NCJ Number
74434
Date Published
1980
Length
5 pages
Annotation
Results are reported from research that used a polygraph for psychophysiological assessment of dangerousness.
Abstract
A six-channel Grass polygraph was used to measure heart and skin resistance activity of subjects as they viewed a series of slides of violent scenes and neutral or nonviolent scenes. The volunteer subjects were divided into three groups of 30 according to the following categories: (1) inmates with a history of violent activity, (2) inmates with no recorded history of violent behavior, and (3) institutional employees (normal controls). Analysis of the data showed that heart rate activity was not significantly different among the groups. These results are insignificant since heart rate alone is a relatively ineffective response in field polygraphy. However, data on skin resistance activity, which is a sensitive response in field polygraphy, showed that during the first 10 seconds after slide presentation, frequency of skin resistance response increased by about 24 percent for both the normal and the nonviolent groups when responses to violent slides were compared to the neutral slides. For the violent subjects, the increases averaged about 65 percent. Caution is advised because results obtained by averaging subjects' responses can be misleading if used in interpreting individual responses. These results, along with similar results obtained from other research mentioned, suggest the polygraph or other psychophysiological assessment instruments can be used with more traditional assessment methods to provide information about dangerousness. Issues for further research in this area are mentioned. Four references are provided.