Human Sensibility Evaluation Using Photoplethysmogram (PPG)

This study presents a method for human sensibility evaluation using photoplethysmogram (PPG) signal instead of electrocardiogram (ECG) or electroence-phalogram (EEG) signals. For this objective, PPG signals for two emotional states (positive/negative) are collected. To evoke the test emotions, happy (or joyful) and sad (or irritating) movie files are collected and played in subjects' monitor. From the acquired PPG signal, the heart rate variability(HRV) is calculated. Using the HRV and its FFT spectra, the human sensibility is evaluated. Since the heart is a representative organ which is controlled by the autonomic nervous system (ANS), the ANS may reflect the changes in emotion. Additionally a biofeedback technique to respond the bad(negative) mood is designed. The biofeedback software is developed with motion image player interacting with the results of the sensibility evaluation. It was shown that HRV was changed according to the subject's emotions. Accordingly, the sensibility evaluation test showed feasibility of our method.