Bodala Indu P, Li Junhua, Thakor Nitish V, Al-Nashash Hasan
Singapore Institute for Neurotechnology (SINAPSE), National University of SingaporeSingapore, Singapore; NUS Graduate School of Integrative Sciences and Engineering, National University of SingaporeSingapore, Singapore.
Singapore Institute for Neurotechnology (SINAPSE), National University of Singapore Singapore, Singapore.
Front Hum Neurosci. 2016 Jun 7;10:273. doi: 10.3389/fnhum.2016.00273. eCollection 2016.
Maintaining vigilance is possibly the first requirement for surveillance tasks where personnel are faced with monotonous yet intensive monitoring tasks. Decrement in vigilance in such situations could result in dangerous consequences such as accidents, loss of life and system failure. In this paper, we investigate the possibility to enhance vigilance or sustained attention using "challenge integration," a strategy that integrates a primary task with challenging stimuli. A primary surveillance task (identifying an intruder in a simulated factory environment) and a challenge stimulus (periods of rain obscuring the surveillance scene) were employed to test the changes in vigilance levels. The effect of integrating challenging events (resulting from artificially simulated rain) into the task were compared to the initial monotonous phase. EEG and eye tracking data is collected and analyzed for n = 12 subjects. Frontal midline theta power and frontal theta to parietal alpha power ratio which are used as measures of engagement and attention allocation show an increase due to challenge integration (p < 0.05 in each case). Relative delta band power of EEG also shows statistically significant suppression on the frontoparietal and occipital cortices due to challenge integration (p < 0.05). Saccade amplitude, saccade velocity and blink rate obtained from eye tracking data exhibit statistically significant changes during the challenge phase of the experiment (p < 0.05 in each case). From the correlation analysis between the statistically significant measures of eye tracking and EEG, we infer that saccade amplitude and saccade velocity decrease with vigilance decrement along with frontal midline theta and frontal theta to parietal alpha ratio. Conversely, blink rate and relative delta power increase with vigilance decrement. However, these measures exhibit a reverse trend when challenge stimulus appears in the task suggesting vigilance enhancement. Moreover, the mean reaction time is lower for the challenge integrated phase (RTmean = 3.65 ± 1.4s) compared to initial monotonous phase without challenge (RTmean = 4.6 ± 2.7s). Our work shows that vigilance level, as assessed by response of these vital signs, is enhanced by challenge integration.
保持警惕可能是监视任务的首要要求，在这些任务中，人员面临着单调但高强度的监测任务。在这种情况下警惕性下降可能会导致危险后果，如事故、生命损失和系统故障。在本文中，我们研究了使用“挑战整合”来提高警惕性或持续注意力的可能性，这是一种将主要任务与具有挑战性的刺激相结合的策略。采用一项主要监视任务（在模拟工厂环境中识别入侵者）和一个挑战刺激（降雨时段遮挡监视场景）来测试警惕性水平的变化。将具有挑战性的事件（由人工模拟降雨导致）整合到任务中的效果与初始单调阶段进行了比较。收集并分析了n = 12名受试者的脑电图（EEG）和眼动追踪数据。作为参与度和注意力分配指标的额中线θ波功率以及额部θ波与顶叶α波功率比，由于挑战整合而增加（每种情况p < 0.05）。脑电图的相对δ频段功率在额顶叶和枕叶皮质也因挑战整合而显示出具有统计学意义的抑制（p < 0.05）。从眼动追踪数据获得的扫视幅度、扫视速度和眨眼率在实验的挑战阶段呈现出具有统计学意义的变化（每种情况p < 0.05）。通过对眼动追踪和脑电图具有统计学意义的指标之间的相关性分析，我们推断扫视幅度和扫视速度会随着警惕性下降以及额中线θ波和额部θ波与顶叶α波的比率而降低。相反，眨眼率和相对δ功率会随着警惕性下降而增加。然而，当任务中出现挑战刺激时，这些指标呈现出相反的趋势，表明警惕性提高。此外，与没有挑战的初始单调阶段（平均反应时间 = 4.6 ± 2.7秒）相比，挑战整合阶段的平均反应时间更低（平均反应时间 = 3.65 ± 1.4秒）。我们的研究表明，通过这些生命体征的反应评估的警惕性水平会因挑战整合而提高。
