Response Variability in Children with ADHD

描述(由申请人提供)：患有注意力缺陷多动障碍(ADHD)的儿童有许多神经心理功能障碍，包括反应抑制、工作记忆和注意力。反应变异性是一种持续揭示组间差异的神经心理学结果指标。然而，直到最近，反应变异性的差异一直被报告为辅助发现或被视为分析中的麻烦。本研究的具体目的是1)检测ADHD患者跨神经心理任务的反应变异性，以了解这一特定缺陷的广度，并了解反应变异性与其他神经心理结果指标之间的关系；2)评估反应变异性缺陷是否仅针对两种最常见的ADHD亚型中的一种或两种(即合并型[CT]和主要的注意力不集中型[PIT])；3)确定ADHD患者的反应变异性是否受到药物或各种环境操作(例如奖励)的影响；以及4)了解反应变异性的神经心理学指标与变量表现的自然情况之间的关系。45名患有ADHD-CT的儿童(7-11岁)、45名ADHD-PIT儿童和45名正常对照将被招募，以检查广泛的神经心理测试中的反应变异性。任务参数，如事故率、刺激的显著程度和操作奖赏的存在，将在每项测试中进行修改，以确定ADHD儿童在何种条件下表现出反应变异性。此外，所有患有ADHD的儿童将参加一项安慰剂对照的随机用药试验，用一种精神刺激性药物来评估药物对反应变异性的影响。利用反应时间数据的非高斯分布和快速傅立叶变换的高级分析方法将被用于对ADHD和正常对照组的RT模式进行详细分析。此外，还将考察任务参数操作和药物对反应变异性的影响。最后，将研究神经心理测试中的反应变异性与各种真实世界模拟情景中的反应变异性之间的关系，以评估这些缺陷的生态有效性。

DESCRIPTION (provided by applicant): Children with Attention Deficit Hyperactivity Disorder (ADHD) have numerous areas of neuropsychological dysfunction including response inhibition, working memory, and attention. One neuropsychological outcome measure that consistently reveals between-group differences is response variability. However, until recently, differences in response variability have been reported as an ancillary finding or viewed as a nuisance in the analyses. The specific aims of the present study are to 1) Examine response variability in ADHD patients across neuropsychological tasks to understand the breadth of this specific deficit and to understand the relation between response variability and other neuropsychological outcome measures; 2) Assess whether response variability deficits are specific to either or both of the two most prevalent ADHD subtypes (i.e., Combined Type [CT] and Predominantly Inattentive Type [PIT]); 3) Determine whether response variability in ADHD patients is affected by either medication or a variety of environmental manipulations (e.g., reward); and 4) Understand the relationship between neuropsychological measures of response variability and naturalistic instances of variable performance. Forty-five children (aged 7-11) with ADHD-CT, 45 children with ADHD-PIT, and 45 normal controls will be recruited to examine response variability across a wide range of neuropsychological tests. Task parameters such as event rate, stimulus saliency, and the presence of operant reward will be modified on each test to determine the conditions under which response variability is manifested in children with ADHD. In addition, all children with ADHD will participate in a placebo-controlled, randomized medication trial with a psychostimulant medication to assess the effects of medication on response variability. Advanced analytic methods utilizing non-Gaussian distributions and fast Fourier Transforms of the reaction time data will be used to conduct detailed analyses of RT patterns across the ADHD and normal control groups. Further, the effects of task parametric manipulations and medication on response variability will be examined. Finally, relations between response variability on neuropsychological tests and response variability in a variety of real-world analog situations will be examined to evaluate the ecological validity of these deficits.