Path integration, rather than being suppressed, used to update spatial views in familiar environments with landmarks always available

Abstract

This project, following the elegant paradigm developed by Zhao and Warren (2015b), investigated how self-motion cues and landmarks are used during navigation in a familiar environment with constantly available landmarks. Participants learned the location of a specific object. After completing one outbound path starting from the object, participants pointed to the object (homing). In Experiments 1 and 1b, there were landmarks throughout the first 9 trials. On some later trials, the landmarks were presented during the outbound path but unexpectedly removed during homing (catch trials). On the last trials, there were no landmarks throughout (baseline trials). Experiments 2-3 were similar but added two identical objects (the original one and the distractor one that was rotated from the original one) during homing on the catch and baseline trials. Experiment 4 added two groups of landmarks (the original and the rotated distractor) instead of two targets. The results showed homing angular error on the first catch trial was significantly larger than the matched baseline trial in Experiments 1 and 1b. In contrast, the proportion of participants who correctly recognized the original object or landmarks was comparable on the first catch and the matched baseline trial in Experiment 2-4. These results indicated that self-motion cues might be used to update spatial views of the familiar environment during locomotion. Although an unexpected removal of landmarks creates mismatches between updated and real views, impairing homing performance, the updated spatial views can remove the ambiguous targets or landmarks in the familiar environment.