1. Cannell JJ, Grant WB. {{What is the role of vitamin D in autism?}}. {Dermato-endocrinology}. 2013 Jan 1;5(1):199-204.
A growing body of literature suggests that higher serum 25-hydroxyvitamin D [25(OH)D] concentrations, either in utero or in early life, may reduce the risk of autism. For example, an ecological study in the companion paper inversely correlated solar UV-B doses in the United States with prevalence of autism among those aged 6-17 y. That study proposed that vitamin D deficiency during pregnancy could account for this finding, although the findings are also consistent with childhood vitamin D deficiency contributing to the condition. Also, in a recent study, children with autism had lower serum 25(OH)D concentrations than did control subjects (19 vs. 33 ng/ml), despite parents of each group reporting the same amount of sun exposure. The same study found highly significant inverse correlations between 25(OH)D and autism rating scales and between 25(OH)D and levels of an antineuronal antibody. This finding indicates that higher serum 25(OH)D concentrations may reduce the symptoms of established autism. Because activated vitamin D, a secosteroid, upregulates DNA-repair genes, vitamin D deficiency during development may inhibit the repair of de novo DNA mutations in fetuses and infants and thus contribute to risk of autism. Vitamin D might also reduce the risk or severity of autism through its anti-inflammatory actions, antiautoimmune effects, increasing seizure threshold, increasing T-regulatory cells, protecting the mitochondria, and upregulating glutathione, which scavenges oxidative by-products and chelates (captures and excretes) heavy metals. Vitamin D deficiency during pregnancy and childhood is a widespread and growing epidemic.
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2. Chiocchetti AG, Bour HS, Freitag CM. {{Glutamatergic candidate genes in autism spectrum disorder: an overview}}. {Journal of neural transmission (Vienna, Austria : 1996)}. 2014 Feb 4.
Autism spectrum disorders (ASD) are neurodevelopmental disorders with early onset in childhood. Most of the risk for ASD can be explained by genetic variants that act in interaction with biological environmental risk factors. However, the architecture of the genetic components is still unclear. Genetic studies and subsequent systems biological approaches described converging functional effects of identified genes towards pathways relevant for neuronal signalling. Mouse models suggest an aberrant synaptic plasticity at the neuropathological level, which is believed to be conferred by dysregulation of long-term potentiation or depression of neuronal connections. A central pathway regulating these mechanisms is glutamatergic signalling. Here, we hypothesized that susceptibility genes for ASD are enriched for components of this pathway. To further understand the impact of ASD risk genes on the glutamatergic pathway, we performed a systematic review using the literature database « pubmed » and the « AutismKB » knowledgebase. We provide an overview of the glutamatergic system in typical brain function and development, and summarize findings from linkage, association, copy number variants, and sequencing studies in ASD to provide a comprehensive picture of the glutamatergic landscape of ASD genetics. Genetic variants associated with ASD were enriched in glutamatergic pathways, affecting receptor signalling, metabolism and transport. Furthermore, in genetically modified mouse models for ASD, pharmacological compounds acting on ionotropic or metabotropic receptor activity are able to rescue ASD reminscent phenotypes. We conclude that glutamatergic genetic risk factors for ASD show a complex pattern and further studies are needed to fully understand its mechanisms, before translation of findings into clinical applications and individualized treatment approaches will be possible.
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3. Clawson A, Clayson PE, Worsham W, Johnston O, South M, Larson MJ. {{How about watching others? Observation of error-related feedback by others in Autism Spectrum Disorders}}. {International journal of psychophysiology : official journal of the International Organization of Psychophysiology}. 2014 Jan 31.
Research indicates that individuals with autism spectrum disorders (ASD) may have a reduced ability to utilize performance feedback to regulate their behavior; however, it is unclear to what degree alterations in the environmental context affect feedback processing and contribute to the symptoms of ASD. We utilized the observational FRN (oFRN), an event-related potential (ERP) component that putatively indexes feedback processing while observing feedback directed toward another person, to examine the influence of motivational and social demands on feedback processing in ASD. High-density electroencephalogram recordings were collected from 38 youth with ASD and 31 control participants similar on age and IQ while they observed a confederate performing a modified Eriksen Flanker task. Participants were instructed to count the confederate’s errors and were told they would be awarded based on performance: the confederate would either earn points for the participant or herself. Both groups showed robust oFRN activity on traditional scalp-electrode waveforms and waveforms identified using temporospatial principal components analysis. Amplitude of oFRN did not differentiate groups. Results remained non-significant when comparing medicated to non-medicated participants. There were no significant correlations between oFRN amplitudes, autism symptom severity, and anxiety symptoms. Findings suggest that the social context of the task and motivational significance of the confederate’s performance did not limit feedback processing in ASD. Future research in which the context is manipulated further is warranted to determine whether increased environmental complexity influences feedback processing in ASD.
