The Effects of Mental Workload: Soldier Shooting and Secondary Cognitive Task Performance

Abstract : The dismounted soldier of the future will be 'loaded' with more information processing tasks while he performs shooting tasks. It is conceivable that in the future, some increased level of cognitive tasking may be performed simultaneously with shooting tasks. The effect of shooting under cognitive load has not been studied to date. It is imperative that the soldier not be overburdened mentally because that would result in decreased soldier survivability and lethality. This study was performed at the U.S. Army Research Laboratory's small arms shooting performance research facility. The present study proposed the examination of the ability of the soldier or Marine to perform various cognitive tasks while shooting. Additionally, the study examined the ability of soldiers or Marines to maintain the primary task of shooting pop-up friend-or-foe scenarios while performing secondary tasks of mathematical problem solving and situational awareness (SA) memory recall tasks. Finally, the study examined the effect of cognitive workload levels on the ability of soldiers to correctly make 'shoot-don't shoot' decisions in a friend-or-foe target environment. Participants were 16 U.S. Marines whose ages ranged from 18 to 25 years old. The shooting task consisted of a 24-target pop-up scenario that used friendly (white circular marking on the chest of the target) and enemy (olive drab green) E-type silhouette targets. Half of the targets were friendly and half were enemy. Ranges consisted of 50, 100, 150, 200, 250, and 300 meters. Target exposure time was 4 seconds. Soldiers were in a foxhole-supported standing position for all trials. M16A2 rifles with iron sights were used. Two types of secondary tasks, which were provided aurally, were given to subjects to attend to while they performed shooting scenarios: mathematical problem solving (addition problems) and an SA memory recall task. Each type of task consisted of three levels of difficulty.