1. Bottema-Beutel K, Yoder PJ, Hochman JM, Watson LR. {{The Role of Supported Joint Engagement and Parent Utterances in Language and Social Communication Development in Children with Autism Spectrum Disorder}}. {J Autism Dev Disord}. 2014.
This study examined associations between three parent-child engagement states and social communication, expressive language, and receptive language at 8 month follow-up, in 63 preschool-age children with autism spectrum disorder. We extend the literature on supported joint engagement by dividing this state into higher order (HSJE) and lower order types, with HSJE involving greater reciprocity in toy play. We also examined parents’ follow-in utterances that co-occurred with each state. We found that only HSJE predicts later social communication and expressive language, while object engagement predicts receptive language. HSJE combined with follow-in utterances (HSJE+FI) predicts all three outcomes when controlling for HSJE+FI in other engagement states. When controlling for total HSJE, HSJE+FI is predictive of receptive language.
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2. Broder-Fingert S, Ferrone CF, Giauque A, Connors SL. {{Residents’ Knowledge and Comfort With Caring for Children With Autism Spectrum Disorder}}. {Clin Pediatr (Phila)}. 2014.
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3. Davis JM, Searles VB, Anderson N, Keeney J, Dumas L, Sikela JM. {{DUF1220 Dosage Is Linearly Associated with Increasing Severity of the Three Primary Symptoms of Autism}}. {PLoS Genet}. 2014; 10(3): e1004241.
One of the three most frequently documented copy number variations associated with autism spectrum disorder (ASD) is a 1q21.1 duplication that encompasses sequences encoding DUF1220 protein domains, the dosage of which we previously implicated in increased human brain size. Further, individuals with ASD frequently display accelerated brain growth and a larger brain size that is also associated with increased symptom severity. Given these findings, we investigated the relationship between DUF1220 copy number and ASD severity, and here show that in individuals with ASD (n = 170), the copy number (dosage) of DUF1220 subtype CON1 is highly variable, ranging from 56 to 88 copies following a Gaussian distribution. More remarkably, in individuals with ASD CON1 copy number is also linearly associated, in a dose-response manner, with increased severity of each of the three primary symptoms of ASD: social deficits (p = 0.021), communicative impairments (p = 0.030), and repetitive behaviors (p = 0.047). These data indicate that DUF1220 protein domain (CON1) dosage has an ASD-wide effect and, as such, is likely to be a key component of a major pathway underlying ASD severity. Finally, these findings, by implicating the dosage of a previously unexamined, copy number polymorphic and brain evolution-related gene coding sequence in ASD severity, provide an important new direction for further research into the genetic factors underlying ASD.
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4. De Alwis D, Agrawal A, Reiersen AM, Constantino JN, Henders A, Martin NG, Lynskey MT. {{ADHD symptoms, autistic traits, and substance use and misuse in adult Australian twins}}. {J Stud Alcohol Drugs}. 2014; 75(2): 211-21.
ABSTRACT. Objective: Attention-deficit/hyperactivity disorder (ADHD) and autism spectrum disorder frequently co-occur. Several studies show increased risk of substance use disorders in ADHD, yet there is limited information related to how ADHD symptoms, autistic traits, and their combined effects are associated with nicotine, alcohol, and cannabis use and use disorders in the general population. Method: Cross-sectional interview and self-report questionnaire data from 3,080 young adult Australian twins (mean age 31.9 years) were used to assess ADHD symptoms, autistic traits, substance use, and substance use disorders. Substance use disorders-based on Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, criteria-were assessed in the full sample as well as in those who reported substance use. Logistic regression analyses were used for comparing the associations between ADHD symptoms, autistic traits, substance use, and substance misuse after conduct disorder, sex, age, and zygosity were controlled for. Results: Greater ADHD symptoms and autistic traits scores were associated with elevated levels of regular smoking; cannabis use; and nicotine, alcohol, and cannabis use disorders, even after conduct disorder was adjusted for. In contrast, for alcohol use, those with high autistic traits scores were less likely to report drinking to intoxication. However, upon initiation, and similar to the findings for nicotine and cannabis, they were at elevated risk for developing alcohol dependence. Conclusions: Increased liability to ADHD and elevated autistic traits scores were associated with substance use and misuse, with the exception of alcohol use. Given the social underpinnings of drinking, persons with autistic traits may be less likely to engage in it; however, upon engagement in drinking, their vulnerability to alcohol dependence is elevated. (J. Stud. Alcohol Drugs, 75, 211-221, 2014).
