) (English) galvanic skin response) - bioelectric reaction recorded from the surface of the skin; as an indicator of nonspecific activation is widely used in psychophysiology. Syn. psychogalvanic reflex, electrical activity of the skin (EAS). GSR is considered as a vegetative component indicative reaction, defensive, emotional and other reactions of the body associated with sympathetic innervation, mobilization of adaptive-trophic resources, etc., and is a direct effect of the activity of the sweat glands. GSR can be recorded from any area of ​​the skin, but best of all - from the fingers, hands, and soles of the feet.

The widespread use of GSR for research and practical purposes began with fr. neuropathologist K. Feret, who discovered that when a weak current is passed through the forearm, changes occur in electrical resistance skin (1888), and grew up. physiologist I.R. Tarkhanov (Tarkhnishvili, Tarkhan-Mouravi), who discovered the skin potential and its change during internal experiences and in response to sensory stimulation (1889). These discoveries formed the basis for 2 main methods for recording GSR - exosomatic(skin resistance measurement) and endosomatic(measurement of the electrical potentials of the skin itself). Later it turned out that the methods of Feret and Tarkhanov give different results.

IN Lately many psychophysiologists oppose the very term “GSR” and replace it with a more precise one electrical activity of the skin(EAK), uniting whole line indicators that react differently depending on the nature of the stimulus and the internal state of the subject. EAC indicators include skin potential level(CPC, or SPL), skin potential reaction(RPK, or SPR), spontaneous reaction of skin potential(SRPK, or SSPR), skin resistance level( , or SRL), skin resistance reaction(RSK, or SRR), skin conductivity level(UPrK, or SCL), etc. In this case, “level” means tonic activity (relatively long-term states), “reaction” - phasic activity (short, within a few seconds, responses to stimuli) and “spontaneous” - reactions that are difficult to associate with k.-l. irritant. The level of tonic electrocutaneous resistance is used as an indicator of the functional state of the c. n. s: in a relaxed state, e.g. during sleep, skin resistance increases, and when high level activation decreases. Phasic indicators react sharply to the state of tension, anxiety, strengthening of mental activity. (I. A. Meshcheryakova.)

Large psychological dictionary. - M.: Prime-EVROZNAK. Ed. B.G. Meshcheryakova, acad. V.P. Zinchenko. 2003 .

See what "GALVANIC SKIN REACTION" is in other dictionaries:

Galvanic Skin Response- Galvanic skin response (GSR) is a bioelectrical activity recorded on the surface of the skin, caused by the activity of the sweat glands and acting as a component of the orientation reflex, emotional reactions of the body... Psychological Dictionary

galvanic skin response- (syn.: psychogalvanic reaction, galvanic skin reflex, psychogalvanic reflex, Tarkhanov phenomenon) a change in the potential difference and a decrease in electrical resistance between two areas of the skin surface (for example, the palm and ... ... Large medical dictionary

GALVANIAN SKIN RESPONSE- Measuring the electrical sensitivity of the skin with a galvanometer. Two methods are used: the Feret measurement, which records changes in skin resistance when passing a weak electric current, and the Tarkhanov measurement, in which... ... Explanatory dictionary of psychology

GALVANIAN SKIN RESPONSE- – bioelectric reaction recorded from the surface of the skin. Its value is the unconditionality of the reaction... Modern educational process: basic concepts and terms

Galvanic skin response- change in electrical resistance of the skin depending on the degree of physiological arousal and, presumably, emotional state. Used in lie detectors. Synonyms: Tarkhanov Phenomenon, Feret Phenomenon, psychogalvanic reaction, etc...

An indicator of skin electrical conductivity. It has physical and tonic forms. In the first case, GSR is one of the components of the orienting reflex that arises in response to a new stimulus and fades with its repetition. Tonic form of GSR... ...

GALVANIAN SKIN RESPONSE (GSR)- an indicator of electrical conductivity of the skin, estimated by the value of the electrical resistance of the skin or the difference in electrical potential between two points of the skin. The most pronounced GSR occurs when it is recorded from the fingertips, palms and back... encyclopedic Dictionary in psychology and pedagogy

- (galvanic skin reaction GSR) bioelectrical activity recorded on the surface of the skin and caused by the activity of the sweat glands, an indicator of the electrical conductivity of the skin. Acts as a component of the reactions of the emotional body associated with... ... Great psychological encyclopedia

galvanic skin reflex Large medical dictionary

psychogalvanic response- see Galvanic skin response... Large medical dictionary

The invention relates to the field of medicine and medical technology, in particular to methods and devices for diagnosing the condition of a living organism by the electrical conductivity of the skin, and can be used in experimental and clinical medicine, as well as in psychophysiology, pedagogy and sports medicine. The invention makes it possible to eliminate interference caused by human movement artifacts, as well as those caused by non-biological reasons (various electrical interference and hardware noise). The method is characterized by analyzing the shape of each pulse in a sequence of pulses in the frequency band of the phasic component. To do this, the first and second time derivatives of the logarithm of the electrical conductivity of the skin are recorded. The magnitude of the trend caused by the tonic component is determined, and the value of the first derivative is adjusted by subtracting the trend value from it. Next, the arrival time of the first derivative pulse is determined at the moment the value of the second derivative exceeds the threshold value, and then the shape of the said pulse is analyzed. If the parameters of this form are met, the established criteria are classified as pulses of the phasic component, and if not met, they are classified as artifacts. 2 s. and 9 salary, 6 ill.

