Perception of a stepping-across affordance

In this study, we investigated the information that is necessary to perceiv e 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 v isual conditions (binocular and monocular). The results of this Ist experim ent suggest that monocular information was sufficient to perceive the stepp ing across affordance of an obstacle. In the 2nd experiment, however, we qu estioned the role of movement in the actor-environment system on the abilit y to perceive affordances. This experiment consisted of 3 different tasks. The Ist involved participants physically stepping across an obstacle, the 2 nd involved participants judging the step-acrossability of an obstacle this time in a fixed stationary position, and the 3rd involved participants jud ging the step-acrossability of an obstacle when moving towards the given ob stacle. In short, our results show that the participants' ability to percei ve their own action boundaries is dependent on a strict coupling between pe rception and movement.