Visual access and attention in two-year-olds' event reasoning and object search

Several recent studies have revealed substantial limitations in 2-year-olds' ability to search accurately for objects that have undergone unseen movement, even along highly constrained paths. In many of these studies, children observed a ball as it rolled down a track and behind an occluding panel that contained 4 doors. The track had a barrier that was partly visible and could be placed in locations corresponding to the doors. When the ball came to a rest against the barrier and behind the occluder, the child's task was to find the ball by opening the correct door. The search accuracy of 2-year-olds has not differed from chance across several variations of this task. This research was conducted to identify the source of 2-year-olds' limitation in this domain. Children were granted a full view of the event before the ball was occluded with a door panel. Children's performance was better under this condition, but was still not systematically accurate unless their gaze remained locked onto the correct location. Two-year-olds' weak performance in these search tasks appears to be more a consequence of limitations in spatial integration than in their representation of unseen movement.