The effect of repetition priming on spatial memory during backtracking in a novel environment.

During wayfinding in a novel environment, we encounter many new places. Some of those places are encoded by our spatial memory. But how does the human brain "decides" which locations are more important than others, and how do backtracking and repetition priming enhances memorization of these scenes? In this work, we explore how backtracking improves encoding of encountered locations. We also check whether repetition priming helps with further memory enhancement. We recruited 20 adults. Each participant was guided through an unfamiliar indoor environment. The participants were instructed to remember the path, as they would need to backtrack by themselves. Two groups were defined: the first group performed a spatial memory test at the goal destination and after backtracking; the second group performed the test only after backtracking. The mean spatial memory scores of the first group improved significantly after backtracking: from 49.8 to 60.8%. The score of the second group was 62%. No difference was found in performance between the first group and the second group. Backtracking alone significantly improves spatial memory of visited places. Surprisingly, repetition priming does not further enhance memorization of these places. This result may suggest that spatial reasoning causes significant cognitive load that thwarts further improvement of spatial memory of locations.