Applied Psychophysiology I: Detection of Deception, Vigilance, Job Design, and Workload
Over the years, psychophysiologists have developed, or stimulated the development of, increasingly sensitive and sophisticated instruments to measure the physiological variables in their psychological studies. The refined instruments and techniques have led to a precision that allows the measurement of physiological responses in many practical applications. The next two chapters address the question: How might the measurement of physiological responses help in the solution of practical problems? In order to find answers, we examine a number of research studies in a variety of areas. The main difference between the studies described here and those in earlier chapters is that applied research is generally performed to provide an answer to a specific problem, the solution of which has practical value. This is not to say that basic research is valueless, because it often leads to applications of information or techniques that eventually prove to be very useful. Thus, applied and basic research often support and complement each other.
The applications that we consider in this chapter are concerned with detection of deception, vigilance, and personnel considerations including ergonomics, workload, job satisfaction, job strain, human-computer interactions, and personnel selection. In the next chapter, we examine applications to sensory system testing, mental retardation, nervous system disorders, and behavior disorders.
Historical Background. The use of physiological measures to determine when an individual is lying is a controversial area with a long history. The controversy exists over the accuracy of the techniques and their use in personnel selection and in granting security clearances, as well as in criminal investigations. Woodworth and Schlosberg ( 1954) observed that the principle of SNS discharge (arousal) and its effects on inhibiting salivary secretion was used by the ancient Chinese in lie detection. The unfortunate suspect was given rice powder to chew on and then forced to spit it out. If the powder was still dry, the suspect was guilty! It was assumed that the guilty person would be fearful because of lies told during the interrogation process, and that this fright interfered with salivation. Obviously, a guilty person would not be able to moisten the dry rice! Furedy ( 1986) wrote that the earliest written account of psychophysiological observation in the detection of deception came from a Hindu medical source dating about 900 B.C. In this account, persons who lied about using poison on others showed such physiological changes as blushing, and behaviors such as rubbing their