adults with autism spectrum conditions (ASC). However, it is unclear what tools are currently being used to assess depression in ASC, or whether tools need to be adapted for this group. This systematic review therefore aimed to identify tools used to assess depression in adults with and without ASC, and then evaluate these tools for their appropriateness and measurement properties. Medline, PsychINFO and Web of Knowledge were searched for studies of depression in: (a) adults with ASC, without co-morbid intellectual disability; and (b) adults from the general population without co-morbid conditions. Articles examining the measurement properties of these tools were then searched for using a methodological filter in PubMed, and the quality of the evidence was evaluated using the COSMIN checklist. Twelve articles were identified which utilized three tools to assess depression in adults with ASC, but only one article which assessed the measurement properties of one of these tools was identified and thus evaluated. Sixty-four articles were identified which utilized five tools to assess depression in general population adults, and fourteen articles had assessed the measurement properties of these tools. Overall, two tools were found to be robust in their measurement properties in the general population-the Beck Depression Inventory (BDI-II), and the patient health questionnaire (PHQ-9). Crucially only one study was identified from the COSMIN search, which showed weak evidence in support of the measurement properties of the BDI-II in an ASC sample. Implications for effective measurement of depression in ASC are discussed. Autism Res 2018. (c) 2018 The Authors Autism Research published by International Society for Autism Research and Wiley Periodicals, Inc. LAY SUMMARY: Depression is the most common mental health problem experienced by adults with autism. However, the current study found very limited evidence regarding how useful tools developed for the general population are for adults with autism. We therefore suggest how these tools could be adapted to more effectively assess depression in adults with autism, and improve these individuals access to mental health assessment and support.

Lien vers le texte intégral (Open Access ou abonnement)

5. Castillo MI, Clark DR, Schaller EA, Donaldson JM, DeLeon IG, Kahng S. {{Descriptive assessment of problem behavior during transitions of children with intellectual and developmental disabilities}}. {Journal of applied behavior analysis}. 2018; 51(1): 99-117.

Transitions from one activity to another may evoke problem behavior from individuals with intellectual disabilities. One explanation for the occurrence of problem behavior could be the change in relative densities of reinforcement between the two activities. We conducted a descriptive assessment of problem behavior with four children during transitions to and from several different contexts. We observed that, in most cases, the probability of problem behavior was greater during a transition to an activity with a lower density of reinforcement than during a transition to an activity with a higher density of reinforcement. We discuss our findings in terms of problem behavior associated with transitions in activities with different reinforcer densities, as well as the possibility that the problem behavior may be associated with shifts in motivating operations.

Lien vers le texte intégral (Open Access ou abonnement)

6. Chen YN, Du HY, Shi ZY, He L, He YY, Wang D. {{Serum proteomic profiling for autism using magnetic bead-assisted matrix-assisted laser desorption ionization time-of-flight mass spectrometry: a pilot study}}. {World journal of pediatrics : WJP}. 2018.

BACKGROUND: The pathogenesis of autism spectrum disorders remains elusive and currently there are no diagnostic or predictive biomarkers in autism available. Proteomic profiling has been used in a wide range of neurodevelopmental disorder studies, which could produce deeper perceptions of the molecular bases behind certain disease and potentially becomes useful in discovering biomarkers in autism spectrum disorders. METHODS: Serum samples were collected from autistic children about 3 years old in age (n = 32) and healthy controls (n = 20) in similar age and gender. The samples were identified specific proteins that are differentially expressed by magnetic bead-based pre-fractionation and matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-ToF-MS). RESULTS: Eight protein peaks were significantly different in autistic children from the healthy controls (P < 0.0001). The two peaks with the most significant differences were 6428 and 7758 Da in size. CONCLUSION: According to differences in serum protein profiles between the autistic children and healthy controls, this study identified a set of differentially expressed proteins those are significant for further evaluation and might function as biomarkers in autism. Lien vers le texte intégral (Open Access ou abonnement)

7. Dachew BA, Mamun A, Maravilla JC, Alati R. {{Pre-eclampsia and the risk of autism-spectrum disorder in offspring: meta-analysis}}. {The British journal of psychiatry : the journal of mental science}. 2018; 212(3): 142-7.