The invention relates to the field of medicine and medical technology, in particular to methods and devices for diagnosing the condition of a living organism by the electrical conductivity of the skin, and can be used in experimental and clinical medicine, as well as in psychophysiology, pedagogy and sports medicine. It is known that the electrical conductivity of the skin of a living organism is a sensitive indicator of its physiological and mental state, and the parameters of the conductivity response to external influence, the so-called galvanic skin response (GSR), allows you to assess the psychophysiological status of the individual. When studying GSR, indicators of the tonic and phasic components of electrodermal activity (EDA) are distinguished. Tonic activity characterizes changes in skin conductance that occur relatively slowly over a period of several minutes or more. Phasic activity is processes that occur much faster against the background of tonic activity - their characteristic times are a few seconds. It is phasic activity that largely characterizes the body’s response to external stimulus and is further referred to as the phasic component, or GSR. Known methods for recording GSR involve placing a pair of electrodes on the skin of the test subject, connected to a source of probing current and a current recorder in the electrodes - current source circuit. The reaction occurs when the sweat glands release secretions and short-term pulses of electrical current occur in the circuit. Such impulses are generated either spontaneously or as a result of a stressful or other stimulus. Known devices for recording GSR include a current source connected to the electrodes, as well as a unit for recording changes in time of the electrical signal and processing it. Signal processing consists of isolating the phasic component against the background of the tonic component. This could be achieved, for example, in a unit using a bridge circuit and a series of individually zeroed DC amplifiers. The value of the tonic component (hereinafter referred to as trend) is calculated analoguely and then subtracted from the signal. The base line on the plotter is shifted to zero by this amount. In another known device, the relative level of the phasic component compared to the tonic component of electrodermal activity is highlighted by a circuit containing high- and low-pass filters at the outputs of the corresponding amplifiers, as well as a division circuit. It should be noted that the above-mentioned method and devices for recording galvanic skin response do not provide means for analyzing the phasic component pulses themselves, while they can provide additional information about the state of the subject. The closest to the claimed method is the method for recording galvanic skin response, implemented in the device. The method involves attaching two electrodes to the human body, applying electrical voltage to them, recording changes in time of the electric current flowing between the electrodes, and recording current pulses in the frequency band of the phasic component of electrodermal activity. The prototype of a device for recording galvanic skin reactions is a device that implements the above method. It has electrodes with means for attaching them to the skin, connected to the input device, means for isolating signals in the frequency bands of the phasic and tonic components of electrodermal activity, means for detecting pulses of the phasic component, means for reducing the amplitude of impulse noise, as well as a recording unit. However, the above-mentioned method and device are not free from artifacts that are superimposed on the time sequence of GSR signals and are similar to the pulses of the phasic component. These artifacts are, for example, a consequence of uncontrolled human movements during registration (so-called motion artifacts (MA)). Noise may also appear in the signal due to changes in the contact resistance between the electrodes and human skin. The noise mentioned above, including IM, may have characteristic frequencies comparable to the phasic component, which makes their identification and accounting a special problem. Previously, this problem was solved by installing special sensors, in addition to electrodermal ones, on the human body, which complicates the experiment (R.NICULA. - “Psychological Correlates of Nonspecific SCR”, - Psychophysiology; 1991, vol. 28. No l, p.p. 86-90 ). In addition, the tonic component has minimal characteristic times of the order of several minutes. These changes must be taken into account, especially in cases where the amplitude and frequency of the phasic component are reduced, and tonic changes are maximum. This process is also typical for hardware drift of the measuring path, and can be erroneously interpreted as an information signal. The objective of the present invention is to create a method for recording GSR and a device for its implementation, free from interference caused by artifacts of human movement, as well as interference caused by non-biological reasons (technogenic and atmospheric electrical discharges and hardware noise). This problem is solved without the use of any additional devices similar to those described in the above-mentioned work by R.NICULA. Information about interference is extracted directly from the GSR signal itself, and the technique is based on a detailed analysis of the shape of each electrical pulse in the sequence of pulses coming from the electrodes. It is known that the impulse of the phasic component is a spontaneous short-term increase in skin conductivity with a subsequent return to the original level. Such an impulse has a specific asymmetry of shape: it has a steep leading edge and a flatter trailing edge (see “Principles of Psychophysiology. Physical, Social, And Inferential Elements.” Ed. John T. Cacioppo and Louis G. Tassinary. Cambridge University Press, 1990, p.305). To determine the required parameters of this GSR pulse, the logarithm of the input signal is differentiated (for example, using an analog differentiator). The patented method involves attaching two electrodes to the human body, applying electrical voltage to them, recording changes in time of the electric current flowing between the electrodes and recording current pulses in the frequency band of the phasic component of electrodermal activity. The method is characterized by analyzing the shape of each pulse in a sequence of pulses in the frequency band of the phasic component. To do this, the signal is recorded in the form of a time derivative of the logarithm of the numerical value of the electric current, the magnitude of the trend caused by changes in the signal in the frequency band of the tonic component of electrodermal activity is determined, and the value of the first derivative is corrected by subtracting the trend value from it. Next, the second time derivative of the logarithm of the numerical value of the electric current is recorded, the beginning of the pulse of the said signal is determined by the moment the second derivative exceeds the threshold value, and then the compliance of the pulse shape with the established criteria is determined. If there is such a correspondence, the analyzed pulse is classified as a pulse of the phasic component, and if it is absent, it is classified as an artifact. The trend value can be determined as the average value of the first derivative over a time interval characteristic of the tonic component, mainly from 30 to 120 s. In addition, the trend value can be determined as the average value of the first derivative over a time interval of 1-2 s, provided that the values ​​of the first and second derivatives are less than specified threshold values ​​during this time interval. The arrival time of the first derivative pulse can be considered the moment when the second derivative exceeds the threshold value by at least 0.2%. When determining the pulse shape, the values ​​of the maximum (f MAX) and minimum (f min) values ​​of the first derivative minus the trend value, their ratio r, and the time interval (t x) between the minimum and maximum of the first derivative are recorded. In this case, the moments of achieving the maximum and minimum values ​​of the first derivative are determined by the moment the sign of the second derivative changes. The criteria for the analyzed impulse to belong to the signal of the phasic component of electrodermal activity can be the following inequalities (for a filtered signal): 0.5< f MAX < 10; -2 < f min < -0,1; 1,8 < t x < 7; 1,5 < r < 10 Вышеприведенные существенные признаки патентуемого способа обеспечивают достижение технического результата - повышения помехозащищенности регистрации кожно-гальванической реакции в условиях реальных помех различного происхождения, а также артефактов движения самого испытуемого. Ниже описанные средства для реализации способа могут быть выполнены как приборным, так и программным путем и их сущность ясна из приведенного описания. Устройство для регистрации кожно-гальванических реакций содержит электроды со средствами их крепления, подключенные к входному устройству, средства для подавления импульсных помех, средства для выделения сигналов в полосах частот фазической и тонической составляющих электродермальной активности, средства для детектирования импульсов фазической составляющей и блок регистрации. Средства выделения сигнала в полосах частот тонической и фазической составляющих, средства для подавления импульсных помех и средства для детектирования импульсов фазической составляющей выполнены в виде последовательно подключенных к входному устройству фильтра нижних частот, блока преобразования логарифма входного сигнала в первую и вторую производные по времени и блока анализа формы импульсов, при этом выход последнего подключен к входу блока регистрации. Входное устройство может представлять собой стабилизированный источник электрического напряжения и резистор, подключенные последовательно к электродам, логарифмирующий усилитель с дифференциальным входным каскадом, при этом резистор шунтирует входы логарифмирующего усилителя. Блок преобразования логарифма входного сигнала в первую и вторую производные по времени может быть выполнен в виде первого и второго дифференциаторов и фильтра нижних частот, при этом выход первого дифференциатора подключен к входам второго дифференциатора и фильтра нижних частот, выходы которых являются выходами блока. Блок анализа формы может включать средства для определения максимальной скорости изменения проводимости на переднем и заднем фронтах анализируемого импульса, средства для определения асимметрии его формы, средства для определения ширины импульса, средства для сравнения упомянутых величин с установленными пределами для выработки сигнала принадлежности анализируемого импульса сигналу фазической составляющей электродермальной активности. Блок преобразования входного сигнала в первую и вторую производные по времени от его логарифма и блок анализа формы импульсов могут быть выполнены на базе компьютера, подключенного к входному устройству через аналого-цифровой преобразователь. По сведениям, которыми располагают изобретатели, технический результат - повышение достоверности при выделении импульсов фазической составляющей очевидным образом не следует из сведений, содержащихся в уровне техники. Изобретателям не известен источник информации, в котором бы раскрывалась применяемая методика анализа формы сигнала, позволяющая разделять полезные сигналы импульсов фазической составляющей и артефакты, в том числе обусловленные движениями испытуемого. Отмеченное позволяет считать изобретение удовлетворяющим условию патентоспособности "изобретательский уровень". В further invention is explained by a description of specific, but not limiting, embodiments of the invention. In fig. 1 shows a functional diagram of a device for recording galvanic skin reactions in accordance with the present invention; in fig. 2 - real example forms of the original signal (a) and the results of its processing by the device according to the invention (b, c, d); in fig. 3 - hardware implementation of the pulse shape analysis unit; in fig. 4 - timing diagrams explaining the functioning of the shape analysis unit; in fig. 5 - example of implementation of a synchronization block; in fig. 6 is an example of a computer implementation of a device using digital signal processing; It is convenient to explain the patented method for recording galvanic skin response using examples of the functioning of devices for its implementation. The device for recording galvanic skin response (Fig. 1) includes an input device 1 connected to electrodes 2, 3 for connection to human skin 4. Electrodes can be made in various versions, for example, in the form of two rings, a bracelet on the wrist and a ring, a bracelet with two electrical contacts. The only requirement for them is that the electrodes must provide stable electrical contact with the skin of the test subject. Electrodes 2, 3 are connected to a stabilized voltage source 5 through resistor R 6, and the resistor itself is connected to the input of a differential logarithmic amplifier 7, the output of which is the output of input device 1 and is connected to the input of low-pass filter 8. The output of the filter 8 is connected to the input of the first differentiator 9. The output of the latter is connected to the input of the second differentiator 10, the output of which is connected to the input 11 of the pulse shape analysis unit 12. In addition, the output of the first differentiator 9 is connected directly to block 12 through input 13, and also through low-pass filter 14 to another input 15 of shape analysis block 12. The signal from the output of the mentioned low-pass filter 14 is used in block 12 to compensate for the tonic component of the GSR. The cutoff frequency of the 8 low-pass filter is about 1 Hz, and the cutoff frequency of the 14 low-pass filter is about 0.03 Hz, which corresponds to the upper limits of the frequency bands of the phasic and tonic components of the EDA. The output of the pulse shape analysis unit 12 is connected to the recording unit 16. The invention can be implemented in both hardware and software. In both cases, the analysis of the pulse shape of the phasic component of the EDA, which makes it possible to separate them from motion artifacts and interference, is carried out using characteristic signal parameters, which are then compared with acceptable limits. These characteristic parameters include: the maximum steepness of the leading and trailing edges of the pulse: expressed as the maximum (f MAX) and minimum (f min) values ​​of the first derivative of the logarithm of the input signal (minus the trend); pulse width tx, defined as the time interval between the moments of reaching the maximum and minimum values ​​of the first derivative; the ratio of the absolute values ​​of the first derivative (minus the trend) at the maximum and minimum: r = |(f MAX)|/|(f min)|. This value of r is a measure of the asymmetry of the analyzed pulse. Thus, the conditions for attributing the analyzed pulse to the pulse of the phasic component of the EDA, and not to motion artifacts and interference, are the inequalities: m 1< f MAX < m 2 ; m 3 < f min < m 4 ; r 1 < r < r 2 ;
