Dynamic mechanisms of active vision in prefrontal cortex

前额皮质主动视觉的动态机制

• 批准号: 8628457
• 负责人: MATTHEW A SMITH
• 金额: $ 37.65万
• 依托单位: UNIVERSITY OF PITTSBURGH AT PITTSBURGH
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-02-01 至 2019-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8628457
• 关键词: Address; Affect; Amblyopia; Area; Attention; Behavior; Brain; Brain Diseases; Code; Cognitive; Communication; Decision Making; Diagnosis; Disease; Environment; Eye; Eye Movements; Fire - disasters; Goals; Individual; Investigation; Lead; Linear Models; Link; Macaca; Macular degeneration; Maps; Measurement; Measures; Memory; Methods; Motor; Nervous system structure; Neurons; Noise; Nonlinear Dynamics; Outcome; Perception; Performance; Play; Population; Positioning Attribute; Prefrontal Cortex; Primates; Process; Property; Prosthesis; Rehabilitation therapy; Reporting; Research; Role; Saccades; Scanning; Sensory; Shapes; Signal Transduction; Source; Stimulus; Structure; System; Testing; Time; Traumatic Brain Injury; Vision; Visual; Visual Agnosias; Visual Cortex; Visual Perception; Visual attention; Visual system structure; Work; active vision; base; brain repair; cognitive function; experience; extrastriate visual cortex; flexibility; frontal eye fields; frontal lobe; improved; meetings; motor control; nervous system disorder; neural circuit; neuronal circuitry; oculomotor; preference; public health relevance; receptive field; relating to nervous system; research study; response; spatial neglect; success; visual information; visual motor; visual process; visual processing; visual stimulus

Dynamic mechanisms of active vision in prefrontal cortex PROJECT SUMMARY Under natural conditions, our visual experience is characterized by frequent eye movements as we scan a rich visual environment. Most experiments, however, have focused on neural responses under visually and behaviorally impoverished conditions, sacrificing realistic conditions for tractability. There is a growing realization that the brain's activity under these conditions does not always generalize to more natural settings, and experiments that probe neuronal dynamics under more complicated situations are needed. The long-term goal of this application is to determine how neural circuits in the primate brain act to generate coherent visual perception despite frequent eye movements and changes in internal cognitive state. The frontal eye field (FEF), a part of prefrontal cortex critical for controlling saccadic eye movements, plays a key role in this function through its unique position in the cortical hierarchy. FEF neurons serve both visual and motor functions, with connections to subcortical structures that control the eyes and to visual cortical areas. How do FEF neurons act in this gateway, serving the dual functions of integrating visual information to guide eye movements and informing the visual system about planned motor commands? One clue comes from studies of the phenomenon of predictive remapping, in which neurons shift their spatial preferences prior to an impending saccade. This occurs in FEF neurons as well as other cortical areas, and hints at the frequent and dynamic changes in their response properties. What kinds of dynamic changes are brought on by motor planning? How does the information necessary to generate these dynamics propagate through neuronal circuits? We will address these questions in three specific aims, the first of which uses rapidly presented sparse noise stimuli, an approach developed in early visual areas, to probe the dynamics of FEF neuronal responses. We hypothesize that FEF neurons have precise temporal dynamics, enabling responses to rapidly flashed stimuli, and nonlinear spatial summation, leading to strong responses to small stimuli that are perceived as potential saccade targets. The second specific aim is to measure the predictively remapped response with high spatial and temporal precision using the same noise stimulus. We hypothesize that remapping manifests as a gradual shift in the receptive field in the peri-saccadic time period, and this occurs for both guided saccades and more naturalistic spontaneous saccades. In the third specific aim, we attempt to isolate the neuronal circuitry responsible for these dynamic changes by recording simultaneously from a population of FEF neurons. We hypothesize that local circuitry within FEF is invoked to transfer information between neurons prior to an eye movement. The overall result of this study will be to establish the role of FEF in integrating visual perception and motor control during active vision, and to construct a framework for using receptive field mapping and population recordings to measure dynamic changes in neural circuits across visual and motor systems. This will aid in developing treatments for neurological disorders of vision and rehabilitation after traumatic brain injury or disease.

主动视觉的前额叶皮层动力学机制 项目摘要 在自然条件下，我们的视觉体验的特点是频繁的眼球运动，因为我们扫描丰富的 视觉环境然而，大多数实验都集中在视觉和视觉刺激下的神经反应上。 行为贫困的条件，牺牲现实条件的顺从性。人们越来越 意识到大脑在这些条件下的活动并不总是适用于更自然的环境， 并且需要在更复杂的情况下探测神经元动力学的实验。长期 这个应用的目标是确定灵长类动物大脑中的神经回路如何产生连贯的视觉 尽管频繁的眼球运动和内部认知状态的变化，前视野（FEF）， 前额叶皮层的一部分对控制扫视眼球运动至关重要，在这一功能中起着关键作用 通过它在大脑皮层的独特位置FEF神经元具有视觉和运动功能， 连接到控制眼睛的皮层下结构和视觉皮层区域。FEF神经元如何作用 在这个网关中，具有整合视觉信息以引导眼球运动和 告知视觉系统计划好的运动指令一条线索来自于对 预测性重新映射现象，其中神经元在即将发生的事件之前改变其空间偏好。 扫视这发生在FEF神经元以及其他皮层区域，并暗示了频繁和动态的 它们的响应特性的变化。运动规划带来了什么样的动态变化？如何 产生这些动力学所必需的信息是否通过神经元回路传播？我们将 解决这些问题在三个具体的目标，其中第一个使用快速提出稀疏噪声刺激， 方法开发的早期视觉领域，探测FEF神经元反应的动力学。我们假设 FEF神经元具有精确的时间动力学，能够对快速闪光的刺激做出反应，并且是非线性的。 空间总和，导致对被感知为潜在扫视目标的小刺激的强烈反应。 第二个具体目标是测量具有高空间和时间的预测性重新映射响应。 使用相同的噪声激励。我们假设，重新映射表现为一个渐进的转变， 感受野在周围扫视时间段，这发生在引导扫视和更自然的 自发性扫视在第三个具体目标中，我们试图分离出负责 这些动态变化通过同时记录FEF神经元的群体。我们假设 FEF内的局部电路被调用以在眼睛运动之前在神经元之间传递信息。的 本研究的总体结果将是确定FEF在整合视觉感知和运动控制中的作用 在主动视觉，并建立一个框架，使用感受野映射和人口记录 来测量视觉和运动系统中神经回路的动态变化。这将有助于发展 治疗视觉神经障碍和创伤性脑损伤或疾病后的康复。