Inhibitory and Facilitatory Processing in Image Segregation

摘要：玛丽·彼得森在感知视觉世界的过程中，最早的步骤之一就是将视觉输入分为人物和背景。当视野中的两个相邻区域共享一条等高线时，一个区域通常被视为图形，而另一个区域似乎是地面。人物被赋予了明确的形状，而地面在接近他们与人物共享的轮廓时是没有形状的。传统上认为，图地分离是基于低层次线索，如深度线索和结构线索（即对称、凸性、封闭或相对面积小）。这些低级线索被认为在记忆表征被访问之前起作用。与传统的观点相反，最近的研究表明，在知觉加工过程中，物体结构的记忆比传统模型所假设的更早被获取。此外，这些对象记忆对图像分离也有影响。这些发现与一些模型相一致，这些模型允许更高层次的过程，比如那些访问对象结构记忆的过程，影响图形-背景阶段的处理。提出的实验测试了一个独特模型的可行性，该模型不认为图-地分离是视觉过程层次结构中的一个阶段。相反，它认为图地分离是在轮廓两侧操作的早期图像分离过程之间相互作用的一个可能结果。该模型需要在轮廓的同一侧操作的过程之间的促进和在轮廓的相反一侧操作的过程之间的抑制。除了考虑到表明物体结构的记忆可以影响图像分离的证据外，该模型还明确解释了三种以前未被探索的分离现象。这些现象是：(1)物体只有在用图形来描绘的时候才能被有意识地认识，而不是用根据来描绘的时候；(2)地面没有形状；(3)图形-图形结果（其中轮廓两侧的区域似乎具有明确的形状）可以被感知，尽管图形-背景结果往往是首选的。当前提案中的实验构成了对这个新模型中提出的抑制的有力检验。计划中的实验使用启动范式来评估在知觉加工过程中，在最终确定为基础的区域上操作的过程是否首先被激活，然后被抑制。本研究中的其他实验探讨了隔离介导的抑制与一种被称为负启动的注意现象之间的关系。提出的实验有望提供证据，这将对区分高级过程如何影响早期视觉过程的竞争模型至关重要-这些过程是感知和行动的基础。此外，这些实验将整合两个以前完全不同的研究领域——注意力抑制和图像分离。

Award AbstractPI: Mary PetersonOne of the earliest steps in the process of perceiving the visual world is to segregate the visual input into figures and backgrounds. When two adjacent regions in the visual field share a contour, one region is typically seen as the figure, and the other region appears to be the ground. Figures are endowed with a definite shape, whereas grounds are shapeless near the contours they share with figures. It has traditionally been assumed that figure-ground segregation is based on low-level cues, such as depth cues and configural cues (i.e., symmetry, convexity, enclosure or smallness of relative area). These low-level cues are thought to operate before memory representations are accessed. Contrary to the traditional view, recent research indicates that memories of object structure are accessed earlier in the course of perceptual processing than assumed on the traditional model. Furthermore, these object memories exert an influence on image segregation. These findings are consistent with a number of models that allow higher-level processes, such as those accessing memories of object structure, to influence processing at a figure-ground stage. The proposed experiments test the viability of a unique model that does not consider figure-ground segregation to be a stage in the hierarchy of visual processes. Instead, it considers figure-ground segregation to be one possible outcome of the interactions among early image segregation processes operating on both sides of a contour. The model entails facilitation between processes operating on the same side of a contour and inhibition between processes operating on opposite sides of a contour. In addition to accounting for the evidence indicating that memories of object structure can affect image segregation, this model explicitly accounts for three previously unexplored segregation phenomena. Those phenomena are: (1) objects can be recognized consciously only when they are depicted by figures, not when they are depicted by grounds; (2) grounds are shapeless; (3) figure-figure outcomes (in which the regions on both sides of a contour appear to have a definite shape) can be perceived, although figure-ground outcomes tend to be preferred. The experiments in the current proposal constitute a strong test of the inhibition proposed in this new model. The planned experiments use a priming paradigm to assess whether processes operating on regions ultimately determined to be grounds are first activated and then inhibited in the course of perceptual processing. Other experiments in the proposal explore the relationship between segregation-mediated inhibition and an attentional phenomenon, called negative priming. The proposed experiments promise to provide evidence that will be critical for distinguishing among competing models of how high-level processes affect the earliest visual processes -- those processes that are fundamental to perception and action. In addition, these experiments will integrate two formerly disparate areas of study -- attentional inhibition and image segregation.