## 1 Introduction  
In recent years, China has actively advanced the intelligent development of coal mines [1], significantly enhancing the mechanization of coal mining operations [2]. As frontline workers at excavation sites [3], coal mine tunneling machine operators are taskedwith extensive human-machine interaction, such as operating roadheaders, under hazardous conditions, including coal and gas outbursts, high temperatures, dust, noise, and high humidity [4]. Additionally, these operators must maintain a heightened level of vigilance to monitor abnormal conditions in the roof, floor, and coal walls, and the presence of surrounding personnel near the roadheader [5]. This requires operators to frequently perform or switch between multiple tasks simultaneously [6], with task interruptions being both common and often urgent [7]. Working in such harsh environments, roadheader operators are particularly susceptible to fatigue due to heavy workloads, shift work, and sleep deprivation, which disrupt their circadian rhythms [8]. Evidence from case studies highlights that task interruptions under fatigued conditions can lead to unsafe behaviors among workers. Research further indicates that 90% of accidents in human-machine interaction processes are attributable to unsafe human behaviors [9]. As a result, worker behavior plays a pivotal role in ensuring the safety and efficiency of coal mining operations [10].  
Previous studies have independently examined the associations between task interruptions, fatigue, and unsafe behaviors; however, few have considered the combined effects of both factors on unsafe behaviors in coal mining environments. This study aims to fill this gap by investigating the behavioral and neural mechanisms underlying task interruptions and fatigue states. Unsafe behaviors are assessed through behavioral performance, with a focus on analyzing the impact of task interruptions on operators' safety behaviors in a fatigued state. In existing research, [PERSON] et al. [11] explored the impact of task-unrelated interruptions on the neural representation of working memory, observing that task interruptions lead to shifts in attention and adjustments in information retrieval mechanisms. [PERSON] et al. [12] found that task interruptions trigger changes in multiple brain regions, with the frontal, temporal, and insular lobes showing the most pronounced associations with interruptions. These findings reveal how task interruptions, by affecting different brain regions, in turn influence operators' work efficiency and decision-making abilities. This study draws on the ACT-R (Adaptive Control of Thought-Rational) cognitive architecture [13], particularly its concepts of executive control and resource allocation. ACT-R is of significant relevance in studying unsafe behaviors in high-risk environments, as it suggests that task interruptions increase cognitive load, making it difficult for individuals to switch between tasks and slowing down information processing [14]. Furthermore, the theory posits that task interruptions affect attention mechanisms and executive control processes [15]. Building on the ACT-R framework, this study employs the spatial 2-back task as the primary interruption task, alongside simple mathematical problems as interruptive tasks. Additionally, while previous studies have primarily focused on the effects of secondary task interruptions on subsequent performance, less attention has been given to pauses in task flow. This study expands the scope by incorporating research on pause-based interruptions. Furthermore, by using the AX-CPT (Continuous Performance Test) task to induce fatigue in participants, this study explores the effects of task interruptions on brain activity under both fatigued and non-fatigued states, while also investigating the moderating role of fatigue in the task interruption process.