Finnish Institute of Occupational Health, Helsinki, Finland.
Nokia Bell Labs, Espoo, Finland.
J Sleep Res. 2019 Apr;28(2):e12755. doi: 10.1111/jsr.12755. Epub 2018 Aug 21.
Prolonged time awake increases the need to sleep. Sleep pressure increases sleepiness, impairs human alertness and performance and increases the probability of human errors and accidents. Human performance and alertness during waking hours are influenced by homeostatic sleep drive and the circadian rhythm. Cognitive functions, especially attentional ones, are vulnerable to circadian rhythm and increasing sleep drive. A reliable, objective and practical metrics for estimating sleepiness could therefore be valuable. Our aim is to study whether saccades measured with electro-oculography (EOG) outside the laboratory could be used to estimate the overall time awake without sleep of a person. The number of executed saccades was measured in 11 participants during an 8-min saccade task. The saccades were recorded outside the laboratory (Naval Academy, Bergen) using EOG every sixth hour until 54 hr of time awake. Measurements were carried out on two occasions separated by 10 weeks. Five participants participated in both measurement weeks. The number of saccades decreased during sustained wakefulness. The data correlated with the three-process model of alertness; performance differed between participants but was stable within individual participants. A mathematically monotonous relation between performance in the saccade task and time awake was seen after removing the circadian rhythm component from measured eye movement data. The results imply that saccades measured with EOG can be used as a time-awake metric outside the laboratory.
清醒时间延长会增加睡眠需求。睡眠压力会增加困意，损害人的警觉性和表现，并增加人为错误和事故的可能性。在清醒状态下，人的表现和警觉性受到生理节律和睡眠内稳态驱动力的影响。认知功能，特别是注意力，容易受到生理节律和睡眠驱动力的影响。因此，能够估计困倦程度的可靠、客观和实用的指标可能是有价值的。我们的目的是研究在实验室之外使用眼动电图（EOG）测量的眼球运动是否可以用来估计一个人没有睡眠的总清醒时间。在 8 分钟的眼球运动任务中，11 名参与者的眼球运动次数被测量。使用 EOG 在实验室外（卑尔根海军学院）每六小时记录一次眼球运动，直到清醒时间达到 54 小时。测量在两次相隔 10 周的时间进行。5 名参与者参加了两次测量周。在持续清醒期间，眼球运动次数减少。数据与警觉的三过程模型相关；参与者之间的表现不同，但在个体参与者中是稳定的。在从测量的眼动数据中去除生理节律成分后，在眼球运动任务中的表现和清醒时间之间存在单调的数学关系。研究结果表明，在实验室外，使用 EOG 测量的眼球运动可以作为清醒时间的指标。