t 1< t x < t 2 "
Where
m 1, m 2 - the smallest and largest permissible values ​​of the first derivative (minus the trend) at the maximum, %/s;
m 3, m 4 - the smallest and largest permissible values ​​of the first derivative (minus the trend) at a minimum, %/s;
t 1, t 2 - minimum and maximum time between extrema of the first derivative, s;
r 1, r 2 - the minimum and maximum value of the ratio r. It has been established that these limits vary greatly both from one subject to another, and for the same person during different measurements. At the same time, when statistically processing the research results, it was found that from 80 to 90% of the signals actually belong to GSR signals if the following numerical values ​​of the limits are used: m 1 = 0.5, m 2 = 10, m 3 = -2, m 4 = - 0.1, t 1 =1.8, t 2 =7, r 1 =1.5, r 2 =10. In fig. Figure 2 shows an example of processing a real GSR signal. Curve a shows the signal shape - U = 100ln (I measured) at the output of logarithmic amplifier 7; on curve b - the first U", and on curve c - the second U" derivatives of the signal shown on curve a. Since the circuit provides for the logarithm of the signal, after differentiation in elements 9 and 10, the numerical values ​​of the derivatives of the signal U" and U"" have the dimensions %/s and %/s 2, respectively. In the same place, Fig. 2 of curve d shows the result of recognizing the GSR signal on against the background of trend and interference according to the patented invention. The marks S 1 and S 2 show the signals corresponding to the time of appearance of the pulses of the phasic component. Noteworthy is the experimental fact that the pulse is externally similar to the marked marks S 1 and S 2 in the time interval 20 - 26. s (shaded area) is an interference. Checking the compliance of the pulse with the specified four criteria (*) is carried out by the shape analysis unit 12. The trend value can be determined as the average value of the first derivative over a time interval characteristic of the tonic component, mainly from 30 to 120 s. In addition, the trend value can be determined as the average value of the first derivative over a time interval of 1-2 s, provided that the values ​​of the first and second derivatives are less than specified threshold values ​​during this time interval. In the second option, the trend is determined more accurately, however, if there is a large amount of interference, the above conditions may not be met long time. In this case, it is necessary to determine the trend in the first way. In fig. Figure 3 shows as an example the hardware implementation of block 12. In this embodiment, the trend is determined by the average value of the first derivative over a time of 30 s. In fig. Figure 4 shows timing diagrams explaining the operation of individual elements of this block. Block 12 has three inputs 11, 13 and 15. Input 11, to which the signal of the second derivative U" is supplied, is the signal input of two comparators 17 and 18, and a zero potential is applied to the reference input of the latter. Inputs 13 and 15 are inputs differential amplifier 19, the output of which is connected to the signal inputs of the sample and hold circuits 20 and 21. The outputs of the comparators 17, 18 are connected to the inputs of the synchronization block 22, respectively to the inputs 23 and 24. The output 25 of the block 22 is connected to the clocking input of the sampling and storage circuit 20, as well as to the start input of the sawtooth voltage generator 26. Output 27 is connected to the clock input of the sample and hold circuit 21. The outputs of the sampling and storage circuits 20, 21, as well as the sawtooth voltage generator 26, are connected to the inputs of the comparison circuits 29, 30 and 31. In addition, the outputs of the circuits 20 and 21 are connected to the inputs of an analog divider 32, the output of which is connected to the input of the comparison circuit 33. The outputs of circuits 29, 30, 31, 33 are connected to the logical inputs of the And circuit: 34, 35, 36, 37, 38. In addition, the output 28 of the synchronization circuit 22 is connected to the strobe input 39 of the And circuit 34. The comparator 17 has an input for supplying a reference voltage V S1, which sets the threshold value of the second derivative, above which the analysis of the pulse shape begins. The reference inputs of the comparison circuits 29, 30, 31, 33 are also connected to reference voltage sources (not shown in the figure), which determine the permissible limits of the selected parameters. The indices in the names of these voltages (V T1, V T2; V M1, V M2; V R1; V M3, V M4) correspond to the above limits, within which the tested quantities must lie (see inequalities (*)). In the case of such a correspondence, a short pulse of logical “1” is generated at the output 40 of circuit 34. The operation of the pulse shape analysis unit 12 shown in FIG. 3 is illustrated by the diagrams of FIG. 4. Diagram a shows an example of a single pulse at the output of logarithmic amplifier 7. The following signals are supplied to the input of block 12: the first derivative signal to input 131 (diagram b), the first derivative signal averaged over 30 s to input 15, and the signal the second derivative goes to input 11 (diagram c). The averaging time was chosen to be the shortest, corresponding to the frequency range of the tonic component of the EDA. As a result, at the output of the differential amplifier 19 there is a voltage of value U", corresponding to the first derivative of the logarithm of the input signal, compensated for the trend value. The value of U" is numerically equal to the voltage increment per second, expressed in %, relative to the value of the tonic component (see Fig. 4, b). It is this signal that is analyzed by the rest of the circuit. The elements of block 12 are clocked by synchronization circuit 22 as follows. The signal from the output of the comparator 17 is a positive voltage drop that occurs when the voltage from the output of the differentiator 10 exceeds the threshold value V S1 (Fig. 4, c). The numerical value of the threshold voltage V S1 in volts is selected so that it corresponds to a change in the second derivative of at least 0.2%, as determined experimentally. This positive edge (Fig. 4, d) is the trigger strobe for the synchronization circuit 22. Comparator 18 (see Fig. 4, e) produces positive and negative voltage drops at its output when the input signal U"" crosses zero. After starting the synchronization circuit with a strobe pulse from comparator 17, short strobe pulses are generated for each edge of the signal from comparator 18. The first strobe pulse arrives at output 25 (Fig. 4, f) and is then fed to the sampling and storage circuit 20, which records the value of U" at the moment of reaching the maximum (Fig. 4, g). The second strobe (Fig. 4, h) arrives from the output 27 of the synchronization circuit 22 to the gating input of the second sampling and storage circuit 21, which fixes the value of U" at a minimum (Fig. 4, i). The first pulse is also supplied to the input of the sawtooth voltage generator 26, which generates a linearly increasing voltage after the arrival of the strobe pulse (Fig. 4, j). The signal from the output of the sawtooth voltage generator 26 is fed to the input of the comparison circuit 29. The output signal from circuit 20 is supplied to the input of comparison circuit 30. The signal from the output of circuit 21 is supplied to circuit 31. In addition, the signals from the outputs of circuits 20, 21 are supplied to inputs A and B of analog divider 32. The signal from the output of analog divider 32 is proportional the ratio of the input voltages U A /U B is supplied to the input of the comparison circuit 33. Signals from the outputs of all comparison circuits 29, 30, 31 and 33 are fed to the inputs 35, 36, 37, 38 of the logical AND circuit 34, which is clocked by a strobe pulse (see Fig. 4, k) supplied to the strobe input 39 from the output 28 of the circuit 22. As a result, a logical “1” pulse is generated at the output 40 of circuit 34 if a logical “1” signal is applied to all four inputs 35-38 during the arrival of a strobe pulse at input 39, the positive edge of which corresponds to the negative edge at output 28. Comparison circuits (items 29-31,33) can be implemented in any of the traditional ways. They produce a logical "1" signal if the input voltage lies within the range specified by the two reference voltages. All internal strobe signals are provided by synchronization circuit 22, which can be implemented, for example, as follows (see Fig. fig. 5). Circuit 22 has two inputs: 23 and 24. Input 23 is connected to the S-input of the RS flip-flop 41, which is switched to the single state by a positive edge from the comparator 17 (Fig. 4, d), i.e. when the value of the second derivative U"" exceeds the threshold level. The output Q of trigger 41 is connected to the inputs of logic AND circuits 42 and 43, thus allowing signals from trigger 44 and inverter 45 to pass through them. Input 24 receives a signal from comparator 18 (Fig. 4, e). The negative signal differential from input 24 is inverted by inverter 45 and, through circuit 42, is supplied to another one-shot 46, which generates a gate pulse at output 25 (see Fig. 4. h). A positive differential from input 24 turns trigger 44 into a single state, which in turn triggers one-shot 47, which generates a short positive pulse. This strobe pulse is supplied to output 27 of the synchronization circuit (Fig. 4, f). The same pulse is supplied to the input of inverter 48, the output of which is connected to the input of one-shot 49. Thus, circuit 49 is triggered by the falling edge of the pulse from output 47 and produces a third short gate pulse (see Fig. 4, k). This pulse is supplied to output 28, and is also used to reset RS flip-flops 41 and 44, for which it is supplied to their R inputs. After the passage of this pulse, the synchronization circuit 22 is again ready for operation until the next signal arrives at input 23. As a result of the above-described operation of the synchronization circuit 22, a short pulse of logical “1” is generated at the output 40 of the shape analysis unit 12 (see Fig. 3) under the condition that the analyzed parameters lie within the specified limits. It should be noted that in Fig. 2, d the labels S 1 and S 2 are the indicated pulses; for clarity, they are superimposed on the graphs of the first and second derivatives of the analyzed signal. The above describes the hardware implementation of means for isolating signals of the tonic component and pulses of the phasic component. At the same time, identifying the useful pulse of the phasic component against the background of noise and blood pressure can also be done programmatically. In fig. Figure 6 shows an example of a computer implementation of a device using digital signal processing. The device includes an input device 1 connected to electrodes 2, 3 for connection to human skin 4. The electrodes are connected through a resistor R6 to a source 5 of a stabilized constant reference voltage. The signal from resistor 6 is fed to the input device - operational amplifier 50 with high input and low output impedances, operating in linear mode. From the output of the amplifier 50, the signal is fed to the input of a standard 16-bit analog-to-digital converter 51 (ADC), installed in the expansion slot of an IBM-compatible computer 52. Logarithm and all further analysis of the signal are performed digitally. Using the ADC-converted values ​​of the current flowing between the electrodes (Imeas)> the first and second derivatives of the value 100ln(Imeas) are calculated. It is necessary to calculate the values ​​of the first derivative adjusted for the trend. The trend value is defined as the average value of the first derivative over a period of time from 30 to 120 s. Next, it is determined whether the analyzed pulse belongs to the GSR signal (checking the fulfillment of conditions (*)). If the shape parameters are met, the established criteria are classified as GSR pulses, and if they are not met, they are classified as artifacts. The described method and device can be used in various medical and psychophysiological studies, where one of the measured parameters is the electrical conductivity of the skin. These are, for example: simulators with skin resistance feedback for developing relaxation and concentration skills, occupational selection systems, etc. In addition, the patented invention can be used, for example, to determine the level of wakefulness of a vehicle driver in real conditions, characterized by the presence of numerous interferences. The implementation of devices can be easily carried out using a standard element base. The device version with digital signal processing can be implemented based on any personal computer, as well as using any microcontroller or single-chip microcomputer. The connection between the measuring part and the signal processing device (both analog and digital) can be carried out by any of known methods, both via a wired channel and wirelessly, for example, via a radio channel or an IR channel. There are many different embodiments of the device depending on the skill and professional knowledge, as well as the element base used, therefore the given diagrams should not serve as limitations in the implementation of the invention.

