Visually Modulated Endogenous Activity

视觉调节内源性活动

• 批准号: 6879493
• 负责人: ERICH E SUTTER
• 金额: $ 17.47万
• 依托单位: SMITH-KETTLEWELL EYE RESEARCH INSTITUTE
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-04-01 至 2006-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6879493
• 关键词: attention; behavioral /social science research tag; brightness discrimination; color visions; electroencephalography; electrophysiology; evoked potentials; form /pattern perception; human subject; neural information processing; vision; visual perception; visual stimulus

DESCRIPTION (provided by applicant): The goal of this project is to test a model of top-down visual processing by noninvasive means in alert human observers. According to this model, the CNS actively explores the visual input, interacting with it through its endogenous activity. The interactions result in a temporal encoding of visual information that will be called visually modulated endogenous activity (VMEA). This response component does not need to correlate directly with abrupt changes in stimulus features and therefore eludes the commonly used techniques of stimulus-locked averaging. The existence of this component can be predicted in any system where the input interacts nonlinearly with fast endogenous processes and has been demonstrated in our pilot study using unconventional analysis tools. It shares many properties with the stimulus dependent synchronized high frequency oscillations found in animal studies. The method used in this study demodulates the endogenous carrier by means of nonlinear operations to retrieve its visual content. One of our aims is to optimize the stimulation and demodulation technique for the problem at hand. Other aims are to investigate the characteristics of the VMEA component and the role it may play in human visual perception. Specifically, we will study its dependence on the attentional state of the subject. We will investigate its dependence on stimulus geometry and color and we will compare the VMEA responses to random patterns with those to meaningful images with similar brightness contrast distributions.

描述（由申请人提供）：该项目的目标是通过非侵入性手段在警觉的人类观察者中测试自上而下的视觉处理模型。根据这个模型，中枢神经系统积极探索视觉输入，通过其内源性活动与之相互作用。这些相互作用导致视觉信息的时间编码，这将被称为视觉调制内源性活动（VMEA）。该响应分量不需要与刺激特征的突然变化直接相关，因此避开了常用的刺激锁定平均技术。这个组件的存在可以预测在任何系统中的输入与快速的内源性过程的非线性相互作用，并已在我们的试点研究中使用非常规的分析工具证明。它与在动物研究中发现的刺激依赖性同步高频振荡有许多相同的性质。本研究所采用的方法是通过非线性运算对内源性载体进行去噪，提取其视觉内容。我们的目标之一是优化的刺激和解调技术的问题。其他目的是调查 VMEA组件的特性及其在人类视觉感知中可能发挥的作用。 具体来说，我们将研究它对受试者注意力状态的依赖性。我们将调查其依赖于刺激的几何形状和颜色，我们将比较VMEA响应随机图案与那些有意义的图像具有相似的亮度对比度分布。