The effect of height in the picture plane on the forward displacement of ascending and descending targets.

The effect of height in the picture plane on the remembered location of ascending or descending targets was examined. Consistent with previous research, memory was displaced forward in the direction of motion. The magnitude of forward displacement was larger for targets low in the picture plane than for targets high in the picture plane, and this was observed with ascending motion and with descending motion. This pattern is consistent with the hypothesis that memory for the location of ascending or descending targets is biased by the effects of implied gravitational attraction on the velocity of those targets, and some implications of such a bias for issues in mental representation are noted.