One of the leading indicators of the state of the central nervous system in the assessment of emotional tensions is the skin reaction (CR). Currently, two types of KR are allocated: the phasic and tonic. The Fazic Kyrgyz Republic (from the word "phase" is a variable value) - this is the response of the central nervous system to some short situational stimulus, which is called the reaction to the novelty of information. But, if you suspect continuously say: "You raped", then after several repetitions, the response will begin to decline and will soon cease at all.

Reduced indicators may occur after the fourth-fifth presentation. This phenomenon is based on "addictive" to a significant signal. It is determined by the level of motivation in concealing information, the type of human nervous system, its functional state.

The tonic skin reaction is a slow change in skin resistance or skin potential (voltage), which characterizes the nervous emotional state. If a person is unexpectedly placed in a stressful situation, then the Tonic Kyrgyz Republic will restructure within 2-3 minutes. Two or three minutes - this is the time of delaying the tonic reaction to the emotional stimulus. The magnitude of the skin resistance, which was actually observed in the stressful situation, changed from 300-600 com by 1-0.1 com. At the first stage of the study of the skin reactions, the researchers delimited techniques according to the measurement method. If the voltage between the two parts of the biological entrance is recorded, then it is called the skin-galvanic reaction (kGR) by the name of the scientist L. Galvani, who first observed this phenomenon. Sometimes this procedure is called electrodermography (from the Greek word Derma-skin).

The issue of studying the Cross reaction of the Kyrgyz Republic in the conditions of a laboratory and production experiment is devoted to a significant number of works as we (I.S. Condor, 1980, N. Lyonov, 1980, A.A. Kraklis, A.A. Aerdersons, 1982, and others .) and abroad (Wang 1961, Codor1963, EDELBERY 1964, HORI 1982, etc.). The history of the discovery of this phenomenon refers to the end of the nineteenth century, when in 1888, Ch. Feroes in 1889 I.R. Tarkhanov for the first time set the relationship between the level of skin resistance (skin potential) and the psycho-physiological state of the body.

In his work, presented at the meeting of the St. Petersburg Society of Psychiatrists and Neuropathologists, I.R. Tarkhanov said that any irritation applied to man, after some time the hidden period causes a strong change in the level of recorded indicators. Moreover, irritations are not necessarily associated with the skin itself. Even mental performing an arithmetic action causes significant changes in skin potential. In this case, the magnitude of the deviation depends on the state of the subject and the depth of its imagination. With the development of fatigue, the amount of response is significantly reduced. In the future, the discovery made by I.R Tarkhanov was reflected in world literature as the "Phenomenon of Tarkhanov", which consists in the fact that with the help of a sensitive galvanometer, the electrical potential of the skin surface was measured under various states of the body under study. In parallel with Tarkhanov, almost at the same time, Feroes revealed a similar dependence in the change in skin resistance. Such scientists like V.P. Gorez, (1943), S. Duret R. Duret, (1956) and others. Conducted a comparative estimate of two techniques for measuring the skin resistance and skin potential.

The subjects simultaneously registered the KR and electrical resistance with various sound, light, pain stimuli. They found that the curve forms are practically identical. Despite the fact that from the day of the first serious study of the skin has passed more than 100 years, the issue of the mechanism of the skin-galvanic reflex remains rather controversial. So, in 1889 I.R. Tarkhanov came to the conclusion that the skin potentials arise due to the diverting of the biotok from the sections with a different amount of sweat glands. To implement your idea I.R. Tarkhanov was proposed a special technique for the leading of the skin. As points of imposing electrodes, they recommended the palm and back surfaces of the brush and the forearm of the person. The mechanism of the occurrence of the skin potential, as I.R. Tarkhanov, lies a change in the intensity of sweat selection under the influence of the central nervous system. Tarkhanov Theory about the origin of the Kyrgyz Republic was questioned in 1963 (Zyerina, Skoril, Saurek). Studying the speed of distribution of the Kyrgyz Republic, they found that in the upper limbs it is 154.9 cm / s, and in the lower-71.6 cm / s. In connection with these data, it is quite justified the assumption that the basis of the occurrence of the Kyrgyz Republic will not be interconnected, the more functions of the sweat gland. Since their excretory processes are too inert compared to the speed of the Kyrgyz Republic.

