Pubmed du 29/01/09

Pubmed du jour

2009-01-29 12:03:50

1. Gilbert SJ, Meuwese JD, Towgood KJ, Frith CD, Burgess PW. {{Abnormal functional specialization within medial prefrontal cortex in high-functioning autism: a multi-voxel similarity analysis}}. {Brain};2009 (Jan 27)

Multi-voxel pattern analyses have proved successful in ‘decoding’ mental states from fMRI data, but have not been used to examine brain differences associated with atypical populations. We investigated a group of 16 (14 males) high-functioning participants with autism spectrum disorder (ASD) and 16 non-autistic control participants (12 males) performing two tasks (spatial/verbal) previously shown to activate medial rostral prefrontal cortex (mrPFC). Each task manipulated: (i) attention towards perceptual versus self-generated information and (ii) reflection on another person’s mental state (‘mentalizing’versus ‘non-mentalizing’) in a 2 x 2 design. Behavioral performance and group-level fMRI results were similar between groups. However, multi-voxel similarity analyses revealed strong differences. In control participants, the spatial distribution of activity generalized significantly between task contexts (spatial/verbal) when examining the same function (attention/mentalizing) but not when comparing different functions. This pattern was disrupted in the ASD group, indicating abnormal functional specialization within mrPFC, and demonstrating the applicability of multi-voxel pattern analysis to investigations of atypical populations.

2. Kawatani M, Nakai A, Mayumi M, Hiratani M. {{[Retrospective analysis of pervasive developmental disorder patients initially diagnosed with attention deficit/hyperactivity disorder]}}. {No To Hattatsu};2009 (Jan);41(1):11-16.

We retrospectively analyzed 66 patients with pervasive developmental disorder (PDD) whose respective diagnoses had been changed from attention deficit/hyperactivity disorder (AD/HD) and compared their clinical characteristics with those in patients whose diagnoses was not altered (n = 135). Of 52 patients, 41 (79%) had language delay or hyperactivity at initial examination. Of the 47 patients treated with methylphenidate, 41 patients (87%) responded favorably. The patients with altered diagnoses were categorized into three groups with inappropriate diagnoses (n = 32), amended diagnoses (n = 6), and dual diagnoses (n = 28). Consequently, some patients increasingly showed PDD characteristics concomitantly with age; other patients had justified dual diagnoses with PDD and AD/HD. The total points for peculiar behavioral history were significantly higher in patients with altered diagnoses than in those with unaltered diagnoses (5.4 +/- 3.7 vs. 2.6 +/- 2.6, p < 0.001). In particular, the points for language delay, indifference, and persistence were significantly more positive in patients with altered diagnoses. Results suggest that close evaluation of an individual’s behavioral history might suggest a differential diagnosis between PDD and AD/HD.

3. Kenworthy L, Black DO, Harrison B, Della Rosa A, Wallace GL. {{Are Executive Control Functions Related to Autism Symptoms in High-Functioning Children?}} {Child Neuropsychol};2009 (Jan 27):1-16.

Background: Linking autism symptoms to cognitive abilities can expand phenotypic descriptions and facilitate investigations into the etiology and treatment of this multiplex disorder. Executive dysfunction is one of several potential cognitive phenotypes in autism. Method: Archival clinical data on 89 children diagnosed with Autism Spectrum Disorders and administered a large neuropsychological battery were evaluated for relationships between executive functioning and autism symptoms. Results: Significant relationships between both laboratory tasks and behavior rating scales of executive functions and autism symptoms were identified. Multiple regression analyses revealed that measures of semantic fluency, divided auditory attention, and behavioral regulation were significantly correlated with autism symptoms, even after accounting for the variance from correlated « nuisance variables, » such as vocabulary and age. Conclusions: Executive dysfunction is related to all three clusters of behavioral symptoms in Autism Spectrum Disorders.

4. Turk J, Bax M, Williams C, Amin P, Eriksson M, Gillberg C. {{Autism spectrum disorder in children with and without epilepsy: impact on social functioning and communication}}. {Acta Paediatr};2009 (Jan 27)

Aim: To compare developmental and psychological functioning in two groups of children with autism spectrum disorder (asd), one with epilepsy and one without. Methods: Sixty 7-17-year-old children in each group were recruited through a range of services in order to screen as representative a sample as possible. Parents were interviewed using the diagnostic interview for social and communication disorders (DISCO-11), and children were clinically examined and their medical histories assessed. Results: The asd and epilepsy (asd+e) group demonstrated a substantially more even gender ratio, with a greater proportion of girls. They were more likely to have received later asd diagnoses and additional medical diagnoses. They also showed more motor difficulties, developmental delays and challenging behaviours, but were no more likely to be aloof and passive. The asd-only group experienced more abnormal fascinations with objects and used brief glances as a means of eye contact more than the asd+e group. Conclusion: Results support important between-group differences with diagnostic and therapeutic implications. asds often present atypically in children with seizures. However, both groups showed widely varying social and linguistic presentations.

5. Watanabe S, Yamakura S, Hirano K, Okumura Y, Aiba H. {{[A case of infantile autism with pediatric Wernicke’s encephalopathy due to severe eating disorder]}}. {No To Hattatsu};2009 (Jan);41(1):43-46.

Wernicke’s encephalopathy (WE) or thiamine deficiency is fatal if left untreated. We report a case of a 3-year-old boy with infantile autism and a severe eating disorder who developed WE after 3 weeks of starvation without thiamine supplementation. The eating disorder started when he entered preschool. He presented with unconsciousness and a cluster of seizures. Cranial magnetic resonance imaging (MRI) showed high-intensity signal changes in the basal ganglia on T2-weighted images and fluid-attenuated inversion recovery (FLAIR). Treatment with high-dose intravenous thiamine was effective. Pediatric patients with WE tends to show no typical symptoms or brain lesions on MRI as seen in adult WE patients typically along alcoholics. Brain lesions similar to those in hypoxia or mitochondrial diseases such as Leigh’s encephalopathy, are observed in patients with pediatric WE, and this makes diagnosis difficult. WE should be considered when patients with severe eating disorders present with unconsciousness and/or frequent seizures, and show basal ganglia lesions on MRI, differential diagnosis should include WE.