For field use
Visual Guide · Dossier

How the Polygraph Works

It does not read lies; it reads the body under cognitive stress.

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Why it matters
Measures involuntary physiological responses
Cognitive stress drives the signals
Compares baseline against relevant states
No single response proves deception

Respiration

  • Track changes in rate and depth
  • Watch for rhythm disruption
  • Record signals through pneumo belts

Electrodermal Activity

  • Measure sweat gland activity
  • Link spikes to sympathetic arousal
  • Read signals via finger sensors

Cardiovascular

  • Track heart rate fluctuations
  • Monitor blood pressure changes
  • Capture readings through cuff or sensor

Movement

  • Detect fidgeting and micro-movements
  • Flag muscular tension as countermeasure
  • Record motion through dedicated sensors

The Question Set

  • Open with a pre-test baseline interview
  • Mix neutral baseline questions
  • Compare relevant against control questions

Reading The Charts

  • Score traces with algorithms and judgment
  • Watch EDA spikes and respiration inhibition
  • Weigh pattern and comparison, not single reactions

What Triggers Reactions

  • Expect fear of consequences
  • Account for cognitive load
  • Recognize emotional conflict and memory

Operator Considerations

  • Control your baseline deliberately
  • Minimize unnecessary stress
  • Maintain physiological steadiness throughout
01

Baseline

Establish normal responses with neutral questions

02

Probe

Ask relevant case questions

03

Compare

Contrast reactions across question types

04

Score

Judge pattern, not perfection

Consistency and plausibility beat perfection every time.

Dossier