What Is Skin Conductance?
Skin conductance (SC) is a broad term for two exosomatic electrodermal phenomena: skin conductance level (tonic/baseline) and skin conductance response (phasic/stimulus-evoked). Modern polygraphs typically measure SC rather than Skin Resistance.
Historical and Modern Context
The evolution of polygraph instrumentation — from early mechanical devices to modern digital systems — reflects the broader advancement of the field from subjective interpretation to validated, structured Test Data Analysis">test data analysis. Modern instruments from manufacturers such as Lafayette, Limestone, and Stoelting incorporate multiple measurement channels, digital recording, and computerised scoring capabilities.
Professional Context
This concept forms part of the knowledge base expected of qualified forensic psychophysiologists. Training at APA-accredited schools covers the theoretical foundations, practical applications, and research evidence underlying all aspects of polygraph methodology. Ongoing continuing education ensures practitioners stay current with developments in the field.
For comprehensive information on polygraph terminology and methodology, explore the complete polygraph glossary or visit the Polygraph Examiner Hub.