1. Bartlett CW, Flax JF, Fermano Z, Hare A, Hou L, Petrill SA, Buyske S, Brzustowicz LM. {{Gene x Gene Interaction in Shared Etiology of Autism and Specific Language Impairment}}. {Biol Psychiatry};2012 (Jun 13)
BACKGROUND: To examine the relationship between autism spectrum disorders (ASD) and specific language impairment (SLI), family studies typically take a comparative approach where families with one disease are examined for traits of the other disease. In contrast, the present report is the first study with both disorders required to be present in each family to provide a more direct test of the hypothesis of shared genetic etiology. METHODS: We behaviorally assessed 51 families including at least one person with ASD and at least one person with SLI (without ASD). Pedigree members were tested with 22 standardized measures of language and intelligence. Because these extended families include a nonshared environmental contrast, we calculated heritability, not just familiality, for each measure twice: 1) baseline heritability analysis, compared with; 2) heritability estimates after statistically removing ASD subjects from pedigrees. RESULTS: Significant increases in heritability on four supra-linguistic measures (including Pragmatic Judgment) and a composite language score but not on any other measures were observed when removing ASD subjects from the analysis, indicating differential genetic effects that are unique to ASD. Nongenetic explanations such as effects of ASD severity or measurement error or low score variability in ASD subjects were systematically ruled out, leaving the hypothesis of nonadditive genetics effects as the potential source of the heritability change caused by ASD. CONCLUSIONS: Although the data suggest genetic risk factors common to both SLI and ASD, there are effects that seem unique to ASD, possibly caused by nonadditive gene-gene interactions of shared risk loci.
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2. Camacho A, Espin JC, Nunez N, Simon R. {{Levetiracetam-induced reversible autistic regression}}. {Pediatr Neurol};2012 (Jul);47(1):65-67.
Levetiracetam is a commonly prescribed antiepileptic drug, and is generally well tolerated, but can eventually cause behavioral disturbances. These disturbances seem more frequent in children and in patients with a previous psychiatric history. We report on reversible autistic regression induced by levetiracetam in a 6-year-old girl with spastic cerebral palsy, mild cognitive deficiency, and focal epilepsy. She was diagnosed with pervasive developmental disorder, and demonstrated mild to moderate impairment in pragmatic language and interactions with peers. After the introduction of levetiracetam, she developed stereotypies, and her social and communicative skills deteriorated severely. She also exhibited mood lability. When the medication was discontinued, a dramatic response occurred, with a complete resolution of new abnormal findings. Levetiracetam can provoke unusual behavioral adverse effects in certain patients who are biologically more vulnerable.
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3. Coman D, Alessandri M, Gutierrez A, Novotny S, Boyd B, Hume K, Sperry L, Odom S. {{Commitment to Classroom Model Philosophy and Burnout Symptoms Among High Fidelity Teachers Implementing Preschool Programs for Children with Autism Spectrum Disorders}}. {J Autism Dev Disord};2012 (Jun 16)
Teacher commitment to classroom model philosophy and burnout were explored in a sample of 53 teachers implementing three preschool models at high levels of fidelity for students with autism: Treatment and Education of Autistic and Related Communication Handicapped Children (TEACCH); Learning Experiences and Alternative Program for Preschoolers and Their Parents (LEAP); and high quality special education programs (HQSEP’s). Relative to the other groups, LEAP teachers reported significantly higher levels of commitment to LEAP philosophy while TEACCH teachers did not report significantly higher commitment levels to TEACCH philosophy. Teachers in HQSEP’s reported similar levels of commitment to TEACCH and LEAP. Burnout was also low to moderate in this sample relative to normative data. Implications for school districts and teachers are discussed.
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4. Djukic A, Valicenti McDermott M, Mavrommatis K, Martins CL. {{Rett syndrome: basic features of visual processing-a pilot study of eye-tracking}}. {Pediatr Neurol};2012 (Jul);47(1):25-29.
Consistently observed « strong eye gaze » has not been validated as a means of communication in girls with Rett syndrome, ubiquitously affected by apraxia, unable to reply either verbally or manually to questions during formal psychologic assessment. We examined nonverbal cognitive abilities and basic features of visual processing (visual discrimination attention/memory) by analyzing patterns of visual fixation in 44 girls with Rett syndrome, compared with typical control subjects. To determine features of visual fixation patterns, multiple pictures (with the location of the salient and presence/absence of novel stimuli as variables) were presented on the screen of a TS120 eye-tracker. Of the 44, 35 (80%) calibrated and exhibited meaningful patterns of visual fixation. They looked longer at salient stimuli (cartoon, 2.8 +/- 2 seconds S.D., vs shape, 0.9 +/- 1.2 seconds S.D.; P = 0.02), regardless of their position on the screen. They recognized novel stimuli, decreasing the fixation time on the central image when another image appeared on the periphery of the slide (2.7 +/- 1 seconds S.D. vs 1.8 +/- 1 seconds S.D., P = 0.002). Eye-tracking provides a feasible method for cognitive assessment and new insights into the « hidden » abilities of individuals with Rett syndrome.
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5. Fields C. {{Do autism spectrum disorders involve a generalized object categorization and identification dysfunction?}}. {Med Hypotheses};2012 (Jun 13)
Experience-dependent learning of feature-based object categories, including entry-level categories such as « human being » and more specialized categories such as « family member », « pet » or « toy », is required to support correct object re-identification over time and hence to support social bonding, language learning, and the development of general life skills. It is hypothesized that activity imbalances between motion-analyzing and feature-analyzing components of the visuo-motor system resulting in hyper-activation of parahippocampal cortex relative to perirhinal cortex during the initial period of experience-dependent category learning in early infancy could lead to the construction of object categories dominated by trajectory information as opposed to feature information. It is shown that the deployment of trajectory-dominated object categories would disrupt normal object re-identification and produce developmental outcomes consistent with both the recognized symptoms and experimentally characterized cognitive-behavioral phenotypes of autism spectrum disorders. Further experiments to test the hypothesis and its potential clinical relevance are discussed.
