2.4. Daytime Sleepiness and Sustained Attention Measurements
PVT
Subjects completed the psychomotor vigilance task (PVT) every 6 h from 09:15 on D1 to 15:00 on D2. The KSS was filled in, and the EEG was recorded at 09:15 only on D1 and D2, corresponding to 2 and 26 h of prolonged wakefulness, respectively (We used a computer-based version of the 10 min PVT [The Karolinska sleepiness scale (KSS) is a subjective scale used to grade a subject’s sleepiness from 1 to 9, with 1 indicating “extremely alert” and 9 indicating “extremely sleepy” [