SU1560230A1 - Electrostimulator of nervous system - Google Patents

Abstract

The invention relates to medical technology, namely to electrostimulators of the nervous system. The purpose of the invention is to increase the effectiveness of inhibition of the nervous system by optimizing the frequency of stimulation. The device contains a master oscillator 1, standby multivibrator 2, amplifier 3, electrodes 4.5, first switch 6, first counter 7, second counter 8, digital-to-analog converter 9, integrator 10 with key 11, comparator 12, second switch 13, modulating generator 14 , a resistance sensor 15, a differentiator 16, a first trigger 17, a second trigger 18, a decoder 19 and a third switch 20. The device changes the stimulation frequency until the patient’s skin resistance becomes constant. 3 il.

Description

(21) 4364108 / 28-14

(22) 01/18/88

(46) 04.30.90. Bul Number 16

(71) Smolensk branch of the Moscow Energy Institute

(72) A. M. Kovalev, V.V. Round,

V. S. Gorkoy, V. A Zubov and M. A. Lapitsky

(53) 615.471 (088.8)

(56) USSR Author's Certificate No. 1123714, A 61 N 1/36, 1984.

(54) ELECTROSTIMULATOR OF THE NERVOUS SYSTEM

(57) The invention relates to medical technology, namely to electrostimulators of the nervous system. The purpose of the invention is to improve the efficiency of inhibition of the nervous system by optimizing the frequency of stimulation. The device contains a master oscillator 1, standby multivibrator 2, amplifier 3, electrodes 4, 5, first switch 6, first counter 7, second counter 8, D / A converter 9, integrator 10 key 11, comparator 12, second switch 13, modulating generator 14, resistance sensor 15, differentiator 16, first trigger 17, second trigger 18, decoder 19 and third switch 20 The device changes the stimulation frequency to until the skin resistance of the patient becomes permanent. 3 silt

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The invention relates to medicine, namely to electrostimulators of the nervous system.

The purpose of the invention is to increase the effectiveness of inhibition of the nervous system by optimizing the frequency of stimulation.

FIG. 1 shows a block diagram of the device; in fig. 2 - timing diagrams at the outputs of the device blocks; in fig. 3 - the form of stimulating pulses.

The device (Fig. 1) contains a master oscillator 1, standby multivibrator 2, amplifier 3, electrodes 4, 5, first switch 6, first counter 7, second counter 8, digital-to-analog converter 9, integrator 10 with key 11, comparator 12, second switch 13, the modulating generator 14, the resistance sensor 15, the differentiator 16, the first trigger 17, the second trigger 18, the decoder 19, and the third switch 20.

Three consecutive cycles can be distinguished in the operation of the device: the 1st cycle is the “coarse search for the optimal frequency, the 2nd cycle is the specification of its value, the 3rd cycle is the electrosign session itself.

The first stroke begins immediately after the apparatus is connected to the patient. The initial state of the device elements is as follows: the second counter 8 is reset, triggers 17, 18 are in the zero state, which corresponds to the upper position of the first 6 and second 13 switches and the inclusion of the second counter 8 in the summation mode.

The pulses of the master oscillator 1 are fed directly to the input of the second counter 8, the code N of which is converted by the digital-analog converter 9 to a proportional current signal that is the input to the integrator 10: lex-to Kg-N-Uo ", where Ke is the slope of the digital-analog converter 9 ; ivi is the reference stress. The output voltage of the integrator 10 begins to increase, changing according to the law Ui0 (t) Kio-t, where Kyu is the slope of the integrator 10; t is the current time. Comparator 12 compares the integrator output voltage with the reference. At the time of the comparison of the compared voltages, the waiting multivibrator 2 generates a short pulse for the duration of which the discharge switch 11 of the integrator closes, releasing the latter. Further, the integration and reset processes are repeated.

The pulses arriving at the control input of the third perelchatil 20 are connected for the duration of their action the electrode 5 to the output of the amplifier 3 (Fig. 3). The latter amplifies the sum of the output voltage of the low-frequency modulating oscillator 14 and the voltage of the reference source. Thus, the patient is affected by the amplitude-modulated sequence

pulses with a frequency and duration determined by the signal of the waiting multivibrator 2.

