Effects of Temporal Stressors on Vigilance and Information Processing

Abstract

The data of two control and ten experimental studies of the effects of continuous work and sleep loss on sustained multiple-task performance, representing more than 9 man-years of synthetic work by 89 different subjects, were reanalyzed to permit comparisons of the performances of three watchkeeping tasks and two active tasks that are time-shared in a multiple-task performance battery (MTPB). Specific comparisons were made of the two control groups, of the effects of 48 hours of continuous work and sleep loss with and without the employment of pulse rate and EEG-theta bio feedback and autoregulation, of the effects of the duration of continuous work and sleep loss (36, 44, or 48 hours), of the effects of the duration of rest and recovery following 36 hours of continuous work (12, 6, 4, 3, and 2 hours), and of circadian rhythm and 36-hour continuous work interactions. Eight specific conclusions are reached, the most general of which is that the relevance of typical laboratory research with single-task watchkeeping tests, including the capability of its findings being generalized to, and implemented in, practical situations involving monitoring performances within operational manmachine systems is seriously questioned, if not compromised, by the findings.