Exposure and Occluded Duration Effects in a Ball-Catching Skill

Male Ss (N=48) from a university population attempted single-handed catches of lawn tennis balls delivered by a mechanical projection machine. The within-and between-S variables in a split-plot factorial design were the period for which the ball was illuminated (VP) and the subsequent period of occlusion (OP). Both variables and their interaction were significant sources of variation. Generally the effect of VP diminished as OP was extended. This was discussed in terms of (1) information processing time and (2) motion prediction. With respect to the first issue, the most important variable was not VP, but a composite term VP + OP. On the second issue, support was provided for an hypothesis to account for prediction error raised in a previous study.