Mid-level mechanisms of surface and binocular perception

描述（由申请人提供）：视网膜图像本身是不完整和模糊的，因为单独实体的图像重叠。但是早期的视觉机制并不具备将重叠的2-D视网膜图像解析成不同的3-D实体的能力。解析这些图像的工作福尔斯在中间层机制上，其主要作用是将不同的实体表示为单独的表面。然后，所表示的表面信息作为输入到“是什么”和“在哪里”系统，这两个系统分别构成了我们对物体和空间的3D感知。因此，中级机制不仅仅是早期和晚期视觉机制之间的简单信息“管道”，而且在确定所传达的视觉信息的质量和可靠性方面发挥着至关重要的作用。与视觉加工的其他方面相比，对中层机制的了解较少。最大的挑战之一是发现通常零碎和模糊的视网膜信息是如何转化为可靠的表面表示的，大概是通过扩展操作。有时，当属于同一实体的图像由于遮挡而被分成多个部分时，需要进行表面插值操作以将这些部分整合到全局表面中。此外，来自两只眼睛的有助于这些操作的输入在内容和位置上可能是不同的。在面对无数的视觉输入的复杂性，它进一步提出，中级机制必须依赖于内部的假设（感知规则）和反馈，从更高的视觉水平的指导，在代表表面。但这些操作是如何完成的仍不清楚。为了弥补这一点，本建议采用人类心理物理学方法，通过关注三个具体目标来调查上述问题。目的1研究如何展开的操作表示表面的纹理图案，这是更复杂的比表示无纹理表面。提出了减少编码冗余的原则，该原则控制了扩展操作，使得全局表面表示操作是有效的，但容易导致分辨率差。后者可能是众所周知的“拥挤效应”现象的基础之一。目的2研究纹理曲面插值运算。在认识到注意力和客体知识的作用后，本研究探讨了这些自上而下的因素如何影响表面整合。目的3研究中层机制的长期可塑性。知觉学习实验将进行，以揭示如何广泛的培训修改的知觉规则实施的中级。这个建议的长期目标是推进我们对视觉信息如何被处理和由中级机制表示的知识。这些知识有助于我们更好地了解人类如何感知视觉世界，并为弱视，斜视和衰老相关的视觉功能障碍的行为诊断和治疗提供临床基础。

DESCRIPTION (provided by applicant): Retinal images are inherently fragmentary and ambiguous because images of separate entities overlap. But the early visual mechanisms are not equipped to parse the overlapping 2-D retinal images into distinct 3-D entities. The job of parsing these images falls on the mid-level mechanisms, whose main role is to represent the distinct entities as separate surfaces. The represented surface information then serves as inputs to the WHAT and WHERE systems that underlie our 3-D perception of objects and space, respectively. As such, the mid-level mechanisms are not just simple "conduits" of information between early and late level visual mechanisms but play a crucial role in determining the quality and reliability of the visual information conveyed. Compared to other aspects of visual processing, less is known about the mid-level mechanisms. One of the biggest challenges is to discover how the often fragmentary and ambiguous retinal information is transformed into reliable surface representations, presumably, through a spreading-in operation. At times, when an image belonging to the same entity is broken into parts due to occlusion, a surface interpolation operation is required to integrate the parts into a global surface. Moreover, inputs from the two eyes that contribute to these operations can be disparate in content and location. In the face of the myriad complexities of the visual inputs, it is further proposed that the mid-level mechanisms must rely on internal assumptions (perceptual rules) and feedbacks from the higher visual levels for guidance in representing surfaces. But how these operations are accomplished is still unclear. Remedying it, this proposal uses the human psychophysical approach to investigate the above issues by focusing on three specific aims. Aim 1 investigates how the spreading-in operation represents surfaces with texture patterns, which is more complex than representing texture-free surfaces. It is proposed the principle of reducing coding redundancy that governs the spreading-in operation causes the global surface representation operation to be efficient but prone to poor resolution. The latter could be one basis of the well-known "crowding effect" phenomenon. Aim 2 investigates the texture-surface interpolation operation. Cognizant of the roles of attention and object knowledge, the research investigates how these top-down factors influence surface integration. Aim 3 investigates the long-term plasticity of the mid-level mechanisms. Perceptual learning experiments will be conducted to reveal how extensive training modifies the perceptual rules implemented at the mid-level. The long-term goal of this proposal is to advance our knowledge of how visual information is processed and represented by the mid-level mechanisms. This knowledge helps us better understand how humans perceive the visual world, and provides a clinical basis for behavioral diagnoses and treatments of visual dysfunctions related to amblyopia, strabismus and aging.