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6. Hunsaker MR, Kim K, Willemsen R, Berman RF. {{CGG trinucleotide repeat length modulates neural plasticity and spatiotemporal processing in a mouse model of the fragile X premutation}}. {Hippocampus};2012 (Jun 18)
The fragile X premutation is a CGG repeat expansion on the FMR1 gene between 55 and 200 repeats in length. It has been proposed that impaired spatiotemporal function underlies cognitive deficits in genetic disorders, including the fragile X premutation. This study characterized the role of the premutation for cognitive function by demonstrating CGG KI mice with 70-198 CGG repeats show deficits across tasks requiring spatial and temporal pattern separation. To elucidate mechanisms whereby CGG repeats affect spatiotemporal processing, hippocampal slices were evaluated for LTP, LTD, and mGluR1/5 LTD. Increasing CGG repeat length modulated the induction of LTP, LTD, and mGluR1/5 LTD, as well as behavioral tasks emphasizing spatiotemporal processing. Despite the deficits in the induction of all forms of plasticity, there were no differences in expression of plasticity once evoked. These data provide evidence for a neurocognitive endophenotype in the CGG KI mouse model of the premutation in which CGG repeat length negatively modulates plasticity and spatiotemporal attention. (c) 2012 Wiley Periodicals, Inc.
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7. Peters-Scheffer N, Didden R, Korzilius H, Matson J. {{Cost comparison of early intensive behavioral intervention and treatment as usual for children with autism spectrum disorder in the Netherlands}}. {Res Dev Disabil};2012 (Jun 13);33(6):1763-1772.
Early intensive behavioral intervention (EIBI) may result in improved cognitive, adaptive and social functioning and reductions in autism severity and behavioral problems in children with Autism Spectrum Disorder (ASD). For a subset of children, normal functioning may be the result. However, due to the intensity (20-40h per week for 3 years with a low child staff ratio) implementation costs are high and can be controversial. Estimated costs for education, (supported) work and (sheltered) living for individuals with ASD in the Netherlands are applied in a cost-offset model. A compelling argument for the provision of EIBI is long term savings which are approximately euro 1,103,067 from age 3 to 65 years per individual with ASD. Extending these costs to the whole Dutch ASD population, cost savings of euro 109.2-euro 182 billion have been estimated, excluding costs associated with inflation.
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8. Ploog BO, Scharf A, Nelson D, Brooks PJ. {{Use of Computer-Assisted Technologies (CAT) to Enhance Social, Communicative, and Language Development in Children with Autism Spectrum Disorders}}. {J Autism Dev Disord};2012 (Jun 16)
Major advances in multimedia computer technology over the past decades have made sophisticated computer games readily available to the public. This, combined with the observation that most children, including those with autism spectrum disorders (ASD), show an affinity to computers, has led researchers to recognize the potential of computer technology as an effective and efficient tool in research and treatment. This paper reviews the use of computer-assisted technology (CAT), excluding strictly internet-based approaches, to enhance social, communicative, and language development in individuals with ASD by dividing the vast literature into four main areas: language, emotion recognition, theory of mind, and social skills. Although many studies illustrate the tremendous promise of CAT to enhance skills of individuals with ASD, most lack rigorous, scientific assessment of efficacy relative to non-CAT approaches.
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9. Rossignol DA, Bradstreet JJ, Van Dyke K, Schneider C, Freedenfeld SH, O’Hara N, Cave S, Buckley JA, Mumper EA, Frye RE. {{Hyperbaric oxygen treatment in autism spectrum disorders}}. {Med Gas Res};2012 (Jun 15);2(1):16.
ABSTRACT: Traditionally, hyperbaric oxygen treatment (HBOT) is indicated in several clinical disorders include decompression sickness, healing of problem wounds and arterial gas embolism. However, some investigators have used HBOT to treat individuals with autism spectrum disorders (ASD). A number of individuals with ASD possess certain physiological abnormalities that HBOT might ameliorate, including cerebral hypoperfusion, inflammation, mitochondrial dysfunction and oxidative stress. Studies of children with ASD have found positive changes in physiology and/or behavior from HBOT. For example, several studies have reported that HBOT improved cerebral perfusion, decreased markers of inflammation and did not worsen oxidative stress markers in children with ASD. Most studies of HBOT in children with ASD examined changes in behaviors and reported improvements in several behavioral domains although many of these studies were not controlled. Although the two trials employing a control group reported conflicting results, a recent systematic review noted several important distinctions between these trials. In the reviewed studies, HBOT had minimal adverse effects and was well tolerated. Studies which used a higher frequency of HBOT sessions (e.g., 10 sessions per week as opposed to 5 sessions per week) generally reported more significant improvements. Many of the studies had limitations which may have contributed to inconsistent findings across studies, including the use of many different standardized and non-standardized instruments, making it difficult to directly compare the results of studies or to know if there are specific areas of behavior in which HBOT is most effective. The variability in results between studies could also have been due to certain subgroups of children with ASD responding differently to HBOT. Most of the reviewed studies relied on changes in behavioral measurements, which may lag behind physiological changes. Additional studies enrolling children with ASD who have certain physiological abnormalities (such as inflammation, cerebral hypoperfusion, and mitochondrial dysfunction) and which measure changes in these physiological parameters would be helpful in further defining the effects of HBOT in ASD.