5. Fletcher-Watson S, McConnell F, Manola E, McConachie H. {{Interventions based on the Theory of Mind cognitive model for autism spectrum disorder (ASD)}}. {Cochrane Database Syst Rev}. 2014; 3: CD008785.
BACKGROUND: The ‘Theory of Mind’ (ToM) model suggests that people with autism spectrum disorder (ASD) have a profound difficulty understanding the minds of other people – their emotions, feelings, beliefs, and thoughts. As an explanation for some of the characteristic social and communication behaviours of people with ASD, this model has had a significant influence on research and practice. It implies that successful interventions to teach ToM could, in turn, have far-reaching effects on behaviours and outcome. OBJECTIVES: To review the efficacy of interventions based on the ToM model for individuals with ASD. SEARCH METHODS: In August 2013 we searched CENTRAL, Ovid MEDLINE, Embase, CINAHL, PsycINFO, ERIC, Social Services Abstracts, AutismData, and two trials registers. We also searched the reference lists of relevant papers, contacted authors who work in this field, and handsearched a number of journals. SELECTION CRITERIA: Review studies were selected on the basis that they reported on an applicable intervention (linked to ToM in one of four clearly-defined ways), presented new randomised controlled trial data, and participants had a confirmed diagnosis of an autism spectrum disorder. Studies were selected by two review authors independently and a third author arbitrated when necessary. DATA COLLECTION AND ANALYSIS: Risk of bias was evaluated and data were extracted by two review authors independently; a third author arbitrated when necessary. Most studies were not eligible for meta-analysis, the principal reason being mis-matching methodologies and outcome measures. Three small meta-analyses were carried out. MAIN RESULTS: Twenty-two randomised trials were included in the review (N = 695). Studies were highly variable in their country of origin, sample size, participant age, intervention delivery type, and outcome measures. Risk of bias was variable across categories. There were very few studies for which there was adequate blinding of participants and personnel, and some were also judged at high risk of bias in blinding of outcome assessors. There was also evidence of some bias in sequence generation and allocation concealment. Not all studies reported data that fell within the pre-defined primary outcome categories for the review, instead many studies reported measures which were intervention-specific (e.g. emotion recognition). The wide range of measures used within each outcome category and the mixed results from these measures introduced further complexity when interpreting results.Studies were grouped into four main categories according to intervention target/primary outcome measure. These were: emotion recognition studies, joint attention and social communication studies, imitation studies, and studies teaching ToM itself. Within the first two of these categories, a sub-set of studies were deemed suitable for meta-analysis for a limited number of key outcomes.There was very low quality evidence of a positive effect on measures of communication based on individual results from three studies. There was low quality evidence from 11 studies reporting mixed results of interventions on measures of social interaction, very low quality evidence from four studies reporting mixed results on measures of general communication, and very low quality evidence from four studies reporting mixed results on measures of ToM ability. The meta-analysis results we were able to generate showed that interventions targeting emotion recognition across age groups and working with people within the average range of intellectual ability had a positive effect on the target skill, measured by a test using photographs of faces (mean increase of 0.75 points, 95% confidence interval (CI) 0.22 to 1.29 points, Z = 2.75, P < 0.006, four studies, N = 105). Therapist-led joint attention interventions can promote production of more joint attention behaviours within adult-child interaction (mean increase of 0.55 points, 95% CI 0.11 to 0.99 points, Z = 2.45, P value = 0.01, two studies, N = 88). Further analysis undermines this conclusion somewhat by demonstrating that there was no clear evidence that intervention can have an effect on joint attention initiations as measured using a standardised assessment tool (mean increase of 0.23 points, 95% CI -0.48 to 0.94 points, Z = 0.63, P value = 0.53, three studies, N = 92). No adverse effects were apparent. AUTHORS’ CONCLUSIONS: While there is some evidence that ToM, or a precursor skill, can be taught to people with ASD, there is little evidence of maintenance of that skill, generalisation to other settings, or developmental effects on related skills. Furthermore, inconsistency in findings and measurement means that evidence has been graded of ‘very low’ or ‘low’ quality and we cannot be confident that suggestions of positive effects will be sustained as high-quality evidence accumulates. Further longitudinal designs and larger samples are needed to help elucidate both the efficacy of ToM-linked interventions and the explanatory value of the ToM model itself. It is possible that the continuing refinement of the ToM model will lead to better interventions which have a greater impact on development than those investigated to date.
