© 1999 Kluwer Academic Publishers. Printed in the Netherlands. Human navigation ability: Tests of the encoding-error model of path integration

Abstract. This paper tests the generality and implications of an “encoding-error ” model (Fujita et al. 1993) of humans ’ ability to keep track of their position in space in the absence of visual cues (i.e., by nonvisual path integration). The model proposes that when people undergo nonvisually guided travel, they encode the distances and turns that they experience, and their errors reflect systematic inaccuracies in the encoding process. Thus when people try to return to the origin of travel, they base their response on mis-encoded values of the outbound distances and turns. The two experiments reported here addressed three issues related to the model: (i) whether path integration is context-dependent and if so, how rapidly it adapts to recently experienced distances and turns; (ii) whether effects of experience can be specifically attributed to changes in the encoding process, and if so, what changes; and (iii) whether the encoding process represents distances and turns in the individual paths without considering their spatial relationship to one another (i.e., an object-centered representation). Testing these issues allows us to evaluate and develop the model. Subjects who were blindfolded or had restricted vision were led through two legs of a triangle and the turn between, then tried to return to the origin. Paths varied in whethe