The independence of the origin of the Kyrgyz Republic from the functional state of the sweat glands was demonstrated by the works of WilCott (1957). Exploring at the same time sweating, electrical resistivity of the skin and skin potential with palms of 35 subjects during tests on the oral solution of mathematical problems, WilCott et al. Found that the change in the electrical resistance occurs earlier by 1.1 seconds than sweating. It was found that the time of delaying the Kyrgyz Republic in the same test practically constantly. Despite the series of contradictory and even often excluding each other theories about the origin of constant potential, the participation of the central nervous apparatus in this process does not cause any doubts. The skin reaction is closely related both with the general state of the central nervous system and its various departments.

By registering the area described by the KR Curve on both hands, Raevskaya et al. (1985) revealed asymmetry in the reaction, in a calm state, when a series of photo posts was presented, the Kyrgyz Republic was more pronounced on his left hand, and during the countdown of time intervals there were more indicators on Right hand. This is apparently due to the fact that in this case the left hemisphere is mostly activated. Studies conducted in the process of transition from wakefulness to sleep showed that during a fall asleep, the phase activity of the KGR decreases, reaching a minimum during sleep.

An attempt was made to study the daily rhythms of electrical resistance in order to establish its periodicals. So, Pytenfranz, Hellbrugge, Niggeschmid (1956), exploring the daily periodical periodic on 8 subjects, found that the rhythm of the oscillations of this resistance from 8 to 11 hours was significantly higher, and from 12-15 and 18-20 hours below the average level. The daily krivods of electrical resistance of children, in general, are similar to the curves of adults, although they were shifted to the left for 1-2 hours (in children morning maximum at 8 o'clock, in adults at 10 o'clock, a daily minimum, respectively, at 12 and 14 hours). The maximum "flattening" curve and the greatest stability in children was observed at 20-22 hours, and in adults after 24 hours. Skin reaction is one of those indicators that is a non-profitable indicator of the organism on the novelty of the stimulus. The Kyrgyz Republic arises only as a result of the mismatch of the received information from the expected, and not the result of "irritation" in the usual sense of the word. (E.N. Sokolov, 1960, 1962).

The age-related and individual-sex differences (E.N. Kutchak et al.). Studying changes in the resistance of human skin in the process of its development, it was established that the minimum figures are observed in newborns, and, starting from one year, the skin resistance gradually increases. In old age, a decrease in the Kyrgyz Republic is traced, reaching senior age The values \u200b\u200bare not much greater than that of newborns.

Research V.N. Mezishcheva (1929, 1936) revealed a direct connection between the magnitude of the stimulus and the amplitude of the Kyrgyz Republic at the same time in the work of A.I. Zingerman (1967) was shown the inverse relationship between the probability of signal appearance and the magnitude of the skin-galvanic reaction. The less likely to appear it, the greater the response of the Kyrgyz Republic. The skin reaction accompanies all human mental processes, especially if they are obvious emotional color, being a total biological effect, whose character is determined by the functional state. large number Organs and tissues of the body and allows in some cases it is quite subtly analyzing the psycho-physiological reactions of a person (A.K. Podbyakyakin, 1949, 1954; Timofeeva, 1957). In 1967, Lakte found that the Kyrgyz Republic may reflect the training of the body to the upcoming perception of information, taking into account the physiological characteristics of the person and the nature of motivation.

The study of the Kyrgyz Republic with various degrees of tension made it possible to identify the direct dependence of the magnitude of the change in the skin resistance from the value of emotional tension. Skin-galvanic reaction can be used not only as an indicator emotional state Human, but also, under the appropriate conditions, makes it possible to determine its magnitude. Larger by social significance An irritant (provided that the equal emotional stability of the body) will correspond to a more pronounced manifestation of the skin reaction.

