The relationship between a location of visual stimulus and SSVEP

Brain Computer Interface (BCI) is useful as an interface to operate a computer and external equipment using brain activities. A Steady-State Visual Evoked Potential (SSVEP) is known as the powerful tool to achieve BCI systems. A user of BCI focuses on the visual stimulus which produces brain activities used as an input of BCI. On the other hand, the user needs to pay own attention to surrounding situation for avoiding accidents. This means that the user should turn own attention to both the environment and the visual stimulus. The practical SSVEP based BCI often places visual stimuli around a fixation point which displays the surrounding situation captured by a camera. In addition, the visual stimulus equipped with moving vehicles has a slight movement due to our body movement and vehicle movement. This fact shows that the visual stimulus is moving at the side of user´s vision. However, the relation of a SSVEP and a place and moving of visual stimulus has not been discussed. In this paper, we measure and analyze SSVEP for visual stimulus located on the surrounding area of fixation point, and a moving visual stimulus.