Abstract
Aim: When we observe an instructor's motions to learn a new motor skill, or when we try to intercept a moving object undergoing characteristic motion, we must rely on short-term visual memory (VSTM) to record motion path(s). Our apparent ability to remember motion raises several questions: 1) How much of an object's motion can we remember? 2) Does memory performance depend on how the motion path is spelled out? 3) Does memory for motion path compete with other forms of VSTM? Methods: In each trial, participants must remember the path of either an object undergoing straight-line motion with abrupt turns or a static display of its path. Results: We found that path memory declined when the object underwent more turns, despite the constant overall path length. Memory for a static path display was better than memory for a moving path display, even when we tested recall with both static and moving probes. For moving displays, apparent motion was as difficult to remember as smooth motion. This memory showed no clear primacy or recency effects. Finally, path VSTM did not compete with VSTM for the moving object's color or shape. Conclusion: Although VSTM for a moving path is constrained by path complexity, we have found no evidence that it reduces VSTM performance for other properties of the moving object. How VSTM for motion path relates to multiple-object-tracking, and whether this memory is enhanced by active motor tracing remain to be explored.
This study was supported by NSF 0345525, NIH MH071788, and the Harvard College Research Program.