Quantifying the effects of reduced update rate on motor performance and user experience

Abstract

We report two experiments that investigated the impact of reduced visual updating speed on users’ motor performance in a Fitts’-law task. The update rate of visual feedback was set between 10 and 30 Hz. In Experiment 1, the trials were blocked by update rate, allowing participants to get adapted to the reduced visual feedback. In Experiment 2, all trials of different update rates were intermixed and presented in random order. Both experiments found that movement time increased with decreasing update rate. Regression analyses revealed that the Fitts’-law model could be extended to accommodate the findings by including a multiplicative component of frame interval (reciprocal of update rate). The participants’ subjective experience reduced rapidly when the update rate was lower than 20 Hz, and the rating data could be modelled using movement time. The results were discussed in the context of implications for developing VR/AR applications.