Modeling Reduced User Experience Caused by Visual Latency

Two experiments were conducted to investigate the influence of delayed visual feedback on users’ motor performance and subject experience. In a Fitt’s-law target acquisition task, participants moved a cursor from a home location to a spherical target with delayed visual feedback. The experimental trials were blocked by latency (Experiment 1) to allow participants to get adapted to a constant delay or tested in random order (Experiment 2). Both experiments found significant impact of delay on motor performance, and the larger the Index of Difficulty of movement, the greater the performance detriment. A modified Fitts’-law model described the results very well with an additional multiplicative component of latency. Participants’ ratings of subjective experience with different latencies could be well-predicted from their motor performance. Between-experiments comparisons further revealed the effects of sensorimotor adaptation to constant delays. The results provide guidance to the design of VR/AR/tele-operative applications.