RU2266043C2 - Automatic device for recording and analyzing evoked bioelectrical brain activity of testee - Google Patents

Abstract

FIELD: medical engineering.

SUBSTANCE: device has means for acting upon object under study, means for recording responses having transducers connected to computer via signal input/output unit, photorecorder unit having programmed control mechanism and frame marker unit having in series connected control desk, frame marker, superposed responses photorecorder, programming unit and switchboard connected to control desk, means for acting upon object, means for recording responses and computer. Photorecorder programming unit has cam mechanism, the switchboard has relay circuits, the frame marker unit has means for recording treatment protocol and means for recording current events being tape drive with transparent tape coupled with tape drive with exposed film. The means for recording responses have magnetic tape recorder connected to control desk and transducers via switchboard. Tape recorder signal input is connected to microphone for recording vocal data describing current experiment condition and testee data.

EFFECT: enhanced effectiveness in recording biopotentials and creating feedback links among testees; wide range of functional applications.

2 cl, 6 dwg

Description

The invention relates to physiology and experimental medicine.

When developing automated systems for collecting and analyzing physiological information, the capabilities of powerful personal computers with a large amount of RAM and disk memory are widely used. Automated systems for collecting physiological information are known (Pyatigorsky et al., 1985; Kulachev, Kaplan 1994; Panteleev et al., 1996 - a prototype and others), consisting of interconnected computers, means of influencing the object, and means of recording response.

The disadvantages of these systems are:

1. The inability to change current impacts during exposure. This especially applies to the formation of biological feedback, which requires combining high standardization (repeatability) of testing conditions with the need to make emergency changes to the conditions manually, depending on the current results of the experiment, the state of the test object (test, student, patient) and the required change in registration parameters. For example, when working with experimental animals, the researcher experiences the greatest difficulties, because, unlike human studies, he is deprived of the possibility of carrying out a verbal installation that ensures the standardization of evoked potentials and minimizes artifacts when biopotentials are introduced (EEG, RAG, pupil reactions, etc.) into a computer in on line mode. The ability to continuously monitor the information received by the operator, its indication, selective analysis, as well as reliable registration and storage of data not only in digital, but also in the native (analog) form, which allows for the assessment and correction of results, is important in these conditions. Solving this problem using standard computer systems for collecting and analyzing biopotentials is problematic.

2. When using the above computer systems for collecting information, there is an acute shortage of visual control, marking and selective analysis of individual biopotentials. With computer averaging of biopotentials, individual VP cannot be distinguished in superposed responses. Machine averaging of VP forms over series suppresses individual features of VPs in a series; therefore, according to a number of researchers, monitoring is not possible with a wide range of VP forms. In addition, many EEG phenomena (peak waves, spikes, paroxysmal discharges, sleep spindles, etc.) are practically not amenable to direct computer analysis, which complicates machine selection and statistical collection of the tested biopotentials, as well as interpretation of the results obtained.

3. When using standard computer systems for collecting information, there is also an acute shortage of visual monitoring, marking and selective analysis of biopotentials, as well as the absence of reliable duplicate hardware and software tools that ensure the preservation of data and the continuation of the planned research in the event of various emergency situations: program errors, failures disk memory, “freezing” of the operating system used or hardware malfunctions of the computer and input device / you water signals.

4. In a neurophysiological experiment, labeling of recorded biopotentials is important. Known methods of marking allow you to apply only digital tags that define only the serial number of the recorded potentials and do not provide the necessary information about the conditions for recording responses, the functional state of the object of study and the current experimental effects.

For the closest prototype, the device “Automated electrophysiological unit for the study of motor function of the gastrointestinal tract in rats” (authors Panteleev SS, Chikhman VN, Molodtsov VO), described in the Physiological Journal named after I.M.Sechenova, 1996, v.2, No. 4, p.135-140, consisting of means for influencing the object, means for registering responses associated with computers, having the above-described disadvantages.

