Function of Fixational Instability During Natural Viewing

自然观看过程中注视不稳定性的作用

• 批准号: 10442064
• 负责人: MICHELE RUCCI
• 金额: $ 55万
• 依托单位: UNIVERSITY OF ROCHESTER
• 依托单位国家: 美国
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-09-01 至 2026-07-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10442064
• 关键词: 3-Dimensional; Address; Advocate; Affect; Area; Automobile Driving; Behavior; Binocular Vision; Cephalometry; Characteristics; Code; Data; Depth Perception; Development; Disease; Eye; Eye Abnormalities; Eye Movements; Foundations; Frequencies; Funding; Goals; Head; Human; Image; Image Enhancement; Impairment; Intuition; Investigation; Knowledge; Light; Location; Mainstreaming; Maps; Measurement; Modeling; Motion; Motor; Movement; Names; Nature; Neurons; Ocular Fixation; Ophthalmology; Optics; Outcome; Pattern; Perception; Play; Process; Prosthesis; Reporting; Research; Resolution; Retina; Role; Saccades; Shapes; Signal Transduction; Stimulus; Stream; Testing; Time; United States National Institutes of Health; Vision; Vision Disparity; Visual; Visual impairment; Visual system structure; Work; base; experimental study; flexibility; gaze; information processing; instrumentation; luminance; monocular; multimodality; neglect; novel; oculomotor; predictive test; receptor; rehabilitation strategy; relating to nervous system; retinal imaging; retinal stimulation; sample fixation; spatiotemporal; theories; vision science; visual motor

PROJECT SUMMARY Humans are not aware that their eyes are always in motion. Even when attending to a single point, fixational eye movements (FEM) continually shift the stimulus on the retina in ways that would be immediately visible had the motion originated from objects in the scene rather than oculomotor activity. It is now clear that FEM are vital for visual sensitivity, fine pattern vision, and acuity. Furthermore, a considerable body of evidence, in part from our NIH-funded research, indicates that this behavior embodies a sensorimotor strategy by which the visual system processes spatial information in the temporal domain. While much has been learned about the monoc- ular functions of FEM, little is known about their consequences for binocular vision. Ocular drifts—the incessant inter-saccadic movements—differ considerably in the two eyes. How does the visual system combine continually changing inputs from independently jittering eyes? Here we focus on FEM consequences for 3D spatial repre- sentations, specifically their role in stereopsis (Aim 1), their decoding mechanisms (Aim 2), and their binocular control (Aim 3). The research strategy consists of assessing FEM effects on the binocular visual input and ex- amining the resulting implications for neural coding, perception, and control. Our driving hypothesis is that the active space-time encoding strategy that emerged in the monocular processing of luminance also applies to pro- cessing binocularly-derived features at later stages of the visual stream. Since this theory yields counter-intuitive hypotheses, each aim builds on a supporting preparatory study that sets the stage for the proposed experiments. Aim 1 builds on the surprising observation that stereopsis is impaired when fixational disparity modulations are selectively eliminated from the visual flow, even in the presence of otherwise normal luminance modulations on the retina. We will explore the causes for this impairment and elucidate FEM contributions. Aim 2 focuses on the mechanisms by which the fixational visual flow is interpreted. Contrary to traditional assumptions, our prelimi- nary evidence indicates that the visual system has access to extraretinal knowledge of ocular drift and uses it to infer spatial relations at high spatiotemporal resolution. Aim 3 examines these ideas in the context of oculomotor control. We provide the first comprehensive high-resolution measurements of head-free binocular FEM in natural real-world tasks and test the hypothesis that eye drifts are actively controlled to encode task-relevant features (e.g., disparity, spatial contrast, etc.). The experiments rely on the combination of (a) binocular measurements of human eye movements with unprecedented accuracy; and (b) highly flexible, binocularly synchronized, gaze- contingent control of retinal stimulation, an approach made possible by our recent instrumentation developments. All experiments are theoretically grounded and all hypotheses supported by new preliminary data. They are, to our knowledge, entirely novel, and confirmation of any of them will have broad implications for understanding the functional principles of the visual system, the computational mechanisms of perception, possible oculomotor contributions to neuro-ophthalmologic disorders, and the development of rehabilitative strategies and prostheses.

项目摘要 人类不知道自己的眼睛总是在运动。即使注意一个点，固定 眼动（FEM）不断以立即可见的方式转移视网膜上的刺激 该运动起源于场景中的对象，而不是动眼活动。现在很明显，女性 对于视觉敏感性，精细图案视觉和敏锐度至关重要。此外，这是一个考虑的证据体，部分 从我们的NIH资助的研究中，该行为体现了一种感觉运动策略 系统处理临时域中的空间信息。虽然已经了解了有关单元的知识 FEM的ULAR功能，对它们对双眼视力的影响知之甚少。眼训练 - 不断的 帕克斯卡间的运动 - 两只眼睛中的差异考虑。视觉系统如何连续组合 从独立抖动的眼睛中改变输入？在这里，我们关注FEM对3D空间代表的后果 特定的文章，特定的角色在立体原理（AIM 1），解码机制（AIM 2）及其双目 控制（目标3）。研究策略包括评估FEM对双眼视觉输入的影响和Ex- 逐渐阐明对神经编码，感知和控制的含义。我们的驾驶假设是 在亮度的单眼处理中出现的主动时空编码策略也适用于 在视觉流的后期阶段，双眼衍生的特征。由于该理论产生了违反直觉的 假设，每个目标都建立在一项支持准备研究的基础上，该研究为提出的实验奠定了基础。 AIM 1建立在一个惊喜观察的基础上，即当固定差异调制为 有选择地从视觉流中删除，即使在有其他正常的亮度调制的情况下 视网膜。我们将探讨这种损害的原因并阐明FEM的贡献。 AIM 2专注于 解释固定视觉流的机制。与传统假设相反，我们 Nary的证据表明，视觉系统可以访问眼外漂移知识，并将其用于 在高空间时间分辨率下推断空间关系。 AIM 3在动眼中检查这些想法 控制。我们提供了自然中无头部双眼FEM的第一个全面的高分辨率测量 现实世界任务并检验了主钻的积极控制以编码任务与任务功能的假设 （例如，差异，空间对比等）。实验依赖于（a）双眼测量的组合 人类的眼睛运动以前所未有的精度； （b）高度灵活，双眼同步，凝视 - 视网膜刺激的偶然控制，我们最近的仪器发展使这种方法成为可能。 所有实验都是理论上的，所有假设都由新的初步数据支持。他们是 我们的知识，完全新颖，并且确认它们都将对理解具有广泛的影响 视觉系统的功能原理，感知的计算机制，可能的眼球运动 对神经性疾病的贡献，以及康复策略和假体的发展。