Pubmed du 30/06/09

Pubmed du jour

2009-06-30 12:03:50

1. Ashwin E, Ashwin C, Tavassoli T, Chakrabarti B, Baron-Cohen S. {{Eagle-eyed Visual Acuity in Autism}}. {Biol Psychiatry};2009 (Jun 25)

2. Crewther DP, Sutherland A. {{The More He Looked Inside, the More Piglet Wasn’t There: Is Autism Really Blessed with Visual Hyperacuity?}} {Biol Psychiatry};2009 (Jun 25)

3. Freitag CM, Agelopoulos K, Huy E, Rothermundt M, Krakowitzky P, Meyer J, Deckert J, von Gontard A, Hohoff C. {{Adenosine A(2A) receptor gene (ADORA2A) variants may increase autistic symptoms and anxiety in autism spectrum disorder}}. {Eur Child Adolesc Psychiatry};2009 (Jun 30)

Autism spectrum disorders (ASDs) are heterogeneous disorders presenting with increased rates of anxiety. The adenosine A(2A) receptor gene (ADORA2A) is associated with panic disorder and is located on chromosome 22q11.23. Its gene product, the adenosine A(2A) receptor, is strongly expressed in the caudate nucleus, which also is involved in ASD. As autistic symptoms are increased in individuals with 22q11.2 deletion syndrome, and large 22q11.2 deletions and duplications have been observed in ASD individuals, in this study, 98 individuals with ASD and 234 control individuals were genotyped for eight single-nucleotide polymorphisms in ADORA2A. Nominal association with the disorder was observed for rs2236624-CC, and phenotypic variability in ASD symptoms was influenced by rs3761422, rs5751876 and rs35320474. In addition, association of ADORA2A variants with anxiety was replicated for individuals with ASD. Findings point toward a possible mediating role of ADORA2A variants on phenotypic expression in ASD that need to be replicated in a larger sample.

4. Gepner B, Feron F. {{Autism: A world changing too fast for a mis-wired brain?}} {Neurosci Biobehav Rev};2009 (Jun 23)

Disorders in verbal and emotional communication and imitation, social reciprocity and higher-order cognition observed in individuals with Autism Spectrum Disorders (ASD) are presented here as phenotypic expressions of Temporo-Spatial Processing Disorders (TSPD). TSPDs include various degrees of disability in i) processing multi-sensory stimuli online, ii) associating them into meaningful and coherent patterns and iii) producing real-time sensory-motor adjustments and motor outputs. In line with this theory, we found that slowing down the speed of facial and vocal events enhanced imitative, verbal and cognitive abilities in some ASD children, particularly those with low functioning autism. We then argue that TSPDs may result from Multi-system Brain Disconnectivity-Dissynchrony (MBD), defined as an increase or decrease in functional connectivity and neuronal synchronization within/between multiple neuro-functional territories and pathways. Recent functional magnetic resonance imaging (fMRI) and electrophysiological studies supporting MBD are outlined. Finally, we review the suspected underlying neurobiological mechanisms of MBD as evidenced in neuroimaging, genetic, environmental and epigenetic studies. Overall, our TSPD/MBD approach to ASD may open new promising avenues for a better understanding of neuro-physio-psychopathology of ASD and clinical rehabilitation of people affected by these syndromes.

5. Makrythanasis P, Kapranov P, Bartoloni L, Reymond A, Deutsch S, Guigo R, Denoeud F, Drenkow J, Rossier C, Ariani F, Capra V, Excoffier L, Renieri A, Gingeras TR, Antonarakis SE. {{Variation in Novel Exons (RACEfrags) of the MECP2 Gene in Rett Syndrome Patients and Controls}}. {Hum Mutat};2009 (Jun 26)

