Neural Correlates of Visual Object-Substitution Masking

描述（由申请人提供）：本研究计划将解决视觉注意力如何促进物体持久表征的构建这一基本问题，从而使人类和其他灵长类动物能够利用不再可用的信息。为了研究这个普遍问题，我们将研究最近引入的对象替代屏蔽范式。将提出两个一般性问题：(1)单个神经元的活动是否表明，即使没有加工到准确指导行为的程度，与行为相关的项目也会被注意力选择？(2)在神经活动的瞬间调节中，是否可以观察到一个目标被随后的掩膜所取代？物体替代掩蔽已被证明与注意力如何在视觉环境中部署直接相关，因为它只在视野中的物品之间存在强烈竞争时才会被观察到，例如在视觉搜索任务中，并且可以通过阻止对目标位置的注意来减少或消除。因此，这个项目中的实验将要求猴子在相似的干扰物形状中寻找目标形状。在一定比例的实验中，目标和几个干扰物将被四个圆点包围，这些圆点在物体本身消失后仍然可见，从而有效地掩盖了物体。对注意力和这种新形式的掩蔽之间的相互作用的进一步了解可能最终帮助我们理解正常认知处理的障碍，如注意缺陷障碍。

DESCRIPTION (provided by applicant): This research proposal will address the fundamental issue of how visual attention contributes to the construction of enduring representations of objects allowing humans and other primates to make use of information that is no longer available. To investigate this general issue, the recently introduced object-substitution masking paradigm will be studied. Two general questions will be asked: (1) Does the activity of single neurons suggest that behaviorally relevant items are selected by attention even though they are not processed to the point of accurately guiding behavior? (2) Can the substitution of a target by a subsequent mask be observed in the moment-to-moment modulation of neural activity? Object-substitution masking has been shown to be directly related to how attention is deployed in the visual environment because it is only observed when there is strong competition between items in the visual field, such as in visual search task, and can be reduced or eliminated by precuing attention to the target location. Thus, the experiments in this project will require monkeys to search for a target shape among similar distractor shapes. On a proportion of trials the target and several distractors will be presented surrounded by four dots that should effectively mask the items when they remain visible after the objects themselves disappear. An increased understanding of interactions between attention and this new form of masking may ultimately help us understand disorders of normal cognitive processing such as in attention deficit disorder.