Neural processing in the ventral visual pathway during object search

物体搜索过程中腹侧视觉通路的神经处理

• 批准号: 7945872
• 负责人: NICOLE C RUST
• 金额: $ 39.02万
• 依托单位: UNIVERSITY OF PENNSYLVANIA
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-08-01 至 2015-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7945872
• 关键词: Accounting; Area; Brain; Code; Cues; Data; Dependency; Face; Goals; Human; Image; Individual; Length; Measures; Memory; Modeling; Neurons; Outcome; Phase; Play; Population; Positioning Attribute; Process; Prosthesis; Role; Sampling; Sensory; Signal Transduction; Stimulus; Testing; Visual; Visual Cortex; Visual Pathways; Visual Perception; Visual system structure; area V4; detector; extrastriate visual cortex; population based; public health relevance; relating to nervous system; repaired; response; visual information; visual process; visual processing; visual stimulus

DESCRIPTION (provided by applicant): The goal of this proposal is to arrive at an accurate description of the multiple roles that visual areas in the brain play when we are looking for a specific visual object. Locating a specific object requires that we 1) activate a remembered, neural representation of our sought target, 2) develop a neural representation of each item we encounter as we search, and 3) compare these two representations to determine whether the object currently in view matches the object that we seek. We know that the process of remembering an object activates neurons in classically defined 'visual' areas of the brain, suggesting that these visual areas may play a role beyond statically processing the visual scene when searching for an object. This notion is supported by other lines of evidence, including our own preliminary data. In Specific Aim 1, we propose to characterize this role by measuring the degree to which the visual representation of a currently viewed stimulus also depends on the identity of a sought target at different levels of visual processing (i.e. areas V4 and IT). Upon finding such dependencies, we will seek to determine what they accomplish. For example, the visual system might adjust its detectors to increase the discriminability of a target. Similarly, the responses of these visual neurons may represent the outcome of a comparison between the target and the scene currently held in view. In Specific Aim 2, we are motivated by the notion that real-world object search involves finding an object across changes in position, size, background and pose, and we propose to characterize the role of the visual system in searching for a target across a subset of these identity- preserving object transformations. Finally, in Specific Aim 3, we propose to characterize the activity of visual neurons when a visual stimulus is held in memory but no visual stimulus is physically present ("persistent activity") to better understand the neural signature of the remembered and sought target in the visual system. PUBLIC HEALTH RELEVANCE: To understand how visual information is processed in the brain, it is fundamental to understand how the external world is represented by neural signals in visual cortex and how memories and goals influence and interact with that representation. This proposal seeks to understand the fundamental principles by which the visual system transforms the neural representation of images when looking for a specific visual object. Understanding the neural coding of objects is critical to a deep understanding of human visual perception and memory, and is needed to meaningfully repair the disruption of these brain processes or to create prosthetics that may stand in for such disruption.

描述（由申请人提供）：该提案的目的是准确描述当我们寻找特定的视觉对象时，大脑中视觉区域扮演的多个角色。找到一个特定的对象要求我们1）激活我们所寻求的目标的记忆，神经表示，2）在搜索时开发一个我们遇到的每个项目的神经表示，以及3）比较这两个表示，以确定当前是否与我们所寻求的对象相匹配。我们知道，记住对象的过程会激活大脑的经典定义“视觉”区域中的神经元，这表明这些视觉区域在搜索对象时可能会在静态处理视觉场景之外发挥作用。该概念得到了其他证据，包括我们自己的初步数据。在特定的目标1中，我们建议通过测量当前观察的刺激的视觉表示的程度来表征这种角色，这也取决于在不同级别的视觉处理（即区域V4和IT）处的寻求靶标的身份。找到这样的依赖性后，我们将寻求确定他们的成就。例如，视觉系统可能会调整其检测器以增加目标的可区分性。同样，这些视觉神经元的响应可能代表目标与目前在观察的场景之间进行比较的结果。在特定的目标2中，我们的动机是，现实世界对象搜索涉及在位置，大小，背景和姿势的变化中找到对象，并且我们建议表征视觉系统在跨这些身份的子集搜索目标 - 保留对象变换的子集中的目标中的作用。最后，在特定的目标3中，我们建议在记忆中保持视觉刺激时表征视觉神经元的活性，但没有物理上存在视觉刺激（“持续活动”），以更好地理解视觉系统中记忆和寻求目标的神经特征。 公共卫生相关性：了解如何在大脑中处理视觉信息，了解外部世界如何由视觉皮层中的神经信号代表，以及记忆和目标如何影响和与该表示形式相互作用。该建议试图了解视觉系统在寻找特定视觉对象时会改变图像的神经表示的基本原理。了解对象的神经编码对于对人类视觉感知和记忆的深刻理解至关重要，并且需要有意义地修复这些大脑过程的破坏或创造可能影响这种破坏的假肢。