C. Freksa et al. (Eds.): Spatial Cognition IV, LNAI 3343, pp. 245 – 258, 2005. © Springer-Verlag Berlin Heidelberg 2005 Imagined Perspective–Changing Within and Across Novel Environments Marios N. Avraamides 1 and Jonathan W. Kelly 2 1 Department of Psychology, University of Cyprus, P.O. Box 20537, 1678 Nicosia, Cyprus mariosav@ucy.ac.cy 2 Department of Psychology, University of California, Santa Barbara, CA 93106-9660, USA j_kelly@psych.ucsb.edu Abstract. Results suggesting that changing perspective and switching across spatial environments held in memory are processes that take place in parallel were obtained from a task-switching experiment. Participants learned layouts of objects in two virtual rooms and then were asked to use their memories to lo- cate the objects from various imagined viewing perspectives. Results revealed that, even after experiencing multiple perspectives, participants maintained viewpoint-dependent memories for the layouts, and that the latencies for chang- ing perspective within and across environments followed a different pattern de- pending on whether participants imagined adopting the preferred view. 1 Introduction Everyday tasks, such as giving and taking route directions, often require imagined navigation within spaces that are not perceptually available. In order to comprehend route directions, for example, we often perform a mental simulation of our movement, imagining ourselves passing through various neighborhoods and intersections that are held in memory. Past research on spatial memory has suggested that we represent the world in our memory in a hierarchical fashion. That is, we parse the world into smaller meaningful units, creating thus a collection of separate representations (Hirtle & Jonides, 1985; McNamara, 1986). A hierarchy of representations is then created by linking these rep- resentations to higher-order representations (e.g., the separate representations for the rooms of a building are connected to a representation for the building). Supporting accounts of hierarchical organization of spatial memory, a number of studies (e.g., Stevens & Coupe, 1978) have shown that our spatial memory is often biased by the use of information stored at a superordinate level in the hierarchy. Furthermore, other studies have provided evidence for the presence of multiple separate spatial representations. McNamara (1986), for example, has demonstrated that spatial judgments about targets in the same spatial region are faster than judgments about targets in different spatial regions, suggesting that the knowledge is organized in separate spatial representations.