Evaluating a multi-player brain-computer interface game: challenge versus co-experience

Brain–computer interfaces (BCIs) have started to be considered as game controllers. The low level of control they provide prevents them from providing perfect control but allows the design of challenging games which can be enjoyed by players. Evaluation of enjoyment, or user experience (UX), is rather a new practice with BCI applications. The UX of multi-player BCI games, or co-experience, is especially scarcely assessed. In the study we report in this paper, we relied on observation analysis of social interaction to infer co-experience of pairs of players while they were playing a collaborative multi-player game using BCI. To investigate the effect of perceived level of control on co-experience, we compared BCI control to a more reliable mouse control. In order to investigate the co-experience related factors beyond the level of control, we compared BCI control to an equally reliable control mechanism. Our results show that low level of control dampened collaborative interaction while enhancing emotional interaction within pairs of players. Thus, the challenge of playing a computer game using BCI can influence the co-experience.