Spatial contrast sensitivity in adolescents with autism spectrum disorders

Adolescents with autism spectrum disorders (ASD) and typically developing (TD) controls underwent a rigorous psychophysical assessment that measured contrast sensitivity to seven spatial frequencies (0.5-20 cycles/degree). A contrast sensitivity function (CSF) was then fitted for each participant, from which four measures were obtained: visual acuity, peak spatial frequency, peak contrast sensitivity, and contrast sensitivity at a low spatial frequency. There were no group differences on any of the four CSF measures, indicating no differential spatial frequency processing in ASD. Although it has been suggested that detail-oriented visual perception in individuals with ASD may be a result of differential sensitivities to low versus high spatial frequencies, the current study finds no evidence to support this hypothesis

The integration of occlusion and disparity information for judging depth in autism spectrum disorder

In autism spectrum disorder (ASD), atypical integration of visual depth cues may be due to flattened perceptual priors or selective fusion. The current study attempts to disentangle these explanations by psychophysically assessing within-modality integration of ordinal (occlusion) and metric (disparity) depth cues while accounting for sensitivity to stereoscopic information. Participants included 22 individuals with ASD and 23 typically developing matched controls. Although adults with ASD were found to have significantly poorer stereoacuity, they were still able to automatically integrate conflicting depth cues, lending support to the idea that priors are intact in ASD. However, dissimilarities in response speed variability between the ASD and TD groups suggests that there may be differences in the perceptual decision-making aspect of the task

Brief Report: Visual Acuity in Children with Autism Spectrum Disorders

Recently, there has been heightened interest in suggestions of enhanced visual acuity in autism spectrum disorders (ASD) which was sparked by evidence that was later accepted to be methodologically flawed. However, a recent study that claimed children with ASD have enhanced visual acuity (Brosnan et al. in J Autism Dev Disord 42:2491–2497, 2012) repeated a critical methodological flaw by using an inappropriate viewing distance fora computerised acuity test, placing the findings in doubt. We examined visual acuity in 31 children with ASD and 33controls using the 2 m 2000 Series Revised Early Treatment Diabetic Retinopathy Study chart placed at twice the conventional distance to better evaluate possible enhanced acuity. Children with ASD did not demonstrate superior acuity. The current findings strengthen the argument that reports of enhanced acuity in ASD are due to methodological flaws and challenges the reported association between visual acuity and systemising type behaviours

Measurement of the branching fraction for the cabibbo-suppressed decay K*-(892)

This Letter presents a measurement of the branching fraction for the Cabibbo-suppressed decay -K*-(892) with use of data obtained with the Mark-II detector at SPEAR. Eleven events containing a K*(892) in coincidence with a muon or an electron of opposite charge were found in data which span the center-of-mass energy region 4.

O uso de antipsicóticos em pacientes com diagnóstico de demência The use of antipsychotics in patients with dementia

OBJETIVO: Revisar sistematicamente as evidências que sustentam o uso de antipsicóticos no tratamento dos sintomas comportamentais e psicológicos em pacientes com demência, assim como rever as controvérsias e desvantagens dessa prescrição, tendo em vista, por um lado, a elevada prevalência destas manifestações no curso clínico das demências e, por outro, a maior susceptibilidade do idoso aos eventos adversos desses medicamentos. MÉTODO: Revisão sistemática da literatura sobre o uso de antipsicóticos típicos e atípicos em pacientes portadores de síndromes demenciais. As bases de dados usadas para este fim foram o PubMed/Medline, Embase e SciELO. A busca por trabalhos se limitou aos anos de 1986 a 2007, selecionando-se ensaios clínicos randomizados e metanálises da literatura. RESULTADOS: Há evidências a partir de ensaios randomizados, duplamente encobertos, controlados por placebo, de que os antipsicóticos típicos e atípicos são eficazes no tratamento dos sintomas comportamentais que ocorrem nas síndromes demenciais, especialmente os quadros psicóticos e alterações do comportamento motor. Entretanto, o uso destas medicações está associado a eventos adversos importantes. Embora os antipsicóticos atípicos estejam menos associados aos efeitos colaterais extrapiramidais, comuns entre os neurolépticos de primeira geração, podem aumentar a incidência de eventos cerebrovasculares e do risco de morte, sobretudo em pacientes vulneráveis. CONCLUSÃO: Os antipsicóticos devem ser usados com cautela nos pacientes com demência, buscando otimizar o regime de dosagem e duração do tratamento, e avaliando-se individualmente a relação risco-benefício.<br>OBJECTIVE: The objective of the present study is to systematically review the supporting evidence for the use of antipsychotics in the treatment of behavioral and psychological symptoms in patients with dementia, as well as the controversies and limitations of this prescription. We discuss the available evidence in the light of the high prevalence of behavioral and psychological symptoms of dementia in this population, along with the greater susceptibility of elderly patients to adverse events. METHOD: Systematic literature review of the use of typical and atypical antipsychotics in patients with dementia was carried out in the databases PubMed/Medline, Embase and SciELO. The search was limited to clinical trials and meta-analysis of the literature published from 1986 to 2007. RESULTS: Evidence drawn from randomized, double-blind, placebo controlled trials support the use of both typical and atypical antipsychotics in the treatment of behavioral symptoms of dementia, especially psychotic symptoms and abnormal psychomotor activity. Nevertheless, the use of these drugs in demented patients is not devoid of important adverse events. Although the induction of extrapiramidal symptoms is not as frequent or severe with atypical antipsychotics as it is with first-generation neuroleptics, the former drugs may particularly increase the risk of cerebrovascular events and death. CONCLUSION: Although effective, antipsychotic drugs must be prescribed cautiously in patients with dementia. Dose regimens, duration of treatment and a cautious assessment of risk-benefit must be established for each patient