Target size and displacement along the axis of implied gravitational attraction : Effects of implied weight and evidence of representational gravity

Effects of target size on displacements between the actual and remembered vanishing points of moving and stationary targets were examined. For horizontally or vertically moving targets, target size influenced displacement only along the axis aligned with the direction of implied gravitational attraction; larger targets exhibited greater downward displacement when targets moved horizontally, greater forward displacement when targets descended, and smaller forward displacement when targets ascended. For stationary targets, target size did not influence displacement along the axis aligned with the direction of implied gravitational attraction. The data are consistent with the hypothesis that mental representation incorporates an analogue of weight. It is proposed that weight, rather than mass, influences displacement because the representational system incorporates subjective or experiential aspects of physical principles rather than physical principles per se. An observer who perceives a target that is moving in a consistent direction will usually remember that target as having traveled slightly further than it actually did; in other words, memory for the final orientation or location of a target will be slightly displaced in the direction of anticipated target motion (for a review, see Hubbard, 1995b).