Measuring the Impact of Working Memory Load on the Safety Performance of Construction Workers

Cognitive processes have been found to play a significant role in contributing to the human errors that lead to construction accidents. A better understanding of cognitive processes as they relate to construction will elucidate the more predictable varieties of human fallibility and allow for the creation of strategies to avoid said errors. To date, no published study has empirically investigated the relationship between working memory and the human errors that lead to accidents in construction. To address this gap, this study uses eye-movement metrics to examine how working-memory load impacts worker’s attentional allocation and the detection of potential hazards in construction. To determine whether changes in memory load influence scan patterns and awareness of hazards, 19 students were recruited to participate in an eye-tracking experiment in which working memory load was manipulated. The results demonstrated that as working memory load increases, the ability of participants to identify hazards decreases. In addition, the results demonstrate that there is a significant difference between the visual search strategies of people under different working-memory loads. This study provides a proof of concept that eye movements can be used as an indicator of variation in working-memory load among construction workers while they search for a hazard without any active interference with the subject.