Análise de genes envolvidos na neurotransmissão, formação e manutenção sináptica em indivíduos com transtornos do espectro do Autismo

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Short-Term Effects of the Use of Non-Rigid Tools for Postural Control by Adults with Intellectual Disabilities

We tested the short-term effects of a nonrigid tool, identified as an "anchor system" (e.g., ropes attached to varying weights resting on the floor), on the postural stabilization of blindfolded adults with and without intellectual disabilities (ID). Participants held a pair of anchors one in each hand, under three weight conditions (250 g, 500 g and 1,000 g), while they performed a restricted balance task (standing for 30 s on a balance beam placed on top of a force platform). These conditions were called anchor practice trials. Before and after the practice trials, a condition without anchors was tested. Control practice groups, who practiced blocks of trials without anchors, included individuals with and without ID. The anchor system improved subjects' balance during the standing task, for both groups. For the control groups, the performance of successive trials in the condition without the anchor system showed no improvement in postural stability. The individuals with intellectual disability, as well as their peers without ID, used the haptic cues of nonrigid tools (i.e., the anchor system) to stabilize their posture, and the short-term stabilizing effects appeared to result from their previous use of the anchor system.

Speech perception and cortical auditory evoked potentials in cochlear implant users with auditory neuropathy spectrum disorders

Objective: To characterize the PI component of long latency auditory evoked potentials (LLAEPs) in cochlear implant users with auditory neuropathy spectrum disorder (ANSD) and determine firstly whether they correlate with speech perception performance and secondly whether they correlate with other variables related to cochlear implant use. Methods: This study was conducted at the Center for Audiological Research at the University of Sao Paulo. The sample included 14 pediatric (4-11 years of age) cochlear implant users with ANSD, of both sexes, with profound prelingual hearing loss. Patients with hypoplasia or agenesis of the auditory nerve were excluded from the study. LLAEPs produced in response to speech stimuli were recorded using a Smart EP USB Jr. system. The subjects' speech perception was evaluated using tests 5 and 6 of the Glendonald Auditory Screening Procedure (GASP). Results: The P-1 component was detected in 12/14 (85.7%) children with ANSD. Latency of the P-1 component correlated with duration of sensorial hearing deprivation (*p = 0.007, r = 0.7278), but not with duration of cochlear implant use. An analysis of groups assigned according to GASP performance (k-means clustering) revealed that aspects of prior central auditory system development reflected in the P-1 component are related to behavioral auditory skills. Conclusions: In children with ANSD using cochlear implants, the P-1 component can serve as a marker of central auditory cortical development and a predictor of the implanted child's speech perception performance. (c) 2012 Elsevier Ireland Ltd. All rights reserved.

Questionário sobre dificuldades comunicativas percebidas por pais de crianças do espectro do autismo

OBJETIVO: Elaborar um questionário para o levantamento de dificuldades comunicativas percebidas por pais e/ou cuidadores de crianças do espectro do autismo em relação a seus filhos. MÉTODOS: Os aspectos específicos abordados no questionário foram identificados a partir da literatura e da experiência clínica das autoras em dois serviços especializados. As questões foram organizadas segundo diferentes domínios e as respostas registradas numa escala tipo Likert. Foi realizado um estudo piloto com 40 pais, 20 pais de crianças do espectro do autismo e 20 pais de crianças sem queixas de linguagem, como forma de verificar a aplicabilidade do questionário construído e sua utilidade na identificação de dificuldades específicas da população alvo. Foi calculado o nível de concordância das questões e os resultados dos grupos foram comparados entre si (teste t Student). RESULTADOS: O questionário foi desenvolvido de maneira a abranger aspectos fundamentais para o relacionamento interpessoal, tanto no âmbito comunicativo quanto social. Foi dividido em 24 questões fechadas que abrangem quatro domínios; e uma questão aberta, com espaço para que os pais relatassem algo relevante e que não tenha sido perguntado. O estudo possibilitou testar a compreensão do instrumento e a análise estatística indicou que 19 questões apresentaram diferença. CONCLUSÃO: O questionário elaborado identificou diferenças na percepção e atitude de pais de crianças do espectro do autismo e de crianças sem queixa de linguagem, em relação às dificuldades de comunicação com seus filhos. Dessa forma, mostrou-se útil para o levantamento dessas dificuldades em um grupo maior de indivíduos.

