Abstract
The guidance of attention toward task-relevant objects during visual search often relies on a target template representation. In addition, many searches are categorical, where the goal of search is to find any item belonging to a category (Yang & Zelinsky, 2009). In the present study, we investigated the extent to which these categorical template representations are biased toward recently viewed category exemplars. Participants first completed an exposure task in which they viewed pictures of objects from common categories and classified them as natural or artifact. Critically, each exemplar from a given category always appeared in one color (e.g., all cars were blue). After completing the categorization task, participants performed four blocks of visual search. They saw a label specifying the target category and searched for the target picture within an array of objects. The target picture matched (e.g., a different blue car) or mismatched (e.g., a red car) the color of the previously viewed exemplars. Searches were more efficient for matching compared with mismatching color exemplars, and this effect reliably diminished across search blocks, as participants accrued more trials of search with exemplars of both colors. Moreover, eye-tracking results demonstrated that this effect was due to more efficient guidance to the target, as evidenced by faster first fixations on the target object when it matched compared with when it mismatched the previously viewed exemplar color. These results suggest that well-established category representations guiding visual search are constantly updated to reflect recent visual regularities within a category. The relationship between these findings and general theories of category structure will be discussed.