Updating location information across object and eye movements

更新物体和眼球运动的位置信息

基本信息

批准号：
8009777
负责人：
Julie D Golomb
金额：
$ 4.84万
依托单位：
MASSACHUSETTS INSTITUTE OF TECHNOLOGY
依托单位国家：
美国
项目类别：
财政年份：
2009
资助国家：
美国
起止时间：
2009-12-01 至 2012-11-30
项目状态：
已结题

项目摘要

DESCRIPTION (provided by applicant): Effective interaction with our visual world requires us to represent both the identities and locations of objects, and to maintain this information as the objects themselves move, and as our eyes move over the objects. Directing attention toward a behaviorally relevant location facilitates the processing of objects in that location. But what happens if the eyes move while a location is facilitated? With each eye movement, the retinotopic (eye-centered) coordinates of the attended location change while the spatiotopic (world-centered) coordinates remain stable. A set of preliminary experiments revealed that facilitation temporarily remains at the previously relevant retinotopic location, even when the task requires updating to spatiotopic coordinates and the retinotopic location should have been invalidated by the intervening saccade (Golomb et al, 2008). This "retinotopic attentional trace" has been demonstrated for low-level spatial attention and discrimination of simple stimuli across saccades, but does it generalize to sustained representations of complex objects and actions? Aim 1 explores the generality of retinotopic attentional traces in a series of psychophysical experiments that manipulate the type of attention, nature of the coordinate frame shift, and mode of interaction with the stimuli. Aim 2 explores the neural basis of these effects with fMRI using (1) multivariate pattern analysis to determine how different visual areas express basic location information, (2) an ROI- based analysis to explore how representations of attended locations are updated following a saccade, and (3) repetition attenuation to ask how these representations are influenced by top-down demands when object location and/or identity is emphasized. These explorations of the scope, effects, and neural basis of the retinotopic attentional trace should help illuminate the nature of location coding in the visual system and the mechanisms by which the visual system updates location information as eyes and objects move. PUBLIC HEALTH RELEVANCE: Consistent with the NEI mission, this proposal aims to advance basic research in understanding the mechanisms of normal visual function. This research has implications for how the visual system functions in disease in addition to health: a variety of clinical conditions result in deficits at all stages of visual processing addressed by this research, affecting an individual's ability to locate important information in a cluttered scene, to perceive and recognize objects, and to integrate information across eye movements. To apply these findings to clinical populations, however, the basic research outlined in the proposal is necessary to more fully understand how visual locations are updated across object and eye movements in normally functioning adults

描述（由申请人提供）：与我们的视觉世界的有效交互需要我们表示对象的身份和位置，并在对象本身移动以及我们的眼睛在对象上移动时维护这些信息。将注意力引向行为相关的位置有助于处理该位置的物体。但是，如果在确定位置时眼睛移动，会发生什么情况呢？随着每次眼球运动，所关注位置的视网膜主题（以眼睛为中心）坐标会发生变化，而空间主题（以世界为中心）坐标保持稳定。一组初步实验表明，即使任务需要更新空间坐标，并且视网膜主题位置应该因介入扫视而失效，促进仍暂时保留在先前相关的视网膜主题位置（Golomb 等人，2008）。这种“视网膜专题注意力轨迹”已被证明可用于低水平的空间注意力和跨眼跳的简单刺激的辨别，但它是否可以推广到复杂物体和动作的持续表征？目标 1 探讨了一系列心理物理学实验中视网膜专题注意力痕迹的普遍性，这些实验操纵注意力类型、坐标系移动的性质以及与刺激的相互作用模式。目标 2 通过 fMRI 探索这些效应的神经基础，使用 (1) 多变量模式分析来确定不同视觉区域如何表达基本位置信息，(2) 基于 ROI 的分析来探索扫视后如何更新关注位置的表示， (3) 重复衰减，以询问当强调对象位置和/或身份时，自上而下的要求如何影响这些表示。这些对视网膜专题注意轨迹的范围、效应和神经基础的探索应该有助于阐明视觉系统中位置编码的本质以及视觉系统在眼睛和物体移动时更新位置信息的机制。公共卫生相关性：与 NEI 的使命一致，该提案旨在推进了解正常视觉功能机制的基础研究。除了健康之外，这项研究还对视觉系统在疾病中的功能产生影响：各种临床状况会导致本研究解决的视觉处理各个阶段的缺陷，影响个体在杂乱场景中定位重要信息的能力，感知和识别物体，并整合眼球运动的信息。然而，为了将这些发现应用于临床人群，提案中概述的基础研究对于更全面地了解功能正常的成年人的视觉位置如何在物体和眼球运动中更新是必要的