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6. 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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7. Horlin C, Black M, Falkmer M, Falkmer T. {{Proficiency of individuals with autism spectrum disorder at disembedding figures: A systematic review}}. {Dev Neurorehabil}. 2014.
Abstract Objective: This systematic review examines the proficiency and visual search strategies of individuals with autism spectrum disorders (ASD) while disembedding figures and whether they differ from typical controls and other comparative samples. Methods: Five databases, including Proquest, Psychinfo, Medline, CINAHL and Science Direct were used to identify published studies meeting the inclusion and exclusion criteria. Results: Twenty articles were included in the review, the majority of which matched participants by mental age. Outcomes discussed were time taken to identify targets, the number correctly identified, and fixation frequency and duration. Conclusions: Individuals with ASD perform at the same speed or faster than controls and other clinical samples. However, there appear to be no differences between individuals with ASD and controls for number of correctly identified targets. Only one study examined visual search strategies and suggests that individuals with ASD exhibit shorter first and final fixations to targets compared with controls.
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8. Keown K, Bothwell J, Jain S. {{Nutritional implications of selective eating in a child with autism spectrum disorder}}. {BMJ Case Rep}. 2014; 2014.
A 4-year-old boy attending the autism assessment service was identified to have a restricted diet. His food diary documented that he ate a narrow range of foods and consumed excessive quantities of carrot juice (excess 2.5 L daily). Physical examination showed that the boy had a florid orange discolouration of his skin, growth parameters were <91st centile for weight, >50th centile for height and head circumference. Blood investigations showed a raised serum carotene level and vitamin D deficiency. He was referred for urgent specialist input from dietetics and the other disciplines within the autism intervention team.
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9. Kikuchi M, Yoshimura Y, Hiraishi H, Munesue T, Hashimoto T, Tsubokawa T, Takahashi T, Suzuki M, Higashida H, Minabe Y. {{Reduced long-range functional connectivity in young children with autism spectrum disorder}}. {Soc Cogn Affect Neurosci}. 2014.
Autism spectrum disorder (ASD) is often described as a disorder of aberrant neural connectivity. Although it is important to study the pathophysiology of ASD in the developing cortex, the functional connectivity in the brains of young children with ASD has not been well studied. In the present study, brain activity was measured non-invasively during consciousness in 50 young human children with ASD and 50 age- and gender-matched typically developing human (TD) children. We employed a custom child-sized magnetoencephalography (MEG) system in which sensors were located as close to the brain as possible for optimal recording in young children. We focused on theta band oscillations because they are thought to be involved in long-range networks associated with higher cognitive processes. The ASD group showed significantly reduced connectivity between the left anterior and the right posterior areas, exhibiting a decrease in the coherence of theta band (6 Hz) oscillations compared with the TD group. This reduction in coherence was significantly correlated with clinical severity in right-handed children with ASD. This is the first study to demonstrate reduced long-range functional connectivity in conscious young children with ASD using a novel MEG approach.
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10. 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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11. Miller Kuhaneck H, Britner PA. {{A preliminary investigation of the relationship between sensory processing and social play in autism spectrum disorder}}. {OTJR (Thorofare N J)}. 2013; 33(3): 159-67.
There are well-documented play deficits in autism beginning with infant object and social play. To create effective interventions, the predictors of play deficits in autism must be established. Individuals with autism spectrum disorder (ASD) frequently report sensory processing difficulties including poor praxis; however, these are potential predictors of play that have not been well studied. Using a data set of 162 individuals with ASD, this study examined the direct and indirect relationships between sensory processing and social play performance via structural equation modeling. The best fitting model suggested that sensory system functions predict praxis and play in combination, providing preliminary evidence that sensory functions are related to social play in combination with praxis in children with ASD. The findings suggest future avenues for research. [OTJR: Occupation, Participation and Health 2013;33(3):159-167.].
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12. Pearson A, Marsh L, Hamilton A, Ropar D. {{Spatial Transformations of Bodies and Objects in Adults with Autism Spectrum Disorder}}. {J Autism Dev Disord}. 2014.