The CR is based on nervous mechanisms reflecting, ultimately, both the magnitude of the irritant and the likelihood of its appearance (entropy). The nature of the response of the Kyrgyz Republic is largely determined by the functional level of the regulatory system, tired or cheerful man, having a pathology. To assess the informativeness of the Kyrgyz Republic, various methodological approaches were used. The delay time was studied (Dorrow 1967), the maximum amplitude (A.A. Kraklis, A.A. Aledersons, 1982), the duration and area of \u200b\u200bthe waves (P.V. Tarakanov, 1982). Each method has the right to exist, although, in our opinion, the measurement of the area of \u200b\u200bthe Kyrgyz Waves should be considered the most informative. Analyzing the results of studies of various authors on the Kyrgyz Republic, we see that, in some cases, when exposed to relatively identical sources of stress per person, the researchers came to exact opposite results. To identify the reasons for the inconsistency of the results obtained, a special study was carried out (V. A. Varlamov, 1974). Two groups of subjects participated in the experiment: emotionally stable and emotionally unstable, inadequately reacting to stress. The tonic and the phasic components of the kg were registered on the background of a gradually increasing neuro-emotional load (segment A - M Fig. 2). It was found that the tonic component of the Kyrgyz Republic with an increase in emotional stress changed unidirectional (the skin resistance decreased). At the same time, the phasic kr had a two-phase dependence on the magnitude of the emotional voltage (Fig. 2). At the first stage of the task, an increase in frequency and the amplitude of the oscillation of the Fazic Kyrgyz Republic was observed. Further, with the continuation of an increase in emotional stress, a decrease in the amplitude of the Kyrgyz Republic (Point M) was observed. These studies once again confirmed the need to be attentive to the functional state of a person in the study, strive to optimize its condition in otherwise Polygraph survey data will be significantly distorted.

Fig. 2. Measuring the frequency and amplitude of the Kyrgyz Republic with smoothly increasing and smoothly declining emotional voltage:

a - background,
b - maximum response at the stage of increasing emotional voltage,
c is the minimum reaction at the time of maximum stress,
d ~ maximum response at the stage of reducing emotional voltage,
e - termination of the emotional stimulus,
M - Maximum emotional tension

Analysis of data on the mechanism of occurrence and regulation of the skin reaction, its informative features showed that:
-tonic skin reaction is a reflection of the depth processes of functional restructuring in the central nervous system;
- the magnitude of the "answer" of the skin-galvanic reflex is directly depending on the novelty of the stimulus, the typological features of the highest nervous activity, the level of motivation of the surveyed and its functional state;
- The dynamics of the indicators of the Fazic CR may be the criterion of the degree of emotional overvoltage of the human functional system. If the further growth of emotional stress leads to a decrease in the Fazic Kyrgyz Republic, this indicates the limit functionality examined;
- methods of registration, measurement of the dynamics of the skin resistance, or skin potential, the vision of informativeness does not have differences;
- Informative signs of the CR Curve are common to any periodic curves.

When analyzing the Kyrgyz Republic, it is necessary to take into account the characteristics of the mobility of the nervous system of people with regard to regional and national characteristics. According to the KR Curption, it is impossible to determine, the representative of which nationality is tested, Georgian or Chechen, but the fact that they are representatives of the "southern" peoples, both temperamental, with a movable nervous system, can be determined. Indicators that can be used for subsequent analysis are presented in Fig. 3. These include the time of delaying reaction (segment A-b). Since the presentation of stimulating information, the surveyed time of the reaction is normally 1.2-3 seconds. The length of the ascending curve (C-B segment) characterizes the power of activating excitation processes. The descending curve (C-G) is the intensity of the inclusion of brake processes. The time for which the reaction reached the maximum (1d determines the mobility of the excitation processes.

