NCJ Number
219812
Journal
Polygraph Volume: 36 Issue: 2 Dated: 2007 Pages: 70-83
Date Published
2007
Length
14 pages
Annotation
This paper reports on the cause of changes in the cardiovascular readings when measuring psychophysiological manifestations of deception that occur in response to emotion-evoking questions in a polygraph exam.
Abstract
The amplitude changes that accompanied a change in arterial blood pressure were shown to be related to the relationship between cuff pressure and blood pressure measured at the monitoring site. Changes in tracing baseline were shown to accompany a change in blood pressure monitored at the cuff site. The changes that occur in pulse amplitude size are dependent on a number of factors that include systolic and diastolic changes throughout the examination and the cuff pressure. Since cuff pressure remains relatively constant throughout the chart collection phase, the primary variable is a change in blood pressure at the monitoring site. The experiment demonstrates the changes observed in the cardiograph tracings when measured blood pressure is changed without sympathetic nervous system (SNS) arousal. By raising and lowering the subject's arm, researchers manipulated the blood pressure recorded at the cuff site without attempting to raise the subject's arterial pressure. This presumably did not alter the subject's arterial pressure, so there was no swelling of the underlying tissue. The experiments tend to support the earlier work of Geddes and Newberg. If the cuff pressure is set below maximum oscillation pressure, as is typically done in modern polygraphy, a rise in arterial pressure will result in a baseline rise and a decrease in pulse amplitude. Research participants were three healthy adult men ages 35, 42, and 44. None were taking any prescription medications. For the arm-cuff testing, a standard 12-cm blood-pressure cuff was wrapped around the upper arm of the men while they were seated in a plastic portable polygraph chair. The instrumentation and the details of the procedure are described. 11 figures and 12 references