精神运动警觉性任务在不同知觉负荷下的疲劳状态监测

精神疲劳是由于长时间的认知活动引起的一种疲劳形式,不同任务水平可能造成不同的疲劳状态。本研究采用双任务范式,利用精神运动警觉性任务(Psychomotor Vigilance Task,PVT)的不同指标,考察了不同任务水平下的视觉搜索任务引起的不同精神疲劳状态。结果发现:PVT任务的最快10%反应时指标与自评疲劳程度结果一致,随着任务持续时间的增加而增加,最快10%反应时能够反映不同任务水平条件下的疲劳状态变化。注意忽视频次指标能够反映简单任务条件下的疲劳状态变化。平均反应时指标的时间主效应和任务主效应都显著,可能是反映精神疲劳状态和任务负荷情况的综合指标。PVT任务的最慢10%反应时指标,仅仅存在显著的任务效应,可能主要体现了任务负荷状态的变化。这些结果表明,PVT任务各指标能够反映不同任务水平引起的疲劳状态的不同变化,是研究和监测不同状态下精神疲劳程度较好的任务选择。

Psychomotor Vigilance Monitors Different Fatigue States

Mental fatigue is a form of fatigue that results from prolonged cognitive activity,and different levels of tasks caused different states of fatigue.In line with our predictions,the search efficiency was significantly higher when the perceptual load was low,and subjective fatigue rating significantly increased after participants finished performing the dual task.Critically,objective PVT performance parameters displayed significant variation across perceptual load.In accordance with scores on the subjective fatigue,the PVT fastest RTs were higher at the end of the session than in the beginning,and no significant perceptual load main effect,suggesting that the fastest was the general indicator for detecting the fatigue effects.Specially,The PVT lapse frequency can tell fatigue states apart,that is,lapsing increased nearly significantly in the low perceptual load,while there were no differences in the low perceptual load.The grand mean showed significantly perceptual load and time-on-task main effect.The PVT slowest 10% was only significant perceptual load main effect,suggesting that it's an indicator to task parameter.These findings indicated that the different PVT outcomes indicators can distinguish the differentiate fatigue states.