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4. Coury DL, Swedo SE, Thurm AE, Miller DT, Veenstra-Vanderweele JM, Carbone PS, Taylor JL. {{Treating the Whole Person With Autism: The Proceedings of the Autism Speaks National Autism Conference}}. {Current problems in pediatric and adolescent health care}. 2014 Feb;44(2):26-47.
The identification of autism spectrum disorders has increased dramatically over the past decade, with the latest estimates indicating prevalence as high as 1 in 54 boys. There is greater awareness of medical conditions that co-occur with autism and expansion of treatment options. Closer scrutiny has led to refinement of the diagnostic criteria, and there have been advances in genetics examining potential causal factors. Transition to adulthood is an area of growing concern, and professionals and families require guidance on this issue. This article summarizes the proceedings of the Autism Speaks conference on Treating the Whole Person with Autism: Care across the Lifespan. The conference was organized with the intent of providing a forum for both families and professionals to learn about the most current research in the field. Dr. Sue Swedo provides important background information regarding the changes in the diagnostic criteria for autism spectrum disorders. She particularly deals with the concerns of individuals and families that their autism diagnosis may change. Recommendations for genetic testing and its interpretation are provided by Dr. David Miller. His discussion helps make sense of the utility of genetic testing for ASD, along with demonstration of the complexity of determining which genetic factors are doing what and through which pathways. Dr. Jeremy Veenstra-VanderWeele provides useful background information on how medicines are initially identified and for what purpose and goes on to describe the present and future treatments in pharmacology. Medical issues are addressed by Dr. Paul Carbone, especially the coordination of comprehensive services through the medical home model of care. Dr. Julie Lounds Taylor concludes with guidance on preparation for adulthood, a topic of great importance to families as their child matures and for the professionals who will help guide this transition.
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5. Grant WB, Cannell JJ. {{Autism prevalence in the United States with respect to solar UV-B doses: An ecological study}}. {Dermato-endocrinology}. 2013 Jan 1;5(1):159-64.
Evidence is mounting that vitamin D deficiency is intimately involved in autism. We report on autism prevalence by US state for those aged 6-17 y in 2010 with respect to indices of solar UV-B (UVB) doses. We calculated autism prevalence rates for white, black and Asian Americans by using total prevalence and relative populations of minors for each ethnic group by state. Analyses omit AK and HI (considered extreme cases), WY (no data), along with AZ and ND for black Americans (low numbers) and DC, ME, MT, ND and SD for Asian Americans (low numbers). For white Americans, the regression coefficient for solar UVB doses and autism prevalence ranged from -0.52 in January to -0.57 in October. For black Americans, the regression coefficient for latitude was 0.61, whereas those for solar UVB ranged from -0.55 to -0.61. For Asian Americans, the values for solar UVB ranged from -0.28 to -0.38. The inverse correlation between solar UVB and autism prevalence is similar to that for many types of cancer in the US. The journal literature indicates that adverse effects on fetal brain development during pregnancy due to vitamin D deficiency can explain these findings. However, we cannot rule out a role of vitamin D deficiency in early life. These results add to the evidence that vitamin D deficiency may be an important risk factor for autism and suggest that pregnant women and autistic individuals raise their serum 25-hydroxyvitamin D concentrations above 30 ng/ml.
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6. Lim CS, Hoang ET, Viar KE, Stornetta RL, Scott MM, Zhu JJ. {{Pharmacological rescue of Ras signaling, GluA1-dependent synaptic plasticity, and learning deficits in a fragile X model}}. {Genes & development}. 2014 Feb 1;28(3):273-89.