Claim

1. A method for recording galvanic skin reactions, including attaching two electrodes to the human body, applying electrical voltage to them, recording changes over time in the electric current flowing between the electrodes and recording current pulses in the frequency band of the physical component of electrodermal activity, characterized in that it is analyzed the shape of each pulse in a sequence of pulses in the frequency band of the physical component, for which the signal is recorded in the form of a time derivative of the logarithm of the numerical value of the electric current, the magnitude of the trend caused by changes in the signal in the frequency band of the tonic component of electrodermal activity is determined, and the value of the first derivative is corrected by subtracting from it, the trend value is recorded, the second time derivative of the logarithm of the numerical value of the electric current is recorded, the beginning of the pulse of the said signal is determined by the moment the second derivative of the threshold value is exceeded, and then the compliance of the pulse shape with the established criteria is determined and, if there is such compliance, the analyzed pulse is classified as a pulse of the physical component , and if absent, they are classified as artifacts. 2. The method according to claim 1, characterized in that the trend value is determined as the average value of the first derivative over a time interval, mainly from 30 to 120 s. 3. The method according to claim 1, characterized in that the trend value is determined as the average value of the first derivative over a time interval of 1 - 2 s, provided that the values ​​of the first and second derivatives are less than specified threshold values ​​during this time interval. 4. The method according to any one of claims 1 - 3, characterized in that the arrival time of the first derivative pulse is considered the moment when the second derivative exceeds the threshold value by at least 0.2%. 5. The method according to any of claims 1 - 4, characterized in that when determining the pulse shape, the values ​​of the maximum f m a x and minimum f m i n values ​​of the first derivative minus the trend value, their ratio r, the time interval t x between the minimum and maximum of the first derivative are recorded, with In this case, the moments of achieving the maximum and minimum values ​​of the first derivative are determined by the moment the sign of the second derivative changes. 6. The method according to claim 5, characterized in that the criteria for the analyzed impulse to belong to the signal of the physical component of electrodermal activity are the inequalities
0,5 < f m a x < 10;
-2 < f m i n < -0,1;
1,8 < t x < 7;
1,5 < r < 10. 7. Устройство для регистрации кожно-гальванических реакций, содержащее электроды со средствами их крепления, подключенные к входному устройству, средства для подавления импульсных помех, средства для выделения сигнала в полосе частот физической составляющей электродермальной активности, средства для детектирования импульсов физической составляющей, блок регистрации, отличающееся тем, что средства выделения сигнала в полосе частот физической составляющей, средства для подавления импульсных помех и средства для детектирования импульсов физической составляющей выполнены в виде последовательно подключенных к входному устройству фильтра нижних частот, блока преобразования входного сигнала в первую и вторую производные по времени и блока анализа формы импульсов, при этом выход последнего подключен к входу блока регистрации. 8. Устройство по п.7, отличающееся тем, что входное устройство представляет собой стабилизированный источник электрического напряжения и резистор, подключенные последовательно к электродам, логарифмирующий усилитель с дифференциальным входным каскадом, при этом резистор шунтирует входы логарифмирующего усилителя. 9. Устройство по п.7 или 8, отличающееся тем, что блок преобразования входного сигнала в первую и вторую производные по времени выполнен в виде первого и второго дифференциаторов и фильтра нижних частот, при этом выход первого дифференциаторв подключен к входам второго дифференциатора и фильтра нижних частот, выходы которых являются выходами блока. 10. Устройство по любому из пп.7 - 9, отличающееся тем, что блок анализа формы включает средства для определения максимальной скорости изменения сигнала на переднем и заднем фронтах анализируемого импульса, средства для определения асимметрии его формы, средства для определения ширины импульса, средства для сравнения упомянутых величин с установленными пределами для выработки сигнала принадлежности анализируемого импульса сигналу физической составляющей электродермальной активности. 11. Устройство по п.7, отличающееся тем, что фильтр нижних частот, блок преобразования входного сигнала в первую и вторую производные по времени и блок анализа формы импульсов выполнены на базе компьютера, подключенного к входному устройству через аналого-цифровой преобразователь.

