Executive Function Development in Preschool Children

描述（由申请人提供）：执行控制是一系列源自学前时期的神经、精神和发育障碍的不良结果的重要原因或促成因素，但对幼儿执行控制的性质或发展知之甚少，也不知道如何充分衡量这个年龄段的这种能力。为了解决这个问题，我们使用了Miller和Cohen的执行控制的全面而简洁的上下文表示模型。因为这里的分析水平是神经心理测试的表现，所以经典的心理测试理论被用来将这些环境语境表征作为潜在的任务需求来运作，这些潜在的任务需求由任务之间共享的真实得分或共同因素方差来表示，即潜在的EF构念或因素。这些潜在的EF构念（标记为工作记忆、抑制和灵活移动因素）是可分离的，但高度相关；并象征着更大的环境背景的不可观察的表现，这些环境背景调用执行控制来产生规范的思想和行为。一个队列-序列，纵向设计被用来检验这个假设模型的效用。将招募一组按性别分层的3岁儿童（采用综合策略以确保多样性），每9个月进行一次执行测试，直至6-0岁，以充分模拟这一时期大脑和认知快速增长的技能发展。还将招募4个年龄错开的较小的顺序队列，随后每隔9个月随访一次，直到6-0岁。队列序列设计允许认知发展的同时纵向建模，同时直接评估重复测试管理的影响。潜在EF构念是通过专门设计用于幼儿的多个测试来先验地定义的。复杂的统计分析用于a)对比假设结构模型与从测试特定特征开发的更简单和替代模型的拟合，这些特征混淆了先前的调查，b)通过检查个体和群体在变化水平[截距]和速率[斜率]方面的差异来确定年龄的发展，以及c)表征与日常行为的动态关系。由于在临床环境中的潜在应用，个体执行测试表现的变化也将通过分层生长模型进行检查，生长混合模型将用于识别潜在的儿童群体，这些儿童的发展轨迹与同龄人不同，可能与父母对日常行为的评分有关。理解执行控制的本质和发展，以及它与日常行为的关系，最终将产生关于在许多神经发育障碍中可能受损的过程的重要信息。

DESCRIPTION (provided by applicant): Executive control is a significant cause or contributor to poor outcome in a host of neurological, psychiatric, and developmental disorders with origins in the preschool period, yet little is known about the nature or development of executive control in young children, or how to adequately measure such abilities in this age range. To address this problem, Miller and Cohen's comprehensive, yet parsimonious, context representation model of executive control was used. Because the level of analysis here is neuropsychological test performance, classic psychometric test theory was utilized to operationalize these environmental context representations as the latent task demands that are represented by the true score or common factor variance shared across tasks, i.e., latent EF constructs or factors. These latent EF constructs (labeled Working Memory, Inhibition, and Flexible Shifting factors) are separable, yet highly interrelated; and symbolize the unobservable representations of the larger environmental context that invoke executive control to produce regulated thought and behavior. A cohort-sequential, longitudinal design is used to test the utility of this postulated model. A large longitudinal cohort of 3-year-old children, stratified by sex, will be recruited (using a comprehensive strategy to assure diversity) and administered an executive test battery every 9 months through age 6-0 years, to adequately model skill development during this period of rapid brain and cognitive growth. Four smaller, sequential cohorts with staggered ages of entry also will be recruited and followed subsequently at 9 month intervals until age 6-0 years. The cohort-sequential design permits simultaneous longitudinal modeling of cognitive development, while assessing directly the impact of repeated test administration. The latent EF constructs are defined a priori by multiple tests that are designed specifically for use in young children. Sophisticated statistical analyses are used to a) contrast the fit of the hypothesized structural model to simpler and alternative models developed from test specific characteristics that have confounded previous investigations, b) determine development with age by examining individual and group differences in the level [intercept] and rates [slope] of change, and c) characterize dynamic relations to everyday behavior. Because of the potential application in clinical contexts, changes in individual executive test performance also will be examined with hierarchical growth models, and growth mixture modeling will be used to identify latent groups of children whose developmental trajectories differ from peers that may relate to parental ratings of everyday behavior. Understanding the nature and development of executive control, and its relation to everyday behavior, ultimately will yield important information regarding the processes that may be impaired in a number of neurodevelopmental disorders.