Modern computer systems for instrumental lie detection.

sovremennie kompyuternie sistemi instrumentalnoidetekcii

V.A. Varlamov, G.V. Varlamov
Moscow

Modern computer systems for instrumental «lie detection».

When conducting polygraph tests, each specialist tries to create conditions that increase the effectiveness of the examinations.

If the subject is lethargic, sits in a half-sleep, sometimes yawns, then to obtain a reliable reaction it is necessary to bring him out of this state.

For these purposes, certain stimulation techniques are used.

Specialists know that after their implementation, the information content of indicators characterizing the level of emotional tension (stress) when asking significant questions increases significantly.

On the other hand, very strong emotional tension also does not contribute to increasing the reliability of the test results.

Therefore, in the pre-test interview, if the subject is very excited, the specialist tries to calm him down a little.

Extremes in the state of the subject (calm, overexcitation) equally do not contribute to the effectiveness of the tests.

There is a certain golden mean, i.e. a zone of the level of tension of the subject, in which polygraph tests are most effective.

The reason for this phenomenon lies in the peculiarities of the regulation of psychophysiological reactions of our body, formed in the process of human development

The change in a person's condition goes through two phases.

In an inactive, half-asleep state, a person's functional level is quite low (Fig. 1; segment A — B).

If the subject is tested at this time, then the changes in psychophysiological reactions to a significant question may be negligible, and it is not always possible to record them with a polygraph.

Let's imagine that during the examination, due to a significant question, emotional stress increased from a conditional 0 to 0.5 or even to 1.

In this case, the functional level remains practically constant, and, consequently, there will be no change in the psychophysiological reactions that ensure it.

If the subject is tested at this time, then the changes in the psychophysiological reactions to a significant question may be negligible, and it is not always possible to record them with a polygraph.

Let's imagine that during the examination, due to a significant question, emotional stress increased from a conditional 0 to 0.5 or even to 1.

In this case, the functional level remains practically constant, and, therefore, there will be no change in the psychophysiological reactions that ensure it.

sovremennie kompyuternie sistemi instrumentalnoidetekcii
Fig. 1 Changes in the functional state of a person
depending on the amount of emotional stress

In practice, a condition is possible when the introduction of additional emotional stress will have virtually no effect on the physiological indicators recorded by the polygraph (drowsy state and state of intense tension).

FU — functional level; EN — emotional stress;
A, B, C, D, E, F, G, H — points of the curve characterizing the functional level of the human body;
A-B — the person is in a half-asleep state or has taken a large dose of tranquilizers;
B-C — state of wakefulness;
B-G — optimal conditions for testing; D-E — plateau;
E-G — beginning of the decline in the functional level;
Z — the point of zero functional level, i.e. the practical death of a person.

The same dependence is preserved if the initial level of emotional stress is 14 conventional units, and a significant question caused an increase in emotional stress to 15, i.e. by 18.5% (segment E-G). In case of overstrain, there may be a reverse process — a decrease in indicators. If, when neutral questions were presented, the functional level corresponded to the curve at point E, then additional emotional stress caused by the presentation of a significant question may lead to its decrease (segment E — G), and, consequently, to a decrease in the value of the recorded physiological indicators. A further increase in emotional stress may lead to a zero functional level, i.e. the death of a person (point G).

The biological system that ensures the life of the organism is not linear. At the first stage of the response, with the growth of emotional stress, the level of its organization increases. Reaching its limit, it passes into the second phase, that is, there is a decrease in the functional capabilities of the organism, up to its death. An example of the possibility of the functional level curve falling to zero was described by A. Mosso (1887) in his work «Fear».

The most favorable functional state of the subject for testing is shown on the curve section, segment B — G. In this range, any increase or decrease in emotional stress will lead to a corresponding change in physiological indicators, and, most importantly, with extreme accuracy.

These features of regulatory mechanisms must be taken into account when conducting polygraph tests.

During prolonged testing, especially when the subject is exhausted by previous events, a fairly rapid transition of the functional state from one phase to another is possible. This is often the reason for a decrease in the body's response to a significant question compared to a neutral one.

The two-phase nature of responses to a significant question (increase or decrease) is a well-studied phenomenon that is characteristic of almost all systems of the human body. These primarily include linearity and nonlinearity in the regulation of physiological reactions.

