1. Bhatara A, Babikian T, Laugeson E, Tachdjian R, Sininger YS. {{Impaired Timing and Frequency Discrimination in High-functioning Autism Spectrum Disorders}}. {J Autism Dev Disord};2013 (Feb 6)
Individuals with autism spectrum disorders (ASD) frequently demonstrate preserved or enhanced frequency perception but impaired timing perception. The present study investigated the processing of spectral and temporal information in 12 adolescents with ASD and 15 age-matched controls. Participants completed two psychoacoustic tasks: one determined frequency difference limens, and the other determined gap detection thresholds. Results showed impaired frequency discrimination at the highest standard frequency in the ASD group but no overall difference between groups. However, when groups were defined by auditory hyper-sensitivity, a group difference arose. For the gap detection task, the ASD group demonstrated elevated thresholds. This supports previous research demonstrating a deficit in ASD in temporal perception and suggests a connection between hyper-sensitivity and frequency discrimination abilities.
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2. Bristot Silvestrin R, Bambini-Junior V, Galland F, Daniele Bobermim L, Quincozes-Santos A, Torres Abib R, Zanotto C, Batassini C, Brolese G, Goncalves CA, Riesgo R, Gottfried C. {{Animal model of autism induced by prenatal exposure to valproate: Altered glutamate metabolism in the hippocampus}}. {Brain Res};2013 (Feb 7);1495:52-60.
Autism spectrum disorders (ASD) are characterized by deficits in social interaction, language and communication impairments and repetitive and stereotyped behaviors, with involvement of several areas of the central nervous system (CNS), including hippocampus. Although neurons have been the target of most studies reported in the literature, recently, considerable attention has been centered upon the functionality and plasticity of glial cells, particularly astrocytes. These cells participate in normal brain development and also in neuropathological processes. The present work investigated hippocampi from 15 (P15) and 120 (P120) days old male rats prenatally exposed to valproic acid (VPA) as an animal model of autism. Herein, we analyzed astrocytic parameters such as glutamate transporters and glutamate uptake, glutamine synthetase (GS) activity and glutathione (GSH) content. In the VPA group glutamate uptake was unchanged at P15 and increased 160% at P120; the protein expression of GLAST did not change neither in P15 nor in P120, while GLT1 decreased 40% at P15 and increased 92% at P120; GS activity increased 43% at P15 and decreased 28% at P120; GSH content was unaltered at P15 and had a 27% increase at P120. These data highlight that the astrocytic clearance and destination of glutamate in the synaptic cleft might be altered in autism, pointing out important aspects to be considered from both pathophysiologic and pharmacological approaches in ASD.
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3. Farmer J, Reupert A. {{Understanding Autism and understanding my child with Autism: An evaluation of a group parent education program in rural Australia}}. {Aust J Rural Health};2013 (Feb);21(1):20-27.
OBJECTIVE: To describe and evaluate a six-session program provided to parents of children with Autism in rural Australia. The program was designed to improve parent’s knowledge and understanding of Autism, improve their confidence in managing their child and decrease parental anxiety. DESIGN: A self-constructed questionnaire administered pre- and post-intervention. SETTING: An early intervention centre in a large town in rural Victoria. PARTICIPANTS: Ninety-eight parents (or family members) of young children primarily aged 2-6 years of age, diagnosed with Autism. INTERVENTIONS: A ‘multi-stranded content’ program was offered over six evenings. Ten programs were conducted over six years. RESULTS: The pre- versus post-session analysis using a paired t-test on matched person-to-person parental responses (n = 92) showed significant increases in parental understanding of Autism and understanding of their own child (P < 0.001), and in understanding the communication, sensory, social, learning and behavioural features of Autism (P < 0.001). Significant increases in parental confidence and a significant reduction in parental anxiety were also shown (P < 0.001). Qualitative data indicated that parents valued learning about the general nature of Autism and sensory processing, and reported feeling less alone. CONCLUSIONS: The six-week program was successful in terms of its aims. Parent feedback indicated that ongoing parent education sessions at regular intervals would enhance the impact of the program.
