Making a Scene: How Visual Features Contribute to Scene Representation
Jonathan S. Cant
University of Toronto Scarborough

It has previously been demonstrated that the scene-sensitive parahippocampal place area (PPA) is more active for judgments of the surface texture and material properties of single isolated objects, compared to judgments of object shape. On the surface, this appears inconsistent with the view that PPA is specialized for processing scenes, since the single objects were not presented in the context of a scene. However, surface texture (and the material-properties signaled by texture) is important in scene processing as it can be used to aid in image segmentation, can contribute to the recognition of scene identity, and can provide affordance-related cues relevant for navigation. Thus, the finding that attending to object texture and material activates PPA may be better interpreted as evidence that PPA utilizes multiple visual features, in addition to its well-known role in processing global spatial features such as structural geometry, when representing scenes. Building on this observation, in this talk I will present the results of several studies examining the contribution of different visual features to scene representation in human occipito-temporal cortex. Specifically, I will present results investigating: 1) whether scene-selective cortex is more sensitive to processing scene, compared with object, texture; 2) whether the processing of different scene features (i.e., scene geometry/layout and scene texture/material) is mediated by shared or distinct neuronal mechanisms in scene-selective cortex; 3) whether the importance of scene layout and scene texture varies according the type of scene category being perceived (i.e., open vs. closed scenes, and natural vs. manufactured scenes); 4) how task context influences the representation of scenes in occipito-temporal cortex; and 5) the relation between object-ensemble perception and texture perception in scene processing. Finally, given that we do not typically perceive scenes devoid of objects (and in turn, we do not perceive objects outside of the context of a scene), I will present some recent results investigating interactions between scene and object perception (i.e., does global/scene perception interfere with local/object perception, or vice versa?). Taken together, these results will demonstrate that multiple visual features are represented in human scene-selective cortex, and that this representation is flexible, as the importance of different scene features varies according to perceived scene category and the goals of the observer. Moreover, the finding that object-scene interactions are influenced by both global and local image features may explain how one is able to perceive both the “entire forest” and the “individual trees” from a visual scene.