The purpose of the invention is to expand the scope of use of the device and increase the reliability of the results obtained, increase the accuracy of identification, labeling and analysis of the induced bioelectric activity, provide the ability to change the current effects and their use in the formation of biological feedback in subjects.

The essence of the invention lies in the fact that the automated device for recording and analyzing the induced bioelectrical activity of the test brain, containing means for influencing the object of study, means for recording responses, including sensors connected through a signal input-output device with a computer, is equipped with a photorecorder unit with control software a mechanism and a frame marker performed on the control panel in series, a frame marker, and a supervisor answers, the programming device and the switch associated with the control panel, means of influencing the object, means of recording responses and computers, moreover, the programming device of the photoregrator is made on the cam mechanism, the switch is made on relay circuits, and the frame marker is equipped with means for recording the protocol of actions and means for recording current information, made in the form of a tape drive with a transparent tape, paired with a tape drive of the exposed Lenka.

2. The invention also lies in the fact that the means for recording responses is provided with a tape recorder connected through a switch with a control panel and sensors, while the signal input of the tape recorder is connected to a microphone for voice recording of information about the current conditions of the experiment and recording information from the subject. The proposed device in the form of a block diagram is shown in figure 1, where

1 - control panel

2 - marking device

3 - photo recorder superposed signals

4 - programming mechanism

5 - switch

6 - photorecorder unit

7 - block interaction with the object of study

8 - a computer, for example, a Pentium computer IBM PC AT

9 - device input / output signals

10 - object of study or training

11 - operator

12 - stimulants

13 - sensors

14 - registrars

15 - tape player

16 - amplifiers

Figure 2 shows an example implementation of the proposed device, where

17 - electric motor

18 - main time lapse

19 - position cam

20 - position cam

21 - position cam

22 - position cam

23 - contact switch

24 - contact switch

25 - contact switch

26 - contact switch

27 - start relay

28 - executive relay

29 - executive relay

30 - executive relay

31 - starter button

32 - photojournal (VF)

33 - exposed film

34 - additional time lapse

35 - receiving coil

36 - feed coil

37 - winding pulley

38 - support panel

39 - flash (photo-flash lamp)

40 - insulating block electrical stimulator

41 - insulating block of the electrical stimulator

42 - oscilloscope

43 - frequency modulator

44 - microphone

45 - recounter

46 - multivibrator waiting

47 - sync contact photopulse lamp 39

48 - standard FOROR photo recorder

49 - socket "sync" of the DVR 48

50 - speaker for audio feedback

51 - analog to digital converter

52 - digital-to-analog converter

53 - capacitor for pulse relay operation

54 - lamp-indicator of readiness of the device to work

55 - infrared pupilometer

56 - button start fixed mode without magnetic recording

57 - program lock switch

58 - magnetic record lock toggle switch

59 - program lock toggle switch

60 - toggle switch multiplying the number of tested stimuli

61 - photocamera lock switch

Figure 3 shows the timing diagrams of the nodes included in the device, where

X axis - plot of the pulse sequence during operation of the device;

Y axis - the operation order of the nodes included in the device.

Figure 4 shows the block diagram of the device adopted for the closest prototype.

Figure 5 presents a photomarking scheme of recorded biopotentials, where

32 - photojournal (transparent film with the applied protocol of experience);

33 - exposed film. The arrows indicate the direction of motion of the films during registration and labeling of potentials.

Figure 6 presents a fragment of the recording of recorded biopotentials with a fixed protocol of experience.

Figure 1 shows a block diagram of the proposed device containing a control panel 1 connected through a marker 2, a supervisor signals photographic recorder 3, a programming mechanism 4 and a switch 5, which are part of the photographic recorder unit 6, the interaction unit 7 with the object of study and computer 8 connected through the device 9 input / output signals with block 7 interaction with the object of study and the object of study 10.

Block 7 of interaction with the object of study 10 contains both means of influencing the object, which include stimulants 12, a tape recorder 15, and means of recording responses, which include a tape recorder that combines the functions of a means of influence and means of recording responses, sensors 13, recorders 14 .

