EXPERIMENTS ON VIGILANCE:DURATION OF VIGIL AND THE DECREMENT FUNCTION FOURTH IN A SERIES

摘要

Results of previous experiments on vigilance were reanalyzed for data on human performance during short (half-hour) and long (two-hour) vigils. The analysis indicated that length of vigil did not affect either the initial or terminal level of performance. However, the decrement in performance which begins immediately after the start of a long vigil was delayed in the short vigil. This change in the shape of the decrement function was attributed to different expectations by the subjects about the duration of the vigil, and is consistent with an expectancy theory of vigilance. These results support recommendations that monitoring tasks should be kept short if optimal performance is required.