Steady state noise and music and vigilance.

Abstract 12 subjects were tested twice on a one-hour visual vigilance task. 6 subjects first performed the teat accompanied by continuous white noise presented at 72 dB (A). The second time they performed the test it was accompanied by music, presented at a level previously calibrated to give an. average integrated output, over one hour, of 72 dB A. A further 6 subjects performed the two tests in the reverse order. Performance was analysed into hits and false alarms at 3 levels of confidence for report. Although raw score performance did not differ between conditions, a signal detection theory analysis showed that diseriminability was higher in white noise than music. The setting of the cautious criterion showed an interaction between noise conditions and time on task.