Previous research into autism spectrum disorder (ASD) has shown people with autism to be impaired at visual perspective taking. However it is still unclear to what extent the spatial mechanisms underlying this ability contribute to these difficulties. In the current experiment we examine spatial transformations in adults with ASD and typical adults. Participants performed egocentric transformations and mental rotation of bodies and cars. Results indicated that participants with ASD had general perceptual differences impacting on response times across tasks. However, they also showed more specific differences in the egocentric task suggesting particular difficulty with using the self as a reference frame. These findings suggest that impaired perspective taking could be grounded in difficulty with the spatial transformation used to imagine the self in someone else’s place.
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13. Rayner C. {{Video-based intervention for children with autism: Towards improved assessment of pre-requisite imitation skills}}. {Dev Neurorehabil}. 2014.
Abstract Objective: To explore the relationship between responses to imitation assessment and video-based intervention (VBI) in children with autism. Methods: Interview- and observation-based imitation assessments were conducted for five boys with autism prior to VBI across three studies. In two of the three studies, the boys’ imitative responses to videos with an animated model and a human model were also compared. Results: Participants who were assessed to have strong imitation skills were also those who responded more positively to VBI. No clear differences were reported in the boys’ responses to the equivalent videos with the animated model and the human model. Conclusions: The level of imitation skills required for successful VBI is relative to the target behaviour. Revision of existing imitation assessment measures, as well as development and validation of more comprehensive measures is warranted for use in conjunction with VBI.
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14. Schaefer-Campion C, Johnson NL. {{Fostering Ambulation for a Preschool Child with Rett Syndrome: A Case Report}}. {Phys Occup Ther Pediatr}. 2014.
ABSTRACT Children with Rett Syndrome (RS) have neuromotor impairments that impact their mobility. Poor hand function among children with RS limits the selection of an assistive device for ambulation. Purpose: The purpose of this case report is to describe the process of selecting an assistive device for a child with RS to promote ambulation. Method: This single subject case reports on a 5-year-old girl with RS at a suburban mid-western early childhood special education setting. Results: The child in this case was able to walk the farthest distances with a metal toy shopping cart and then with an anterior facing four-wheeled walker. Conclusion: The outcome suggests that physical therapists and health professionals caring for young children with RS consider using a metal toy shopping cart to establish and practice ambulation prior to selection of a longer term, adjustable anterior facing walker like the one in this case report.
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15. Smith LO, Elder JH, Storch EA, Rowe MA. {{Predictors of sense of coherence in typically developing adolescent siblings of individuals with autism spectrum disorder}}. {J Intellect Disabil Res}. 2014.
BACKGROUND: Children with autism spectrum disorder (ASD) may be a stressor for family members yet there is little published research on the impact of having a child with ASD on their typically developing (TD) adolescent siblings. According to Antonovsky’s salutogenic model, a strong sense of coherence leads to the view that the stressor is a manageable challenge rather than a burden and promotes healthier adaptation. This study examines the relationship between stress, TD sibling resources and the sense of coherence in TD siblings. METHOD: This quantitative mail-based study uses a survey methodology, analysing the responses of TD adolescent siblings (n = 96) of individuals with autism, Asperger’s syndrome, or pervasive developmental disorder – not otherwise specified to several rating scales. Adolescent siblings, ages 11 to 18 years, completed the Adolescent Coping Orientation for Problem Experience (ACOPE), Network of Relationship Inventory – Social Provision Version (NRI-SPV), Youth Self Report (YSR), and Sense of Coherence (SOC) instruments; parents completed the Child Autism Rating Scale – 2nd Edition (CARS-2). RESULTS: The salutogenesis model was used to guide and inform this research. Findings suggested the following: (a) the stress of ASD severity and resource of adjustment are related in TD adolescent siblings; (b) TD sibling adjustment has a strong relationship with sense of coherence levels; and (c) a greater number of positive coping strategies buffer TD sibling coherence levels when ASD severity scores are high. CONCLUSIONS: ASD severity and TD adolescent sibling resources influence sense of coherence in adolescent TD siblings of individuals with ASD.
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16. Tavassoli T, Kolevzon A, Wang AT, Curchack-Lichtin J, Halpern D, Schwartz L, Soffes S, Bush L, Grodberg D, Cai G, Buxbaum JD. {{De novo SCN2A splice site mutation in a boy with Autism spectrum disorder}}. {BMC Med Genet}. 2014; 15(1): 35.