Fragile X syndrome, caused by the loss of Fmr1 gene function, is the most common form of inherited mental retardation, with no effective treatment. Using a tractable animal model, we investigated mechanisms of action of a few FDA-approved psychoactive drugs that modestly benefit the cognitive performance in fragile X patients. Here we report that compounds activating serotonin (5HT) subtype 2B receptors (5HT2B-Rs) or dopamine (DA) subtype 1-like receptors (D1-Rs) and/or those inhibiting 5HT2A-Rs or D2-Rs moderately enhance Ras-PI3K/PKB signaling input, GluA1-dependent synaptic plasticity, and learning in Fmr1 knockout mice. Unexpectedly, combinations of these 5HT and DA compounds at low doses synergistically stimulate Ras-PI3K/PKB signal transduction and GluA1-dependent synaptic plasticity and remarkably restore normal learning in Fmr1 knockout mice without causing anxiety-related side effects. These findings suggest that properly dosed and combined FDA-approved psychoactive drugs may effectively treat the cognitive impairment associated with fragile X syndrome.
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7. Maximo JO, Cadena EJ, Kana RK. {{The Implications of Brain Connectivity in the Neuropsychology of Autism}}. {Neuropsychology review}. 2014 Feb 5.
Autism is a neurodevelopmental disorder that has been associated with atypical brain functioning. Functional connectivity MRI (fcMRI) studies examining neural networks in autism have seen an exponential rise over the last decade. Such investigations have led to the characterization of autism as a distributed neural systems disorder. Studies have found widespread cortical underconnectivity, local overconnectivity, and mixed results suggesting disrupted brain connectivity as a potential neural signature of autism. In this review, we summarize the findings of previous fcMRI studies in autism with a detailed examination of their methodology, in order to better understand its potential and to delineate the pitfalls. We also address how a multimodal neuroimaging approach (incorporating different measures of brain connectivity) may help characterize the complex neurobiology of autism at a global level. Finally, we also address the potential of neuroimaging-based markers in assisting neuropsychological assessment of autism. The quest for a neural marker for autism is still ongoing, yet new findings suggest that aberrant brain connectivity may be a promising candidate.
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8. Miranda ML, Anthopolos R, Gregory SG. {{Induction or augmentation of labor and autism-reply}}. {JAMA pediatrics}. 2014 Feb 1;168(2):191-2.
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9. Nah YH, Young RL, Brewer N, Berlingeri G. {{Autism Detection in Early Childhood (ADEC): Reliability and Validity Data for a Level 2 Screening Tool for Autistic Disorder}}. {Psychological assessment}. 2014 Feb 3.
The Autism Detection in Early Childhood (ADEC; Young, 2007) was developed as a Level 2 clinician-administered autistic disorder (AD) screening tool that was time-efficient, suitable for children under 3 years, easy to administer, and suitable for persons with minimal training and experience with AD. A best estimate clinical Diagnostic and Statistical Manual of Mental Disorders (4th ed., text rev.; DSM-IV-TR; American Psychiatric Association, 2000) diagnosis of AD was made for 70 children using all available information and assessment results, except for the ADEC data. A screening study compared these children on the ADEC with 57 children with other developmental disorders and 64 typically developing children. Results indicated high internal consistency (alpha = .91). Interrater reliability and test-retest reliability of the ADEC were also adequate. ADEC scores reliably discriminated different diagnostic groups after controlling for nonverbal IQ and Vineland Adaptive Behavior Composite scores. Construct validity (using exploratory factor analysis) and concurrent validity using performance on the Autism Diagnostic Observation Schedule (Lord et al., 2000), the Autism Diagnostic Interview-Revised (Le Couteur, Lord, & Rutter, 2003), and DSM-IV-TR criteria were also demonstrated. Signal detection analysis identified the optimal ADEC cutoff score, with the ADEC identifying all children who had an AD (N = 70, sensitivity = 1.0) but overincluding children with other disabilities (N = 13, specificity ranging from .74 to .90). Together, the reliability and validity data indicate that the ADEC has potential to be established as a suitable and efficient screening tool for infants with AD. (PsycINFO Database Record (c) 2014 APA, all rights reserved).
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10. Neiworth JJ, Whillock KM, Kim SH, Greenberg JR, Jones KB, Patel AR, Steefel-Moore DL, Shaw AJ, Rupert DD, Gauer JL, Kudura AG. {{Gestalt Principle Use in College Students, Children With Autism, Toddlers (Homo sapiens), and Cotton Top Tamarins (Saguinus oedipus)}}. {Journal of comparative psychology (Washington, DC : 1983)}. 2014 Feb 3.