BACKGROUND: Evidence about the effect of intrauterine exposure to pre-eclampsia on offspring autism-spectrum disorder (ASD) is not well established. Aims To examine the association between pre-eclampsia and ASD. METHOD: PubMed, Embase and PsycINFO databases were searched. Pooled relative risks (RR) with 95% confidence intervals were calculated. Subgroup and sensitivity analyses were performed. Heterogeneity was assessed using Cochran’s Q- and the I 2-test. The presence of publication bias was evaluated by Egger’s test and visual inspection of the symmetry in funnel plots. RESULTS: Ten studies meet the inclusion criteria. The risk of ASD was 32% higher in offspring who had intrauterine exposure to pre-eclampsia compared with those not exposed (RR = 1.32, 95% CI 1.20-1.45). Sensitivity analysis revealed consistent pooled estimates ranging from RR = 1.30 (95% CI 1.17-1.44) to RR = 1.37 (95% CI 1.26-1.48). We found no significant heterogeneity and evidence of publication bias. CONCLUSION: Pre-eclampsia increased the risk of ASD in offspring. The finding suggests a need for early screening for ASD in offspring of women with pre-eclampsia. Declaration of interest None.

Lien vers le texte intégral (Open Access ou abonnement)

8. Eggleston JD, Landers MR, Bates BT, Nagelhout E, Dufek JS. {{Examination of gait parameters during perturbed over-ground walking in children with autism spectrum disorder}}. {Res Dev Disabil}. 2018; 74: 50-6.

BACKGROUND: Many children with Autism Spectrum Disorder (ASD) are school-aged and typically carry a backpack. It is important to understand how this task affects walking. Weighted vests (WVs) often prescribed to mitigate behavioral effects of ASD. The effects of backpack and WV walking have not been examined in children with ASD. AIMS: To quantify differences in lower extremity mechanics in children with ASD during WV and backpack walking. METHODS: Eight male participants completed 15 trials in three conditions: body mass, and carrying or wearing a backpack or WV with 15% added body mass. Three-dimensional kinematic data were collected and normalized to 100% of the gait cycle. The Model Statistic was utilized to test for bilateral asymmetries between the lower extremity joints at all points along the gait cycle. RESULTS: Analysis revealed similar numbers of significant asymmetries in hip (71.0, 70.4, 60.6), knee (68.4, 71.5, 74.6), and ankle (64.1, 68.9, 68.4) for unloaded, backpack, and WV, respectively. CONCLUSION: Participants exhibited individualized kinematic symmetry-responses to the loaded conditions compared to the unloaded condition. These findings suggest that 15% body mass backpack or WV does not affect gait symmetry in children with ASD.

Lien vers le texte intégral (Open Access ou abonnement)

9. Falck-Ytter T, Nystrom P, Gredeback G, Gliga T, Bolte S. {{Reduced orienting to audiovisual synchrony in infancy predicts autism diagnosis at 3 years of age}}. {J Child Psychol Psychiatry}. 2018.

BACKGROUND: Effective multisensory processing develops in infancy and is thought to be important for the perception of unified and multimodal objects and events. Previous research suggests impaired multisensory processing in autism, but its role in the early development of the disorder is yet uncertain. Here, using a prospective longitudinal design, we tested whether reduced visual attention to audiovisual synchrony is an infant marker of later-emerging autism diagnosis. METHODS: We studied 10-month-old siblings of children with autism using an eye tracking task previously used in studies of preschoolers. The task assessed the effect of manipulations of audiovisual synchrony on viewing patterns while the infants were observing point light displays of biological motion. We analyzed the gaze data recorded in infancy according to diagnostic status at 3 years of age (DSM-5). RESULTS: Ten-month-old infants who later received an autism diagnosis did not orient to audiovisual synchrony expressed within biological motion. In contrast, both infants at low-risk and high-risk siblings without autism at follow-up had a strong preference for this type of information. No group differences were observed in terms of orienting to upright biological motion. CONCLUSIONS: This study suggests that reduced orienting to audiovisual synchrony within biological motion is an early sign of autism. The findings support the view that poor multisensory processing could be an important antecedent marker of this neurodevelopmental condition.

