Updating location information across object and eye movements

描述(申请人提供)：与我们的视觉世界的有效互动要求我们既表示对象的身份和位置，并在对象本身移动时以及当我们的眼睛移动到对象上时保持这一信息。将注意力引导到行为相关的位置有助于处理该位置上的物体。但是，如果在方便定位的同时眼睛移动，会发生什么？随着眼睛的每次移动，所关注位置的视网膜坐标(以眼睛为中心)改变，而空间坐标(以世界为中心)保持稳定。一组初步实验显示，即使任务需要更新到空间坐标，并且视网膜位置应该已经被介入的扫视无效，促进作用也暂时保持在以前相关的视网膜位置(Golomb等人，2008年)。这种“视网膜视觉注意轨迹”已经被证明用于低水平的空间注意和对简单刺激的眼跳辨别，但它是否可以概括为对复杂物体和动作的持续表征？目的1在一系列心理物理实验中探索视网膜视觉注意轨迹的共性，这些实验操纵注意的类型、坐标框架移动的性质以及与刺激相互作用的方式。目的2用fMRI探讨这些效应的神经基础：(1)多变量模式分析以确定不同视觉区域如何表达基本位置信息；(2)基于ROI的分析以探索注视位置的表征在扫视后如何更新；以及(3)重复衰减以询问当强调物体位置和/或身份时这些表征如何受自上而下的需求的影响。这些对视网膜视觉注意轨迹的范围、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，这项建议旨在推进了解正常视觉功能机制的基础研究。这项研究对除了健康外，视觉系统在疾病中的功能也有影响：各种临床状况导致本研究解决的视觉处理的所有阶段都存在缺陷，影响个人在混乱的场景中定位重要信息、感知和识别对象以及整合眼睛运动中的信息的能力。然而，为了将这些发现应用于临床人群，建议中概述的基础研究是必要的，以更充分地了解正常功能成年人的视觉位置是如何通过物体和眼睛的运动而更新的。

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