“…Despite the importance of micro-sleep during driving, the development of micro-sleep detection has been delayed because of too many variations in associated experiments, such as whether the study involves a simulation or real driving (Gao et al, 2019;Ko et al, 2021b), use of different physiological signals (Gao et al, 2019;Karuppusamy and Kang, 2020), and the criteria used to define micro-sleep (Gao et al, 2019;Ko et al, 2021b). On the one hand, micro-sleep is similar to NREM stage 1 during night sleep because NREM stage 1 is the transition period between wakefulness and sleep (Balaji et al, 2021). In microsleep, EEG theta activity is dominant like NREM stage 1 (Wu et al, 2013;Skorucak et al, 2020a).…”