Impaired Resolution of Perceptual Interference as an Endophenotype of ADHD

描述(由研究人员提供)：注意力缺陷多动障碍是最常见的精神健康障碍之一。最近的估计表明，它影响到2%-4%的成年人，后果包括学习和职业失败的生活史、人际关系困难和寻求刺激的行为。发展我们对ADHD的科学理解的一个关键挑战是缺乏客观的症状严重程度衡量标准。这些措施将为基础研究项目提供宝贵的工具，这些项目呼吁对ADHD受试者的核心缺陷(内表型)进行连续和定量的测量，允许测量疾病先兆(例如，遗传或环境因素)比症状检查表可能产生的更微妙的影响。我们建议研究一种心理物理程序来评估个体解决粘性干扰的能力。我们的初步数据显示，ADHD受试者在高干扰显示中在辨别目标方面存在严重缺陷，即使他们在不包含干扰刺激的同样具有挑战性的显示中表现出正常的表现。这些数据表明，ADHD受试者在知觉干扰的分辨上有很强的选择性缺陷。我们建议对特征良好的ADHD和对照人群的视觉干扰分辨率的完整性进行全面评估，样本量足够大，以仔细检查共病障碍和ADHD亚型的影响。此外，我们将使用在实验室内开发的程序，这些程序可以有选择地操纵在有人值守的位置解决干扰的程度。这些任务结合功能磁共振成像和事件相关的脑电记录，将提供对ADHD受试者干扰解决的行为和神经特征的深入分析，这可能有助于识别导致该人群在解决干扰方面严重中断的潜在认知障碍。最后，鉴于ADHD的大多数理论表明注意功能存在通道独立性缺陷，我们将检验ADHD受试者在解决听觉领域的干扰方面是否存在类似的困难。我们的初步研究将集中在基本问题上，即听觉感知空间中的哪些维度(即，空间、时间或频谱)提供了与决定视觉领域干扰的空间维度最好的模拟。

DESCRIPTION (provided by investigator): Attention Deficit Hyperactivity Disorder is amongst the most commonly diagnosed mental health disorders. Recent estimates suggest that it affects 2-4% of adults, with consequences that include life histories of academic and occupational failure, interpersonal difficulties and stimulus seeking behaviors. One key challenge for developing our scientific understanding of ADHD is a paucity of objective measures of symptom severity. Such measures would provide valuable tools for basic research programs that call for continuous and quantitative measurements of the core deficits in ADHD subjects (endophenotypes) by allowing measurements of more subtle influences of disease precursors (e.g., genetic or environmental factors) than is possible with symptom checklists. We propose to investigate a psychophysical procedure for estimating an individual's ability to resolve visaul interference. Our preliminary data reveal that ADHD subjects have a severe deficit in discriminating targets in high interference displays, even though they show normal performance with equally challenging displays that do not contain distracting stimuli. These data suggest that ADHD subjects have a strong and selective deficit in the resolution of perceptual interference. We propose a comprehensive assessment of the integrity of visual interference resolution in well characterized ADHD and control popultions, with sample sizes large enough for a careful examination of the influence of co-morbid disorders and ADHD subtypes. In addition, we will use procedures developed within our lab that enable a selective manipulation of the degree to which interference is resolved at attended locations. These tasks, in conjunction with fMRI and event-related electrical recordings of the brain, will provide an in-depth analysis of the behavioral and neural characteristics for interference resolution in ADHD subjects, which may help to identify the underlying cognitive impairments that cause the severe disruptions in resolving interference in this population. Finally, given that most theories of ADHD suggest a modality independent deficit in attentional functions, we will examine whether ADHD subjects have similar difficulties with the resolution of interference in the auditory domain. Our initial studies will focus on the basic question of which dimensions within auditory perceptual space (i.e., spatial, temporal or spectral) provide the best analog to the spatial dimension that determines interference in the visual domain.