Prefrontal network dynamics and top-down control of spatial representation

前额网络动力学和空间表征的自上而下控制

• 批准号: 8437283
• 负责人: MATTHEW V CHAFEE
• 金额: $ 26.64万
• 依托单位: UNIVERSITY OF MINNESOTA
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-06-20 至 2015-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8437283
• 关键词: Area; Behavioral; Behavioral Paradigm; Biological Neural Networks; Brain; Categories; Cerebral cortex; Code; Cognition; Cognitive; Event; Experimental Designs; Goals; Grouping; Human; Individual; Joints; Knowledge; Left; Measurable; Measures; Mediating; Monkeys; Morphologic artifacts; Nature; Network-based; Neurons; Output; Parietal; Parietal Lobe; Pattern; Performance; Persons; Physiological; Physiological Processes; Play; Positioning Attribute; Prefrontal Cortex; Process; Property; Recruitment Activity; Relative (related person); Research; Role; Schizophrenia; Sensory Process; Signal Transduction; Stimulus; Stroke; System; Testing; Time; Training; Ursidae Family; Visual; Work; abstracting; base; cognitive function; design; executive function; flexibility; human disease; member; neuromechanism; nonhuman primate; relating to nervous system; research study; response; spatial relationship; success; visual receptive field; visual stimulus

Abstract The human brain processes sensory input flexibly to extract the most useful information and generate the most advantageous response given current behavioral strategies and goals. Computational flexibility of this type is often referred to as executive control, particularly when it involves the brain selecting to implement one cognitive process over another in order to determine the best course of action within a given context. We have a limited understanding of how executive control, as such, is mediated by physiological events in cortical neurons. To increase our knowledge of the cellular basis of executive control, I propose to simultaneously record the electrical activity of ensembles of 20-30 individually isolated neurons in prefrontal cortex (area 46) and in posterior parietal cortex (area 7a) of monkeys as they perform a task requiring them to exert executive control over spatial cognition. Specifically, monkeys will assign visual stimuli to alternative spatial categories according to a variable grouping criterion (rule) that we instruct and change on a trial-by-trial basis. In this task, we present a line that serves as a category boundary, and define spatial categories as groups of spatial positions that bear the same spatial relationship to the line - such that, for example, all points to the left of the line comprise one category, and all points to the right another. By shifting and rotating the boundary, we require the brain to flexibly reassign a fixed set of spatial positions to alternative spatial categories in a rule- dependent manner, and this requires the brain to exert executive control over spatial categorization as a cognitive and physiological process. Our objective is to discover how executive control over spatial categorization is implemented at a cellular level, by measuring rule-dependent changes in distributed neural representations of the spatial category to which the brain has assigned a stimulus under a given rule. We will test the hypothesis that rule-dependent changes in category representation will emerge first and be strongest in prefrontal cortex. This will support our hypothesis that prefrontal cortex sits above parietal cortex in a hierarchy of areas mediating executive control over cognitive processing in distributed cortical systems, and provide some of the first detail about the neural mechanisms by which this control is implemented at a cellular level.

抽象的 人脑处理感官输入，以提取最有用的信息并生成 鉴于当前的行为策略和目标，最有利的反应。计算灵活性 类型通常称为执行控制，尤其是当它涉及大脑选择实施一个 认知过程在另一个方面，以确定给定上下文中最佳的行动方案。我们有 对执行控制的有限理解是由皮质中的生理事件介导的 神经元。为了增加我们对执行控制的细胞基础的了解，我建议同时 记录前额叶皮层中20-30个单独隔离神经元的集合的电活动（区域46） 在猴子的后顶叶皮层（区域7a）中 控制空间认知。具体而言，猴子会将视觉刺激分配给替代空间类别 根据可变分组标准（规则），我们通过试用基础进行指导和更改。在这个 任务，我们提出一条线，该行是类别边界，并将空间类别定义为空间组 与线路有相同空间关系的位置 - 例如，所有指向的所有点 行分为一个类别，所有人都指向另一个类别。通过移动和旋转边界，我们 要求大脑在规则中灵活地将固定的空间位置重新分配到替代空间类别 依赖方式，这要求大脑对空间分类的行政控制作为一个 认知和生理过程。我们的目标是发现高管控制空间 分类是通过测量分布式神经的规则依赖性变化来在细胞级别实现的 大脑根据给定规则分配刺激的空间类别的表示。我们将 检验以下假设，即规则依赖性类别表示的变化将首先出现并最强 在前额叶皮层中。这将支持我们的假设，即前额叶皮层位于顶端皮层上方 在分布式皮质系统中介导执行对认知处理的领域的层次结构，以及 提供有关在细胞处实现此控制的神经机制的一些第一个细节 等级。