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: 8577420
• 负责人: MICHELE RUCCI
• 金额: $ 38.54万
• 依托单位: BOSTON UNIVERSITY (CHARLES RIVER CAMPUS)
• 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 2016-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8577420
• 关键词: Address; Advocate; Behavior; Characteristics; Code; Computer Analysis; Computer Simulation; Contrast Sensitivity; Data; Disputes; Dyskinetic syndrome; Elements; Eye; Eye Movements; Frequencies; Funding; Goals; Human; Image; Individual; Joints; Knowledge; Lateral Geniculate Body; Lead; Link; Location; Maps; Microscopic; Modeling; Motion; Neurons; Outcome; Phase; Play; Process; Property; Research; Rest; Retina; Retinal; Role; Saccades; Signal Transduction; Simulate; Source; Spatial Distribution; Staging; Stimulus; Structure; System; Testing; Theoretical Studies; Time; United States National Institutes of Health; Vision; Visual; Visual Perception; Visual Psychophysics; Visual impairment; Visual system structure; attenuation; design; experience; flexibility; gaze; luminance; neural model; neuromechanism; oculomotor; public health relevance; receptor; relating to nervous system; research study; response; retinal stimulation; sample fixation; spatial vision; spatiotemporal; transmission process; visual information; visual process; visual processing

PROJECT SUMMARY Our eyes are never at rest, even when attending to a single point. We are normally not aware that, in the peri- ods of fixation, microscopic eye movements continually shift the stimulus on the retina. Visual percepts tend to fade when the stimulus is artificially immobilized on the retina, and it has long been hypothesized that the inces- sant fixational motion of the eye plays a fundamental role in visual perception. Several findings from our recent NIH-funded research suggest that this motion is, in fact, a critical computational element of an active sensori- motor strategy by which the visual system processes spatial information in the temporal domain. Building upon our recent results, this project examines the perceptual, computational, and neural consequences of using eye movements to represent space through time. It addresses three fundamental questions: (Aim 1) How is spatial information encoded in the modulations of luminance resulting from fixational eye movements? (Aim 2) How is this information extracted and interpreted? (Aim 3) Can the spatiotemporal redistribution of input energy be adjusted according to task by controlling fixational eye movements? To link the perceptual influences of fixational eye movements to their effect on the neural coding of visual information and elucidate encoding/decoding mech- anisms, this project integrates visual psychophysics in humans, statistical and computational analysis of retinal input, and neural modeling. Experiments will make critical use of a sophisticated system for gaze-contingent display (already developed and extensively tested), which allows precise, yet highly flexible control of retinal stim- ulation. Statistical, computational, and modeling studies will reconstruct and examine the visual input signals experienced by retinal receptors and simulate neuronal responses in the retina and lateral geniculate nucleus. The proposal that the visual system uses behavior to represent space through time challenges current views on the mechanisms of early visual processing at the most fundamental level: it replaces the traditional notion of the retina as a passive encoding stage that optimizes overall information transmission with that of an active, tunable system for feature extraction, whose function can only be understood in conjunction with eye movements. This shift of view implies that eye movements are in part responsible for fundamental properties of spatial vision (e.g., contrast sensitivity and its dynamics) that, at present, are solely attributed to neural mechanisms. Under- standing the functional implications of fixational instability may also lead to new treatment approaches for visual impairments in the many disorders whose manifestations include abnormal fixational eye movements.

项目摘要 即使在一个点上，我们的眼睛也永远不会静止。我们通常不知道，在周期中 固定的OD，微观眼动动作不断移动视网膜上的刺激。视觉感知往往 当刺激被人为地固定在视网膜上时，逐渐消失，并且长期以来一直假设这些刺激刺激了 - 眼睛的固定运动在视觉感知中起着基本作用。我们最近的一些发现 NIH资助的研究表明，这种运动实际上是主动传感器的关键计算元素 视觉系统在时间域中处理空间信息的电机策略。建立 我们最近的结果，该项目研究了使用眼的感知，计算和神经后果 动作以表示空间。它解决了三个基本问题：（目标1）如何空间 在固定眼动作引起的亮度调制中编码的信息？ （目标2）如何 这些信息是否提取和解释？ （目标3）输入能量的时空重新分布可以 通过控制固定眼动作根据任务进行调整？链接固定的感知影响 眼动作对视觉信息的神经编码的影响，并阐明编码/解码机甲 - anisms，该项目整合了人类中的视觉心理物理学，视网膜的统计和计算分析 输入和神经建模。实验将对凝视诱导的复杂系统进行批判性使用 显示（已经开发和经过广泛测试），可以精确但高度灵活地控制视网膜刺激 Ulation。统计，计算和建模研究将重建和检查视觉输入信号 通过视网膜受体体验并模拟视网膜和侧向核核中的神经元反应。 视觉系统使用行为来表示空间的提议，挑战当前视图 关于最基本的早期视觉处理的机制：它取代了传统概念 视网膜作为一个被动编码阶段，可通过主动信息优化总体信息传输 可调系统用于特征提取的系统，其功能只能与眼动。 这种观点的转变意味着眼睛运动部分负责空间视觉的基本属性 （例如，对比灵敏度及其动力学）目前仅归因于神经机制。在下面- 站立固定不稳定性的功能含义也可能导致视觉的新治疗方法 许多疾病的障碍都包括异常的固定眼运动。