Tuning for Complex Visual Stimuli in V1

V1 中复杂视觉刺激的调整

• 批准号: 6684769
• 负责人: ANIRUDDHA DAS
• 金额: $ 40.88万
• 依托单位: COLUMBIA UNIVERSITY HEALTH SCIENCES
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-07-07 至 2007-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6684769
• 关键词: Macaca; brain mapping; cell cell interaction; electrical measurement; electrodes; imaging /visualization /scanning; neural information processing; neurons; optics; retina; sensory receptors; single cell analysis; visual cortex; visual perception; visual stimulus

DESCRIPTION (provided by applicant): The long-term goal of this work is to understand the neural mechanisms of visual form perception. The current project aims to study the processing of modestly complex visual stimuli such as smooth contours, junctions and texture boundaries in primary visual cortex (V1). Recent evidence suggests that V1 is much more than just a bank of filters that passively extracts the simplest elements (e.g. short oriented line segments) from all visual input, as was earlier believed. Rather, the elemental components of complex stimuli interact strongly with each other to give V1 responses that could differ dramatically from the responses to the individual components. The current project is intended to test the hypothesis that such complex visual processing can be predicted from the columnar architecture and intrinsic circuitry of VI. In particular, it is proposed that cortical columns tuned to elemental components of a complex stimulus (e.g. line segments at particular retinotopic positions, orientations, color contrast etc.) facilitate and inhibit each other in predictable ways through intrinsic V1 circuitry to generate tuning for the composite whole. Further, that the complex tuning of any given V1 neuron can be predicted from its geographical position on cortex relative to columns activated by the complex stimulus in question. This hypothesis will be tested by studying the V1 processing for different families of complex stimuli including smooth contours, junctions and texture boundaries that are perceptually important for scene segmentation. A combination of optical imaging and electrode recordings in alert monkey V1 will be used for this study. Optical imaging will allow for mapping the cortical positions of neurons responding to each complex stimulus and its individual components. Electrode recordings and cross correlations, guided by optical images, will be used to measure the intracortical interactions between the same groups of neurons. The complex tuning computed on the basis of these interactions can then be compared with the measured values and thus test our hypothesis. The proposed combination of optical imaging and electrode recording will make it possible to elucidate the geometry of cortical mechanisms underlying V1 tuning, a goal that is not reachable through electrode recordings alone. The results of this study will provide a broad framework for understanding the cortical processing of complex visual stimuli, an essential step for clinical applications including the design of visual prostheses for the blind.

描述（由申请人提供）：这项工作的长期目标是了解视觉形式感知的神经机制。当前的项目旨在研究原代视觉皮层（V1）中平滑轮廓，连接和纹理边界等适度复杂的视觉刺激的处理。最近的证据表明，V1不仅仅是一堆过滤器，这些过滤器被动地从所有视觉输入中被动提取最简单的元素（例如，短方向线段）。相反，复杂刺激的元素成分相互相互作用，从而给出V1响应，这些响应可能与对单个组件的响应有很大差异。当前的项目旨在检验以下假设：可以从VI的柱状架构和内在电路中预测这种复杂的视觉处理。特别是，有人提出，调谐到复杂刺激的元素成分的皮质柱（例如，特定视网膜位置的线段，方向，颜色对比等）促进并通过固有的V1电路以可预测的方式互相抑制，以使整个复合材料整体发电。此外，可以从相对于所讨论的复合刺激激活的柱上的柱子上的地理位置来预测任何给定V1神经元的复杂调整。该假设将通过研究不同复杂刺激族的V1处理，包括平滑的轮廓，连接和纹理边界，这对场景细分至关重要。这项研究将使用光学成像和电极记录的组合。光学成像将允许映射响应于每个复杂刺激及其单个成分的神经元的皮质位置。电极记录和以光学图像为指导的电极记录和跨相关性将用于测量同一神经元组之间的皮质内相互作用。然后，根据这些相互作用计算的复杂调整可以与测量值进行比较，从而检验我们的假设。所提出的光学成像和电极记录的组合将使阐明V1调谐基础的皮质机制的几何形状成为可能，这一目标无法通过单独的电极记录实现。这项研究的结果将为理解复杂的视觉刺激的皮质处理提供一个广泛的框架，这是临床应用的重要步骤，包括设计视觉假体的盲人。