Perception of a stepping-across affordance

In this study, we investigated the information that is necessary to perceive the stepping-across affordance of a given obstacle. The first experiment involved 2 tasks where participants had to judge the step-acrossability of an obstacle and then physically step across an obstacle under 2 different visual conditions (binocular and monocular). The results of this Ist experiment suggest that monocular information was sufficient to perceive the stepping across affordance of an obstacle. In the 2nd experiment, however, we questioned the role of movement in the actor-environment system on the ability to perceive affordances. This experiment consisted of 3 different tasks. The Ist involved participants physically stepping across an obstacle, the 2nd involved participants judging the step-acrossability of an obstacle this time in a fixed stationary position, and the 3rd involved participants judging the step-acrossability of an obstacle when moving towards the given obstacle. In short, our results show that the participants' ability to perceive their own action boundaries is dependent on a strict coupling between perception and movement.