A Novel SSVEP Modulation Method Utilizing VR-Based Binocular Vision

This paper presents a novel method for modulating steady-state visual evoked potentials (SSVEP) based on binocular vision in virtual reality (VR). The method involves displaying monocular frequencies in the left and right view of VR to encode nine binocular targets using only two frequencies. We constructed a VR-BCI system and validated the effectiveness of this binocular-encoded paradigm through the task-related component analysis (TRCA) algorithm, which is a supervised approach based on individual templates. The results showed a recognition accuracy of 79.05% and an information transfer rate (ITR) of 43.38 bits/min with a data length of 2 seconds. The electroencephalography (EEG) responses of the binocular combinations exhibited unique characteristics compared to traditional SSVEP, suggesting potential for further optimization in terms of performance. This proposed method reduces the frequency requirements for encoding SSVEP-speller and highlights the potential of VR-BCI in utilizing binocular characteristics, which could contribute to the practicality and high-speed implementation of SSVEP-based brain-computer interface (BCI) systems.