The use of Gestalt principles of proximity, similarity, and closure to recognize objects by configural superiority was examined in college students, low- and high-functioning children with autism, toddlers, and adult cotton top tamarin monkeys. At issue was whether the monkeys showed differences from humans in perceptual processing and whether they showed any similarities with clinical or developmental groups. The method required a pointing response to discriminate an odd item in a 4-item visual display. All subjects were trained to a high accuracy to point to the odd item before being tested with graphic stimuli that differentiated feature changes based on configural superiority. The results were that college students and high-functioning children with autism responded faster and more accurately to trials in which the odd item was easily noticed by the use of Gestalt principles and configural superiority. Toddlers also responded more accurately to the Gestalt trials, but without being faster at making the response. Low-functioning children with autism and tamarins showed no advantage to Gestalt trials but exhibited different processing styles. The implications of these findings to track the evolution of human perception and to develop a primate model for the perceptual deficits of autism are discussed. (PsycINFO Database Record (c) 2014 APA, all rights reserved).
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11. Niu YQ, Yang JC, Hall DA, Leehey MA, Tassone F, Olichney JM, Hagerman RJ, Zhang L. {{Parkinsonism in fragile X-associated tremor/ataxia syndrome (FXTAS): Revisited}}. {Parkinsonism & related disorders}. 2014 Jan 18.
BACKGROUND: Parkinsonian features have been used as a minor diagnostic criterion for fragile X-associated tremor/ataxia syndrome (FXTAS). However, prior studies have examined parkinsonism (defined as having bradykinesia with at least rest tremor or postural instability) mostly in premutation carriers without a diagnosis of FXTAS. The current study was intended to elaborate this important aspect of the FXTAS spectrum, and to quantify the relationships between parkinsonism, FXTAS clinical staging and genetic/molecular measures. METHODS: Thirty eight (38) FXTAS patients and 10 age-matched normal controls underwent a detailed neurological examination that included all but one item (i.e. rigidity) of the motor section of the Unified Parkinson’s Disease Rating Scale (UPDRS). RESULTS: The FXTAS patient group displayed substantially higher prevalence of parkinsonian features including body bradykinesia (57%) and rest tremor (26%), compared to the control group. Furthermore, parkinsonism was identified in 29% of FXTAS patients. Across all patients, body bradykinesia scores significantly correlated with FXTAS clinical stage, FMR1 mRNA level, and ataxic gait of cerebellar origin, while postural instability was associated with intention tremor. INTERPRETATION: Parkinsonian features in FXTAS appear to be characterized as bradykinesia concurrent with cerebellar gait ataxia, postural instability accompanied by intention tremor, and frequent rest tremor, representing distinctive patterns that highlight the need for further clinical studies including genetic testing for the FMR1 premutation. The association between FMR1 mRNA level and bradykinesia implicates pathophysiological mechanisms which may link FMR1 mRNA toxicity, dopamine deficiency and parkinsonism in FXTAS.
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12. Saade GR, Sibai BM, Silver R. {{Induction or augmentation of labor and autism}}. {JAMA pediatrics}. 2014 Feb 1;168(2):190-1.
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13. Sims T, Neufeld J, Johnstone T, Chakrabarti B. {{Autistic traits modulate frontostriatal connectivity during processing of rewarding faces}}. {Social cognitive and affective neuroscience}. 2014 Feb 3.
Deficits in facial mimicry have been widely reported in autism. Some studies have suggested that these deficits are restricted to spontaneous mimicry and do not extend to volitional mimicry. We bridge these apparently inconsistent observations, by testing the impact of reward value on neural indices of mimicry, and how autistic traits modulate this impact. Neutral faces were conditioned with high and low reward. Subsequently, functional connectivity between the ventral striatum (VS) and inferior frontal gyrus (IFG) was measured whilst neurotypical adults (n = 30) watched happy expressions made by these conditioned faces. We found greater VS-IFG connectivity in response to high-reward vs. low-reward happy faces. This difference was negatively proportional to autistic traits, suggesting that reduced spontaneous mimicry of social stimuli seen in autism, maybe related to a failure in the modulation of the mirror system by the reward system rather than a circumscribed deficit in the mirror system.
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14. Stitely ML. {{Induction or augmentation of labor and autism}}. {JAMA pediatrics}. 2014 Feb 1;168(2):189-90.
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15. Vintzileos AM, Ananth CV. {{Induction or augmentation of labor and autism}}. {JAMA pediatrics}. 2014 Feb 1;168(2):190.