Almost in all cases, when analyzing the curves of the Kyrgyz Republic, the maximum height of the curve (H) is measured, reflecting the power of the emotional response of the central nervous system of the surveyed incentive. High informativeness represents the area measured under the curve (s,). It is an integral indicator that combines amplitude (s) and the total duration of the T 1 curve. Carries information and negative phase of the main curve (P). Negative phase is part of a curve that

Fig. 3. Indicators characterizing the curve of the Kyrgyz Republic:

A - amplitude of the reaction,
In - time
C - stimulus,
a, b - the time of delay reaction,
b, in - the length of the "ascending" curve,
in, g - the length of the "downward" curve,
t, - the time for which the reaction has reached a maximum,
tG - the time for which the reaction came to the initial state,
h-amplitude curve,
S- area under the curve,
D - the top of the negative phase of the curve,
h-amplitude of the negative phase of the curve,
E, s - "fading" curves.

It is below the zero line and characterizes the degree of brake reactions of the central nervous system, designed to correct the excitation reactions. The negative phase curve (the vertex "D") is analyzed by the same indicators as the main (over the duration of amplitude, etc.) with the only difference that it characterizes the braking processes. The greater the amplitude H in the curve of the negative phase, the actively connected the system opposing, that is, the inhibitory excitation processes after their manifestation. The state of excitation caused by the presented stimulus cannot be constant, infinite.

The inclusion of braking mechanisms carries a protective function, since the long-term foundation of the human body in a state of excitation is undesirable, it is adversely affected by the system as a whole. If the brake mechanism is very powerful, then the curve "Speaks" zero level And goes into the "negative phase (Fig. 4 - curve 1b). Thus, the brighter the surveyed is expressed by the" negative "phase in the KR curve, the greater the possibility of suspect to control its condition in extreme conditions.

However, it should be remembered that there are exceptions related to individual features The observed or applied by the technique of countering. The descending part of the curve is a reflection of the inclusion of braking processes. The more powerful this process, the faster the excitation is compensated and the steeper the curve tends to the insulance (Fig. 4 - curve 1b). If the reaction is positive, i.e. The curve is at the top of the isolated, then its ascending part and amplitude are determined by the processes of excitation. Normally, the balance of excitation and brake processes is expressed by the ratio as 1.0: 1.2. Brake processes should prevail slightly over the processes of excitation, by about 5-10%. The presence of a powerful brake process has great importance For the normal functioning of the nervous system. but important role In response to stimulating information, the presence of consistency, balance, interaction of the processes of excitation and braking is also plays.

In the absence of balance and consistency, the braking included one day will affect the human body for a very long time, which can also lead to difficulties in the interpretation of the results obtained. This phenomenon can be traced on curve # 2B (Fig. 4). The aroused excitation (the vertex "A") was compensated by braking (b), which was not "disconnected" almost until the end of the registration of the reaction. In practice, opposite reactions (curve 3) are found. The curve from the top of "A" caused by increased excitement on the stimulus (N) is very slow

Fig. 4. Some species of the Kyrgyz Republic in the background and after the flow of the stimulus:

N - incentive

A, b, in, g - vertices of the curve,

Isketon.

returns to the initial level. This phenomenon is possible if the response, the braking process turns slowly, sluggishly, inadequately by the power of the excitation process. The absence of a balance of activating and depressing processes is traced in Fig. Al- after a standard response to the stimulus, the curve does not fade and does not return to the zero line. It appears several small bursts that continue almost the entire measurement period. It should be borne in mind that the greater the coherence of excitation and braking processes, the less additional vertices on the curve are traced.

The control system in the body is designed so that there is a certain imbalance of corrective processes. This is due to the fact that the commands from the "Center" on the inclusion of certain reactions come with a delay, and, therefore, there are some overstutivation. In our example (curve 4), this phenomenon is clearly visible. After the increase in the excitation process, which led to the appearance of the vertex "A", the brake reactions turn on. The curve sharply decreases, reaching an isolated. By the time the team arrives in the Center that the process of bringing the reaction of initiation to the original baseline is completed, the reverse command will be received - weaken the brake processes.

