Effects of Illumination Level and Sense of Direction on Land Navigation Performance

This research quantitatively assessed the ability of infantrymen to perform a navigation task in conditions of limited visibility without the aid of night vision devices. Simulation of night was also tested by having the soldiers wear light-attenuating devices, and individual differences between good and poor navigators were studied with regard to the soldier's personal history, attitudes, and performance on cognitive tests aimed at discriminating sense of direction. The experiment required 30 soldiers to perform a dead-reckoning task to four checkpoints over a 2,330 m course in mountainous desert. Ten soldiers navigated during the day, 10 navigated at night, and the remaining 10 navigated in the day but wore light-attenuating devices to simulate night. half the soldiers in each group had a poor sense of direction, according to their own self-ratings, and the other half a good sense of direction.