为探究不同模态转换下任务切换对监控人员警觉度衰减现象的影响，采用脑电实验法，设计了危险动作识别、危险场景识别等任务，并结合行为数据及事件相关电位（Event Related Potential，ERP）技术进行综合分析；实验重点考察在任务切换过程中，不同模态的任务之间进行切换对监控人员警觉度的具体影响；通过对煤矿监控调度人员的实证研究，揭示了切换任务的模态差异性对监控员警觉度的影响及其内在机制。结果表明：当在相同刺激任务间进行切换时带来的工作绩效下降，主要原因在于任务切换产生的切换成本导致注意力分散，具体体现在任务切换后P300和P200平均波幅的升高；但是在不同刺激任务间进行切换时，尤其是切换到听觉刺激任务时，被试者的警觉度水平反而得到了一定程度的提升。

In order to investigate the effects of task switching under different modal transitions on the attenuation phenomenon of monitor alertness, event related potential (EEG) experimental method was used to design tasks such as hazardous action recognition, hazardous scene recognition for comprehensive analysis combined with behavioral data and ERP technology; through the empirical study of the coal mine monitoring and dispatching personnel, we reveal the effect of the modal difference of switching task on the alertness of the monitoring personnel and its internal mechanism. The experiment focuses on the specific effects of task switching between different modes on the alertness of supervisors. The results show that the main reason for the decrease of work performance when switching between the same stimulus tasks is the distraction caused by the switching cost, which is reflected in the increase of the average amplitude of P300 and P200 after task switching. However, when the task was switched between different stimuli, especially when the task was switched to auditory stimuli, the participants’ alertness level was improved to some extent.