Synaptic basis for visual cortical receptive field properties

视觉皮层感受野特性的突触基础

• 批准号: 8298180
• 负责人: Yang DAN
• 金额: $ 34.83万
• 依托单位: UNIVERSITY OF CALIFORNIA BERKELEY
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-07-01 至 2014-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8298180
• 关键词: Accounting; Address; Brain; Cells; Code; Complex; Computational Technique; Dimensions; Epilepsy; Equilibrium; Evolution; Felis catus; Future; Goals; Health; Individual; Knowledge; Light; Maps; Measures; Mediating; Mental disorders; Modeling; Modification; Motion; Neocortex; Neurons; Neurosciences; Phase; Play; Positioning Attribute; Process; Property; Rattus; Research; Role; Shapes; Signal Transduction; Spatial Distribution; Stimulus; Structure; Sum; Synapses; Techniques; Testing; V1 neuron; Vision; Visual; Visual Cortex; Visual Illusions; area striata; base; cognitive function; extracellular; nervous system disorder; neural circuit; neuronal circuitry; novel; patch clamp; receptive field; response; spatiotemporal; therapy development; visual information; visual stimulus

DESCRIPTION (provided by applicant): The mammalian neocortex mediates a variety of cognitive functions, and understanding the circuit basis for cortical processing is a central goal in neuroscience. In the primary visual cortex (V1), the receptive field properties of individual neurons have been characterized extensively, but the underlying neuronal circuitry remains unclear. The goal of the proposed research is to dissect the excitatory and inhibitory synaptic inputs underlying the spatiotemporal receptive fields of V1 neurons. Experimentally, we will make intracellular (patch clamp) recordings in anesthetized rats and cats to measure the synaptic inputs to cortical neurons. Computationally, we will apply both linear and nonlinear analyses to determine the receptive field properties of each input. There are four specific aims. Aim 1 is to characterize the synaptic mechanisms underlying the basic receptive field and direction selectivity of simple cells. To test the anti-phase inhibition model, we will determine the extent to which the excitatory and inhibitory receptive fields are matched to each other with opposite ON/OFF polarities. The contributions of several proposed mechanisms to simple cell direction selectivity will be assessed. Aim 2 is to characterize the synaptic circuitry underlying the receptive field subunits of complex cells. The predictions of different circuit models for complex cell RFs will be tested. We will also determine the contributions of several proposed mechanisms to complex cell direction selectivity. In Aims 3 and 4 we will address two of the more advanced receptive field properties involved in processing motion stimuli. Our recent study using extracellular recordings indicated a spatial asymmetry in direction-selective inputs to V1 neurons, which gives rise to two novel RF properties that could account for two visual illusions. In Aim 3, we will examine the spatial distributions of direction-selective excitatory and inhibitory inputs in order to test and constrain the asymmetric circuit model. In Aim 4, we will measure the effects of motion adaptation on the strength and direction selectivity of excitatory and inhibitory synaptic input to determine how these inputs contribute to adaptation-induced change in V1 direction selectivity. To further test the asymmetric circuit model, we will also measure the effect of motion adaptation on the spatial distributions of the excitatory and inhibitory inputs. Such comprehensive characterization of the synaptic mechanisms underlying cortical receptive field properties is not only crucial for understanding V1 functions, but also likely to shed light on the general principles of cortical computation. PUBLIC HEALTH RELEVANCE Balance between excitation and inhibition in the cortex is critical for normal brain functions, and disruption of the balance causes a variety of mental disorders. The proposed research aims to understand the relationship between excitatory and inhibitory inputs, and how they shape the functional properties of visual cortical neurons. Such knowledge will be crucial for the development of treatment for not only deficiencies in visual functions, but also other neurological disorders such as epilepsy.

描述（由申请人提供）：哺乳动物的新皮层介导了多种认知功能，了解皮质加工的电路基础是神经科学的核心目标。在一级视觉皮层（V1）中，已经对单个神经元的接受场特性进行了广泛的表征，但是基本的神经元回路尚不清楚。拟议的研究的目的是剖析V1神经元时空接受场的兴奋性和抑制性突触输入。在实验上，我们将在麻醉大鼠和猫中进行细胞内（贴片夹）记录，以测量皮质神经元的突触输入。在计算上，我们将同时应用线性和非线性分析来确定每个输入的接受场特性。有四个具体目标。目的1是表征基本接受场和简单细胞的方向选择性的突触机制。为了测试抗相期抑制模型，我们将确定兴奋性和抑制性接收场相互匹配的程度与相反的极性相反。将评估几种提出机制对简单细胞方向选择性的贡献。目的2是表征复杂细胞的接收场亚基的基础突触电路。将测试不同电路模型的不同电路模型的预测。我们还将确定几种提出的机制对复杂细胞方向选择性的贡献。在目标3和4中，我们将解决与加工运动刺激有关的两个更先进的接收场特性。我们最近使用细胞外记录的研究表明，对V1神经元的方向选择性输入的空间不对称性，这引起了两种新型的RF特性，可以说明两个视觉幻觉。在AIM 3中，我们将检查方向选择性兴奋性和抑制性输入的空间分布，以测试和限制不对称电路模型。在AIM 4中，我们将测量运动适应对兴奋性和抑制性突触输入的强度和方向选择性的影响，以确定这些输入如何有助于自适应诱导的V1方向选择性变化。为了进一步测试不对称电路模型，我们还将测量运动适应对兴奋性和抑制性输入空间分布的影响。对皮质接受场特性的突触机制的这种全面表征不仅对于理解V1功能至关重要，而且很可能阐明皮质计算的一般原理。公共卫生相关性平衡与皮质中的抑制作用对于正常的大脑功能至关重要，平衡的破坏会导致各种精神障碍。拟议的研究旨在了解兴奋性和抑制性输入之间的关系，以及它们如何塑造视觉皮质神经元的功能特性。这种知识对于不仅为视觉功能缺陷的缺乏，而且还有其他神经系统疾病（例如癫痫）的治疗至关重要。