This provision is directly related to counteracting testing using medications or narcotics, as well as using behavioral methods of distorting polygrams. In the first case, the subject affects his nervous system and complicates the testing procedure by taking the appropriate corrective drugs. In the second case, he uses various methods of influencing the polygraph examiner directly, hoping that somewhere, something will work.

For the express assessment of the patient's condition, an intelligent block was developed for the first time in the world, implemented in scale No. 1, assessing the emotional stress of a person in real time (Fig. 2).

It reflects the level of emotional arousal of a person. If the arousal is not at an optimal level, before testing it is necessary to either calm him down if he is very excited, or, conversely, stimulate him if he is inhibited, using certain techniques for this.

This is due to the fact that with its weak tension, as well as with overstrain, the responses to the presented stimuli can be significantly weakened. Sometimes a reverse reaction can be observed, and the response to a stimulus that causes great emotional tension will be the smallest.

When the functional system of the subject is in one of the extreme states, the difference in indicators between the reactions to neutral and significant questions is significantly reduced. Consequently, the reliability of the conclusion about the involvement or non-involvement of the subject in the crime under investigation is reduced.

If the extreme states of a functional system are unacceptable for testing, then how can we find the average, optimal state, in which physiological reactions are adequate and reflect the social significance of the presented stimuli with maximum reliability? In applied physiology, this phenomenon is observed when the regulation of physiological reactions is on the so-called linear section. In this state, the human body optimally restructures its functions commensurate with the changing internal or external environment. If, as a result of a stimulus, the load on the human body has increased by 5%, then the respiratory volume, hemodynamic indicators, etc. increase by the same amount.

In the practice of polygraph tests, the procedure for assessing the functional state was absent, despite its obvious need. The introduction of this scale allows for real-time assessment and, if necessary, promptly making the appropriate correction of the test subject.

sovremennie kompyuternie sistemi instrumentalnoidetekcii
Fig. 2 Scale for assessing the emotional stress of the subject

The STRESS scale is divided into three sectors.
Sector «LOW» — the functional state of the subject is reduced. He is not ready for a polygraph test. This condition may be caused by overfatigue or be the result of taking sedatives.
Sector «NORM» — the level of tension of the subject corresponds to the requirements for his functional state during polygraph tests. Regulation of physiological indicators is on the linear section, and an adequate response to the presented «stimuli» can be expected.
Sector «HIGH» — increased excitation of the subject leads to an inadequate response to the stimulus, for example, to the absence of a positive response to a significant question or its distortion (the response to a significant question may be lower than to a neutral one).
For the first time in the world, an intellectual block has been introduced that characterizes the ability of the subject to self-control of the testing procedure (Fig. 3).

SELF-CONTROL Scale
The scale characterizes the level of assessment of the testing procedure by the subject and the danger it poses to him.
If the pre-test interview is conducted correctly and the subject believes in the infallibility of the methodology and the competence of the specialist, then two states are possible:

sovremennie kompyuternie sistemi instrumentalnoidetekcii 2
Figure 3. Scale for assessing the level of control of the testing procedure by the subject

  1. a state of relative calm, if the subject has not committed any illegal actions. The information presented in the stimuli is more of an element of curiosity for him.
  2. a state of tension that manifests itself if the person being tested is involved in the crime being investigated. The presented stimuli are not indifferent to him. In each question, he expects a trick from the polygraph specialist and mobilizes all his functional capabilities.

The SELF-CONTROL scale is intended to assess these states.
Sector «LOW» — the subject is in a state of confusion. He evaluates events unstable. During this period, it is easiest to obtain a confession from him.

Sector «NORM» — the subject controls the surrounding events, which, in his opinion, do not pose a great danger to him.

Sector «HIGH» — the subject is maximally angry, expects questions that he would not like to answer. He evaluates the testing procedure as a real danger.

The third intellectual block of evaluation of the functional capabilities of the subject — the scale «INTERNAL AGGRESSION» (Fig. 4).
This scale evaluates the efforts that the subject makes to ensure control over events, which is practically an evaluation of the volitional efforts that accompany concentration. Of course, if the subject is involved in the crime being investigated, then the efforts made to maintain the level of concentration must be maximum. This is not always possible. Sleepless nights, pre-illness conditions or previous illnesses can greatly weaken the biological systems that ensure the maintenance of a high level of concentration.

