Gaze when walking to grasp an object in the presence of obstacles.

People generally look at positions that are important for their current actions, such as objects they intend to grasp. What if there are obstacles on their path to such objects? We asked participants to walk into a room and pour the contents of a cup placed on a table into another cup elsewhere on the table. There were two small obstacles on the floor between the door and the table. There was a third obstacle on the table near the target cup. Participants often looked at the items on the table from the beginning, but, as they approached and entered the room, they often looked at the floor near the obstacles, although there was nothing particularly informative to see there. Thus they primarily relied on peripheral vision and memory of where they had seen obstacles to avoid knocking over the obstacles. As they approached the table, they mainly looked at the object that they intended to grasp and the obstacle near it. We conclude that people mainly look at positions at which they plan to physically interact with the environment, rather than at items that constrain such interactions.