Spheres practical application GSR method In psychological and psychophysiological studies requiring an integrative assessment of the functional state; To solve various applied problems in occupational psychology, psychophysiology, engineering psychology, etc., related to quantitative assessment of impact various kinds factors per person;

Areas of practical application of the GSR method To speed up the learning process various methods self-regulation of psychofunctional state; methods of self-regulation of psychofunctional state For research related to optimizing ways for a person to solve problematic issues and problem situations while performing professional activities.

Application of GSR parameters For quantitative assessment of all types of emotional manifestations observed both as a result of special influences in experiments, and as an indicator of subjective experiences; As a parameter of energy supply both for the entire organism as a whole and for individual systems.

Sweat-excretory model of GSR The process of conduction of electric current through the skin is determined by the electrical conductivity of liquids (sweat secretions and hydration of the upper layer), and quantitatively the electrical parameters of the skin are determined by the quantitative parameters of the secretion of liquids.

Sweating model of GSR Qualitative changes in the composition of fluid in the skin are not considered. When a person is activated under the influence of impulses in the nerve endings of the upper layers of the skin, the intensity of sweat secretion in the sweat glands increases.

Sweat model of GSR Rapid (phasic) changes in the GSR signal reflect an increase in electrocutaneous conductance and a decrease in electrocutaneous resistance. Slower tonic changes in the level of the GSR signal are determined by the intensity of sweating and the degree of hydration (saturation of the upper layers of the skin with liquid electrolytes).

Ionic model of GSR (Sukhodoev V.V.) In a normal functional state, a significant part of tissue ions is in an active (free) state, which ensures that the skin can perform its function of energy exchange between the human body and the external environment.

Ionic model of GSR (Sukhodoev V.V.) With increased activation (due to nerve impulses), the activity of electrolyte ions increases and the energy potential of cell membranes decreases. Ions on cell membranes move from a free to a bound state and increase the conductivity of the skin, i.e. an activation reaction in the form of phasic GSR is observed.

Ionic model of GSR With a decrease in the energy impact from the central nervous system the processes of transition of ions into a more stable bound state are automatically activated due to their grouping on cell membranes (part of the ion energy is transferred to the cells to intracellular processes associated with the accumulation of energy at the cellular level).

Three main types of background GSR (L.B. Ermolaeva-Tomina, 1965) Stable (in background GSR, spontaneous fluctuations are completely absent); Stable-labile (in the background GSR, individual spontaneous fluctuations are recorded); Labile (even in the absence of external stimuli, spontaneous fluctuations are continuously recorded).

Galvanic skin reactivity Galvanic skin reactivity is the ease with which reactions to exposure develop. According to the degree of reactivity, all people are divided into low reactive (reactions do not occur even to stimuli of significant intensity) and high reactive (any, even the most insignificant external influence causes intense GSR). Available intermediate types. Highly reactive people are active, excitable, anxious, self-centered, and have a highly developed imagination. Low reactive people are lethargic, calm, and prone to depression.

The rate of GSR decay and typological properties of the nervous system The rate of GSR decay upon repetition of the stimulus is slower in individuals with highly dynamic excitation; in individuals with highly dynamic inhibition, a rapid decay of GSR is observed as the stimulus is repeated.

Method for determining the strength of the nervous system (according to V.I. Rozhdestvenskaya, 1969; V.S. Merlin, E.I. Mastwilisker, 1971) Registration of evoked GSR for repeated (30) presentations of the stimulus. The reaction to the first five presentations is not taken into account, because is regarded as indicative. The average GSR amplitudes for the 3 second (from 6 to 8) and 3 last stimulus presentations are compared. An indicator of the strength-weakness of the nervous system is percentage logarithms of average amplitude. The higher the coefficient value, the higher the strength of the nervous system.

GSR amplitude values ​​In the normal state, the GSR amplitude is mV/cm; With increasing excitation, the GSR amplitude increases to 100 mV/cm.

GSR-BFB training Being a correlator of psycho-emotional state, GSR is widely used in the biofeedback circuit in the treatment of diseases of the central nervous system, neuroses, phobias, depressive states, various emotional disorders, and increasing mental stability in stressful conditions. By eliminating excessive autonomic activation in response to external factors, biofeedback - GSR training for practically healthy people can reduce the psychophysiological cost of activity and improve its quality, especially in situations of high responsibility, lack of time, information and funds, as well as in conditions of probable danger and interference .

RAG-BOS training Purpose of the procedure. Formation in the patient of a stereotype of inhibition of the autonomic activation reaction in response to the presentation of unexpected sound stimuli. Indications and contraindications. Recommended for patients with excessive autonomic activation in response to the presentation of an insignificant acoustic stimulus. They can be used at the final stage in a course of teaching relaxation skills under the influence of interfering stimuli. In addition, normalizing the rate of extinction of the indicative reaction is one of the auxiliary stages in the course of increasing mental stress resistance. This type of training is contraindicated in acute psychotic conditions, neurosis-like consequences of head trauma, neuroinfections and other organic brain lesions.

Application specifics During the procedure, the room must be maintained at a constant temperature of 20...24 C° and there should not be extraneous sounds. It is not recommended to start training earlier than two hours after a heavy meal. The hand with the electrodes rests freely on the armrest of the chair; active movements should be excluded, if possible. In some cases, with the same stimuli, a difference in the amplitudes of reactions on the right and left hands may be observed. In this case, the side with larger amplitude values ​​should be used.

Scenario of biofeedback training for RGC “Introductory” Idea of ​​the scenario. By controlling the dynamics of one’s own GSR during episodic presentation of unpleasant sound stimuli, the patient finds and consolidates a response skill that is not accompanied by bursts of GSR and, accordingly, excessive autonomic activation. Specifics of the scenario. As a model of stressful effects, acoustic signals of increased volume and subjectively unpleasant for the patient are used. The moments of their presentation are generated randomly using a signal generator.

Biofeedback training scenario for GSR “Introductory” Controlled parameters and removal configuration. The absolute value of GSR (M GSR) is used as a controlled parameter. GSR registration is carried out from the palmar surface of the distal phalanges of the index and middle fingers of one of the hands. Before applying the electrodes, the skin is treated with a 70% alcohol solution. There should be no abrasions or other skin damage on the finger in the area of ​​contact with the working part of the electrode. If they are present, you can use another finger or move the electrode to the middle phalanx of the same finger. The fastening of the electrodes should not be tight.

