“Eyes-closed” SSVEP-based BCI for binary communication of individuals with impaired oculomotor function

In the present study, a new paradigm for steady-state visual evoked potential (SSVEP)-based brain-computer interface (BCI) was proposed, which can be used for disabled individuals with impaired oculomotor function. The proposed EEG-based BCI system allows users to express their binary intentions without a need to open their eyes. A pair of glasses with two LEDs flickering at different frequencies was used to present visual stimuli to participants with their eyes closed. Through offline experiments performed with 11 participants, we confirmed that human SSVEP could be modulated by visual selective attention to a specific light stimulus penetrating through the eyelids. After customizing the parameters of the proposed paradigm based on the offline analysis results, binary intentions of five participants were classified in real time. The average ITR of our online experiments reached 10.83 bits/min, demonstrating the feasibility of our BCI paradigm.