Figure 1.

A, Each trial began with a 2 s stationary wait period during which the subject viewed the environment. Once the target object appeared, the subject had 5 s of encoding, during which the subject (in the virtual reality environment) was automatically rotated toward and then driven to the target location. This was repeated from a different starting point such that there were two encoding trials for each target location. After the encoding trials, subjects were transported to a new starting point for the test phase and asked to drive themselves back to the target location and respond by pressing a button. Feedback was provided by displaying a map of the target and response location, along with game points that correlated with distance error. B, We computed an MS based on the accuracy percentile with respect to the chance distribution of responses for each target location. C, Target locations were categorized as being boundary or inner by dividing the rectangular environment into two equal areas with equal aspect ratios. D, Subjectwise distributions of memory scores for boundary and inner trials, which indicate that subjects performed better on boundary trials overall.