Spatial Perception is Continuously Constrained by Goals and Memories

Perceptual variables such as perceived distance contain information about future actions. Often our goals involve the integration of another’s goals, such as lifting heavy objects together. The purpose of this study was to investigate how another’s actions might influence one’s own goal-oriented perceptions, specifically, verbal distance estimates. Using a within-subject paradigm, we replicated a well-known finding that carrying a weighted backpack results in larger distance estimates relative to not carrying a backpack. In a crucial second condition, this effect was reversed: distance estimates were significantly greater when not carrying a weighted backpack than when carrying a backpack. In this condition, participants provided distance estimates while wearing a weighted backpack during the first phase and then gave estimates while not wearing a backpack, but following an experimenter wearing a weighted backpack in the second phase. Three additional conditions systematically documented how the observations of another’s actions influenced distance estimates.