Investigating Spatial Awareness within an SSVEP-based BCI in Virtual Reality

Brain-Computer Interfaces (BCIs) allow users to communicate and to control their environment without the use of peripheral muscles. One of the commonly used BCI paradigms is called steady state visual evoked potentials (SSVEPs). It is controlled by brain signals induced through gazing at a constantly flickering light source. In this article, a VR-based SSVEP-controlled simulation is presented and evaluated, in comparison to the standard desktopbased version. Three control classes were used to control the application. The experimental task was to navigate (in first person view) through a virtual maze and reach the desired destination (the optimal path required at least 26 commands). Participants performed the task twice, using either a head mounted display (HMD), or the laptop screen, to compare the paths and investigate the spatial awareness with the HMD. During the first run, the participants needed to explore the maze (different corridors and doors on 3 levels) in order to reach the destination (a teleporter room). There were three commands available for the user: "Turn left", "Forward", and "Turn right". All participants were able to complete both versions (HMD and laptop screen). On average, the number of commands needed to complete the task in the online experiment was 51 and 62 for the HMD and laptop screen, respectively. The average time of the task for the HMD scenario was 287.16 seconds and for the laptop 435.79 seconds, almost 51.75% higher. We found, that the participants achieved a better spatial awareness with the HMD setup.