The mechanisms of categorical influences on visual search

Abstract

In this article, we consider the issue of categorical influences on visual search performance. In order to compare the mechanisms of such influences, described in modern paradigms, we use two parameters: the accessibility of categorical information and the form of its representation. The parameter of accessibility concerns the temporal aspect: on which stage of a search task the participants have access to the categorical information. This information could be available during a search task or before it during the target presentation stage. The second parameter is a form of representation of categorical information. It could be represented directly as categorical knowledge, or indirectly by an object’s visual features. Our analysis shows the following: If categorical information is available only at the target demonstration stage and represented indirectly by visual features, then it influences visual search by recalling a prototype of a target category, the visual features of which then form a search template. If a category of a scene is also available, then it helps to choose the most relevant zones in a scene for search. Additional information of distractors’ categories will draw participants’ attention to the objects which are categorically similar to a target. Finally, if categorical information is available directly during the search stage, it influences our attention more than visual features. Therefore, we conclude that the mechanism of categorical influences on visual search depends on the amount of categorical information available to a participant. The more categorical information of objects and a scene is available to participants, the more it influences visual search performance.