Quantitative Measurements of Cortical Excitability in Neurodevelopmental Disorder

 描述(申请人提供)：神经发育障碍，如自闭症谱系障碍(ASD)和注意缺陷多动障碍(ADHD)，其特征是基线皮质兴奋性异常，据信是由系统范围内兴奋和抑制之间的异常平衡引起的。越来越多的证据将基线皮质兴奋性与感觉系统的异常联系起来。表现为对感官刺激的过度和低反应，以及癫痫样脑电活动在包括自闭症和多动症在内的大多数神经发育障碍中的高发生率。感觉系统依赖于一套具有良好特性的机制网络，其功能直接依赖于兴奋和抑制的精确平衡。这项研究的目的是使用感觉诱发反应作为定量评估两种常见神经发育障碍ASD和ADHD的基础皮质兴奋性的方法。这些测量将通过稳态视觉和听觉诱发电位进行。电生理学测量的感觉反应模式将与通过特征明确的父母问卷和考官管理的表现评估测量的行为高/高敏感模式进行比较。这些测量将从40名ASD儿童、40名ADHD儿童和40名匹配的对照组儿童中获得。该项目的直接目标是确定感觉诱发电位的特定模式是否与受干扰的感觉处理的行为指标有关。这项建议的长期目标是开发敏感和客观的皮质兴奋性测量方法，用于神经发育障碍的分类。检测和量化婴儿期和儿童期皮质兴奋性潜在变化的能力将在常见神经发育障碍的诊断、分类和治疗管理中具有重要价值。目前的建议是实现这一目的的基本步骤，这种方法与NIMH战略计划一致，该战略计划旨在开发基于可观察行为和神经生物学测量的精神病理学分类的新方法。

 DESCRIPTION (provided by applicant): Neurodevelopmental disorders, such as autism spectrum disorder (ASD) and attention deficit hyperactivity disorder (ADHD), are characterized by abnormalities in baseline cortical excitability that are believed to be caused by an abnormal, system-wide balance between excitation and inhibition. Mounting evidence has linked baseline cortical excitability to abnormalities in the sensory systems. as manifested by both over- and hypo- reactivity to sensory stimuli and by the high prevalence of epileptiform EEG activity in the majority of neurodevelopmental disorders including ASD and ADHD. Sensory systems rely on a set of well-characterized network of mechanisms whose functioning directly depends on a precise balancing of excitation and inhibition. The aim of this investigation is to use sensory evoked responses as a means to quantitatively assess baseline cortical excitability in two common neurodevelopmental disorders, ASD and ADHD. These measurements will be made via Steady-State Visual and Auditory Evoked Potentials. Patterns sensory responses measured electrophysiologically will be compared to patterns of behavioral hyper/hyposensitivity measured via a well- characterized parental questionnaire and examiner-administered performance evaluations. These measurements will be obtained from 40 children with ASD, 40 children with ADHD and 40 matched controls. The immediate goal of the project is to determine whether specific patterns of sensory evoked potentials are associated with behavioral indices of disturbed sensory processing. The long-term goal of this proposal is to develop sensitive and objective measures of cortical excitability for use in classifying neurodevelopmental disorders. An ability to detect and quantify underlying alterations in cortical excitability in infancy and ealy childhood would be of significant value in the diagnosis, classification and treatment management of common neurodevelopmental disorders. The present proposal is a fundamental step toward the achievement of this purpose and this approach is consistent with the NIMH Strategic Plan for the development of new ways of classifying psychopathology based on dimensions of observable behavior and neurobiological measures.