Rimarčík, TimotejKandera, Branislav2025-10-152025978-80-554-2158-2https://drepo.uniza.sk/handle/hdluniza/1282Fatigue is a critical factor in aviation safety, contributing significantly to human error. This study aimed to validate a methodology for measuring performance decline due to fatigue, using both objective and subjective approaches. Eight university students participated in a two-day measurement involving psychomotor vigilance tests (PVT) for reaction time and self-assessment on the Karolinska Sleepiness Scale. Sleep duration was reduced to induce acute sleep disruption. Results demonstrated a measurable decline in cognitive performance, particularly on the second day following reduced sleep. A moderate positive correlation was found between subjective and objective measurements, confirming the validity of the dual-measurement approach. The study highlights the negative impact of sleep deprivation on performance and supports the methodology’s potential use in human performance education within aviation.otherFatigueSleepPsychomotor vigilance taskKarolinska sleepiness scaleWorking Paperhttps://doi.org/10.26552/pas.Z.2025.1.53