Study on physiological indexes during mental focus task comparison between near-infrared spectroscopy, electroencephalography, heart rate variability and peripheral arterial tonometry

Abstract

In this research, we focused on near-infrared spectroscopy (NIRS) as an alternative technique for mental state analysis, and compared its performance with other conventional techniques such as electroencephalography (EEG), heart rate variability (HRV), and peripheral arterial tonometry (PAT) during stress and healing task. In our experiment, we measured biological signals during stress or healing simultaneously with those techniques for comparison. Our NIRS results showed that the amount of total hemoglobin (totalHb) in the frontal cortex was increased during stress task, and that it decreased during healing task. Conventional physiological analysis techniques such as EEG and HRV, however, showed inconsistent results during tasks. Only PAT gave the consistent results in many of subjects. Our results suggested that NIRS and PAT might have correlation to mental stress, and can be useful to analyze stress condition.