An evaluation of an adaptive automation system using a cognitive vigilance task

The performance of an adaptive automation system was evaluated using a cognitive vigilance task. Participants responded to the presence of a green “K” in an array of two, five, or nine distractor stimuli during a 40-min vigil. The array with the target stimulus was presented once each minute. Participants EEG was recorded and an engagement index (EI=20×beta/(alpha+theta)) was derived. In the negative feedback condition, increases in the EI caused the number of stimuli in the array to decrease while decreases in the EI caused the number of stimuli to increase. For the positive feedback condition, increases in the index caused an increase in the array size (AS) while decreases caused a decrease in the array size. Each experimental participant had a yoked control partner who received the same pattern of changes in array irrespective of their engagement index. A vigilance decrement was seen only for the positive feedback, experimental group.