Lien vers le texte intégral (Open Access ou abonnement)

10. Handen BL, Mazefsky CA, Gabriels RL, Pedersen KA, Wallace M, Siegel M. {{Risk Factors for Self-injurious Behavior in an Inpatient Psychiatric Sample of Children with Autism Spectrum Disorder: A Naturalistic Observation Study}}. {J Autism Dev Disord}. 2018.

Limited information about self-injurious behavior (SIB) is known for children and adolescents with Autism Spectrum Disorder (ASD) who require intensive behavioral health interventions. We examined risk-factors for SIB in 302 individuals with ASD (ages 4-20) admitted to six specialized psychiatric inpatient units. Seventy-four percent were reported by a caregiver to display SIB, however, only 25% were observed to engage in daily SIB during hospitalization. Those exhibiting SIB across environments had significantly higher ratings on caregiver questionnaires of SIB severity. Tree-structured classification was used to develop and validate two predictive models, one indicating which inpatient youth with ASD are likely to have SIB and a second indicating which individuals with SIB at home are likely to continue in an inpatient setting.

Lien vers le texte intégral (Open Access ou abonnement)

11. Hong ER, Neely L, Gerow S, Gann C. {{The effect of caregiver-delivered social-communication interventions on skill generalization and maintenance in ASD}}. {Res Dev Disabil}. 2018; 74: 57-71.

BACKGROUND: Although caregiver-delivered social communication interventions have been considered scientifically proven practices for individuals with autism spectrum disorders, it is not well examined if these types of intervention modes are truly effective in promoting skill generalization and maintenance within those individuals with autism spectrum disorders. AIMS: The purpose of this meta-analysis was to evaluate the status of the extant literature regarding the measures on generalization and/or maintenance of effects of caregiver-delivered communication interventions for children with autism spectrum disorders. METHODS AND PROCEDURES: This systematic literature review and meta-analysis evaluated peer-reviewed research regarding the effects of caregiver-implemented interventions on the maintenance and generalization of the social-communication skills for children with autism spectrum disorders. A total of 34 articles were included following a systematic search. Articles were summarized according to the following categories: (a) generalization dimension, (b) generalization assessment design, (c) maintenance assessment design, (d) generalization/maintenance teaching strategy, and (e) latency to maintenance probes. After application of design standards, aggregate Tau-U and non-overlap of pairs effect sizes were calculated with a total of 67 separate contrasts across seven studies. OUTCOMES AND RESULTS: Overall, effect size scores ranged from small to large effects across all comparisons. On average, most of the baseline to maintenance and generalization comparisons produced moderate to large effects. Whereas, small to moderate or even deteriorate effects were found in most of the intervention to maintenance and generalization comparisons. CONCLUSIONS AND IMPLICATIONS: The findings in this review suggest that caregiver-delivered social-communication interventions are likely to result in mixed effects on skill generalization and maintenance within children with autism spectrum disorders. Implications for future research and practice are discussed.

Lien vers le texte intégral (Open Access ou abonnement)

12. Kopec AM, Fiorentino MR, Bilbo SD. {{Gut-immune-brain dysfunction in Autism: Importance of sex}}. {Brain Res}. 2018.

Autism Spectrum Disorder (ASD) is characterized by social behavior deficits, stereotypies, cognitive rigidity, and in some cases severe intellectual impairment and developmental delay. Although ASD is most widely identified by its neurological deficits, gastrointestinal issues are common in ASD. An intimate and complex relationship exists between the gut, the immune system, and the brain, leading to the hypothesis that ASD may be a systems-level disease affecting the gut and immune systems, in addition to the brain. Despite significant advances in understanding the contribution of the gut and immune systems to the etiology of ASD, there is an intriguing commonality among patients that is not well understood: they are predominantly male. Virtually no attention has been given to the potential role of sex-specific regulation of gut, peripheral, and central immune function in ASD, despite the 4:1 male-to-female bias in this disorder. In this review, we discuss recent revelations regarding the impact of gut-immune-brain relationships on social behavior in rodent models and in ASD patients, placing them in the context of known or putative sex specific mechanisms.

