Virtual Co-Embodiment: Evaluation of the Sense of Agency while Sharing the Control of a Virtual Body among Two Individuals

TL;DR

This paper introduces virtual co-embodiment, allowing shared control of a virtual avatar between users and autonomous agents, and investigates how control levels affect users' sense of agency and motor actions.

Contribution

It presents a novel concept of shared virtual embodiment and provides experimental insights into control perception and agency in collaborative virtual environments.

Findings

Participants overestimate their sense of agency when they anticipate avatar motion.

Participants perform similar motions regardless of actual control level.

Personality traits influence perceived control levels.

Abstract

In this paper, we introduce a concept called ''virtual co-embodiment'', which enables a user to share their virtual avatar with another entity (e.g., another user, robot, or autonomous agent). We describe a proof-of-concept in which two users can be immersed from a first-person perspective in a virtual environment and can have complementary levels of control (total, partial, or none) over a shared avatar. In addition, we conducted an experiment to investigate the influence of users' level of control over the shared avatar and prior knowledge of their actions on the users' sense of agency and motor actions. The results showed that participants are good at estimating their real level of control but significantly overestimate their sense of agency when they can anticipate the motion of the avatar. Moreover, participants performed similar body motions regardless of their real control over the avatar. The results also revealed that the internal dimension of the locus of control, which is a personality trait, is negatively correlated with the user's perceived level of control. The combined results unfold a new range of applications in the fields of virtual-reality-based training and collaborative teleoperation, where users would be able to share their virtual body.