Can potentials of unbalanced complex kinetics of heart rate variability estimate drowsiness?

Several investigations have shown that most traffic accidents are due to drowsy driving. Much research has been carried out to address this issue. The authors of one study were able to measure the drivers' heart rate variability and estimate their drowsiness. In this study, we investigated the relationship between the drowsiness and physiological condition of the drive in the driving simulator environment by quantifying autonomic nervous system activity using “potentials of unbalanced complex kinetics” (PUCK) analysis of heart rate variability and conventional frequency-domain analysis using the Karolinska sleepiness scale (KSS). Both frequency-domain and PUCK parameter values had significant statistical differences for almost all subjects in relation to drowsiness: no drowsiness (mean KSS scores <; 5.5), light drowsiness (KSS scores > 5.5 and <; 7.5), and heavy drowsiness (>7.5). Furthermore, the classification ability of PUCK analysis was superior to that of frequency-domain analysis. Therefore, PUCK analysis of heart rate variability may be useful for assessing drowsiness while driving.