The period of the output pulses (ignoring their duration in relation to the specified period) is T2 j7 - j --JT, therefore their frequency, Km-N is proportional to the current code of the second counter 8. Changing this code ensures a linear increase in the frequency of the pulses at this stage.

A resistance sensor 15 registers changes in the patient's skin resistance, which objectively reflects the excitation and inhibition processes. Thus, with the development of the patient inhibition process, an increase in skin resistance occurs. As clinical studies show, as the frequency increases, skin resistance first increases and then slightly increases as the comfort frequency gets closer (Fig. 2). The derivative of the galvanic skin reaction at this stage is compared with the bias signal, which is set by the upper resistor of the differentiator 16. When the latter are equal, the output voltage of the differentiator 16 jumps (whose amplifier operates in the saturation mode), which causes a change in the state of the first trigger 17. Signal at the output of the decoder 19, this changes and leads to switching the second switch 13 to the "lower position, the first switch 6 to the middle position, and the second counter 8 to the subtraction mode . The described switching correspond to the beginning, the second cycle of the device.

In other words, the frequency of the current impulses acting on the patient increases linearly until the change in skin resistance becomes negligible.

As the practice of clinical studies shows, the presence of a delay in the patient's response leads to the fact that the "comfortable pulse frequency, determined at the first stage, is overestimated, therefore, at the second stage its refinement is made. In this case, the pulses of the master oscillator 1 are fed to the input of the second counter 8 through the first counter 7, operating in the frequency divider mode. When this occurs, a decrease in the output code of the counter 8 and the frequency of the stimulating pulses. As we approach the actual value of the comfort frequency, a further increase in skin resistance occurs. The magnitude of the derivative of its change is compared in the differentiator 16 with a smaller value bias signal and, if they are equal, the voltage drop is generated at the output of the differentiator 16 (Fig. 2), which leads to a change in the state of the flip-flops 17, 18. The first switch 6 switches to " lower position. The arrival of pulses at the input of the second counter 8 stops and the frequency of the stimulation is determined by the unchanged code of the second counter 8 and remains constant throughout the third cycle of the session.

The described two-stage search of the comfortable frequency, as the practice of using the proposed apparatus has shown, provides a fairly quick determination due to the relatively high rate of increase in the frequency in the first cycle and the maximum braking for the patient due to slow refinement in the second cycle. The low speed of the refinement process completely excludes the effect of the above-mentioned galvanic skin reaction delay.

Thus, the proposed device provides an automatic search for a comfortable frequency corresponding to the maximum inhibition of a particular patient, by organizing biotechnical feedback, which ensures an increase in the efficiency of the therapeutic action of the device for electrosync. The use of low-frequency amplitude modulation of the pulses affecting the patient also contributes to this.

Claims (1)

Invention Formula An electrostimulator of the nervous system containing a differentiator, a decoder. the first trigger, whose input is connected to the output of the differentiator, and the outputs are connected to the same inputs of the decoder, the first and second switches, one inputs of which are connected to the first and second outputs of the decoder, the master oscillator, the modulating oscillator, the amplifier, the third switch and electrodes, that, in order to increase the efficiency of the process of inhibition of the nervous system by optimizing the frequency of stimulation, it contains a resistance sensor connected to one input of the differentiator, a second trigger, an input to The first is connected to the output of the first trigger, and the output is connected to other inputs of the decoder, the first counter, whose input is connected to the output of the master oscillator, the second counter connected in series, the digital-to-analog converter, the integrator, the comparator and the waiting multivibrator, the output of which is connected to another integrator input and one input of the third switch, the output of which is connected to the electrode, and the other inputs are connected to the amplifier output and zero potential bus, the other inputs of the first switch are connected to the outputs specifying first generator of the first counter with zero potential bus and its output connected to one input of the second counter, another input of which is connected to the third output of the decoder, the outputs of the second switch connected to the other inputs of the differentiator, and a modulating generator output is connected to the input of the amplifier. FIG. 2 t I