Dynamic mechanisms of active vision in prefrontal cortex

前额皮质主动视觉的动态机制

• 批准号: 9211352
• 负责人: MATTHEW A SMITH
• 金额: $ 37.8万
• 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/9211352
• 关键词: Address; Affect; Amblyopia; Area; Attention; Behavior; Behavioral; 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; Outcome; Perception; Performance; Play; Population; Positioning Attribute; Prefrontal Cortex; Primates; Property; Prosthesis; 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; active vision; attentional control; base; brain repair; cognitive function; cognitive process; experience; experimental study; 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; response; spatial neglect; success; vision rehabilitation; visual information; visual motor; visual processing; visual stimulus

DESCRIPTION (provided by applicant): 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.

描述（由申请人提供）：在自然条件下，当我们扫描丰富的视觉环境时，我们的视觉体验以频繁的眼动为特征。然而，大多数实验都集中在视觉和行为贫困条件下的神经反应上，牺牲了现实的拖延条件。人们越来越认识到，在这些条件下，大脑的活动并不总是概括为更自然的环境，并且需要在更复杂的情况下探测神经元动力学的实验。该应用的长期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感知，尽管眼睛频繁地运动和内部认知状态变化。额眼磁场（FEF）是控制囊眼运动至关重要的前额叶皮层的一部分，它通过其在皮质层次结构中的独特位置在此功能中起关键作用。 FEF神经元既可以使用视觉和运动功能，又可以与控制眼睛和视觉皮质区域的皮层结构连接。 FEF神经元如何在此网关中起作用，服务于集成视觉信息以引导眼动并告知视觉系统有关计划的电机命令的双重功能？一个线索来自对预测重映射现象的研究，在该现象中，神经元在即将发生的扫视之前转移其空间偏好。这发生在FEF神经元以及其他皮质区域，并暗示其响应特性的频繁而动态变化。运动计划带来了哪些动态变化？产生这些动力学所需的信息如何通过神经元电路传播？我们将以三个特定的目的解决这些问题，其中第一个使用迅速提出的稀疏噪声刺激，这是一种在早期视觉区域开发的方法，以探测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，可以对快速闪烁的刺激和非线性空间求和产生反应，从而导致对小刺激的强烈反应，这些刺激被视为潜在的扫视靶标。第二个具体目的是使用相同的噪声刺激测量具有高空间和时间精度的预测重新映射响应。我们假设重新映射表现为在围场时期的接收场逐渐变化，这对于引导的扫视和更自然主义的自发扫视都会发生这种情况。在第三个特定目的中，我们试图通过同时记录FEF神经元的人群来隔离负责这些动态变化的神经元电路。我们假设FEF内的局部电路被调用以在眼睛运动之前传递神经元之间的信息。这项研究的总体结果是确定FEF在主动视觉过程中整合视觉感知和运动控制的作用，并构建一个框架，用于使用接受性场所映射和种群记录来衡量视觉和运动系统跨视觉和运动的动态变化。这将有助于发展创伤后视力和康复神经系统疾病的治疗方法 受伤或疾病。