Voice Stress Analysis (VSA) is a controversial technology that records psychophysiological stress responses in a human voice. A person suffers psychological stress when under pressure, i.e when being asked a question that instills fear of exposure.
The consequences of lying and being exposed triggers a 'high stress' voice signature which the voice stress analyzer then records. Many intelligence agencies as well as private forensic psychophysiologists worldwide utilise voice stress analysis in preference to polygraph technology.
In this article on Voice Stress analysis Phillip Nakata outlines the basics of what Voice Stress Anlaysis is all about.
Voice Stress Analysis
-Is the other person who you think is your loyal friend or companion really honest with you?
-Is the other person really who you think they are?
-What if you have a way to sense 'deceit' so no one could lie to you anymore??
Voice stress analysis (VSA) is a very real, viable and applicable technology for truth verification
...for everyday use. Why? - Because it is effective in separating the less stressful act of being truthful,
from all the other 'grey' responses. It filters 'all the good guys' out from the 'rest' - for example, those
innocent of insurance fraud or a crime. Furthermore:
-VSA technology has always been accessible to anyone on the Internet; It's just technically 'messy' going
from an audio recording to viewing/hearing the selective results.
-VSA is a reliable "truth verifier" vs. perfect 'lie-detector" per se, as such responses' are sometimes caused
by other emotions such as confusion, unwillingness, etc.
-VSA can help act as a 'sixth' sense ... weeding out most responses as being truthful and sincere (the
silence)... relieving any doubt of their honesty and integrity - GOOD NEWS
-VSA alerts are cause for concern in any case. While it may not always indicate a deceitful lie, it indicates
some stressful condition causing the reaction - deceit or confusion, attention, anger, excitement,
unwillingness, etc. - all possibly important to know or find out further - CONCERN, it could well be a lie.
All muscles in the body, including the vocal chords, vibrate in the 8 to 12 Hz range....This is known
to be caused by the production and release of a chemical, as explained in the Scientific American
Article "Psychological Tremor" Vol. 224, No. 3, 1971.
-Some people have higher stress and some have low, and averages change from day to day along
with mood. What all people have in common is that their stress levels are constantly changing
within their current range - changes which indicate the "perceived jeopardy" or "danger" of
statements being made. A lie is often dangerous, humiliating, or injurious to get caught at, so lies
tend to stand out on stress measurements
-In moments of stress, like when you tell a lie that you dare not get caught at, the body prepares for
fight or flight by increasing the readiness of its muscles to spring into action. Their vibration
increases from the relaxed 8 to 9 Hz, to the stressful 11 to 12 Hz range.
-It's not the 'lie' itself, but the fear, unease or other emotional stress about a 'deceitful lie', that
causes the visual or audio alerts in voice stress and voice emotional analysis.
-A person with no compunction could tell extensive casual lies to these programs with no response - as is
evident in testing with 'mock' scenarios. But when the same person talks of significant matters, these
programs detects the stress.
VSA consumer applications include public freeware like TruthVSA3 (Windows), Prevaricator (Windows),
LiarLiar (Linux) and ShakyVoice (PPC). Or, you can also purchase software like Ex-Sense (windows),
Fortress (Windows - 'abandonware'), LieSpy (Nokia only), KishKish (Skype), or X13-VSA (Windows) – all
available on the Internet.
You do it all yourself or use a service, but the most critical issue for good feedback is a good audio
recording of your subjects' responses. There are some simple, but very important guidelines to follow:
-Relaxed, Non-threatening Atmosphere: (less controlled environments)
-No 'Mock' Testing: Never attempt to apply testing in 'mock' (made-up) scenarios (i.e. never ask how the
subject feels in an 'imagined' situation)
-Take a "positive" approach: Apply the overall approach with the PRIMARY intention of confirming that
your subject is not deceitful when making a statement or responding to a question; Candid recording is
best; Next best is cleverly staging in questions and answers
-Matters of 'significance': Ask questions or initiate conversation on matters of "significance" that elicit
emotional responses (for example, their opinion on a controversial subject); Record 5-15 brief, to the point
statements; If possible, ask at least one question that might be a lie
-ALWAYS be aware of the law in your own state: Laws vary state to state. In most states, including
California, you can record and analyze people as long as they give consent. Elsewhere, it's legal to run an
analysis if only one party to the conversation - you, rather than your subject - consents to the taping
It starts with just making an audio recording. VOIP users only need software for that – others need call /
sound recording software and a phone pick-up (or a tape recorder). Then "process" your recording and
analyze it for truth(s) or anomalies (stress or lies); Consider using 2-3 free VSA programs for comparison.
