Item

Abstract

Knowledge underlying everyday navigation is distinguished into route and survey knowledge (Golledge 1999). Route knowledge allows re-combining and navigating familiar routes. Survey knowledge is used for pointing to distant locations or finding novel shortcuts. We show that within one’s city of residency route and survey knowledge root in separate memories of the same environment and are represented within different reference frames. Twenty-six Tu¨bingen residents who lived there for seven years in
average faced a photo- realistic virtual model of Tübingen and completed a survey task in which they pointed to familiar target locations from various locations and orientations. Each participant’s performance was most accurate when facing north, and errors increased as participants’ deviation from a north-facing orientation
increased. This suggests that participants’ survey knowledge was organized within a single, north-oriented reference frame. One week later, 23 of the same participants conducted route knowledge tasks comprising of the very same start and goal locations used in the survey task before. Now participants did not point to a goal location, but used arrow keys of a keyboard to enter
route decisions along an imagined route leading to the goal.
Deviations from the correct number of left, straight, etc. decisions and response latencies were completely uncorrelated to errors and latencies in pointing. This suggests that participants employed different and independent representations for the matched route and survey tasks. Furthermore, participants made fewer route errors when asked to respond from an imagined horizontal walking perspective rather than from an imagined constant aerial perspective which replaced left, straight, right decisions by up, left, right, down as in a map with the
order tasks balanced. This performance advantage suggests that participants did not rely on the single, north-up reference used for pointing. Route and survey knowledge were organized along different reference frames. We conclude that our participants’ route knowledge employed
multiple local reference frames acquired from navigation whereas their survey knowledge relied on a single north-oriented reference frame learned from maps. Within their everyday environment, people seem to use map or navigation-based knowledge according to which best suits the task.