The device provides for the possibility of changing current impacts by both the operator and the object of study (training), and the possibility of their interaction during the impact.

Figure 2 shows a diagram of an implementation of the proposed device, where the photorecorder unit 6 consists of a superposed responses photorecorder 3, equipped with an electric motor 17, which is connected via a gearbox to the tape drive mechanism 18 and to the cam programming mechanism 4, consisting of positional cams 19, 20, 21 , 22, the pushers of which abut against contact switches 23, 24, 25, 26 spring-loaded to them; starting relay 27; executive relays 28, 29, 30; engine start button 31; a marker, consisting of a transparent photographic tape with a marked recording - photojournal 32, which is located perpendicular to the exposed film 33, in contact with the photosensitive layer of the latter, and passes through an additional film channel and the tape mechanism of the photojournal. The latter contains an additional time lag 34 mounted on the camshaft of the gearbox, receiving 35 and feeding 36 coils and the winding pulley 37, as well as a support panel 38 for emergency application of information to the frames of the photojournal tape intended for this purpose. The flash 39 is mounted in the window opening of the photorecorder tube and is designed to expose the marking recording. The unit of interaction with the object of study consists of a 2-channel electrical stimulator 12; insulating blocks 40 and 41 in the output circuits of the electrical stimulator; Oscilloscope 42; amplifier biopotential 16; frequency modulator 43; microphone 44; recounting device 45; multivibrator 46; Photorecorder of superposed responses 3; flash units 39 in the form of a standard flash lamp; sync contact 47 of the photopulse lamp 39; photorecorder FOR production Institute of Physiology. A.A. Bogomolets, Kiev 48; Synchro sockets 49 of the DVR 48 (terminals of a normally open contact pair of a relay operating synchronously with the shutter of the DVR); tape recorder 15; speaker for audible feedback 50; a signal input / output device 9, including an analog-to-digital converter 51; digital to analog converter 52; Computer 8 (personal IBM PC AT computer); infrared pupilometer 55 for recording pupil reactions, a capacitor 53 for pulse relay operation. The composition of the control panel 1 includes: button 31 engine start; button 56 start fixed mode without magnetic recording; toggle switch 57 fixing the program; magnetic switch lock switch 58; toggle switch 59 lock the program; a toggle switch 60 multiplying the number of tested stimuli; toggle switch 61 lock the photorecorder; lamp indicator 54 readiness of the device to work.

The operation of the device is shown in FIGS. 2, 3, 5, 6. The device operates in pair testing mode, which is usually used for electrophysiological studies related to the study of the stimulation effect of various brain structures, the formation of behavioral reactions with combined irritation of various analyzers, and the formation of feedback with sensory stimulation of the subject. The work of the programming mechanism of the device is based on the automatic construction of removable control circuits by sequential formation of temporary logical connections, their preparatory and executive elements. In this case, the control circuit is interrupted by feedback or operate in a pulsed mode. The formation of the preparatory elements of the circuit is carried out by a group of positional cams 19-22 with contact switches 23-26, as well as toggle switches 57-61 of the control panel, and actuators - relay group 27-30. The registration program consists of the following acts: control, test control and labeling. Each of them is started manually using the button 31 or automatically by a pulse generated from the output of the digital-to-analog converter 52 of the computer. With an automatic start at the marking stage, it is possible to carry out complex testing operations, give brief instructions, evaluate and adjust the functional state of the test person, change the parameters of the lead and registration conditions.

Figure 2 shows the position of the cams 21, 22 preceding the test control mode. The normalized operation of the installation is carried out when the tumblers 57-59 are turned on, and 60, 61 are in the initial position (see Fig. 3. a graphic illustration of the automatic operation of the installation).

