Design of SSVEP Enhancement-Based Brain Computer Interface

Brain computer interface (BCI) system is a communication bridge between the brain and the external device, and it has been rapidly developed in the recent years. Here, steady state visually evoked potential (SSVEP) is one of the most frequently used control methods for BCI due to its advantages of low training requirement and high stability. However, some people present unobvious SSVEP feature at the location of the primary visual cortex, and this will reduce the performance of SSVEP-based BCIs. In this study, a novel field programmable gate array (FPGA)-based brain computer interface with SSVEP enhancement is proposed to improve the above issue. In the proposed system, a SSVEP-enhancement active dry electrode is designed to acquire good quality of electroencephalography (EEG) without conductive gels, and further enhance the local EEG signal. The experimental results show the proposed system can effectively improve the signal-to-noise ratio of SSVEP and the information transfer rate. Moreover, compared with the current SSVEP-based BCIs in the previous studies, the proposed BCI system contains the advantages of local EEG enhancement, wearablility, wireless transmission, front-end BCI translation, and it contains the potential of applying in many BCI applications in daily life.