Influence of Task and Situational Variables on the Applicability of Vigilance Data to Physical Security

Vigilance is one of the most thoroughly researched areas of human performance. Volumes have been written concerning vigilance performance in both laboratory and real-world settings, and there is a clear trend in the literature toward an increasing emphasis on the study of operational task behavior under environmental conditions that are common to real world jobs. Although a great deal of this research has been designed to test various aspects of the many theories of vigilance, there is a general belief that vigilance research is relevant and applicable to the performances required in real-world monitoring and inspection tasks. Indeed, many of the reported studies are justified on the basis of their apparent relevance to vigilance requirements in modern man-machine systems, industrial inspection tasks, and military jobs. There is a growing body of literature, however, which suggests that many vigilance studies are of limited applicability to operational task performance. For example, Kibler (1965) has argued that technological changes have altered job performance requirements to the extent that laboratory vigilance studies are no longer applicable to real-world jobs. Many others have simply been unable to reproduce the typical “vigilance decrement” in field situations. This has led Teichner (1974) to conclude that “the decremental function itself is more presumed than established.”