Investigating the role of auditory and visual sensory inputs for inducing relaxation during virtual reality stimulation

Abstract

Stress is a part of everyday life which can be counteracted by evoking the relaxation response via nature scenes presented using immersive virtual reality (VR). The aim of this study was to determine which sensory aspect of immersive VR intervention is responsible for the greatest relaxation response. We compared four conditions: auditory and visual combined (audiovisual), auditory only, visual only, and no artificial sensory input. Physiological changes in heart rate, respiration rate, and blood pressure were recorded, while participants reported their preferred condition and awareness of people, noise, and light in the real-world. Over the duration of the stimulation, participants had the lowest heart rate during the audiovisual and visual only conditions. They had the steadiest decrease in respiration rate and the lowest blood pressure during the audiovisual condition, compared to the other conditions, indicating the greatest relaxation. Moreover, ratings of awareness indicated that participants reported being less aware of their surroundings (i.e., people, noise, light, real environment) during the audiovisual condition versus the other conditions (p < 0.001), with a preference for audiovisual inputs. Overall, the use of audiovisual VR stimulation is more effective at inducing a relaxation response compared to no artificial sensory inputs, or the independent inputs.

Figure 1

Still photo from three of the videos provided to the participants via the head-mounted display.

Figure 2

Physiological changes in heart rate (top), respiration rate (middle), and mean arterial pressure (bottom) over the 30-min intervention period. (Left) Raw data (n = 42) which has been centered to zero. 95% confidence intervals (CI) are shown at the bottom of each plot. (Right) Modelled data generated using the Generalized Additive Mixed Model and the raw data. 95% confidence intervals (CI) are shown at the bottom of each plot.

Figure 3

Participant (n = 42) responses to subjective questionnaires. (a) Shows the percent of participants who preferred the different conditions. (b) Subjective rating of how aware the participants were of people in the room during the different conditions. (c) Subjective rating of how aware the participants were of the noises in the room during the different conditions. (d) Subjective rating of how aware the participants were of the light in the room during the different conditions. Vertical bars represent the standard error and horizontal bars represent significant differences between the conditions, the alpha level was set to 0.05.