The role of object-based attention in motion perception

长期的目标是研究注意力和运动加工之间的相互作用，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。指导性假说：视觉注意力主要是“基于表面的”。它针对的是整个表面，而不是特定的特征，有助于形成有注意的表面的连贯表示，同时抑制无人注意的视觉前沿。这一假说还认为：即使注意力被引导到表面，这是一组由自下而上的机制组合在一起的特征，但通过从表面机制到从属于它们的特征分析器的反馈连接，在较低级别的单位中间接地促进了加工。靶向运动处理允许利用运动后效应(MAE)，这是测量运动刺激处理的强大工具。具体目的1.分离负责注意调节运动加工的易化机制的影响。这些效应的相对强度，以及它们对所关注刺激的低水平特性的依赖性，将通过测量对MAE的注意效应来研究。具体目的2.对运动加工的注意效应，从而对MAE的注意效应是由于对整个表面的选择性增强，而不是特定的运动成分的假设，将被检验。注意效应的差异将被研究，当注意力在刺激的某一方面上执行一项无关的、非运动的任务时，该刺激位于与适应运动相同的表面上，或者在不同的表面上。具体目标3.将检验注意力参与表面形成的假设。将使用特殊的刺激，其中局部运动方向由全局表面形成来修改。如果注意涉及表面形成，当适应过程中注意力被中心任务分散时，正常的全局MAE方向将改变为局部方向。

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.