Cognitive impact of social virtual reality: audience and mere-presence effect of virtual companions

Sharing experiences with others is an important part of everyday life. Immersive virtual reality (IVR) promises to simulate these experiences. However, whether IVR elicits a similar level of social presence as measured in the real world is unclear. It is also uncertain whether AI-driven virtual humans (agents) can elicit a similar level of meaningful social co-presence as people-driven virtual-humans (avatars). The current study demonstrates that both virtual human types can elicit a cognitive impact on a social partner. The current experiment tested participants’ cognitive performance changes in the presence of virtual social partners by measuring the social facilitation effect (SFE). The SFE-related performance change can occur through either vigilance-based mechanisms related to other people’s co-presence (known as the mere presence effect: MPE) or reputation management mechanisms related to other people's monitoring (the audience effect: AE). In this study, we hypothesised AE and MPE as distinct mechanisms of eliciting SFE. Firstly, we predicted that, if head-mounted IVR can simulate sufficient co-presence, any social companion’s visual presence would elicit SFE through MPE. The results demonstrated that companion presence decreased participants' performance irrespective of whether AI or human-driven. Secondly, we predicted that monitoring by a human-driven, but not an AI-driven, companion would elicit SFE through AE. The results demonstrated that monitoring by a human-driven companion affected participant performance more than AI-driven, worsening performance marginally in accuracy and significantly in reaction times. We discuss how the current results explain the findings in prior SFE in virtual-world literature, and map out future considerations for social-IVR testing, such as participants virtual self-presence, and affordances of physical and IVR testing environment