Navigating without vision: A role for spatial language?

Purpose: We are interested in how well geometric information about the layout of a building can be conveyed by spatial language. Can people explore and learn building layouts nonvisually using verbal descriptions? Does learning strategy or navigation performance differ as a function of the amount of verbal information provided? In this study, we compared performance on environmental learning and route finding ability when the available information about layout geometry was conveyed in three different verbal conditions. 1) Local: verbal information describes the layout geometry at the user's current position. 2) Enhanced Local: adds "look ahead" information by giving distance and connectivity information about adjacent intersections. 3) Global: adds a verbal description about the global geometry of the layout. Methods: 8 blindfolded participants trained and tested on all conditions. The participant's task was to use the verbal descriptions to explore the floor and find 4 target locations, indicated by an auditory cue. At each corridor intersection a description was given and participants chose which direction to walk (guided by the experimenter to avoid obstacles). After a fixed amount of training, participants' knowledge of the floor plan was tested by finding routes between pairs of targets. Results: Preliminary results show no significant differences between the verbal conditions. Overall target localization accuracy (M=79%, SE=4.82) was significantly above chance (∼2%, defined as 1 over the number of possible target locations), t(71)=15.87, p<.0001. The overall mean for optimal path selection (the shortest possible path between targets over the route taken) was (M=91%, SE=3.01) indicating route efficiency was high for all conditions. Future analysis will address if the amount of verbal information during learning affects exploration strategy. Conclusions: The results support the notion that spatial language can be efficiently used to learn and navigate an environment.