Predictive Cues and Multiple Fixation Search

人类的视觉搜索包括仔细观察视觉场景，通过眼球运动将眼睛的中心，即中心凹定位到感兴趣的区域。中心凹的高分辨率允许以更精细的细节处理视觉世界。此外，视觉搜索还涉及关注视觉场景中的不同点，而不依赖于眼睛的位置。当存在与感兴趣目标共同出现的其他对象(线索)时，视觉搜索通常也是便利的。当目标物体出现在意想不到的位置时，人们往往很难找到目标。几十年来，研究人员一直在研究这种预测性线索如何有助于人类在各种任务中的搜索性能。然而，这些研究中的大多数都是为了防止人类进行眼球运动，以孤立地研究隐蔽视觉注意的机制。人们对线索和背景帮助人们自由移动眼睛的自然行为的搜索机制知之甚少。在这项研究中，研究人员试图了解人类利用线索和背景来计划眼球运动和隐蔽注意力以优化视觉搜索的机制。他们将开发在计算机上实现的数学模型，以模拟人脑调节视觉搜索的过程。这项研究将有助于更好地理解线索和背景有助于视觉搜索的机制，并预测在视觉搜索中使用预测性线索带来的感知判断的准确性方面的好处。在人群中寻找朋友，在停车场寻找一辆车，在客厅里寻找你的房子钥匙，这些都是人类日常进行视觉搜索的例子。这项研究是理解人类在自然环境中进行视觉搜索的必要步骤。视觉搜索还包括生命关键任务，如在医学图像中发现肿瘤或在行李x光中发现潜在危险物体。这项研究还将有可能为生命关键搜索任务的效率提供见解。最后，这项研究可能有助于更好地评估注意障碍患者(例如，半忽视)在自然主义搜索行为中的预期缺陷。这项工作将整合各级(高中实习生、本科生和研究生)的研究和教育活动，通过开发一个网站，使世界各地的学生和研究人员能够通过互联网浏览器输入实验数据，并测试各种计算机模型。

Human visual search involves scrutinizing the visual scene by making eye movements to orient the center of the eye, the fovea, to regions of interest. The high resolution of the fovea allows for processing of the visual world with finer detail. In addition, visual search also involves attending to different points in the visual scene independent of the eye position. Visual search is also often facilitated when there are other objects (cues) that co-occur with the target of interest. When the target object appears at unexpected locations, people often have difficulty finding the target. Researchers have for decades studied how such predictive cues benefit human search performance in a variety of tasks. However, most of these studies were designed to prevent humans from making eye movements to study the mechanisms of covert visual attention in isolation. Little is known about the mechanisms by which cues and context aid search in natural behavior where people are free to move their eyes. In this proposal, the investigators seek to understand the mechanisms by which humans use cues and context to plan eye movements and covert attention to optimize visual search. They will develop mathematical models implemented on computers to mimic the processes by which the human brain mediates visual search. The research will allow for a better understanding of the mechanisms by which cues and context aid visual search and also predict the benefits in accuracy of perceptual judgments brought by the use of predictive cues in visual search. Looking for a friend in a crowd, a car in a parking lot, and your house keys in the living room are all examples of visual searches that humans do on a daily basis. The proposed research is a necessary step to understand human visual search in the natural environment. Visual search also include life-critical tasks such as finding a tumor in a medical image or a potentially dangerous object in a baggage x-ray. This research will also have the potential to provide insights into the efficiency in life-critical search tasks. Finally, the research can potentially contribute to better assessments of the expected deficits of patients with attentional disorders (e.g., hemi-neglect) in naturalistic search behavior. The work will integrate research and educational activities at all levels (high school interns, undergraduate, and graduate) through the development of a website that enables students and researchers worldwide to enter experimental data through an internet browser and test the various computer models.