Polygraph Glossary Physiology

tonic response

Definition

A tonic response is a slow shift in baseline level in response to changing conditions (e.g., temperature, posture). Some examiners consider tonic trends diagnostic in Peak of Tension tests, though research evidence is limited.

What Is a Tonic Response?

A tonic response is a slow shift in baseline level in response to changing conditions (e.g., temperature, posture). Some examiners consider tonic trends diagnostic in Peak of Tension tests, though research evidence is limited.

Significance in PDD

This concept is part of the theoretical and practical framework supporting psychophysiological detection of deception. Understanding it helps practitioners, researchers, and informed consumers appreciate the scientific foundations of modern polygraph testing and the ongoing refinement of techniques and methods based on empirical research.

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.

Cross-references

More physiology terms in this glossary

Sympathetic Response Activation of the sympathetic branch of the autonomic nervous system, producing the physiological changes measured by... eupnea Eupnea is normal, quiet breathing at rest. In polygraph testing, eupnea represents the baseline respiratory pattern a... EMGElectromyography A technique for measuring electrical activity produced by skeletal muscles. While not a standard polygraph channel, E... Habituation The progressive decrease in physiological response magnitude when a stimulus is repeated without consequence. In poly... Stimulus-Response Theory The theoretical framework underlying polygraph testing which holds that specific stimuli (test questions) produce mea... GSRGalvanic Skin Response An older term for electrodermal activity (EDA). Refers to changes in the electrical resistance of the skin caused by ...

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