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4. Scarpa A, Reyes NM, Patriquin MA, Lorenzi J, Hassenfeldt TA, Desai VJ, Kerkering KW. {{The Modified Checklist for Autism in Toddlers: Reliability in a Diverse Rural American Sample}}. {J Autism Dev Disord};2013 (Feb 6)
This study investigated the psychometric properties of the modified checklist for autism in toddlers (M-CHAT) in a diverse rural American low-socioeconomic status (SES) sample. Four hundred and forty-seven English (n = 335) and Spanish (n = 112) speaking caregivers completed the M-CHAT during their toddler’s 18- or 24-month well visit in a Southwest Virginia pediatric clinic. The M-CHAT did not show acceptable internal consistency in groups with low maternal education or minority status. Caregivers reporting low maternal education and minority status were more likely to endorse items suggestive of autism. These results indicate that the M-CHAT may require modifications to be more internally consistent and accurate across ethnic and educational groups in rural areas with low levels of SES. Recommendations to increase the utility of the M-CHAT are discussed.
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5. Watanabe H, Nakamura M, Ohno T, Itahashi T, Tanaka E, Ohta H, Yamada T, Kanai C, Iwanami A, Kato N, Hashimoto R. {{Altered orbitofrontal sulcogyral patterns in adult males with high-functioning autism spectrum disorders}}. {Soc Cogn Affect Neurosci};2013 (Feb 5)
Functions of the orbitofrontal cortex include diverse social, cognitive, and affective processes, many of which are abnormal in autism spectrum disorders (ASD). Recently, altered orbitofrontal sulcogyral patterns have been revealed in several psychiatric conditions such as schizophrenia, indicating a possibility that altered orbitofrontal sulcogyral morphology reflects abnormal neurodevelopment. However, the presence of sulcal alterations in ASD remains unexplored. Using structural MRI, subtypes of the « H-shaped » sulcus (Type I, II, and III, in order of frequency), posterior orbital sulcus (POS), and intermediate orbital sulcus were identified in each hemisphere of adult males with ASD (n=51) and matched normal controls (n=55) based on Chiavaras and Petrides (2000). ASD showed a significantly altered distribution of H-shaped sulcal subtypes in both hemispheres, with a significant increase of Type III. A significant alteration in the distribution of sulcal subtypes was also identified in the right hemisphere POS of ASD. Categorical regression analysis revealed that Type I and II expressions predicted a reduced total Autism-Spectrum Quotient score. Furthermore, Type I expression was associated with a reduced « attention to detail » subscale score. The results demonstrate that altered sulcogyral morphology can be a marker for abnormal neurodevelopment leading to the increased risk of developing autism.
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6. Yang Y, Pan C. {{Role of metabotropic glutamate receptor 7 in autism spectrum disorders: A pilot study}}. {Life Sci};2013 (Feb 7);92(2):149-153.
AIMS: The presence of genetic variants for autism spectrum disorders (ASDs) was investigated for the metabotropic glutamate receptor 7 (GRM7) gene in a case-control study. MAIN METHODS: Employing Affymetrix SNP microarrays, 297 single nucleotide polymorphisms (SNPs) covering the GRM7 gene were selected and analyzed in ASD patients (n=22), non-ASD patients [n=14, including seven patients with development delay (DD)/mental retardation (MR), four patients with language delay (LD), and three patients with attention deficit hyperactivity disorder (ADHD)] and normal control subjects (n=18). KEY FINDINGS: Twenty-one statistically significant SNPs with different inheritance models (recessive, dominant and allele) were demonstrated in three groups (ASDs vs. combined controls, ASDs vs. normal controls, ASDs vs. non-ASD patients). Associations of rs779867 and rs6782011 with ASDs were significant in all three groups and independent associations of rs779867 and rs6782011 with ASDs were found in the ASD vs. combined controls group, which are in modest linkage disequilibrium (D’>0.5). Further haplotype analysis showed that rs6782011/rs779867 (T-C) was statistically significantly related to ASDs in both the ASD vs. combined controls and ASD vs. normal controls groups (bootstrap P value=0.013, permutation P value=0.013 for the former group and bootstrap P value=0.002, permutation P value=0.020 for the latter). SIGNIFICANCE: These findings support a role for genetic variants within the GRM7 gene in 3p26.1 in ASDs.
