The internal cue seems to be to continue walking until they are tired. Toddlers sit down on the floor wherever they are and a few people functioning within ACL 2.4 will drop to the floor too. Most people will sit on a nearby chair. There are people who do not seem to experience feeling tired and they need regular assistance to sit down and rest.
While walking, the objects that capture their attention are barriers that they walk around, stop in front of or confine them. Walls, doors, gates, tables, couches, chairs are all big objects that influence their navigation. Small objects, below their knees will probably not be noticed. Common problems include steps, curbs, raised thresholds and uneven ground. Walking is limited to flat surfaces.
Their awareness of external space seems to be limited to where they are standing or sitting now and those objects that are above their knees.
Their walk is really a shuffle. They may be shuffling along because they do not perceive the relationship between their feet and the floor.