The role of object-based attention in motion perception

广泛的、长期的目标是研究注意力和运动处理之间的相互作用，使人们能够有效地整合、分割和保持对运动表面的统一感知。指导性假设：视觉注意主要是“基于表面的”。它指向整个表面，而不是特定的特征，有助于形成一个连贯的表象，同时抑制无人看管的视觉前沿。这一假设还认为：即使注意力被引导到一个表面，即由自下而上机制聚集在一起的特征群，通过从表面机制到为其服务的特征分析器的反馈连接，也间接地促进了较低层次单元的处理。目标运动处理可以利用运动后效应（MAE）这一测量运动刺激处理的有力工具。具体目标1。分离负责运动处理的注意调节的促进机制的影响。这些效应的相对强度，以及它们对被注意刺激的低水平特性的依赖，将通过测量对MAE的注意效应来研究。具体目标2。关于注意对运动处理的影响，即对MAE的影响，是由于整个表面的选择性增强，而不是特定的运动成分，这一假设将被测试。注意效应的差异将在以下两种情况下进行研究：当注意参与一个不相关的、非运动的任务时，该任务在刺激的一个方面上执行，该刺激与适应运动在同一表面上，或在不同的表面上。具体目标3。关于注意力参与表面形成的假设将被检验。将使用特殊的刺激，其中局部运动方向由全局表面形成修改。如果注意参与了表面的形成，那么在适应过程中，当注意力被中央凹任务分散时，通常全局的MAE方向会转变为局部的MAE方向。

The broad, long-term objective is to study the interaction between attention and motion processing that enables one to efficiently integrate, segment, and maintain a unified percept of moving surfaces. The guiding hypothesis: Visual attention is primarily "surface-based". It is directed to an entire surface, not particular features, facilitating the formation of a coherent representation of the attended surface, while suppressing unattended visual front. This hypothesis also holds that: even through attention is directed to a surface, which is a constellation of features chunked together by bottom-up mechanisms, processing is indirectly facilitated in lower-level units through feedback connections from surface-level mechanisms to the feature analyzers that subserves them. Targeting motion processing allows to take advantage of the motion after-effect (MAE), a powerful tool for measuring the processing of motion stimuli. SPECIFIC AIM 1. Isolate the effects of facilitatory mechanisms responsible for attentional modulation of motion processing. The relative strength of these effects, and their dependence on the low-level properties of the attended stimuli, will be investigated by measuring attentional effects on the MAE. SPECIFIC AIM 2. The hypothesis that attentional effects on motion processing, hence on the MAE, are due to selective enhancement of an entire surface, and not particular motion components, will be tested. Differences in attentional effects will be studied when attention is engaged in an irrelevant, non-motion task performed on an aspect of the stimulus which lies on the same surface as the adaption motion, or on a distinct surface. Specific aim 3. The hypothesis that attention is involved in the formation of surfaces will be tested. Special stimuli will be used, where local motion direction is modified by global surface formations. If attention is involved in surface formation, the normally global MAE direction will change to local when attention is distracted by a foveal task during adaptation.