The effect of stress on prospective memory in robotic command and control

Remembering to carry out an intention at the appropriate time (prospective memory-PM) requires attentional resources that may be limited in stressful circumstances. PM failures in high-risk/high stress environments, such as military operations, can have fatal consequences, and yet, the effect of stress on PM has received little attention. Prior studies that have examined stress and PM used a basic laboratory paradigm that is less applicable to high-risk/high stress environments and have not examined activity-based PM (PM that is elicited by a sequence of events), nor the combined effect of stress and divided attention. The current study examined the effects of stress and divided attention on event-based PM (PM that is elicited by environmental cues to signal the appropriate time to perform an intended action) and activity-based PM using an applied paradigm with participants remotely piloting robotic reconnaissance missions. Stress and divided attention were manipulated between subjects, and prospective memory was manipulated within subjects. The stress induction was administered prior to the execution of the tasks, with an additional noise stressor continuously on top of the tasks. Divided attention was an auditory odd-digit task during the experimental tasks. Event-based PM accuracy was unaffected by stress or divided attention. However, there was an increase in activity-based PM accuracy in the high stress condition, while no effect of divided attention was found. These results are the first to demonstrate that stress affects activity-based PM, and suggest along with prior literature that stress does not affect event-based PM.