Time will pass, the curve "Scroll" the Basic line ( points b, in, D). And it will be "connected" a system that increases excitement, and the curve will go up, trying to achieve the original level. And again, due to the delay of commands, the "slipping" will occur, etc.

In this case, we are dealing with a system that is constantly in motion, never stopping. The amplitude of these "swings" is closely related to the values \u200b\u200bof emotional stress and is determined by the overall functional state of the subject. This explains the emergence of additional vertices on the curve or an increase in amplitude of the already existing earlier. In practice, you can find an increase in both the number of vertices and their amplitudes, although this phenomenon is not necessary.

Cases are possible when additional vertices of the curve are cleaned more clearly in the background before the testing starts (Fig. 4 - curve 5 of the vertices in and b). When starting testing, they decrease sharply or disappear at all. This is due to stress of waiting, which is based on a deficit of information on the verification procedure. This type The reactions are observed in people for whom the absence (deficiency) of information, its uncertainty causes greater emotional stress than the information itself (curve 5).

Fig.5 Different forms of the reaction of the Kyrgyz Republic in response to an incentive:
N-stimulus
A, vertices of the curve

The stress of the expectation can manifest itself in the repeated appearance of the "vertices" on the curve (curve 6B). This false signal, not carrying information on the presented incentive (question), is easily determined if it was preceded by a long time a relatively smooth section of the polygraphs. Specialist must be remembered that the "delay" of the appearance of a response to the presented question lies within 1.2-3 seconds from the moment of awareness of the information being examined by him if the recording of the results begins after asked question. Therefore, the "key" word in the question should stand at the end of the phrase. For example, you can build a phrase: "Did you kill a woman with a child?". The reaction of the Kyrgyz Republic can be obtained after the words "killed." In this example, it is the main (key) in the formation of emotional stress. This information could be submitted to the surveyed in another sequence: "Woman with a child you killed?". IN this issue The keyword stands at the end of the phrase. The response to it will appear after 1.2-3 seconds. If the "response" reaction on the KR curve will be observed after 4-6 seconds, or more, then it is caused by an incomplete incentive, but an associative memory of events related to its past, including criminal. If the basic information is included in the subject, and associative is aware of the surveyed temporary delays, the curve may have several vertices (Fig. 5-2 A, b). For example, this reaction may be if a citizen "M", previously convicted for rape, under the presentation of a significant question, the usual reaction begins after 1.2-2 seconds. After the "key" word, and at that moment he remembers the place of imprisonment, where he, by coincidence, miraculously managed to stay alive. This information is the stimulus that causes additional emotional stress. It is possible that these memories can be somewhat tightened in time. In this case, there is a second, rather powerful vertex (Fig. 5 - 3 b). In this example, with a citizen "M" there are cases when after the "key" word, he first recall the events in the zone (Fig. 5 - 4 A curve), and then the next crime committed by him (4 b).

Fig. 2. 22.Physical basis of Okulogram. The eyeball acts as a miniature battery, when it turns out the pole of this battery, the position is changed relative to the electrodes placed near the eyes. Changes in electric potential, which can be judged by the angle of rotation of the eyes (Hesetset, 1981).

Electrojulography(EOG) - Method for registering electrical activity that occurs when eye movement. The cornea eye has a positive charge relative to the retina, which creates a constant potential, which is called rootoretreen potential. When the position changes, this potential is reorienting (Fig. 2.22), which is fixed by the instrument.

When writing using a DC amplifier, you can get information about eye orientation information, when using the AC amplifier - only recording eye movements.

Fig. 2.23.The location of the electrodes for the Okologram.

The recording is made of calibration, determining the range of possible shifts. For this subject, they ask for ahead, up, down, to the sides. The line on the EOG at the moment when the view is still and is directed forward, is taken for zero. Very small electrodes are used, located at the points shown in Fig. 2.23. The skin and electrodes are prepared in the same way as in electroencephalography.

Electrojulography please

effective in conjunction with other methods. When evaluating the EEG, for example, it allows you to extract artifacts caused by eye movement.