Lien vers le texte intégral (Open Access ou abonnement)

13. McCormick CEB, Sheinkopf SJ, Levine TP, LaGasse LL, Tronick E, Lester BL. {{Diminished respiratory sinus arrhythmia response in infants later diagnosed with autism spectrum disorder}}. {Autism Res}. 2018.

Indicators of risk for developing Autism Spectrum Disorder (ASD) are difficult to detect within the first year of life. In this study, infants who were originally followed prospectively to examine general developmental risks due to substance exposure interacted with their mother and an unfamiliar experimenter for 2-min episodes at 4 months of age. Electrocardiogram was collected to measure respiratory sinus arrhythmia (RSA) and the session was video recorded for behavioral coding. Two groups of infants were compared: infants with a diagnosed ASD outcome (N = 8) and matched controls (N = 186). Infants were compared on mean RSA and infant behavioral codes for each 2-min episode. No significant group differences were revealed on RSA or behavior during interactions between the infants and mothers. However, in response to play with a stranger, infants with an ASD outcome had lower RSA (M = 2.49, 95% CI [2.30, 2.98]) than controls (M = 3.12, 95% CI [3.06, 3.18]). During the interaction with a stranger, lower RSA response was associated with more protesting behaviors (P < 0.01), whereas higher RSA response was associated with more social monitoring (P = 0.001). Lower RSA suggests that 4-month-old infants later diagnosed with ASD exhibited poorer autonomic regulation during interaction with an unfamiliar adult than did controls. Physiological regulation during interactions with a new social partner may be disrupted early in infancy in children with ASD, as indicated here by lower RSA, and therefore be a potential target for developing early risk screening tools for ASD. Autism Res 2018. (c) 2018 International Society for Autism Research, Wiley Periodicals, Inc. LAY SUMMARY: Autism Spectrum Disorder (ASD) emerges within the first years of life; however, it is difficult to identify children who will develop autism before 12 months of age based on behavioral measures. In a study of infants who were followed from birth, infants who were later diagnosed with ASD had poorer physiological regulation during play with a new adult. With additional evidence, poorer physiological regulation may function as an early sign of ASD risk. Lien vers le texte intégral (Open Access ou abonnement)

14. Morris SM, Gutmann DH. {{A genotype-phenotype correlation for quantitative autistic trait burden in neurofibromatosis 1}}. {Neurology}. 2018; 90(8): 377-9.

Lien vers le texte intégral (Open Access ou abonnement)

15. Nuttall AK, Coberly B, Diesel SJ. {{Childhood Caregiving Roles, Perceptions of Benefits, and Future Caregiving Intentions Among Typically Developing Adult Siblings of Individuals with Autism Spectrum Disorder}}. {J Autism Dev Disord}. 2018.

Typically developing siblings (TDS) of individuals with Autism Spectrum Disorder (ASD) frequently serve as caregivers during childhood, known as parentification, and primary caregivers for siblings in adulthood. In order to evaluate mechanisms linking these roles, we surveyed emerging-adult TDS (N = 108) about childhood parentification roles caring for parents and siblings, current perceptions of benefits associated with ASD and with engaging in parentification, and intention to provide future caregiving. We hypothesized that parent-focused parentification would negatively impact caregiving intention via perception of decreased benefits whereas sibling-focused parentification would positively impact intention via perception of increased benefits. Results indicate that parent-focused parentification is common and associated with fewer perceived benefits of caregiving and less intention to provide future caregiving. Prevention implications are discussed.

Lien vers le texte intégral (Open Access ou abonnement)

16. Solomon O, Lawlor MC. {{Beyond V40.31: Narrative Phenomenology of Wandering in Autism and Dementia}}. {Culture, medicine and psychiatry}. 2018.