Functional Communication Profile - Revised: uma proposta de caracterização objetiva de crianças e adolescentes do espectro do autismo

OBJETIVO: Caracterizar objetivamente as alterações de crianças e adolescentes incluídos no espectro do autismo de acordo com o grau de severidade definido a partir das respostas ao Functional Communication Profile - Revised (FCP-R). MÉTODOS: Foram selecionadas 50 crianças (idade média 7 anos e 11 meses) com diagnósticos no espectro do autismo que foram avaliados segundo os critérios do FCP-R. As respostas obtidas foram pontuadas e classificadas de acordo com a severidade e realizada análise estatística pertinente. RESULTADOS: A caracterização dessa população evidenciou dados concordantes com a literatura, mostrando prejuízos nas áreas de linguagem (expressiva e receptiva), comportamento e pragmática, principalmente. Os indivíduos que não possuem habilidades verbais evidenciaram, ainda, alterações referentes aos domínios fala e fluência. CONCLUSÃO: O FCP-R foi sensível para caracterizar a população estudada, mostrando-se ainda mais eficaz para a avaliação individualizada.

Investigating the role of Copy Number Variants in Specific Language Impairment and identification of new candidate genes

Specific language impairment (SLI) is a complex neurodevelopmental disorder defined as an unexpected failure to develop normal language abilities for no obvious reason. Copy number variants (CNVs) are an important source of variation in the susceptibility to neuropsychiatric disorders. Therefore, a CNV study within SLI families was performed to investigate the role of structural variants in SLI. Among the identified CNVs, we focused on CNVs on chromosome 15q11-q13, recurrently observed in neuropsychiatric conditions, and a homozygous exonic microdeletion in ZNF277. Since this microdeletion falls within the AUTS1 locus, a region linked to autism spectrum disorders (ASD), we investigated a potential role of ZNF277 in SLI and ASD. Frequency data and expression analysis of the ZNF277 microdeletion suggested that this variant may contribute to the risk of language impairments in a complex manner, that is independent of the autism risk previously described in this region. Moreover, we identified an affected individual with a dihydropyrimidine dehydrogenase (DPD) deficiency, caused by compound heterozygosity of two deleterious variants in the gene DPYD. Since DPYD represents a good candidate gene for both SLI and ASD, we investigated its involvement in the susceptibility to these two disorders, focusing on the splicing variant rs3918290, the most common mutation in the DPD deficiency. We observed a higher frequency of rs3918290 in SLI cases (1.2%), compared to controls (~0.6%), while no difference was observed in a large ASD cohort. DPYD mutation screening in 4 SLI and 7 ASD families carrying the splicing variant identified six known missense changes and a novel variant in the promoter region. These data suggest that the combined effect of the mutations identified in affected individuals may lead to an altered DPD activity and that rare variants in DPYD might contribute to a minority of cases, in conjunction with other genetic or non-genetic factors.

Human Preferences for Symmetry: Subjective Experience, Cognitive Conflict and Cortical Brain Activity

This study examines the links between human perceptions, cognitive biases and neural processing of symmetrical stimuli. While preferences for symmetry have largely been examined in the context of disorders such as obsessive-compulsive disorder and autism spectrum disorders, we examine various these phenomena in non-clinical subjects and suggest that such preferences are distributed throughout the typical population as part of our cognitive and neural architecture. In Experiment 1, 82 young adults reported on the frequency of their obsessive-compulsive spectrum behaviors. Subjects also performed an emotional Stroop or variant of an Implicit Association Task (the OC-CIT) developed to assess cognitive biases for symmetry. Data not only reveal that subjects evidence a cognitive conflict when asked to match images of positive affect with asymmetrical stimuli, and disgust with symmetry, but also that their slowed reaction times when asked to do so were predicted by reports of OC behavior, particularly checking behavior. In Experiment 2, 26 participants were administered an oddball Event-Related Potential task specifically designed to assess sensitivity to symmetry as well as the OC-CIT. These data revealed that reaction times on the OC-CIT were strongly predicted by frontal electrode sites indicating faster processing of an asymmetrical stimulus (unparallel lines) relative to a symmetrical stimulus (parallel lines). The results point to an overall cognitive bias linking disgust with asymmetry and suggest that such cognitive biases are reflected in neural responses to symmetrical/asymmetrical stimuli.