Alternative Displays for Discrete Movement Control

Abstract

This research examined performance in a single-axis discrete positioning task using three different mappings for the visual display of the movement space. In a normal display condition, displayed distance was proportional to actual distance. In a split-screen condition, 66.5% of the initial distance to the target was mapped into 50% of the visual space and 33.5% of the distance (containing the target) was mapping into the remaining 50% of visual space. Finally, in a log screen condition there was a logarithmic mapping from actual to visual space. The split-screen and log screen conditions resulted in magnification of the space containing the target and compression of space distance from the target. Results for movement time (MT) showed a significant effect of target width. MTs were longer for smaller targets. Performance with normal and log screens was equivalent in terms of overall level and in terms of rate of increase in MT with reduction in target size. A smaller rate of increase, however, was found for the split-screen display. MTs for the smallest target were faster with the split-screen display. Evidence suggests that fewer corrective movements were required for the smaller targets when using the split screen