A study of autonomic nerve indexes related to subjective discomfort during a virtual reality experience

Abstract

Measuring discomfort during a virtual reality (VR) experience (VR sickness) is important to prevent health hazards and to encourage people to utilize VR technology safely. Using simultaneous measurements of subjective discomfort intensity and electrocardiogram (ECG), we investigated changes in the autonomic nervous activity related to the discomfort caused during a VR experience. In this study, the ECGs of sixteen healthy adults were monitored while they watched a 5-minute VR roller coaster video, which included various rotational and reciprocating motions, using a head-mounted display. The participants were instructed to continuously report their momentary intensity of discomfort using a slider device. Their heart rate variability was analyzed using the R-R interval data of ECGs to calculate the heart rate, the sympathetic nervous activity, and the parasympathetic nervous activity. The values obtained during the time periods of moderate to severe discomfort were compared with those during control periods, in which the roller coaster was at the station and motionless. The results indicate that participants' perceived discomfort was associated with increases in heart rate and sympathetic nervous activity, and a decrease in parasympathetic nervous activity. These results suggest that there is a significant association between autonomic activity and subjective discomfort during VR experiences. This kind of cardiac autonomic nervous activity could be used as a useful biological index for the objective evaluation of VR sickness.