Perceptibility and utility of sticky targets

Researchers have suggested that dynamically increasing controlto-display (CD) gain can assist in targeting, by increasing the effective width of targets in motor space, which makes targets feel sticky. Although this method has been shown to be effective, there are several unexplored issues that could affect its use in real-world interfaces. One of these is perceptibility: in particular, the difference between the perceptibility and the utility of the technique. If CD gain changes are highly noticeable even at levels that are not helpful, the technique could be seen as overly intrusive. If CD gain changes are more useful than noticeable, however, the technique could be applied more widely. To explore this issue, we carried out a study that tested both the utility and the perceptibility of CD gain in single-target selection tasks. We found that although even small amounts of gain reduction significantly improved targeting times, participants did not consistently notice the effect until the gain difference was much higher. Our results provide new understanding of how changes in CD gain are experienced by users, and provide initial evidence to suggest that sticky targets can benefit users without a high perceptual cost.