The study of transcription using genomic tiling arrays has lead to the identification of numerous additional exons. One example is the MECP2 gene on the X chromosome; using 5’RACE and RT-PCR in human tissues and cell lines, we have found more than 70 novel exons (RACEfrags) connecting to at least one annotated exon.. We sequenced all MECP2-connected exons and flanking sequences in 3 groups: 46 patients with the Rett syndrome and without mutations in the currently annotated exons of the MECP2 and CDKL5 genes; 32 patients with the Rett syndrome and identified mutations in the MECP2 gene; 100 control individuals from the same geoethnic group. Approximately 13 kb were sequenced per sample, (2.4 Mb of DNA resequencing). A total of 75 individuals had novel rare variants (mostly private variants) but no statistically significant difference was found among the 3 groups. These results suggest that variants in the newly discovered exons may not contribute to Rett syndrome. Interestingly however, there are about twice more variants in the novel exons than in the flanking sequences (44 vs. 21 for approximately 1.3 Mb sequenced for each class of sequences, p=0.0025). Thus the evolutionary forces that shape these novel exons may be different than those of neighboring sequences. (c) 2009 Wiley-Liss, Inc.

6. Rosset DB, Santos A, Da Fonseca D, Poinso F, O’Connor K, Deruelle C. {{Do children perceive features of real and cartoon faces in the same way? Evidence from typical development and autism}}. {J Clin Exp Neuropsychol};2009 (Jun 25):1-8.

In the current study, typically developing children and children with autism spectrum disorders (ASD) were presented with a facial-feature discrimination task including both real and cartoon faces, displayed either upright or inverted. Results demonstrated that typically developing children were more accurate at discriminating facial features from upright than from inverted faces and that this effect was specific to real faces. By contrast, children with ASD failed to show such a specific pattern of performance for processing facial features displayed in real faces. Findings of the current study suggest that face type (real vs. cartoon) does not affect perceptual ability in children with ASD as it does in typically developing children.

7. Smith T, Eikeseth S, Sallows GO, Graupner TD. {{Efficacy of applied behavior analysis in autism}}. {J Pediatr};2009 (Jul);155(1):151-152; author reply 152-153.

8. Wallace GL, Silvers JA, Martin A, Kenworthy LE. {{Brief Report: Further Evidence for Inner Speech Deficits in Autism Spectrum Disorders}}. {J Autism Dev Disord};2009 (Jun 30)

Recent research indicates that individuals with autism do not effectively use inner speech during the completion of cognitive tasks. We used Articulatory Suppression (AS) to interfere with inner speech during completion of alternate items from the Tower of London (TOL). AS detrimentally affected TOL performance among typically developing (TD) adolescents (n = 25), but did not significantly diminish performance among adolescents with high functioning (IQ > 80) autism spectrum disorders (n = 28). Moreover, the TD group’s TOL performance under AS was indistinguishable from the autism group’s impaired baseline TOL performance. These findings suggest that diminished inner speech usage among individuals with high functioning autism spectrum disorders (relative to TD controls) may contribute to executive dysfunction associated with these disorders.

9. Wood JJ, Drahota A, Sze K, Van Dyke M, Decker K, Fujii C, Bahng C, Renno P, Hwang WC, Spiker M. {{Brief Report: Effects of Cognitive Behavioral Therapy on Parent-Reported Autism Symptoms in School-Age Children with High-Functioning Autism}}. {J Autism Dev Disord};2009 (Jun 27)

This pilot study tested the effect of cognitive behavioral therapy (CBT) on parent-reported autism symptoms. Nineteen children with autism spectrum disorders and an anxiety disorder (7-11 years old) were randomly assigned to 16 sessions of CBT or a waitlist condition. The CBT program emphasized in vivo exposure supported by parent training and school consultation to promote social communication and emotion regulation skills. Parents completed a standardized autism symptom checklist at baseline and posttreatment/postwaitlist and 3-month follow-up assessments. CBT outperformed the waitlist condition at posttreatment/postwaitlist on total parent-reported autism symptoms (Cohen’s d effect size = .77). Treatment gains were maintained at 3-month follow-up. Further investigation of this intervention modality with larger samples and broader outcome measures appears to be indicated.