The influence of signal hue and background music pitch on vigilance

Humans generally display vigilance decrement during sustained cognitive workloads, while visual and auditory stimuli have been shown to elicit arousal, which influences the level of user vigilance. This study explored the effects of hue and background music pitch on user vigilance. Thirty-five participants performed a 10-min Psychomotor Vigilance Test with background music playing. Three hue conditions (red, green, and yellow) and two background music pitch conditions (high and low pitch) were randomly combined in each task, and the reaction time (RT) and number of lapses under different conditions were measured. We found that the overall vigilance performance was the best (shortest RT and fewest lapses) and the worst, and the vigilance decrement was the fastest and the slowest, respectively, with the red and the yellow signal. Moreover, the overall vigilance performance was best with low-pitched background music, while the pitch did not affect vigilance decrement. These findings can be used in situations with repeated color-signal stimulation and music playing (e.g., driving, signal monitoring, and physical training) to improve users' vigilance performance.