Research on autism spectrum disorder (ASD) and on Alzheimer’s Disease (AD) and other types of dementia describes a behaviour called ‘wandering’, a term that denotes movement through space lacking intention or exact destination, as when a person is disoriented or not self-aware. In the U.S., ‘wandering’ in both ASD and AD has been examined mostly from a management and prevention perspective. It prioritizes safety while primarily overlooking personal experiences of those who ‘wander’ and their families, thus limiting the range of potentially effective strategies to address this issue. Communicative challenges faced by many people diagnosed with ASD and AD further obscure the experiential, existential aspects of ‘wandering’. This article reflects an increasing concern of social science scholars interested in whether and how the conceptual and practical strategies to address ‘wandering’ are informed by the situated experiences of people with cognitive and developmental disabilities and their families. We examine ‘wandering’ at the intersections of personal experience, family life, clinical practice, public health policy, and legislation, as a conceptually rich site where notions of personhood, subjectivity, intentionality, and quality of life powerfully and consequentially converge to impact the lives of many people with ASD and AD, and their families. We draw upon critical autism studies describing how attributions of personhood, subjectivity, intentionality, rational agency, and moral autonomy of people with ASD have been contingent upon the norms and conventions governing movement of the human body through space (Hilton, Afr Am Rev 50(2):221-235, 2017). When this movement is deemed aberrant, the person may be construed as irrational, a danger to self because of a lack of self-awareness, and a danger to others because of a lack of empathy. These attributions put the person at risk of being excluded from the considerations and, more importantly, the obligations of the ‘moral community’ to ensure that he or she has a ‘good human life’ (Barnbaum, The Ethics of Autism: Among Them but not of Them. Indiana University Press, Bloomington, 2008; Silvers and Francis, Metaphilosophy 40(3/4):475-498, 2009). Using ethnographic, narrative phenomenological (Mattingly, The Paradox of Hope: Journeys through a Clinical Borderland. Berkeley: University of California Press, 2010), and medical humanities (Charon, JAMA 286:1897-1902, 2001; Narrative Medicine: Honoring the Stories of Illness. New York: Oxford University Press, 2006) approaches, we examine multiple perspectives on ‘wandering’ in ASD and AD across narrative discourse genres, institutional contexts, and media of representation. We argue for an extension of the prevention and management view to focus not only on safety but also on what phenomenologist Merleau-Ponty (1962) called « having a world » (p. 146). The analysis is intended to inform clinical practice, policy and public health efforts to enhance understanding of first and second person perspectives on ‘wandering’ in order to improve the participation and quality of life of people with ASD and AD who ‘wander’, and their families.

Lien vers le texte intégral (Open Access ou abonnement)

17. Steinmetz AB, Stern SA, Kohtz AS, Descalzi G, Alberini CM. {{Insulin-Like Growth Factor II Targets the mTOR Pathway to Reverse Autism-Like Phenotypes in Mice}}. {J Neurosci}. 2018; 38(4): 1015-29.

Autism spectrum disorder (ASD) is a developmental disability characterized by impairments in social interaction and repetitive behavior, and is also associated with cognitive deficits. There is no current treatment that can ameliorate most of the ASD symptomatology; thus, identifying novel therapies is urgently needed. We used male BTBR T(+)Itpr3(tf) /J (BTBR) mice, a model that reproduces most of the core behavioral phenotypes of ASD, to test the effects of systemic administration of insulin-like growth factor II (IGF-II), a polypeptide that crosses the blood-brain barrier and acts as a cognitive enhancer. We show that systemic IGF-II treatments reverse the typical defects in social interaction, cognitive/executive functions, and repetitive behaviors reflective of ASD-like phenotypes. In BTBR mice, IGF-II, via IGF-II receptor, but not via IGF-I receptor, reverses the abnormal levels of the AMPK-mTOR-S6K pathway and of active translation at synapses. Thus, IGF-II may represent a novel potential therapy for ASD.SIGNIFICANCE STATEMENT Currently, there is no effective treatment for autism spectrum disorder (ASD), a developmental disability affecting a high number of children. Using a mouse model that expresses most of the key core as well as associated behavioral deficits of ASD, that are, social, cognitive, and repetitive behaviors, we report that a systemic administration of the polypeptide insulin-like growth factor II (IGF-II) reverses all these deficits. The effects of IGF-II occur via IGF-II receptors, and not IGF-I receptors, and target both basal and learning-dependent molecular abnormalities found in several ASD mice models, including those of identified genetic mutations. We suggest that IGF-II represents a potential novel therapeutic target for ASD.

