Basic and subordinate level categorizations of real-world scenes.

Previous research has tended to study the diagnostic information that facilitates scene categorization at a particular level of detail (e.g., a basic level: a classroom, a restaurant, etc.). However, scenes can be categorized at different levels of specificity (e.g., a classroom could more specifically be categorized as a lecture theatre). Here, we examined whether diagnostic information for scene categorization differed in nature and location as a function of the level of specificity. Participants were presented grey-scale scenes in four basic-level categories, with each category having exemplars from a further four subcategories. Participants categorized each scene either at a basic (e.g., classroom) or subordinate (e.g., lecture theatre) level in a 4AFC task. Critically, participants viewed scenes through a gaze-contingent window that presented full-resolution information to the fovea and low-passed information in the periphery. Participants therefore always had access to a scene’s coarse, spatial-layout, while finer, local details were only available through fixation. Analyzed behavior and fixation data showed that in most of the scene categories, the distribution of fixations differed significantly between basic and subordinate tasks. The results therefore suggest that the diagnostic information required for scene categorization changes in nature and location as a function of task specificity.