Dynamic Mechanisms of Cognitive Control and Reorganization of Brain Networks

项目摘要 认知控制是指一个人完成相关日常任务和追求目标的一般能力。 在分心的情况下实现目标。这种对信息处理的灵活控制与 前额叶皮层（PFC），被发现通过增强任务相关过程来调节大脑活动， 下调任务无关区域的进程。全氟化学品的不同区域构成了 与认知控制相关的大脑网络：扣带-鳃盖（CO）网络，与 保持警觉，以及额顶叶（FP）网络，与即时调整有关， 行为虽然这些网络之间的区别已经得到了很好的研究，但目前还不清楚这些网络如何 在不断变化的任务需求中进行交互以支持性能。使用任务转换模式， 融合脑成像方法，该提案旨在研究认知的动态机制， 通过分析大脑网络的相互作用及其对行为的具体影响来控制。具体而言，目标1将 检查大规模的全脑重组和变化的额顶叶（FP）和扣带盖（CO） 网络交互作为认知控制的动态实现机制。更大的网络 由认知控制网络之间的更大连接性驱动的交互， 要求的情况（即转换试验）被假设为促进信息的传递和处理， 实现相关目标。第一个目标将探索这样的重新配置是否会随着任务的需要而迅速发生 在切换范式中从一个试验到另一个试验的变化，需要迅速将注意力控制从一个 任务给另一个。功能性磁共振成像（fMRI），一种使用 血液流动的相关变化，将用于提取大脑区域之间相关活动的测量 和网络。目标2将涉及CO和FP认知控制网络中的扰动活动，以确定 特定网络中断对认知控制的不同影响，模拟神经系统疾病， 涉及相连但未受损的大脑区域的变化。经颅磁刺激（TMS） TMS是一种非侵入性技术，可以暂时抑制大脑活动， 对大脑功能或行为没有长期影响的目标区域。了解了 认知控制的动力学--无论是在适应性任务水平上还是在网络中断之后， PFC中断对创伤性脑损伤、中风和抑郁症患者的广泛影响。识别 大脑机制对表现的重要性，以及急性损伤改变这些机制的方式， 这些机制将为生物标志物提供信息，这些生物标志物可以帮助开发诊断工具和治疗途径。

Project Summary Cognitive control refers to the general ability that allows one to complete relevant everyday tasks and pursue demanding goals in the face of distraction. This flexible control of information processing is linked to the prefrontal cortex (PFC), which is found to modulate brain activity by enhancing task-relevant processes and down-regulating processes in task-irrelevant regions. Different regions of the PFC form critical elements of brain networks that have been related to cognitive control: the cingulo-opercular (CO) network, linked to maintaining alertness, and the fronto-parietal (FP) network, linked to moment-to-moment adjustments of behavior. While the distinction between these networks is well-studied, it is unclear how these networks interact to support performance in the midst of changing task demands. Using a task-switching paradigm and converging brain imaging methods, this proposal aims to investigate the dynamic mechanisms of cognitive control by analyzing brain network interactions and its specific effects on behavior. Specifically, Aim 1 will examine large-scale whole-brain reorganization and changing fronto-parietal (FP) and cingulo-opercular (CO) network interactions as mechanisms for dynamic implementation of cognitive control. Greater network interactions driven by greater connectivity between cognitive control networks in response to cognitively demanding situations (i.e. switch trials) is hypothesized to facilitate transfer and processing of information to achieve relevant goals. This first aim will probe whether such reconfiguration occurs rapidly as task demands change from trial to trial in a switching paradigm that requires rapid redirection of attentional control from one task to another. Functional magnetic resonance imaging (fMRI), a method that estimates neural activity using associated changes in blood flow, will be used to extract measures of correlated activity between brain regions and networks. Aim 2 will involve perturbing activity in the CO & FP cognitive control networks to determine the differential effects of specific network disruption on cognitive control, simulating neurological disorders that involve changes in connected, but undamaged brain regions. Transcranial magnetic stimulation (TMS) will be used to for this second aim; TMS is a non-invasive technique that can temporarily suppress brain activity over a targeted region without long-term consequences on brain function or behavior. Gaining insight into the dynamics of cognitive control—both at the adaptive task level and following network disruption, can shed light on the broad effects of PFC disruption in patients with traumatic brain injury, stroke, and depression. Identifying the brain mechanisms important for performance, and the ways in which acute damage modifies these mechanisms will inform biomarkers that can aid in developing diagnostic tools and avenues for treatment.