When you press the start button 31, the relay 27 is activated, self-locking contact P1 / 1. In the process of holding the button with the help of contact P1 / 2, the power circuit of the motor 17 is closed, which, by rotating the cam 19, with the contacts of its limit switch 23 becomes "self-locking" by power. The P1 / 3 group starts the tape drive mechanism of the tape recorder, and P1 / 4 connects its signal input to the output of the frequency modulator 43; group P1 / 5 prepares the start-up circuit of the FOROR 48 photographic recorder. When the engine 17 is rotated, the exposed film of the super-response 3 photographic recorder is drawn and the photo-logging film 32 is drawn; the capacitor 53 is charged through the power supply through the contacts 23; the contact switch 26 under the influence of the cam 22 enters a new state 2, disconnecting the start circuit of the relay 27 and preparing the output circuit of the first channel of the electric stimulator 12 to the object of study. The formation of frames ends as a result of the cam 19 turning off the motor power through the circuit of the contact switch 23. In this case, the reconstructed circuit through the other contact of the contact switch 23 discharges the capacitor 53 to the relay coil 28, as a result of which the group P2 / 1 is pulsed and, together with The "holding" circuit group P1 / 5 and the contact switch 26 includes a shutter, and with it the tape drive mechanism of the photorecorder 48. P2 / 2 and P2 / 3 are idle. At the end of the shutter release, the own sync contact of the photorecorder 48 is closed, forming the power circuit of the relay 29, after which the shutter is self-locking using contacts P3 / 1; the output of the first channel of the electric stimulator 12 is connected using the P3 / 3 groups, the limit switch 26, and the P3 / 2 contacts to the object of study, as a result of which sending test stimuli in the test control mode and synchronous registration of photo-superposed packets of evoked bioelectric responses (BO) on the photorecorder of superposed answers 3 and single VOs on the photorecorder 48 and the tape recorder 15 in an appropriate way, as well as digitizing the biopotentials and entering them into computer 8 using an analog-to-digital conversion Atelier 51. The photo-indication of VO is carried out on the screens of oscilloscopes 42 and a computer display. After passing a series of pulses from the output of the second channel of the electric stimulator 12 (the number of pulses multiple of 10 is set by turning on the toggle switch 59), relay 30 is activated, interrupting the power supply circuits of relays 29 and 27, as a result of which the involved elements of the Executive groups of the relay switch go into the initial state, interrupting the process stimulation and registration of HE.

The following is an act of the program that implements the labeling of information (figure 2, 3, 5, 6).

To initiate it in the “II” position of the cams 20-22, press the start button 31. By means of the corresponding contacts of the button, the tape drive mechanism of the tape recorder 15 is turned on. In this case, the signal input, thanks to the initial position of the P1 / 4 groups, is connected to the microphone 44. While holding the button, we record sound by voice information about the current conditions of the experiment or the text of the photojournal 32 stamp and the number of the next FOR input, which fits into the marking frame of the photojournal 32 during the planned (protocol) experiment. At the same time, the capacitor 53 is charged through the corresponding contacts of the contact switch 23 and the button 31. After sound recording, we release the button 31, as a result of which the stretching of the magnetic film is stopped, and the capacitor 53 is pulsed to the relay coil 28, which is pulsed. A chain through the contact groups P1 / 2, the contact switch 24 and the contacts P2 / 3 starts the engine 31 of the superposed responses 3 photorecorder 3, is blocked by the power supply using the contact switch groups 23, and the next frame of the exposed film 33 of the photorecorder 3 is formed, as well as combined with him brand photojournal 32 (Fig.5, 6). At the same time, the cams 20-22 bring their contact switches to new states, as a result of which the group of contact switch 24 switches off the preparatory connection of the motor power supply via the start circuit, by changing the position of the group of contact switch 25, the start circuit of the photopulse lamp 39 is prepared, and in connection with the transition of the group of contact switch 26, a preparatory connection is formed for starting the relay 27. After the operation of the group of contact switch 23, as a result of the transition of the cam 19 to the symmetrical state, the motor 17 stops, and the relay 28, discharging the capacitor 53 to its winding, is pulsed. In this case, using the P2 / 2 group, the photopulse lamp 39 is activated, exposing the photojournal frame to the photographic film of the photorecorder of superposed responses 3.

