Locomotion, incidental learning, and the selection of spatial reference systems.

In three experiments, we examined the effects of locomotion and incidental learning on the formation of spatial memories. Participants learned the locations of objects in a room and then made judgments of relative direction, using their memories (e.g., "Imagine you are standing at the clock, facing the jar. Point to the book"). The experiments manipulated the number of headings experienced, the amount of interaction with the objects, and whether the participants were informed that their memories of the layout would be tested. When participants were required to maintain a constant body orientation during learning (Experiment 1), they represented the layout in terms of a single reference direction parallel to that orientation. When they were allowed to move freely in the room (Experiment 2), they seemed to use two orthogonal reference axes aligned with the walls of the enclosing room. Extensive movement under incidental learning conditions (Experiment 3) yielded a mixture of these two encoding strategies across participants. There was no evidence that locomotion, interaction with objects, or incidental learning led to the formation of spatial memories that differed from those formed from static viewing.