Skin -galvanic reaction

Electric skin activity - skin-galvanic reaction(KGR) - determined by two ways. The first, proposed by S. Ferere (Fere) in 1888, is a measurement of skin resistance. The second is the measurement of the potential difference between the two points on the surface of the skin - is associated with the name I.R. Tarkhanova (1889).

The comparison of the CGR, measured according to the Ferre method and according to the Tarkhanov method, led to the conclusion that changes in the difference in skin potentials and skin resistance reflect the same reflex reaction fixed in various physical conditions (Kozhevnikov, 1955). Resistance changes are always a single-phase wave of reducing the source skin resistance. Changes in skin potentials can be expressed in the form of waves of different polarity, often multiphase. According to R. Edel-Berg (EDELBERG, 1970), the difference in skin potentials includes an epidermal component that is not related to the activity of sweat glands, while the conductivity of the skin does not have it, that is, reflects the state of the sweat glands.

When measuring skin resistance with external source The current attached negative pole to the palm, the latent period of resistance changes turns out to be 0.4-0.9 seconds more than the hidden period of changes in the difference in potentials. The dynamic characteristics of F-ZHAGC reliably reflect the rapid processes in the CNS. The nature and form of the tonic component are individual indicators and do not detect clear dependence on the type of activity (Kuznetsov, 1983).

Fig. 2. 24.Changes in the physiological functions of the subject at the occurrence of dorms (a) and when waking (b). 1.2 - EEG, leads 0, and 0 2 (left and right hemisphere respectively); 3.4 - kGR left and right hand; 5 - seismicactogram (signals appear when tapping the test on the sensor with a finger); 6 - ECG (Leutin, Nikolaev, 1989).

In the occurrence of the Russian Federation, two main mechanisms are involved: the peripheral (properties of the skin itself, including the activity of sweat glands) (Biro, 1983) and the transmitter associated with the activating and starting effect of the central structures (Lader, Motagu, 1962). Spontaneous RFR differ in the absence of external influence, and caused by the reflective reaction of the body to an external incentive.

To register kGR

used non-polarized electrodes that are usually superimposed on the palm and back surface of the hands, finger tips, sometimes on the forehead or feet feet.

The most effective kGR in

cumbling with other methods in assessing the emotional state of the subjects (Fig. 2.24).

All described methods for obtaining psychophysiological information have their advantages and disadvantages. Simultaneous use of several of them at once in one experimental situation allows you to get more reliable results.

However, modern psychophysiology was born when the French doctor Ferre first noticed that emotional situations The electrical properties of the skin are changed. Now we know that the Ferre indirectly observed the activity of the sweat glands.

The person has 2 - 3 million sweat glands, but their number in different parts of the body varies greatly. For example, on the palms and soles of about 400 sweat glands on 1 cm of the skin surface, on the forehead - about 200, on the back - about 60. The selection of sweat glands occurs constantly, even when it does not appear on the skin. During the day, it is distinguished near the liquid half liter. In severe heat, the loss of fluid can reach 3.5 l / h.
There are two types of sweat glands: apocryine and eccritine.

Apokrin Potion glands, located in the armpits and in groin, determine the smell of the body and react to stratum stimuli. They do not affect the regulation of body temperature.

Ecrine Potomy glands are located along the entire body surface and distinguish between the usual sweat, the main components of which are water and sodium chloride. Their main function is thermoregulation, i.e. Maintaining a constant body temperature. Heat is formed when cutting muscles and with metabolism. Our body seeks to maintain the inner temperature at a constant level of about 36-37 ° C by recoiling heat with exhaled air and through the skin. One of the means of increasing skin heat transfer is thermoregulation sweating.

All these reactions control the reflex center, which is in the hypothalamus and reacts to the blood temperature. The reflex sweating occurs automatically before the body begins to be at risk overheating.