The next, 3rd act of the program provides for the registration of HE in the "control" mode. Figure 2 shows the corresponding operating position of the software cams 20-22, in which they move from position II. The transition to this position is also initiated by pressing the button 31, and the subsequent operation of the actuating elements is similar to the process of implementing the "test control" mode (discussed above) with the difference that the preparatory connection of the output of the first channel of the electric stimulator 12 through the contact group of the switch 26 is not formed , in connection with which the implementation of the "control" mode is expected.

The inclusion of the preferred registration modes (FOR 48 photorecorder, tape recorder, computer), as well as re-exposure of information or idle registrars is carried out by manipulating the tumblers 57-61 and buttons 31, 56 of the control panel. Further control is carried out automatically or cyclically by successively pressing the start button 31. The experiment program can be easily changed and / or supplemented by changing the position of the software cams on the motor shaft, as well as by connecting backup cams 20 with contact switches 24, which can be used for automatic inclusion in accordance with the requirements of the experiment of additional instruments and devices (photo-, phono-, mechanical stimulator, microinjector drive, etc.). It should be noted that a full-fledged electrophysiological experiment can be ensured during operation as part of the installation of one photorecorder of superposed responses with a software mechanism and a marker (computer, tape recorder and photorecorder 48 are turned off). This mode of operation of the installation is most convenient when organizing search (pilot) experiments on experimental animals, associated with the need to use a large number of samples, repeated changes during the experience of localization of the electrodes and stimulation parameters, as well as strengthening control over the functional state of the object of study, accompanied by viewing long sequences diverted evoked biopotentials. The engine of the super-response answers photorecorder 3, which pulls out the exposed tape and photojournal, can be turned off if necessary, in this case the test stimuli are also launched using the start button 31.

Thus, the introduction of a semi-automatic operation mode of an electrophysiological installation, which provides for the transfer of part of the functions associated with programming an experiment, controlling testing, converting and recording equipment, from a computer to a specialized electromechanical device - a switch made on relay circuits and controlled by an operator, optimally organizes a human-machine interface in a system of controlled electrophysiological experiment using persons ceiling elements VM computer.

The use of a designed photo recorder with a control program mechanism and a special marker in the setup allows us to facilitate (optimize) the work of the researcher at almost all stages of the electrophysiological experiment: 1) during the preparation and planning of the experiment (input of a photo journal / photo protocol of the planned experiment, installation of a cam mechanism for software connection necessary instruments and devices); 2) when performing research (monitoring of single and superposed EPs, selection of biopotentials for their photos, magnetic and machine recordings); 3) when editing and analyzing the recorded information (based on the full database of the experiment, synchronously recorded on a standard photorecorder 48, photorecorder superposed answers 3, tape recorder and computer hard drive).

It should also be noted that the use of the setup in sessions with the formation of feedback allows the subjects to independently launch the process of sensory stimulation and registration of the tested electrographic parameters (EEG, VP, RAG, pupil reactions) by remote pressing the start button 31. This makes it possible to free the subjects from the need for contact with the monitor screen, computer keyboard and additional instructions of the experimenter during the training session, which allows you to create a test favorable procedural conditions (turn off extraneous sensory stimuli, lie down on the couch, close your eyes, etc.), which are necessary for controlling and correcting the subject's functional state. At the same time, optimal conditions for muscle relaxation are provided, which are necessary for the artifactless abduction of the tested electrographic reactions. In experimental animals, the conditions for artifact-free biopotential diversion are provided using the atraumatic head holder developed by us [Albertin 1989], which allows electrophysiological studies with rigid fixation of the animal’s head without the use of narcotic substances and muscle relaxants.

DEVICE ADVANTAGES

1. The device allows you to create optimal conditions for recording biopotentials, to minimize the effect of artifacts when entering data into a computer and their subsequent machine processing by introducing a new node - a photographic recorder with a control software mechanism and a marker connected to a computer, a control panel, means of influencing the object and means of recording responses.