This scale also allows you to assess the ability of the subject to resist the testing procedure, record its decline, as well as the effectiveness of the impact on the subject both in the pre-test period and during the polygraph test.

sovremennie kompyuternie sistemi instrumentalnoidetekcii 2
Fig. 4 Scale for assessing the energy supply of the testing procedure

The scale is characterized by three sectors:

Sector «LOW» — psychophysiological support for self-control is very weak. It can be easily adjusted by a specialist during the conversation. The combination of the indicator of this sector and the «weakened» sector of the second scale — a good prerequisite for a frank conversation, and in the case of the guilt of the subject — for obtaining a confession from him.

Sector «NORM» — the testing process does not disturb the subject, he is in a relatively calm state, which can be caused by confidence in the safety of the testing procedure, since mastering self-regulation methods guarantees him the absence of any troubles. This is possible if the polygraph specialist during the pre-test conversation did not convince the respondent that any self-regulation is clearly recorded on the polygraph and it will not be difficult to notice it.

Sector «HIGH» — psychophysiological efforts of self-control are high, close to the functional limit of the subject. In this case, aggression towards the testing procedure is possible (pulling off electrodes, etc.). This condition is usually caused by the high alertness of the subject or fear of giving out unwanted information.

When determining the state of the subject, a comprehensive assessment of the information is most effective.

If the level of control is weakened(scale No. 2) and the functional reserves that provide it are below the norm (scale No. 3), then the behavior of the subject is easily corrected from the outside. With such a combination of scale indicators, it was possible to obtain sincere confessions even in cases where the subject had undergone anti-polygraph training in special structures.

If the level of self-control is high, and the indicators of the third scale are within the range of «normal» or «high», then it is unlikely that the subject will «talk» and receive reliable information from him.

Many years of experience with these scales allows us to conclude that taking into account their indicators in practice greatly increases the capabilities of the polygraph.

sovremennie kompyuternie sistemi instrumentalnoidetekcii 3
Final form of presentation of results in the computer

Even a specialist with little experience, using this assessment system, is able to feel the inner world of a suspect, determine his functional state, predict and, moreover, identify possible resistance to the testing procedure, and, if favorable conditions arise, immediately use them to obtain incriminating information.
Three independent intelligent units have been introduced into the Chris and Reef computer systems for the first time in world practice. These polygraphs have a number of original solutions in the system unit and data acquisition sensors. They are the first in the world to use a new type of sensor to register mechanical counteraction methods. The original technical solution used in it made it possible to create a sensor that has no analogues in the world. Its secrets were passed on to representatives of the Lafayette company and received a positive assessment. Now they have been introduced into the American Lafayette and Oxyton polygraph systems.

In the external respiration channels, two types of sensors are used: capacitive and piezoceramic. The manufacturer is especially proud of the arterial pressure channel, which records the dynamics of blood pressure both in the usual classical version (without using a cuff), and a piezoceramic transducer.

In order for a polygraph examiner to conduct personnel checks, a set of tests has been additionally introduced, called the «polygraph examiner's workplace» (11 tests in total). It includes the following computer tests: a personal questionnaire, Mini — Mult (71 questions); the SAN method (well-being, activity, mood); graphological analysis (computer analysis of written speech); the Spielberg — Khanin test (personal and reactive anxiety); the Thomas test (ability to react in a conflict situation); the Jovaishi questionnaire (professional orientation of the individual); a modified eight-color Luscher test; the Aseinger test (aggressiveness test of personality); the Leonhard — Shminek test (accentuation questionnaire); the 16-factor Cattell personality questionnaire form C; a standardized method of personality research (Smil — 566); and shortened Smil — 398).

The use of tests by a polygraph examiner with a basic psychological education will significantly increase the effectiveness of professional selection.

High scientific and technical support for polygraph systems allowed the manufacturer to win 9 competitions in five foreign regions, including the United States. The executive vice president of the company representing the US government, who held the competition, Daniel Berkon, wrote in conclusion: «… large-scale studies of your polygraphs conducted by American specialists, including experts from the US Department of Defense, as a result of tests, established that they meet American standards, and thus they are recommended for delivery within the framework of American technical assistance for the project to ensure personnel safety. As a result of this competition, for the first time in the history of the United States, they purchased 18 Russian polygraphs.

    Мы используем cookie-файлы для наилучшего представления нашего сайта. Продолжая использовать этот сайт, вы соглашаетесь с использованием cookie-файлов.
    Принять