Polygraph Glossary Practice

hidden key

Definition

The hidden key is the critical item in a Known-Solution Peak of Tension test. It is \"hidden\" because innocent examinees do not know which item is critical — it is embedded in a list of apparently similar questions. There is one key per test, and the examiner knows its identity before testing begins.

What Is a Hidden Key?

A hidden key is a protocol element in certain stimulation test formats where the examiner observes or knows the examinee's selected item but does not disclose this knowledge immediately. The examiner collects the stimulation test data, identifies the response to the known item, and may use the hidden key to verify sensor function and examinee responsiveness before deciding whether and how to demonstrate the result to the examinee.

Purpose

The hidden key approach gives the examiner flexibility to evaluate the quality of the stimulation test data before committing to a demonstration. If the physiological data clearly identifies the correct item, the examiner can proceed with a confident demonstration that reinforces the examinee's psychological set. If the data is ambiguous, the examiner may choose not to disclose the result or may use the information for calibration purposes without demonstration.

Contrast with Other Stim Formats

The hidden key contrasts with the blind format (where the examiner genuinely does not know the answer), the false key (where an incorrect item is announced), and the open demonstration (where the examiner reveals the correct identification immediately). Each format has different psychological effects on the examinee and serves different purposes within the examination protocol.

Related Terms

See: key, false key, stimulation test.

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Cross-references

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