Do Velocity Vectors Support Multiple Object Tracking?

Abstract

We examined the effect of velocity vectors on human ability to extrapolate movement of multiple moving objects. This was achieved using an identity tracking task, in which objects (line-drawings of familiar objects) first move for 5 s, after which they temporarily disappear from view. In order to examine different aspects of vector information, we compared 4 velocity vector conditions: (1) no vectors were displayed; (2) only a history trail was displayed; (3) a condition where the end of the velocity vector pointed to exactly where the objects would reappear after the masking; (4) a constant heading length was displayed. Based on recent studies on Keane and Pylyshyn (2006) and Oinonen et al. (2009), we hypothesized that the condition, where exact location information is presented, would improve performance compared to baseline. The results supported this hypothesis by indicating that history trail or directional vector do not improve performance but only complete visual information about the future location will help to anticipate movement in multiple object tracking.