BACKGROUND: SCN2A is a gene that codes for the alpha subunit of voltage-gated, type II sodium channels, and is highly expressed in the brain. Sodium channel disruptions, such as mutations in SCN2A, may play an important role in psychiatric disorders. Recently, de novo SCN2A mutations in autism spectrum disorder (ASD) have been identified. The current study characterizes a de novo splice site mutation in SCN2A that alters mRNA and protein products. CASE PRESENTATION: We describe results from clinical and genetic characterizations of a seven-year-old boy with ASD. Psychiatric interview and gold standard autism diagnostic instruments (ADOS and ADI-R) were used to confirm ASD diagnosis, in addition to performing standardized cognitive and adaptive functioning assessments (Leiter-R and Vineland Adaptive Behavior Scale), and sensory reactivity assessments (Sensory Profile and Sensory Processing Scales). Genetic testing by whole exome sequencing revealed four de novo events, including a splice site mutation c.476 + 1G > A in SCN2A, a missense mutation (c.2263G > A) causing a p.V755I change in the TLE1 gene, and two synonymous mutations (c.2943A > G in the BUB1 gene, and c.1254 T > A in C10orf68 gene). The de novo SCN2A splice site mutation produced a stop codon 10 amino acids downstream, possibly resulting in a truncated protein and/or a nonsense-mediated mRNA decay. The participant met new DSM-5 criteria for ASD, presenting with social and communication impairment, repetitive behaviors, and sensory reactivity issues. The participant’s adaptive and cognitive skills fell in the low range of functioning. CONCLUSION: This report indicates that a splice site mutation in SCN2A might be contributing to the risk of ASD. Describing the specific phenotype associated with SCN2A mutations might help to reduce heterogeneity seen in ASD.
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17. van Rijn S, Stockmann L, Van Buggenhout G, van Ravenswaaij-Arts C, Swaab H. {{Social cognition and underlying cognitive mechanisms in children with an extra X chromosome: a comparison with autism spectrum disorder}}. {Genes Brain Behav}. 2014.
Individuals with an extra X chromosome are at increased risk for autism symptoms. This study is the first to assess Theory of Mind and facial affect labeling in children with an extra X chromosome. Forty-six children with an extra X chromosome (29 boys with Klinefelter syndrome and 17 girls with Trisomy X), 56 children with ASD, and 88 non-clinical controls, aged 9 to 18 years, were included. Similar to children with ASD, children with an extra X chromosome showed significant impairments in social cognition. Regression analyses showed that different cognitive functions predicted social cognitive skills in the extra X and ASD groups. The social cognitive deficits were similar for boys and girls with an extra X chromosome, and not specific for a subgroup with high (ADI-R) autism scores. Thus, children with an extra X chromosome show social cognitive deficits, which may contribute to social dysfunction, not only in children showing a developmental pattern that is ‘typical’ for autism, but also in those showing mild or late presenting autism symptoms. Our findings may also help explain variance in type of social deficit: Children may show similar social difficulties, but these may arise as a consequence of different underlying information processing deficits.
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18. Wang XS, Peng CZ, Cai WJ, Xia J, Jin D, Dai Y, Luo XG, Klyachko VA, Deng PY. {{Activity-dependent regulation of release probability at excitatory hippocampal synapses: a crucial role of fragile X mental retardation protein in neurotransmission}}. {Eur J Neurosci}. 2014.
Transcriptional silencing of the Fmr1 gene encoding fragile X mental retardation protein (FMRP) causes fragile X syndrome (FXS), the most common form of inherited intellectual disability and the leading genetic cause of autism. FMRP has been suggested to play important roles in regulating neurotransmission and short-term synaptic plasticity at excitatory hippocampal and cortical synapses. However, the origins and mechanisms of these FMRP actions remain incompletely understood, and the role of FMRP in regulating synaptic release probability and presynaptic function remains debated. Here we used variance-mean analysis and peak-scaled nonstationary variance analysis to examine changes in both presynaptic and postsynaptic parameters during repetitive activity at excitatory CA3-CA1 hippocampal synapses in a mouse model of FXS. Our analyses revealed that loss of FMRP did not affect the basal release probability or basal synaptic transmission, but caused an abnormally elevated release probability specifically during repetitive activity. These abnormalities were not accompanied by changes in excitatory postsynaptic current kinetics, quantal size or postsynaptic alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor conductance. Our results thus indicate that FMRP regulates neurotransmission at excitatory hippocampal synapses specifically during repetitive activity via modulation of release probability in a presynaptic manner. Our study suggests that FMRP function in regulating neurotransmitter release is an activity-dependent phenomenon that may contribute to the pathophysiology of FXS.
