| The goal of the current studies is to investigate conditions in which locomotion about a scene automatically updates a person's representation of the scene to be spatially consistent with the person's perspective of the scene after moving. A review of the spatial updating literature revealed to us several possible factors that could contribute to observer movement leading to viewpoint independent recognition of scenes: range of angles between encoding and judging a scene, scene set size, and the length of retention between encoding and judging a scene. In Experiments la and 1b, participants memorized a scene (11-, and 10-objects) from a single perspective. Then, either the scene was rotated or the participants moved (0° to 360° in 40° and 36° increments) around the scene, and participants judged whether the inter-object distances had changed. Regardless of whether the scene was rotated or the observer moved, RT increased with greater angular distance between judged and encoded views. Then, in Experiment 2, we examined whether automatic spatial updating depends on the number of objects in a scene. Participants memorized 5- and 10-object scenes, then either the scene was rotated or the participants moved (0° to 180°) around the scene, and participants judged what object had moved. Regardless of the set size, RT increased with angular distance. Studies that found evidence of spatial updating have used short-term retention paradigms whereas in our previous studies we used a long-term retention paradigm. Thus, in Experiment 3 we examined short-term scene recognition with scenes of varying set sizes (4-, 6-, 8, and 10-objects). Participants briefly viewed (3 s) a scene on each trial and immediately either moved around the scene and made scene recognition judgments for observer movement trials or immediately made scene recognition judgments for scene movement trials. Regardless of set size, RT increased and accuracy decreased with increasing angular distance. Research suggests that a short delay (as brief as 10 s) between encoding a scene and moving might impair automatic spatial updating. Thus, in Experiment 4 we examined whether automatic spatial updating depends on scene retention duration by varying the time between encoding a scene and moving about a scene (0 s, 6 s, and 12 s). Regardless of the delay, accuracy decreased and RT increased with angular distance for both observer and scene movement. Research suggests that representations of scenes could be updated either offline, after a period of movement is completed utilizing enduring representation in long-term memory, or online by continually keep track of objects in the environment on a moment-to-moment basis. In Experiment 5 we compared offline and online spatial updating following movement around a 5-object scene. Scene recognition judgments showed viewpoint-dependent patterns for both groups, but the offline group performed significantly faster and more accurately than the online group, suggesting that reliance on egocentric representations when making scene recognition judgments does not always lead to enhanced recognition. Overall, our data show that observer movement does not automatically update representations of spatial layouts and raise important questions about the effects of duration limitations, encoding frames of reference, and encoding points of view on the automatic spatial updating of representations of scenes. |