Other eccrint glands react not so much on temperature changes as the external stimuli and stress. These sweat glands are focused on the palms and soles, as well as to a lesser extent, on the forehead and under the mouse. The unit of the glands is not absolute, but relative. Under conditions of strong heat, "emotional" glands may respond to it, and thermostat iron regulatory glands may be responsible for it.

History of the question

In 1888. year Dr. Ferre described the following case. The patient with a hysterical anorexia, which he tactically names Madame X, complained about the sensations of electric tingling in the brushes and feet. Ferr noticed that these sensations were intensified when the patient inhaled some smell, looked at a piece of colored glass or listened to the sound of the camera. We do not know whether in the patient of tingling in the limbs, but during the Ferne survey found that when the weak current is passed through the forearm, systematic changes occurred in the electrical resistance of the skin. Two years later, Tarkhanov independently showed that similar electrical shifts can be observed without an external current application. Thus, it opened the skin potential and, in addition, it has established that this potential changes both with internal experiences and in response to sensory irritation.

Currently, the EAC unites whole line Indicators: Leather potential level, skin potential response, spontaneous skin potential reaction, leather resistance level, skin resistance reaction, spontaneous skin resistance reaction. The indicators of the skin were also used as indicators: level, reaction and spontaneous reaction. In all three cases, the "level" means the tonic component of the EAC, i.e. long-term changes in indicators; "Reaction" - the phasic component of the EAC, i.e. Fast, situational changes in EAC indicators; Spontaneous reactions are short-term changes that do not have a visible connection with external factors.
The origin and value of the EAC. The electrical activity of the skin is mainly due to the activity of sweat glands in the skin of a person, which in turn are under the control of the sympathetic nervous system.

In psycho-physiology, the electrical activity of the skin is used as an indicator of "emotional" sweating. As a rule, it is recorded from the tips of the fingers or palm, although it is possible to measure with the soles of the legs and from the forehead.

Research by physiologists at the end of the 19th century it was found that between the two electrodes directly applied to the skin, there is a potential difference due to local metabolism, the state of vessels and hydrophilicity of the skin. Skin areas rich in sweating glands, electronegative, and poor them are electropositive. Under the influence of pain, mental tension, the excitation of analyzers, the potential difference will change. This effect is open to Russian physiologist I.R. Tarkhanov in 1889 is usually between electrodes that are at a distance of 1 cm from each other, the potential difference Δφ is 10-20 mV. Under the influence of irritants Δφ grows up to dozens and hundreds of Millivolt. To remove the potentials, electrodes from zinc or silver are used and have a form of disks with a diameter of ~ 10 mm. For better contact, an electrically conductive paste is used. Previously, the paste was made of kaolin and a saturated solution of ZNS in water. Currently, industrial manufacture paste is used. The measurement circuit is shown in the figure. It can be seen that the compensation method is used. To measure the key 1. The key 2 is turned on randomly. Then the retail is reduced to zero, shown by an ammeter in the measuring circuit. If it does not work, the key switching 2. Then the object irritant is supplied and through the latent period (which is 1 to 3 c) register the skin-galvanic reaction to the stimulus. Such a procedure is called a leather-galvanic reaction in Tarkhanov.

The skin-galvanic reaction can be recorded according to the method of French doctor K. FERE. For this technique, electrical resistance is measured between two skin points. Under the influence of the irritant, the electrical skin resistance is changing after the expiration of the latent time. Both methods give identical results when registering a leather-galvanic reaction (kGR).

Informative opportunities kGR.

The electrical conductivity of the skin depends on the state of the vegetative nervous system. The factors determining the electrical conductivity are the activity of sweat glands, the permeability of biological membranes, hydrophilicity of the skin, blood supply. Impact, under the influence of which the electrical conductivity changes: painfulness, neuropsychic stress, afferent incentives (light, sound). The change in the electrical resistance of the skin is denoted as KGR, since it is accompanied by a change in the electroplating potential of the skin. It is carried out on constant voltage.

