Dynamic mechanisms of active vision in prefrontal cortex

前额皮质主动视觉的动态机制

• 批准号: 8791694
• 负责人: MATTHEW A SMITH
• 金额: $ 37.04万
• 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/8791694
• 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; Health; 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; 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; attentional control; base; brain repair; cognitive function; cognitive process; experience; extrastriate visual cortex; flexibility; frontal eye fields; frontal lobe; improved; meetings; motor control; nervous system disorder; neural circuit; neuronal circuitry; oculomotor; preference; receptive field; relating to nervous system; research study; response; spatial neglect; success; visual information; visual motor; visual process; 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，我们的视觉体验的特点是当我们扫描丰富的视觉环境时频繁的眼球运动。然而，大多数实验都集中在视觉和行为匮乏条件下的神经反应，牺牲了现实条件以实现易处理。人们越来越认识到，这些条件下的大脑活动并不总是能推广到更自然的环境，因此需要进行实验来探索更复杂情况下的神经元动力学。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在频繁的眼球运动和内部认知状态变化的情况下产生连贯的视觉感知。额叶眼区 (FEF) 是前额皮质的一部分，对于控制眼跳运动至关重要，通过其在皮质层次结构中的独特位置，在这一功能中发挥着关键作用。 FEF 神经元具有视觉和运动功能，与控制眼睛的皮层下结构和视觉皮层区域有联系。 FEF 神经元如何在这个网关中发挥作用，发挥整合视觉信息以引导眼球运动和向视觉系统通报计划的运动命令的双重功能？一条线索来自对预测重映射现象的研究，即神经元在即将发生的眼跳之前改变其空间偏好。这种情况发生在 FEF 神经元以及其他皮质区域，暗示其反应特性频繁且动态地变化。运动规划会带来哪些动态变化？产生这些动态所需的信息如何通过神经元回路传播？我们将通过三个具体目标来解决这些问题，第一个目标是使用快速呈现的稀疏噪声刺激（一种在早期视觉区域开发的方法）来探测 FEF 神经元反应的动态。我们假设 FEF 神经元具有精确的时间动态，能够对快速闪烁的刺激做出反应，并且具有非线性空间求和，从而导致对被视为潜在扫视目标的小刺激产生强烈反应。第二个具体目标是使用相同的噪声刺激以高空间和时间精度测量预测性重映射响应。我们假设重新映射表现为眼跳周围时间段内感受野的逐渐变化，这种情况在引导眼跳和更自然的自发眼跳中都会发生。在第三个具体目标中，我们尝试通过同时记录 FEF 神经元群体来分离负责这些动态变化的神经元回路。我们假设在眼球运动之前，FEF 内的局部电路被调用以在神经元之间传输信息。这项研究的总体结果将是确立 FEF 在主动视觉过程中整合视觉感知和运动控制中的作用，并构建一个使用感受野映射和群体记录来测量视觉和运动系统神经回路动态变化的框架。这将有助于开发治疗视觉神经系统疾病和脑外伤后康复的方法 受伤或疾病。