PSE® stands for Psychological Stress Evaluator®. Since 1969, all PSE® models ( PSE 7010, PSE 5128, PSE 4202, PSE 2000, PSE Dek, PSE 101, PSE 1) detect, measure, and graphically display the degree of presence or absence of inaudible body tremors known as micro-muscle tremors. These tremors are superimposed on the human voice (at all ages) and on all warm blooded animals, such as dogs and cats. The tremors disappear according to the amount of stress that is present at the moment of a verbal utterance. This is referred to as Voice Stress Analysis™

The frequency modulation of the voice carrier takes place in the voice fundamental. What we know as the formant frequencies are those induced resonances which occur in the throat, mouth and nasal regions. These induced frequencies are really the ones that we recognize as speech for the fundamental is all but lost because of its low energy level. When the fundamental is present, it induces or excites the other formant areas much one tuning fork brought near another will cause the second one to vibrate at its own frequency. Any modulation (slight frequency change) which occurs in the fundamental also causes changes in the formants in the same ratio. The telephone line nominally passes 300 to 2600 Hz. The PSE in use normally ignores the fundamental so there is no real difference in acceptance bandwidth. In actual fact, we could produce the charts we see from the fundamental or any single formant alone because they are all a direct root of the fundamental. When we say 8-14 Hz per second, we are really saying that the fundamental or any formant changes at the rate of 8 to 14 Hz not that a 8 to 14 Hz signal is audibly present. As an example, let us say that a particular formant frequency was 1000 Hz at a particular point in time. This signal varied from 900 Hz to 1100 Hz. The variation, however, occurs at 8-14 times per second. This is what we refer to as the frequency modulation i.e. a frequency change which occurs 8 times every second. To detect and chart this, then we treat the particular formant or group of formants as a carrier,  whose frequencies are shifting at a given FM rate. This is analogous to the carrier of an FM station and this carrier can be demodulated with straight forward slope detection principles used in radio communication today. The only difference is the carriers we are looking at are not in millions of cycles, but in thousands of cycles.

A great benefit of the PSE system is that a recording is always made of the entire interview and test. All recordings are required to be kept for ten years by the PSE examiner for review if needed or in court for appeals. The PSE 7010 uses a extremely high quality microphone for recording directly into the computer. At the beginning of the interview with a subject for any type of a PSE test, the examiner gets the consent of the subject to be recorded. If the subject refuses to be recorded, the examiner refuses to proceed with the interview and the test. The recording protects everyone’s rights. The recording protects the PSE examiner from false accusations by the subject. The subject may make up lies later to get sympathy from a judge or jury. This is especially so with a female being tested. The recording also preserves any confession and details the subject might say. The recording protects the subject from false promises or threats by the examiner. Polygraph machines and imitation “voice lie detectors” never use a recorder. The old paper and pencil type written confessions can be easily discredited by a defense attorney.

For a truth verification test of a specific incident, the PSE examiner asks the subject various questions about the incident to see if the subject may have previous knowledge or involvement. After the PSE examiner is finished with his questioning of the subject, the examiner writes a series of questions to be asked on the test. All questions are reviewed with the person before the test.

The recording also includes the subject’s responses to the test questions.  These verbal responses are transformed into various patterns. The patterns on the earlier PSE instruments were printed on chart paper. The patterns are now displayed on the computer screen. The patterns can be displayed in various sizes, can be stretched and specific areas can be magnified for a very in-depth analysis. The patterns can also be printed using any computer printer. Each question in a test will have its own pattern. The PSE examiner evaluates the stress in each pattern. The examiner compares the various patterns to each other to see which pattern has the most stress. If the relevant questions (for previous knowledge or involvement of a situation) have the most stress than the person is attempting deception. If a irrelevant question has the most stress, the subject is being truthful in a test. This process of evaluation is also used for employment screening or psychological evaluations using the PSE.

NO drugs, alcohol or manual manipulations (counter-measures) affect the results of the PSE system. NO painful attached wires are ever used that polygraph and computer polygraph must always have. The painful attached wires cause many problems for the polygraph examiner. Polygraphs also have “inconclusive” which means after a truth verification test, the polygraph examiner still does not know if the person is being truthful or deceptive. “Inconclusive” answers are a waste of time and money. Those problems have always been trouble for the polygraph examiner. Those polygraph problems also lower polygraph accuracy. PSE never had those polygraph problems.

PSE can be used in person (overtly or covertly), in any language, over the phone (over any distance), from the radio or TV, from any previously made audio tapes or video tapes. Entire phrases or sentences can be analyzed for truth or deception.

Thousands of various PSE models have been sold worldwide for 45 years. PSE’s are used by law enforcement, Fortune 500 Corporations, security companies, military, insurance companies, mining companies, private investigators, college security, psychologists, psychiatrists, lawyers, public defenders, prosecutors, prisons, probation and parole(especially for sex offenders), embassies, airport security, Homeland Security, and many others. Patents covering the PSE were granted in the U.S. and around the world. The PSE has been utilized in the news media in various cases in the news. Jack Anderson, a very famous investigative reporter, used the PSE for some of his stories to determine the truthfulness of various people.

There is only one real technology for Voice Stress Analysis™. That technology is called PSE®. Only the original Dektor invented it. Only the new Dektor sells it. Only the original Dektor invented the proven training, testing and chart evaluation techniques for Voice Stress Analysis™.

Go to Dektor® when accuracy is a must!