The skin-galvanic reactions are highly nonspecified, as they can be associated both with complex neuro-endocrine shifts, and with changes in information flows in the central nervous system. When the sympathetic system is excited, the skin resistance decreases (or the negative potential of the electrode increases). In parasympathetic reactions, the opposite occurs.

Piloters when flying through Parabol Kepler were observed fluctuations in electrical resistances caused by the effect of overloads, intermitted with immunity states. Schizophrenic observed spontaneous skin-galvanic reactions. Along with these relatively rapid reactions, there are also slow potential changes (hour, daily). In a dream, the resistance grows. When the vestibular apparatus is excited, the resistance decreases. RAG is considered an indicator of the vigilance and consciousness of the pilot. With this method, emotions are recorded - excitation, fright, fear, etc.

The RAG method was used on spacecraft during medical research and control of the state of astronauts. When flying at "East 3" and "East 4" with this method, slow fluctuations in leather-galvanic potential were recorded, and at "East 5" and "East 6" - rapid fluctuations. This method also has certain difficulties in the implementation. They are associated with an increase in electrical resistance due to the contact disorder with the skin and at the expense of polarization phenomena. At pilots and cosmonauts, the electrodes for the registration of kGR are imposed on the foot - the back and plantar parts. Elastic bandage electrodes fix. The nonspecificity of the skin-galvanic reactions dictates the need for their constant comparison with other physiological indicators, with the recording of radio engineering and television image. For example, on the record of the skin-galvanic reaction V.V. The carving signal coincided with its awakening from sleep, which was controlled by the opening of the eyes. The latter was registered by the method of electroculography (EOG).

Electric skin activity - skin-galvanic reaction(KGR) - determined by two ways. The first, proposed by S. Ferere (Fere) in 1888, is a measurement of skin resistance. The second is the measurement of the potential difference between the two points on the surface of the skin - is associated with the name I. R. Tarkhanova (1889).

A comparison of the KGR, obtained according to the Ferre method and the method of Tarkhanov, led to the conclusion that changes in the difference in skin potentials and skin resistance reflect the same reflex reaction fixed in various physical conditions (Kozhevnikov, 1955). Resistance changes are always a single-phase wave of reducing the source skin resistance. Changes in skin potentials can be expressed in the form of waves of different polarity, often multiphase. According to R. Edelberg (edelberg, 1970), the difference in skin potentials includes an epidermal component that is not associated with the activity of sweat glands, while the conductivity of the skin does not have it, that is, reflects the state of the sweat glands.

When measuring the skin resistance with an external source of current attached negative pole to the palm, the latent period of resistance changes turns out to be 0.4-0.9 seconds more than the hidden period of changes in the potential difference. The dynamic characteristics of the Fazic CGR reliably reflect the rapid processes in the CNS. The nature and form of the tonic component are individual indicators and do not detect clear dependence on the type of activity.

In the occurrence of the Russian Federation, two main mechanisms are involved: the peripheral (properties of the skin itself, including the activity of sweat glands) (Biro, 1983) and the transmitter associated with the activating and starting effect of the central structures (Lader, Motagu, 1962). Distinguish spontaneous kGR, developing in the absence external influenceand caused by a reflective response of the body on an external stimulus.

For the registration of RAGs use non-polarized electrodes, applied usually to the palm and the back surface of the hands, finger tips, sometimes on the forehead or feet feet.

The most effective kGR in combination with other methods in assessing the emotional state of the subjects (Fig. 2.24).

Fig. 2. 24.Changes in the physiological functions of the subject at the occurrence of dorms (a) and when waking (b).

1, 2 - EEG, leads 0 1 and 0 2 (left and right hemisphere, respectively); 3, 4 - kGR left and right hand; 5 - seismicactogram (signals appear when tapping the test on the sensor with a finger); 6 - ECG (Leutin, Nikolaev, 1989).

All described methods for obtaining psychophysiological information have their advantages and disadvantages. Simultaneous use of several of them at once in one experimental situation allows you to get more reliable results. Additional use of psychological tests also improves the efficiency of the use of physiological methods.