Spatial memory and large-scale ecological environments

Spatial memory is a necessary prerequisite of most everyday activities. We usually define “spatial” that information useful to locate objects and to interact with them. Therefore, it is “spatial” information about relational and metric properties, such as relative positions (e.g., left/right), distance, size, orientation, as well as dynamic properties, such as velocity and strength. Clearly, the ability to navigate in the environment requires an understanding of all these properties and a representation in memory of structured information. To organize spatial memory, egocentric (i.e. based on body’s position) or allocentric (i.e. based on external positions) frames of reference are used. Although research on spatial memory has a long history, in the majority of the cases experimental settings and procedures are restricted to laboratory situations, and the results are typically generalized to real world contexts. Consequently, little is known on the characteristics of spatial memory based on bodily interactions with large-scale everyday environments. In this paper we review evidence about laboratory-based and environment-based research on spatial memory. Further, a research is presented that investigated whether familiarity with a large-scale regular environment affects the spatial frames of reference necessary to represent it in memory. It was tested the hypothesis that familiarity facilitates an allocentric representation of the environment. Familiar and unfamiliar participants had to study 5 triads of buildings by walking along a path surrounding each triad. Afterwards, they had to provide relative distance judgments in relation either to their body (egocentric) or external buildings (allocentric). Results showed that familiar participants were more accurate than unfamiliar participants in the allocentric judgments and faster on the whole. Unfamiliar participants performed similarly in both judgments and were better than familiar participants in the egocentric judgments. These findings suggest that when the environment is familiar and regular it is represented on the basis of allocentric frames of reference. The results are discussed in relation to models of spatial memory that emphasize the importance of experience and of the geometric structure.