Polygraph Glossary Physiology

pupillary response

Definition

Pupillary response is the change in pupil diameter in response to stimuli. Dilation results from sympathetic activation or parasympathetic suppression. Several researchers have investigated pupil dilation as a stress/deception index, and it continues to be of interest in PDD research.

What Is Pupillary Response?

Pupillary response is the change in pupil diameter in response to stimuli. Dilation results from sympathetic activation or parasympathetic suppression. Several researchers have investigated pupil dilation as a stress/deception index, and it continues to be of interest in PDD research.

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

EDAElectrodermal Activity Measurement of electrical conductance changes in the skin caused by sweat gland activity, recorded via finger plates ... Valsalva's maneuver The Valsalva manoeuvre involves forced exhalation against a closed glottis, increasing internal pressure. This produc... allostasis Allostasis is a concept describing how the brain and body maintain stability through change. Unlike the older concept... all-or-none law The all-or-none law states that a neuron will respond to its greatest ability or not at all. Stimuli that do not meet... breathing Breathing (also called respiration) is one of the standard physiological signals recorded in PDD testing. Respiratory... skin potential Skin potential (SP) is an endosomatic electrodermal measure — voltage generated internally by the dermis without exte...

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