Perceiving real-world viewpoint changes

Retinal images vary as observers move through the environment, but observers seem to have little difficulty recognizing objects and scenes across changes in view. Although real-world view changes can be produced both by object rotations (orientation changes) and by observer movements (viewpoint changes), research on recognition across views has relied exclusively on display rotations. However, research on spatial reasoning suggests a possible dissociation between orientation and viewpoint. Here we demonstrate that scene recognition in the real world depends on more than the retinal projection of the visible array; viewpoint changes have little effect on detection of layout changes, but equivalent orientation changes disrupt performance significantly. Findings from our three experiments suggest that scene recognition across view changes relies on a mechanism that updates a viewer-centered representation during observer movements, a mechanism not available for orientation changes. These results link findings from spatial tasks to work on object and scene recognition and highlight the importance of considering the mechanisms underlying recognition in real environments.