Enhancing Perceived Situation Awareness and Reducing Perceived Workload with a Likelihood Alarm Display

The researchers investigated the effects of a likelihood alarm display (LAD) on perceptions of workload and situation awareness (SA) during varying degrees of taskload. Twenty-four psychology students reacted to alarms while performing a complex primary task. The researchers examined participants performances during four experimental sessions. Two conditions of alarm display (binary and likelihood) and task load (low and high) were manipulated within groups. In addition, alarm display order (binary first or likelihood first) and task load order (low first or high first) were examined between groups. Results showed greater SA and reduced workload when participants used a likelihood alarm display and when they experienced low task load. Significant order effects also occurred. This study demonstrated the positive effects of a likelihood alarm display on perceptions of workload and SA, and suggests that LAD use may reduce workload and enhance SA.