Abstract: Inattentional deafness refers to that individual ignores the unexpected auditory stimuli while concentrating on their tasks. This phenomenon is common among our daily life and it is a major threat to aviation and traffic safety. In aeronautics, auditory alarms can provide emergency information for pilots and air-traffic controllers. The analysis of air safety reports indicated that many aviation accidents are due to the lack of response to unexpected and critical auditory alarm. Why does inattentional deafness happen? Human factor engineering reported three reasons to explain this phenomenon. First, pilots mistrust the alerting system due to higher false rate, which akin to cry-wolf effect. Second, the aggressive, distracting, and annoying nature of auditory alarms increased the level of stress of pilots. They didn’t think about the meaning of alarms but close the noise. Finally, for pilots, the ability to perceive auditory alarm become poorer due to frequent noise exposures and aging issues. Nevertheless, these explanations are often reported in aviation accidents analysis and are not sufficient to fully explain why does a pilot ignore the unexpected and critical auditory alarm. Cognitive psychology showed that the perceptual load, cognitive load and working memory played an important role in inattentional deafness. In the cockpit, pilots must simultaneously monitor many instruments, perceive, process, memorize and retrieve an important amount of information, which causes higher perceptual load and cognitive load. Perceptual load theory indicated that higher perceptual load tasks consume most of attentional resources, leaving little or none remaining for processing unexpected information. Cognitive control theory showed that working memory have a key role in attention control. Some studies found that the effect of working memory load on inattentional deafness is the opposite of perceptual load and tasks involving high working memory load consume working memory resources, leaving litter or none remaining for suppress distractions or unexpected stimuli. Hence, auditory alarms can be perceived under higher working memory load. However, other studies showed that working memory protects distraction by exerting top-down control. Pilots cannot perceive the unexpected auditory alarms under higher working memory load. Neurophysiological studies found that the amplitudes of N100 was reduced under higher working memory load and these studies indicated that the unexpected alarm was filtered at an early processing stage. While some studies showed that the amplitudes of P300 was reduced under higher working memory load and the unexpected alarm can be processed in late processing stage. In the current study, we reviewed the papers and found that perceptual load, cognitive load, working memory, task related and visual dominant take accounts to this phenomenon. Perceptual load studies found that the exhaustion of resources under higher perceptual load caused unexpected auditory stimuli to be filtered at an early processing stage. From the aspect of cognitive control, the unexpected auditory stimuli can be processed in late processing stage. The top-down cognitive control took a dominant role in auditory stimuli misperception. Future studies can extend its paradigm and theoretical framework to other safety fields. Moreover, further studies can explore how to avoid inattentional deafness through cognitive training.

Key words: inattentional deafness, auditory alarm, perceptual load, cognitive load, working memory

摘要： 无意失聪是指当人们集中精神做事时，会忽略非预期的听觉刺激。这种现象在现实生活中普遍存在，它对航空和交通安全构成巨大威胁。研究者们发现高知觉和高认知负荷条件下因认知资源有限导致无意失聪。且随着负荷增加，被忽略的听觉刺激诱发的早期（N100）和晚期（P300）神经活动有所减弱。这表明非预期听觉刺激可以进入晚期加工阶段，但其能否被感知可能取决于与工作记忆相关的额顶网络的抑制控制程度。而工作记忆容量及其负荷与无意失聪关系的现有研究结果之间还存在不一致性。未来研究可以将其范式和理论拓展到其他安全生产领域，并运用认知训练等方式规避无意失聪，从而减少人因失误。

关键词: 无意失聪, 听觉警报, 知觉负荷, 认知负荷, 工作记忆