Development of executive function

执行功能(EF；即有意识地控制思维和行动的心理过程)在儿童时期经历了相当大的发展，现在有证据表明，EF的发展在一定程度上取决于表示日益复杂的规则集的能力--儿童首先获得表示单个规则的能力，然后是一对规则，然后是允许他们从不兼容的规则对中进行选择的分级规则系统(Zelazo等人，2003)。虽然前额叶皮质(PFC)在EF中起着重要作用，但关于PFC的特定发育变化与儿童EF的特定变化之间的关系还知之甚少。目前的建议描述了一种新的研究路线，旨在评估EF发育的神经关联，特别是PFC的作用。假设规则使用的发展变化模式反映了PFC内特定区域的不同发展速度--从眼眶前额叶皮质(当刺激-奖赏关联需要颠倒时的单一反应规则)，到腹外侧和背外侧PFC(条件规则集)，再到吻侧PFC(在任务集中进行选择的更高顺序规则)。主要的行为测量将是维度变化卡片分类的版本(DCCS；Zelazo等人，2003)。将使用两种主要的神经功能测量方法，尽可能重叠评估：事件相关功能磁共振成像(FMRI)和密集阵列(128通道)EEG/ERP。EEG/ERP具有毫秒级的时间分辨率，是捕捉神经处理时间过程的理想选择。这项研究计划的结果有可能阐明与年龄相关的PFC变化的功能意义，并将解决经验对儿童早期EF发展的影响。从长远来看，这些结果将为跨越行为、认知/情绪和神经分析层面的EF提供详细、综合的描述基础。其中一个应用将是为患有与EF相关的障碍(例如，ADHD、自闭症、CD、PKU)的儿童开发干预措施。

Executive function (EF; i.e., psychological processes involved in the conscious control of thought and action) undergoes considerable development during childhood, and there is now evidence that the development of EF depends, in part, on a growing ability to represent increasingly complex sets of rules--children first acquire the ability to represent a single rule, then a pair of rules, and then a hierarchical system of rules that allows them to select among incompatible pairs of rules (Zelazo et al., 2003). Although it is clear that prefrontal cortex (PFC) plays an important role in EF, relatively little is known about how specific developmental changes in PFC are related to specific changes in children's EF. The current proposal describes a new line of research that aims to assess the neural correlates of EF development, focusing in particular on the role of PFC. It is hypothesized that the pattern of developmental changes in rule use reflects the different rates of development of specific regions within PFC--from orbitofrontal cortex (single rules for responding when stimulus-reward associations need to be reversed), to ventrolateral and dorsolateral PFC (sets of conditional rules), to rostrolateral PFC (higher-order rules for selecting among task sets). Primary behavioral measures will be versions of the dimensional change card sort (DCCS; Zelazo et al., 2003). Two main measures of neural function will be used, with overlapping assessments when possible: event-related functional Magnetic Resonance Imaging (fMRI) and dense-array (128-channel) EEG/ERP. EEG/ERP has millisecond temporal resolution and is ideal for capturing the time course of neural processing. The results of this research program have the potential to shed light on the functional significance of age-related changes in PFC, and they will also address the effect of experience on EF development during early childhood. In the long-term, the results will provide the foundation of a detailed, integrative account of EF that spans behavioral, cognitive/emotional, and neural levels of analysis. One application will be to develop interventions for children with disorders related to EF (e.g., ADHD, autism, CD, PKU).