Cognitive representation of motion: evidence for friction and gravity analogues.

Five experiments examined whether judgments of the locations of horizontally moving targets were influenced by implied friction between the targets and larger stationary surfaces. When targets crashed through a barrier, forward displacement decreased. When targets slid along the upper or lower edge of a single surface, forward displacement decreased. When targets slid along the upper or lower edge of a single surface, forward displacement decreased; when targets slid between the upper and lower edges of different surfaces, forward displacement decreased further. Targets not in contact with a surface exhibited larger forward displacement with greater target velocities, but contact with a surface attenuated or reversed this pattern. When targets slid along the upper edge of a surface, downward displacement increased; when targets slid along the lower edge of a surface, downward displacement reversed. Downward displacements were larger for larger targets, especially after contact with a surface. The data suggest that target representations contain analogues to friction and gravity that influence remembered position.