Abstract
The action-specific account of perception states that a perceiver's ability to act influences the perception of the environment. For example, participants tend to perceive distances as farther when on hills than on flat planes (Stefanucci et al., 2005). This is known as the Distance-on-Hill (DoH) Effect. However, critics of the action-specific account of perception claim that such effects could be due to participants guessing the hypothesis and trying to comply with the experimental demands. The present studies explored the DoH effect to explore whether it is truly perceptual or due to response bias. Participants judged the distance to targets on a hill and on the flat ground in a virtual reality environment. They stood between the hill and a flat surface and saw a cone on each surface. They manipulated one of the cones with the goal of making both cones equidistant. For half the trials, participants manipulated the cone on the hill; for the other half, they manipulated the cone on the flat surface. First, we replicated the DoH effect that the distances on the hill appeared farther (p < .005). In a second study, we provided feedback on their responses ("Too far" or "Too close"). Despite this feedback, participants still judged cones on hills to be farther than on flat surfaces[T1] (p < .001). We also applied the El Greco fallacy: if the effects were truly perceptual, when judging cones on two hills against each other, the effects should cancel each other out, but if the effects were due to response bias, the effect of the hill should still emerge. As predicted, participants moved the cones similarly when both cones were on the hill and when both cones were on the flat surface (p=.72). This also furthers the evidence towards the DoH effect being perceptual.
Meeting abstract presented at VSS 2018