“…Among these existing EEG-based BCIs, SSVEP-BCI has been extensively investigated due to its high communication speed and less calibration time [15], [16], [17], [18], [19], [20], [21]. Currently, SSVEP-BCI has been applied in multiple fields, including robot control [12], [18], [22], [23], cognitive evaluation [24], [25], and text speller [15], [17], [20], etc. SSVEPs are periodic brain responses elicited by repeated visual stimuli, manifested by increased brain activities at stimulus frequencies and their harmonics [26].…”