Description of the procedure “Increasing stress resistance” Purpose of the procedure. Used to master and consolidate skills in reducing the severity of vegetative manifestations and emotional tension when exposed to stress factors. Indications and contraindications. Recommended for functional training therapy of patients with neurosis with anxiety-phobic symptoms, improving mental adaptation, increasing a person’s mental resistance to various stress factors. It is also recommended for overcoming internal mental tension, feelings of vague anxiety and causeless fear. The procedure can be used by practically healthy people whose activities occur under conditions of increased responsibility, lack of time, and possible danger.

Description of the procedure “Increasing stress resistance” The procedures are contraindicated in acute psychotic conditions, neurosis-like consequences of head injury, neuroinfections and other organic brain lesions. It should be taken into account that, as with the use of any type of biofeedback, the effectiveness of biofeedback based on GSR is reduced in patients with intellectual and mnestic disorders. Therefore, in the presence of this severe pathology, it is necessary to consider the feasibility of prescribing the described method. Recommended for patients with excessive autonomic activation in response to the presentation of an insignificant acoustic stimulus.

Description of the procedure “Increasing stress resistance” Specifics of application. To provoke a state of anxious anticipation in the patient, electrocutaneous stimuli (ES), generated using an electrical stimulator, are used. Preliminary instruction, patient consent, and individual selection of electrical stimulation intensity are required. The felt inserts of the electrostimulator electrodes should be well moistened with tap water. As they dry, the stimulation intensity decreases, so if your workout lasts more than 30 minutes, use the Pause button and wet them further. It is not recommended to use more than 15 ES in one procedure.

Description of the procedure “Increasing stress resistance” They can be used at the final stage of a course of learning relaxation skills under the influence of interfering stimuli. In addition, normalizing the rate of extinction of the indicative reaction is one of the auxiliary stages in the course of increasing mental stress resistance.

Literature 1) Dementienko V.V., Dorokhov V.B., Koreneva L.G. and others. Hypothesis about the nature of electrodermal phenomena // Human Physiology T C) Ivonin A.A., Popova E.I., Shuvaev V.T. and others. Method of behavioral psychotherapy using biofeedback based on galvanic skin response (GSR-BFB) in the treatment of patients with neurotic phobic syndromes // Biofeedback, 2000, 1, pp) Fedotchev A. I. Adaptive biofeedback with feedback and control of the functional state of a person / Institute of Cell Biophysics RAS // Uspekhi Physiological Sciences T. 33. N 3. S

One of the leading indicators of the state of the central nervous system in assessing emotional tension is the skin reaction (SR). Currently, there are two types of CR: phasic and tonic. Phasic CR (from the word “phase” - variable value) is the response of the central nervous system to some short situational stimulus, which is called a reaction to novelty of information. But if you continuously say to the suspect: “You raped,” then after several repetitions the response will begin to decrease and will soon stop altogether.

A decrease in indicators may occur after the fourth or fifth presentation. This phenomenon is based on “getting used to” a significant signal. It is determined by the level of motivation in hiding information, the type of human nervous system, and its functional state.

A tonic skin reaction is a slow change in skin resistance or skin potential (tension) that characterizes a neuro-emotional state. If a person is unexpectedly placed in a stressful situation, then the tonic CR will be rebuilt within 2-3 minutes. Two to three minutes is the delay time of the tonic reaction to an emotional stimulus. The amount of skin resistance that was actually observed in stressful situation, varied from 300-600 kOhm to 1-0.1 kOhm. At the first stage of studying skin reactions, researchers differentiated techniques based on the method of measurement. If the voltage between two sections of biological tissue is recorded, it is called galvanic skin response (GSR) after the scientist L. Galvani, who first observed this phenomenon. This procedure is sometimes called electrodermography (from Greek word derma - skin).

A significant number of works, like ours, are devoted to the study of the skin reaction of CR in laboratory and production experiments (I.S. Condor, 1980, N.A. Leonov, 1980, A.A. Krauklis, A.A. Aldersons, 1982, etc. .), and abroad (Wang 1961, Codor 1963, Edelbery 1964, Hori 1982, etc.). The history of the discovery of this phenomenon dates back to the end of the nineteenth century, when in 1888 C. Feret in 1889 I.R. Tarkhanov was the first to establish a relationship between the level of skin resistance (skin potential) and the psychophysiological state of the body.

In his work presented at a meeting of the St. Petersburg Society of Psychiatrists and Neuropathologists, I.R. Tarkhanov reported that any irritation inflicted on a person, after some latent period, causes a strong change in the level of recorded indicators. Moreover, the irritations caused are not necessarily related to the skin itself. Even mental execution 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 his imagination. With the development of fatigue, the magnitude of the response decreases significantly. Subsequently, the discovery made by I.R. Tarkhanov was reflected in world literature as the “Tarkhanov phenomenon”, which consists in the fact that the electrical potential of the skin surface was measured using a sensitive galvanometer at various states the organism being studied. In parallel with Tarkhanov, almost at the same time, Feret revealed a similar dependence in changes in skin resistance. Scientists such as V.P. Gorev, (1943), S. Duret R. Duret, (1956) and others conducted a comparative assessment of two methods for measuring skin resistance and skin potential.

The subjects' CR and electrocutaneous resistance were simultaneously recorded under various sound, light, and pain stimuli. They found that the curve shapes are almost identical. Despite the fact that more than 100 years have passed since the first serious study of skin potential, the issue of the mechanism of the galvanic skin reflex remains quite controversial. So, in 1889 I.R. Tarkhanov came to the conclusion that skin potentials arise due to the removal of biocurrent from areas with different quantities sweat glands To implement his idea, I.R. Tarkhanov proposed a special technique for removing skin potential. They recommended the palmar and dorsal surfaces of the hand and the human forearm as points for applying electrodes. The mechanism of the emergence of skin potential, as I.R. believed, is based on Tarkhanov, there is a change in the intensity of sweat secretion under the influence of the central nervous system. Tarkhanov's theory about the origin of the CR was questioned in 1963 (Zyerina, Skoril, Saurek). Studying the speed of spread of CR, they found that in the upper extremities it was 154.9 cm/sec, and in the lower extremities it was 71.6 cm/sec. In connection with these data, the assumption that the occurrence of CD cannot be based on metabolic processes, especially the function of the sweat glands, is quite justified. Since their excretory processes are too inert compared to the speed of CR.

The independence of the origin of CR from the functional state of the sweat glands was demonstrated by the works of Wilcott (1957). By simultaneously examining sweating, skin electrical resistance, and skin potential from the palms of 35 subjects during oral math problem solving tests, Wilcott et al found that the change in electrical resistance occurred 1.1 sec earlier than sweating. It was found that the delay time of the CR in the same subject was almost constant. Despite a number of contradictory and even often mutually exclusive theories about the origin of constant potential, no one doubts the participation of the central nervous apparatus in this process. The skin reaction is closely related to both the general condition of the central nervous system and its various parts.

By recording the area of ​​the described CR curve from both hands, Raevskaya et al. (1985) revealed an asymmetry in the reaction. In a calm state, when the subject was presented with a series of photo flashes, the CR was more pronounced on the left hand, and when counting time intervals in the mind, the indicators on right hand. This is apparently due to the fact that in in this case The left hemisphere is predominantly activated. Studies conducted during the transition from wakefulness to sleep have shown that during the process of falling asleep, phasic GSR activity decreases, reaching a minimum during sleep.

