Improving the performance of NIRS-based brain-computer interfaces in the presence of background auditory distractions

In this paper, the effects of auditory distractions on the performance of brain-computer interfaces (BCI) based on near-infrared spectroscopy (NIRS) are investigated. Experiments show that NIRS-BCI specificity decreases by an average 19% when operated in the presence of continuous background noise (relative to operation in silence) and by 13% when operated in the presence of startle noises. To improve BCI performance in noisy environments, a simple yet effective startle noise compensation strategy is proposed. Acoustic environmental conditions are tracked in realtime and false BCI activations that occur within seconds of detected startle noises are suppressed. Experiments show NIRS-BCI systems equipped with the proposed compensation system attaining performances in noisy conditions comparable to those attained in silent conditions.