Lien vers le texte intégral (Open Access ou abonnement)

18. Talbot ZN, Sparks FT, Dvorak D, Curran BM, Alarcon JM, Fenton AA. {{Normal CA1 Place Fields but Discoordinated Network Discharge in a Fmr1-Null Mouse Model of Fragile X Syndrome}}. {Neuron}. 2018; 97(3): 684-97.e4.

Silence of FMR1 causes loss of fragile X mental retardation protein (FMRP) and dysregulated translation at synapses, resulting in the intellectual disability and autistic symptoms of fragile X syndrome (FXS). Synaptic dysfunction hypotheses for how intellectual disabilities like cognitive inflexibility arise in FXS predict impaired neural coding in the absence of FMRP. We tested the prediction by comparing hippocampus place cells in wild-type and FXS-model mice. Experience-driven CA1 synaptic function and synaptic plasticity changes are excessive in Fmr1-null mice, but CA1 place fields are normal. However, Fmr1-null discharge relationships to local field potential oscillations are abnormally weak, stereotyped, and homogeneous; also, discharge coordination within Fmr1-null place cell networks is weaker and less reliable than wild-type. Rather than disruption of single-cell neural codes, these findings point to invariant tuning of single-cell responses and inadequate discharge coordination within neural ensembles as a pathophysiological basis of cognitive inflexibility in FXS. VIDEO ABSTRACT.

Lien vers le texte intégral (Open Access ou abonnement)

19. Valentino AL, LeBlanc LA, Raetz PB. {{Evaluation of stimulus intensity fading on reduction of rapid eating in a child with autism}}. {Journal of applied behavior analysis}. 2018; 51(1): 177-82.

This study assessed the effects of a vibrating pager on reduction of rapid eating. The study also evaluated two strategies for fading the pager, by intensity and by frequency. The pager was successful in decreasing the pace of eating to an appropriate level and the pager prompt was successfully faded. Fading by frequency was ineffective in maintaining an appropriate pace of eating while intensity fading was successful.

Lien vers le texte intégral (Open Access ou abonnement)

20. Wang Y, Wang L, Xu Q, Liu D, Chen L, Troje NF, He S, Jiang Y. {{Heritable aspects of biological motion perception and its covariation with autistic traits}}. {Proceedings of the National Academy of Sciences of the United States of America}. 2018; 115(8): 1937-42.

The ability to detect biological motion (BM) and decipher the meaning therein is essential to human survival and social interaction. However, at the individual level, we are not equally equipped with this ability. In particular, impaired BM perception and abnormal neural responses to BM have been observed in autism spectrum disorder (ASD), a highly heritable neurodevelopmental disorder characterized by devastating social deficits. Here, we examined the underlying sources of individual differences in two abilities fundamental to BM perception (i.e., the abilities to process local kinematic and global configurational information of BM) and explored whether BM perception shares a common genetic origin with autistic traits. Using the classical twin method, we found reliable genetic influences on BM perception and revealed a clear dissociation between its two components-whereas genes account for about 50% of the individual variation in local BM processing, global BM processing is largely shaped by environment. Critically, participants’ sensitivity to local BM cues was negatively correlated with their autistic traits through the dimension of social communication, with the covariation largely mediated by shared genetic effects. These findings demonstrate that the ability to process BM, especially with regard to its inherent kinetics, is heritable. They also advance our understanding of the sources of the linkage between autistic symptoms and BM perception deficits, opening up the possibility of treating the ability to process local BM information as a distinct hallmark of social cognition.

Lien vers le texte intégral (Open Access ou abonnement)