The user as a whole: emotional factors influencing the experience with brain-computer interfaces

While motor imagery brain-computer interface (MI-BCI) rehabilitation yields lasting upper-limb motor recovery after stroke, how the User eXperience (UX) evolves, within individual sessions and across consecutive days, remains poorly understood. Here we investigated the variations of users’ answers to UX questionnaires when training with a MI-BCI. 12 healthy naive users performed 5 application sessions (5 runs, 20 trials each), where some questionnaires were administered before using the BCI, while others after the BCI task was completed. To understand the relationship between emotional factors and the ability to control a BCI, the questionnaires collect information related to emotional arousal, use of stimulants, motivation, engagement, agentivity, anxiety and level of comfort perceived. Another publicly available dataset was used to understand results replicability. This metadata information aims to be used as predictors of the control capability and to provide perspective on the performance evolution. The participants reported being intensely engaged in the task, considered the feedback clear and useful, and the game motivating and reliable. Preliminary results indicate that those who did not change the imagery strategy throughout the sessions had better performances than those who actually did so. Understanding of the UX impact of the BCI controlling capability can significantly change our understanding of protocol designing for proper user engagement.