Dynamics of Population Activity in Visual Cortex

视觉皮层群体活动的动态

• 批准号: 7275289
• 负责人: MATTEO CARANDINI
• 金额: $ 42.22万
• 依托单位: SMITH-KETTLEWELL EYE RESEARCH INSTITUTE
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-09-01 至 2008-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7275289
• 关键词: Address; Affect; Architecture; Area; Cerebral cortex; Depth; Disease; Dyes; Epilepsy; Exposure to; Feedback; Felis catus; Functional disorder; Goals; Health; Image; Individual; Knowledge; Laboratories; Location; Maps; Measurement; Measures; Methods; Mexican; Migraine; Mission; Modeling; National Eye Institute; Neurons; Noise; Numbers; Pathology; Pattern; Photic Stimulation; Population; Population Dynamics; Positioning Attribute; Prevalence; Principal Investigator; Recording of previous events; Reporting; Research; Resolution; Role; Signal Transduction; Source; Space Perception; Stimulus; Sum; Surface; Testing; Thinking; Time; Travel; Tweens; V1 neuron; Visual Cortex; Visual system structure; Work; area striata; base; improved; orientation selectivity; programs; receptive field; response; statistics; stem; visual adaptation; voltage

DESCRIPTION (provided by applicant): The visual cortex is widely held to represent stimulus attributes through the activity of neuronal populations. Goal of this research is to measure these population responses, and in particular to establish how they develop in time (their dynamics). Population responses will be recorded in primary visual cortex (V1) through imaging of voltage-sensitive dyes (VSD). VSD imaging delivers excellent resolution in space and time. These measurements will test the predictions of three basic architectures that have been hypothesized for the circuitry of V1: feedforward, feedback-sharpening, and feedback-broadening. These architectures could coexist and serve different roles, e.g. one could underlie selectivity for stimulus position and another could underlie selectivity for stimulus position. Aim 1: Dynamics of stimulus selectivity. The three architectures make distinct predictions for how the selectivity of population activity evolves during a response. These predictions will be tested through VSD imaging. Aim 2: Functional connectivity. The three architectures involve different layouts of excitatory and inhibitory connections. These layouts will be probed through cross-correlation of VSD signals, extending to populations a method commonly used with single neurons. Aim 3: Adaptation of stimulus selectivity. The three architectures make distinct predictions regarding the effects of visual adaptation. These predictions will be tested through VSD imaging of population responses. Aim 4: Dynamics of ongoing activity. A feedback architecture with strong intracortical connections creates quasi-stable patterns of activity (attractors). The existence of these attractors will be tested by VSD imaging responses to a variety of stimuli, including stimuli whose orientation is ambiguous. Understanding population responses in visual cortex is a key step to advance our knowledge of how the visual system functions in health and disease, a goal at the core of the mission of the National Eye Institute. Relevance: Understanding the working of primary visual cortex will benefit the understanding of the whole cortex, and therefore help develop treatments for pathologies that stem from cortical dysfunction, including epilepsy and migraine. Indeed, the cerebral cortex is widely held to be organized according to a limited number of functional principles, and these principles are best studied in an area that we understand in depth.

描述（由申请人提供）：视觉皮层被广泛认为通过神经元群的活动来表示刺激属性。这项研究的目标是衡量这些人群的反应，特别是确定它们如何及时发展（它们的动态）。通过电压敏感染料 (VSD) 成像，将在初级视觉皮层 (V1) 中记录群体反应。 VSD 成像在空间和时间上提供出色的分辨率。这些测量将测试对 V1 电路假设的三种基本架构的预测：前馈、反馈锐化和反馈展宽。这些架构可以共存并发挥不同的作用，例如一种可能是刺激位置选择性的基础，另一种可能是刺激位置选择性的基础。目标 1：刺激选择性的动态。这三种架构对响应期间群体活动的选择性如何演变做出了不同的预测。这些预测将通过 VSD 成像进行测试。目标 2：功能连接。这三种架构涉及不同的兴奋性和抑制性连接布局。这些布局将通过 VSD 信号的互相关进行探测，将通常用于单个神经元的方法扩展到群体。目标 3：刺激选择性的适应。这三种架构对视觉适应的效果做出了不同的预测。这些预测将通过人群反应的 VSD 成像进行测试。目标 4：持续活动的动态。具有强大皮质内连接的反馈架构创建了准稳定的活动模式（吸引子）。这些吸引子的存在将通过 VSD 成像对各种刺激的反应进行测试，包括方向不明确的刺激。了解视觉皮层的群体反应是增进我们对视觉系统如何在健康和疾病中发挥作用的了解的关键一步，这也是国家眼科研究所使命的核心目标。相关性：了解初级视觉皮层的工作原理将有助于理解整个皮层，因此有助于开发针对皮层功能障碍（包括癫痫和偏头痛）的疾病的治疗方法。事实上，人们普遍认为大脑皮层是根据有限数量的功能原理进行组织的，而这些原理最好在我们深入理解的领域进行研究。