Biosignal measurement and interpretation: State of arts and beyond

Abstract

Among biological signal fluctuations obtained by wearable devices, heart rate variability (HRV) is the most widely studied and successful. HRV researches have focused on two basic propositions: (1) HRV reflects autonomic function, and (2) HRV predicts prognosis. While PubMed's more than 50,000 HRV research papers present vast supportive evidence for these propositions, they still raise questions about their limitations and necessary conditions. The focus of the discussion is on the biological necessity of the association between HRV and autonomic function, the presence of HRV not mediated by autonomic nerves, the problems of autonomic function evaluation by HRV, and the validity of pulse rate variability as a surrogate of HRV, and exploration of new information value of HRV beyond autonomic nervous function and prognostic index. Based on recent researches on these topics, I would like to discuss the future of biological signal measurement and interpretation researches.