An attempt was made to study the daily rhythms of electrocutaneous resistance in order to establish its periodicity. Thus, Pytenfranz, Hellbrugge, Niggeschmid (1956), studying the daily periodicity of 8 subjects, found that the rhythm of fluctuations of this resistance from 8 to 11 o’clock was significantly higher, and from 12-15 and 18-20 o’clock it was below the average level. The daily curves of electrocutaneous resistance of children, in general, are similar to the curves of adults, although they were shifted to the left by 1-2 hours (for children, the morning maximum is at 8 o’clock, for adults at 10 o’clock, the daytime minimum is at 12 and 14 o’clock, respectively). The maximum “flattening” of the curve and its 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 reliable indicator of the body to the novelty of the stimulus. CD arises only as a result of a discrepancy between the received information and the expected one, and is not the result of “irritation” in the usual sense of the word. (E.N. Sokolov, 1960, 1962).

The nature of CR is also significantly influenced by age and individual gender differences (E.N. Kutchak et al.). By studying changes in the resistance of human skin during its development, it was found that minimal numbers are observed in newborns, and, starting from one year, skin resistance gradually increases. In old age, a decrease in CR is observed, reaching a value not much greater in old age than in newborns.

Research by V.N. Myasishchev (1929, 1936) revealed a direct connection between the magnitude of the stimulus and the amplitude of the CR. At the same time, in the work of A.I. Zingerman (1967) showed an inverse relationship between the probability of a signal and the magnitude of the galvanic skin response. The lower the probability of its occurrence, the greater the response of the Kyrgyz Republic. A skin reaction accompanies all human mental processes, especially if they are obvious emotional coloring, being a total biological effect, the nature of which is determined by the functional state of a large number of organs and tissues of the body and allows, in some cases, a rather subtle analysis of human psychophysiological reactions (A.K. Podshibyakin, 1949, 1954; I.A. Vetokhin, L.P. Timofeeva , 1957). In 1967, Lakte established that CR can reflect the body’s preparation for the upcoming perception of information, taking into account the physiological characteristics of a person and the nature of motivations.

The study of CR at various degrees of tension revealed a direct dependence of the magnitude of the change in skin resistance on the magnitude of emotional tension. The galvanic skin response can be used not only as an indicator of a person’s emotional state, but also, under appropriate conditions, allows one to determine its value. A stimulus of greater social significance (subject to the same emotional stability of the organism) will correspond to a more pronounced manifestation of the skin reaction.

CR is based on neural mechanisms that ultimately reflect both the magnitude of the stimulus and the probability of its occurrence (entropy). The nature of the CR response is largely determined by the functional level of the regulatory system, whether a person is tired or alert, and the presence of pathology. Various methodological approaches were used to assess the informativeness of the CR. The delay time (Dorrow 1967), maximum amplitude (A.A. Krauklis, A.A. Aldersons, 1982), duration and area of ​​waves (P.V. Tarakanov, 1982) were studied. Each of the methods has the right to exist, although, in our opinion, measuring the area of ​​Raman waves should be considered the most informative indicator. Analyzing the results of studies by various authors on CR, we see that, in some cases, when a person is exposed to relatively identical sources of stress, researchers came to completely opposite results. To identify the reasons for the inconsistency of the results obtained, a special study was conducted (V. A. Varlamov, 1974). Two groups of subjects participated in the experiment: emotionally stable and emotionally unstable, reacting inadequately to stress. The tonic and phasic components of the CG were recorded against the background of a gradually increasing neuro-emotional load (segment a - m Fig. 2). It was found that the tonic component of CR changed unidirectionally with increasing emotional stress (skin resistance decreased). At the same time, phasic CR had a biphasic dependence on the magnitude of emotional stress (Fig. 2). At the first stage of the task, an increase in the frequency and amplitude of phasic CR oscillations was observed. Further, with the continued increase in emotional stress, a decrease in the amplitude of the CR was observed (point M). These studies once again confirmed the need to be attentive to the functional state of a person during the study, to strive to optimize his condition, otherwise the data of the polygraph examination will be significantly distorted

Rice. 2. Measuring the frequency and amplitude of the CR during smoothly increasing and gradually decreasing emotional stress:

a - background,
b - maximum response at the stage of increasing emotional stress,
c - minimal reaction at the moment of maximum stress,
d ~ maximum response at the stage of reducing emotional stress,
e - cessation of the action of the emotional stimulus,
M - maximum emotional stress

Analysis of data on the mechanism of occurrence and regulation of skin reactions and its informative signs showed that:
-tonic skin reaction is a reflection of deep processes of functional restructuring in the central nervous system;
- the magnitude of the “response” of the galvanic skin reflex is directly dependent on the novelty of the stimulus, typological features of higher nervous activity, the level of motivation of the subject and his functional state;
- dynamics of phasic CR indicators can be a criterion for the degree of emotional overstrain functional system person. If a further increase in emotional stress leads to a decrease in phasic CR, then this indicates a limit functionality subject;
- registration methods, measuring the dynamics of skin resistance, or skin potential, from the point of view of information content, do not differ;
- informative features of the KR curve are common to any periodic curves.

When analyzing the CR, it is necessary to take into account the characteristics of the mobility of the nervous system of people, taking into account regional and national characteristics. It is impossible to determine from the KR curve whether a representative of what nationality is being tested, a Georgian or a Chechen, but it is possible to determine that they are representatives of “southern” peoples, both temperamental, with a flexible nervous system. Indicators that can be used for subsequent analysis are presented in Fig. 3. These include the reaction delay time (segment a-b). From the moment the stimulating information is presented to the subject, the reaction delay time is normally 1.2-3 seconds. The length of the ascending curve (segment b-c) characterizes the power of activating excitation processes. The descending curve (segment c-d) is the intensity of activation of inhibitory processes. The time during which the reaction reached its maximum (1D) determines the mobility of excitation processes.

In almost all cases, when analyzing Raman curves, it is measured maximum height curve (h), reflecting the strength of the emotional response of the subject’s central nervous system to the presented stimulus. The area measured under the curve (S) is highly informative. It is an integral indicator that combines the amplitude (А) and the total duration of the curve t 1. The negative phase of the main curve (n) also carries information. The negative phase is the part of the curve that

Rice. 3. Indicators characterizing the KR curve:

A is the amplitude of the reaction,
B - time,
S - incentive,
a, b - reaction delay time,
b, c - length of the “ascending” curve,
c, d - length of the “descending” curve,
t, is the time during which the reaction reached its maximum,
tg is the time during which the reaction reached its initial state,
h is the amplitude of the curve,
S is the area under the curve,
D - the top of the negative phase of the curve,
h is the amplitude of the negative phase of the curve,
f, h - “damped” curves.

It is located below the zero line and characterizes the degree of inhibitory reactions of the central nervous system, designed to correct excitation reactions. The negative phase curve (vertex “D”) is analyzed according to the same indicators as the main one (amplitude duration, etc.), with the only difference being that it characterizes inhibitory processes. The greater the amplitude h in the negative phase curve, the more actively the system was activated, counteracting, that is, inhibiting the excitation processes after their manifestation. The state of excitation caused by the presented stimulus cannot be constant or endless.

The inclusion of inhibitory mechanisms has a protective function, since a long stay of the human body in a state of excitation is undesirable and has a detrimental effect on the system as a whole. If the inhibitory mechanism is very powerful, then the curve “overshoots” the zero level and goes into the “negative phase” (Fig. 4 - curve 1B). Thus, the more pronounced the “negative” phase in the KR curve is in the subject, the greater the suspect’s ability to control his condition in extreme conditions.

However, it should be remembered that exceptions are possible due to the individual characteristics of the subject or the counteraction technique he uses. The descending part of the curve is a reflection of the activation of inhibitory processes. The more powerful this process, the faster the excitation is compensated and the steeper the curve tends to the isoline (Fig. 4 - curve 1B). If the CR reaction is positive, i.e. the curve is located above the isoline, then its ascending part and amplitude are determined by excitation processes. Normally, the balance of excitatory-inhibitory processes is expressed by the ratio 1.0: 1.2. Inhibitory processes should slightly prevail over excitation processes, by about 5-10%. The presence of a powerful inhibitory process is of great importance for the normal functioning of the nervous system. However, the presence of consistency, balance, and interaction between the processes of excitation and inhibition also plays an important role in responding to stimulating information.

