A high-speed BCI based on code modulation VEP

TLDR

Electroencephalogram-based brain–computer interfaces are noninvasive but their low communication speed limits practical use. This study introduces a high‑speed BCI that employs code‑modulated visual evoked potentials. The system uses 32 time‑shifted binary pseudorandom sequences as target stimuli and applies multichannel canonical correlation analysis for identification. In online tests, it achieved an average information transfer rate of 108 ± 12 bits min⁻¹, with a maximum of 123 bits min⁻¹.

Abstract

Recently, electroencephalogram-based brain–computer interfaces (BCIs) have attracted much attention in the fields of neural engineering and rehabilitation due to their noninvasiveness. However, the low communication speed of current BCI systems greatly limits their practical application. In this paper, we present a high-speed BCI based on code modulation of visual evoked potentials (c-VEP). Thirty-two target stimuli were modulated by a time-shifted binary pseudorandom sequence. A multichannel identification method based on canonical correlation analysis (CCA) was used for target identification. The online system achieved an average information transfer rate (ITR) of 108 ± 12 bits min−1 on five subjects with a maximum ITR of 123 bits min−1 for a single subject.