Development of Flicker Visual Stimulus by Mixing Fundamental and Its Harmonie Frequencies for SSVEP-based Brain-Computer Interface

A practical brain-computer interface (BCI) system is challenging research to develop software and hardware. Steady-state visual evoked potential (SSVEP) is the most popular use for spelling and steering an electric wheelchair. SSVEP achieves high accuracy and less time for training. However, an SSVEP response was not clearly present for all users. Therefore, this work proposed an improvement to the SSVEP visual stimulation pattern. We demonstrated a modified visual stimulus pattern by mixing fundamental and harmonic flickering frequencies for enhancing SSVEP response. In the experiment, we observed that the proposed visual stimulus pattern could yield a high amplitude of SSVEP than the conventional visual stimulus pattern, around 9%. We will further add participants and implement for online BCI system.