In the absence of balance and consistency, inhibition, once turned on, will affect the human body for a very long time, which can also lead to difficulties in interpreting the results obtained. This phenomenon can be seen in curve No. 2B (Fig. 4). The resulting excitation (vertex “A”) was compensated by inhibition (B), which did not “turn off” almost until the end of recording the reaction. In practice, opposite reactions also occur (curve 3). The curve from the peak "A", caused by increased excitation to the stimulus (N), very slowly

Rice. 4. Some types of CD shape in the background and after the stimulus:

N - stimulus,

A, B, C, D - the vertices of the curve,

Isoline.

returns to the original level. This phenomenon is possible if the response, inhibitory process turns on slowly, sluggishly, and inadequately to the strength of the excitation process. The lack of balance between activating and inhibitory processes can be seen in Fig. AL- After a standard response to a stimulus, the curve does not fade and does not return to the zero line. Several small bursts appear on it, lasting almost the entire measurement period. It should be borne in mind that the greater the consistency of the processes of excitation and inhibition, the less visible are the additional peaks on the curve.

The regulatory system in the body is designed in such a way that there is always a certain imbalance of corrective processes. This is due to the fact that commands from the “center” to turn on certain reactions arrive late, and, consequently, they are somewhat overregulated. In our example (curve 4) this phenomenon is clearly visible. After the increase in the excitation process, which led to the appearance of peak “A,” inhibitory reactions are activated. The curve decreases sharply, reaching the isoline. By the time the command arrives at the “center” that the process of bringing the excitation reaction to the original base level is completed, the opposite command will be received - to weaken the inhibitory processes.

Time will pass, the curve will “overshoot” the baseline ( points B, C, G). And the system that increases arousal will be “connected”, and the curve will go up, trying to reach the initial level. And again, due to the delay of commands, the isoline will “overshoot”, 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 magnitude of emotional stress and is determined by the general functional state of the subject. This explains the appearance of additional peaks on the curve or an increase in the amplitude of existing ones. In practice, one can encounter an increase in both the number of vertices and their amplitude, although this phenomenon is not necessary.

There may be cases when additional peaks of the curve are more clearly expressed in the background before testing (Fig. 4 - curve 5 peaks C and B). When testing begins, they sharply decrease or disappear completely. This is explained by waiting stress, which is based on a lack of information about the verification procedure. This type of reaction is observed in people for whom the absence (deficit) of information and its uncertainty cause greater emotional stress than the information itself (curve 5).

Fig.5 Various shapes CR reactions in response to the presented stimulus:
N-stimulus
A,B-curve vertices

Expectation stress can also manifest itself in the repeated appearance of “peaks” on the curve (curve 6B). This false signal, which does not carry information about the presented stimulus (question), is easily determined if it was preceded for a long time by a relatively flat section of the polygram. The specialist must remember that the “lag” in the appearance of the response to the question presented lies within 1.2-3 seconds from the moment the subject understands the information presented to him, if the recording of the results begins after the question asked. Therefore, the “key” word in the question should come at the end of the phrase. For example, you can construct the phrase: “Did you kill a woman and a child?” The reaction of the Kyrgyz Republic can be obtained after the words “killed”. IN in this example it is basic (key) in the formation of emotional tension. The same information could be presented to the subject in a different sequence: “Did you kill a woman and a child?” In this question, the keyword comes at the end of the phrase. The response to it will appear in 1.2-3 seconds. If the “response” reaction on the KR curve is observed after 4-6 seconds or more, then it is caused not by the presented stimulus, but by associative memories of events related to his past, including criminal ones. If the basic information contained in the presented question and the associative information is realized by the subject with short time delays, then the curve may have several peaks (Fig. 5-2 A, B). For example, this reaction may occur if citizen “M”, previously convicted of rape, when presented with a significant question, begins the usual reaction after 1.2-2 seconds. after the “key” word, and at that moment he will remember the place of imprisonment where, by coincidence, he miraculously managed to stay alive. This information is the stimulus that causes additional emotional stress. It is possible that these memories may be somewhat delayed in time. In this case, a second, rather powerful peak is observed (Fig. 5 - curve 3 B). In this example with citizen “M,” there may be cases when, after the “key” word, he first remembers the events in the zone (Fig. 5 - curve 4 A), and then the next crime he committed (4 B).

Galvanic skin response(GSR) is a bioelectric reaction recorded from the surface of the skin. Synonyms: psychogalvanic reflex, electrical activity of the skin (EAS). GSR is considered as a component of the orientation reflex, defensive, emotional and other reactions of the body associated with sympathetic innervation, mobilization of adaptation-trophic resources, etc., and is the result of the activity of the sweat glands. GSR can be recorded from any area of ​​the skin, but best of all - from the fingers, hands, and soles of the feet.

The widespread use of GSR for research and practical purposes was initiated by the French neurologist C. Feret, who discovered that when a weak current is passed through the forearm, changes occur in the electrical resistance of the skin (1888), and the Russian physiologist I. R. Tarkhanov (Tarkhnishvili, Tarkhan-Mouravi) , who discovered skin potential and its changes during internal experiences, as well as in response to sensory stimulation (1889). These discoveries formed the basis for two main methods for recording GSR - exosomatic (measurement of skin resistance) and endosomatic (measurement of the electrical potentials of the skin itself). Later it turned out that the methods of Feret and Tarkhanov give different results.

K. Jung and F. Peterson (1907) were among the first to show the connection between GSR and the degree of emotional experience. In the GSR, Jung saw an objective physiological “window” into unconscious processes. GSR is one of the most common indicators, which is explained by the ease of its registration and measurement. It is successfully used to monitor a person’s condition when performing different types activity (diagnosis of functional state), in studies of the emotional-volitional sphere and intellectual activity; is one of the indicators in lie detection. Quite interesting and varied facts were discovered: a more pronounced increase in GSR in response to funnier jokes (E. Linde); correspondence of GSR peaks to stressful film episodes (R. Lazarus et al.); a more significant increase in skin electrical conductivity during the emotion of fear than during the emotion of anger (E. Ex); an increase in GSR when perceiving obscene words (E. McGuinness), etc. All these facts indicate the high sensitivity of GSR indicators. At one time, the KGR saw something like a universal key to almost everyone psychological problems(here the “magic of objectivity” and the simplified idea that emotional states can be described using only one parameter, namely arousal, played a role), but this turned out to be another scientific utopia. The limited capabilities of GSR as a psychophysiological indicator are evidenced, in particular, by the data of G. Jones (1950) that, within certain limits, there is an inverse relationship between the value of GSR and arousal manifested in behavior. In addition, in studies on advertising effectiveness, it was found that GSR indicators during the perception of advertising are far from unambiguously related to behavioral reactions.

Recently, many psychophysiologists have opposed the very term “GSR” and replaced it with the more accurate “EAC” ( electrical activity of the skin), combining a number of indicators that vary depending on the nature of the stimulus and the internal state of the subject. EAC indicators include skin potential level (SPL, or SPL), skin potential reaction (SPR, or SPR), spontaneous skin potential reaction (SSPR, or SSPR), skin resistance level (USR, or SRL), skin resistance reaction (RSR , or SRR), skin conductance level (SPC, or SCL), etc. In this case, “level” means tonic activity (relatively long-term conditions), “response” means phasic activity (short, within a few seconds, responses to stimuli) and “spontaneous” - reactions that are difficult to associate with any stimulus. The level of tonic electrocutaneous resistance is used as an indicator of the functional state of the central nervous system. With. In a relaxed state, e.g. During sleep, skin resistance increases, and with a high level of activation it decreases. Phasic indicators react sharply to a state of tension, anxiety, and increased mental activity.