Measures of Subjective Variables in Visual Cognition

当人们被要求做一些涉及视觉的认知任务时，比如想象一个物体或在一个大的视觉阵列中搜索一个特定的物体，众所周知，某些物理上可测量的、“客观”的方面，比如它的复杂性，会影响人们完成任务的方式。此外，主观方面，那些不能用身体测量的方面，如熟悉度或意义，也会影响人们的表现。很少有实验能把客观变量和主观变量充分地分离开来，以至于人们能确切地说出哪些变量是特定实验效果的基础。本研究项目中的实验将从客观变量中分离主观变量，并将检查主观变量在一系列基于视觉的认知任务中的作用，包括图像任务，搜索任务和感知逆转任务。这些任务都可能受到观看者关于要想象或操纵的形状结构的知识的影响。该研究的基础是，视觉认知中的主观效应是由观看者对构成形状的特定成分和这些成分的相对位置的结构知识介导的；结构知识越多，图像处理、搜索和扫描的速度就越快，因此，观看者的表现也就越高效。实验将测试这一概念，并在此过程中，将尝试将结构知识的构造与整体处理的构造分离开来，并检查空间注意与结构知识之间的相互作用。最后，研究将发展任务的功能分类，以确定产生主观影响的处理类型。假设是，当任务允许心理操作可分类的、基本的形状，而不需要操作详细的特定形状时，这些效果就会发生。这种任务分类法，连同结构知识的构建，可能有助于识别视觉认知的“功能性词汇”，这些词汇在现实世界中需要速度和准确性的任务中使用。

When people are asked to do a number of cognitive tasks involving vision, such as imaging an object or searching for a particular object in a large visual array, it is well known that certain physically measurable, "objective" aspects of the display, such as its complexity, influence how people do the tasks. In addition, subjective aspects, ones that cannot be measured physically, such as familiarity or meaning, also influence people's performance. Few experiments have separated objective from subjective variables sufficiently that one can tell conclusively which ones underly particular experimental effects. The experiments in this research project will isolate subjective variables from objective variables and will examine the role of subjective variables in a series of visually-based cognitive tasks, including imagery tasks, search tasks, and perceptual reversal tasks. These tasks are all potentially influenced by the viewer's knowledge regarding the structure of the shape to be imagined or manipulated. The research flows from the notion that subjective effects in visual cognition are mediated by the viewer's structural knowledge regarding the particular components from which a shape is constructed and the relative locations of these components; the greater the structural knowledge, the faster images can be manipulated, searched, and scanned, and hence, the more efficient the viewer's performance. The experiments will test this notion and, in the process, will attempt to separate the construct of structural knowledge from that of wholistic processing and to examine the interaction between spatial attention and structural knowledge. Finally, the research will develop a functional taxonomy of tasks to identify the types of processing that yield subjective effects. The hypothesis is that these effects will occur when tasks permit the mental manipulation of categorizable, basic- level shapes rather than requiring manipulation of detailed particular shapes. This taxonomy of tasks, together with the construct of structural knowledge, may be useful in identifying the "functional vocabulary" of visual cognition that is employed in real-world tasks requiring speed and accuracy.