  Emerging technologies in the domain of extended reality offer rich, new
possibilities for the study and practice of joint music performance. Apart from
the technological challenges, bringing music players together in extended
reality raises important questions on their performance and embodied
coordination. In this study, we designed an extended reality platform to assess
a remote, bidirectional polyrhythmic interaction between two players, mediated
in real time by their three-dimensional embodied avatars and a shared, virtual
drum circle. We leveraged a multi-layered analysis framework to assess their
performance quality, embodied co-regulation and first-person interaction
experience, using statistical techniques for time-series analysis and
mixed-effect regression and focusing on contrasts of visual coupling (not
seeing / seeing as avatars / seeing as real) and auditory context (metronome /
music). Results reveal that an auditory context with music improved the
performance output as measured by a prediction error, increased movement energy
and levels of experienced agency. Visual coupling impacted experiential
qualities and induced prosocial effects with increased levels of partner
realism resulting in increased levels of shared agency and self-other merging.
Embodied co-regulation between players was impacted by auditory context and
visual coupling, suggesting prediction-based compensatory mechanisms to deal
with the novelty, difficulty, and expressivity in the musical interaction. This
study contributes to the understanding of music performance in extended reality
by using a methodological approach to demonstrate how co-regulation between
players is impacted by visual coupling and auditory context and provides a
basis and future directions for further action-oriented research.
