Using virtual reality to study the impact of audience size on cortisol responses to the Trier Social Stress Test

Virtual Reality Trier Social Stress Test (VR-TSST) protocols have been shown to effectively elicit psychophysiological stress by having participants perform a speech and math task while viewing a virtual (non-present) audience. However, few studies have utilized VR technology to examine variables that would otherwise be difficult to manipulate in the lab. This study examined the impact of a large VR audience (i.e., 200 members) on the physiological (i.e., cortisol) and psychological responses of 140 individuals. Participants were randomly assigned to one of three conditions: an in-person (2-person) audience, VR 2-person audience, or a VR 200-person audience condition. Salivary cortisol was collected to assess physiological reactivity and recovery. Participants self-reported psychological responses to the TSST including stress, arousal, emotions, and perceptions of the audience. Results revealed that all conditions elicited stress reactivity. The VR 200-person condition resulted in greater cortisol concentrations and more negative affect than the small VR 2-person audience. Thus the effectiveness of a VR-TSST may be enhanced by the use of a larger virtual audience stimulus.