Effects of familiarity of music on vigilant performance.

35 subjects, randomly assigned to five groups in a 2 x 2 + 1 between-subjects design, performed a vigilance task under familiar rock, familiar easy-listening, unfamiliar rock, unfamiliar easy-listening, and no music conditions. Familiar music significantly increased heart rate and percent detections and also mitigated the classical vigilance decrement. Type of music had no significant effect. It was concluded that the psychological chaaracteristics of noise are at least as important as its physical characteristics in determining level of vigilance performance.