Neural Visual Coding: Image to Object Representation

描述（由申请人提供）：有一些基本的视觉，我们不明白。日常经验告诉我们，即使物体很复杂，我们也可以感知到眼睛可以分辨的物体的每一个细节。但神经生理学证据表明，最详细的视觉信息只在早期处理阶段（V1和V2区）表现出来，那里的神经元具有固定在视网膜上的小感受野。这意味着每次眼睛移动到一个新的固定点时，一组不同的神经元被激活，每秒连续发生3-4次。如何从这些分散的反应中得到对物体的稳定的感知呢？这项申请提出了一项新的理论，该理论描述了视觉大脑中物体表征的出现及其在注意力部署中的作用。根据该理论，在LIP和纹外视区发现的感受野的重映射，以及最近在V1和V2中发现的图形-背景结构的重映射，具有共同的机制。拟议中的实验将使用非人类灵长类动物行为的单细胞记录。通过记录从顶叶和纹外视觉区，两个关键的预测理论将被测试。一个是感受野的重新映射，如经典的与扫视有关的观察，也应该发生在对物体运动的反应中。将测试几个用经典重映射范式发现重映射的领域，预计结果在不同领域之间会有所不同。第二个预测是以高电平记录的重映射信号（例如，顶骨区）和低水平（例如，区域V2）应该表现出特定的相关性。这将通过用两个微电极同时记录来测试。如果得到证实，这将是一个全面的视觉处理理论，包括图形-背景组织，基于对象的注意力和知觉稳定性的一步。

DESCRIPTION (provided by applicant): There is something basic about vision that we do not understand. Everyday experience tells us that we can perceive every detail of an object that our eyes can resolve, even if the object is complex. But neurophysiological evidence shows that the most detailed visual information is represented only at the early processing stages (areas V1 and V2), where neurons have small receptive fields that are fixed on the retinae. This means that a different set of neurons is activated every time the eyes move to a new fixation, which occurs continually 3-4 times per second. How can a stable percept of the object result from these scattered responses? This application proposes research to test a new theory that describes the emergence of object representations in the visual brain and its role in the deployment of attention. According to the theory, the remapping of receptive fields as found in LIP and extrastriate visual areas, and the remapping of figure-ground structure that was recently discovered in V1 and V2, have a common mechanism. The proposed experiments will use single-cell recordings in behaving non-human primates. By recording from parietal and extrastriate visual areas, two critical predictions of the theory will be tested. One is that remapping of receptive fields, as classically observed in connection with saccades, should also occur in response to object movements. Several areas where remapping has been found with the classic remapping paradigm will be tested, and results are expected to differ between areas. The second prediction is that the remapping signals recorded at high level (e.g., parietal area) and low level (e.g., area V2) should exhibit specific correlations. This will be tested by recordin simultaneously with two microelectrodes. If confirmed, this would be a step towards a comprehensive theory of visual processing that includes figure-ground organization, object-based attention, and perceptual stability.