2. An automated device for recording and analyzing the bioelectrical activity of the test brain provides the ability to change the current effects when recording potentials, marking them and forming feedback from the subjects. This advantage is achieved through the introduction of a new unit - a photorecorder with a control software mechanism and a marker associated with a computer, means of influencing the object and means of recording response.

3. The device provides reliable registration and preservation of biopotentials (EEG, VP, RAG) not only in digital, but also in native (analog) form, allowing assessment and correction of experimental results. The device also provides data storage and the continuation of the planned experiment in the event of various emergency situations: software errors, disk memory failures, “freezing” of the operating system used or hardware malfunctions of the computer and the signal input / output device. This advantage is achieved through the use of a photorecorder unit with a software mechanism and a marker.

4 The device allows you to automate the marking process with the possibility of emergency input of information into the marking frame, and also frees the experimenter from the need for a protocol in the experiment. This advantage is achieved due to the fact that marking is carried out in the form of a concise recording of specific values fixed on a separate tape - a photojournal (photographic protocol) entered into the plane of the frame window of the photorecorder, as well as a significant increase in the marking field compared to the frame of standard photorecorders.

5. The device allows you to automate the control of the photorecorder, work out the supply of testing stimuli and connect external devices, as well as automate the operation of the electrophysiological installation by switching its electrical circuits. This advantage is achieved due to the automatic construction of removable control circuits by sequential formation of temporary logical connections, their preparatory and actuating elements, while the control circuits are interrupted by feedback or operate in a pulsed mode, the formation of preparatory circuit elements is carried out by a group of positional cam mechanisms of the photorecorder unit, and actuators - relay group.

6. The device allows the use of simple (inexpensive) ADC / DAC controllers for digitizing and inputting recorded biopotentials into the computer connected to the serial or parallel ports of the computer, to control the external feedback signal, and also greatly simplify the writing of control and data processing programs. This advantage is achieved by introducing a semi-automatic mode of operation of the electrophysiological installation, which provides for the transfer of some of the functions associated with the programming of research, control of testing, converting and recording equipment from a computer to a specialized electromechanical device - a switch made on relay circuits and controlled by an operator.

7. The device allows you to free the subjects from the need to contact the monitor screen, computer keyboard and additional instructions of the experimenter during the training session and, thus, create favorable conditions for the test person in the sessions with feedback formation (turn off extraneous sensory stimuli, lie down on the couch, close your eyes etc.) necessary for the control and correction of the subjects of their functional state. This advantage is achieved by providing the subject with the opportunity to independently launch the sensory stimulation process and registering the test electrographic parameters (EEG, VP, RAG, pupil reactions) by remote pressing the start button after the subject evaluates his functional state.

SOURCES OF INFORMATION

1. Albertin S.V. A device for immobilizing the head of an animal. Auth. testimonial. SU 1528473 A1, Bull. Invent., 1989, No. 46.

2. Kulachev AP, Kaplan A.Ya, Computer analysis systems for bioelectric signals. PC World, 1994, No. 8, p. 95.

3. Panteleev S. S., Chikhman V. I., Molodtsov V. O. Automated electrophysiological device for the study of motor function of the gastrointestinal tract in rats. Fiziol. Journal of them. I.M.Sechenova. 1996, vol. 82, No. 4, pp. 135-140 (prototype).

4. Pyatigorsky B.Ya., Zaitman G.A., Cherkassky V.A., Chinarov V.A. Automated electrophysiological experiment. Kiev "Naukova Dumka", 1985, p.190.

5. Khilko I.S. (Ed.) Oscillogram photographic recorder biological FOR-2. Description and passport FOR2-00.00.000PS, Kiev, 1986.

Claims (2)

1. An automated device for recording and analyzing the bioelectrical activity of the test brain, containing means for influencing the object of study, means for recording responses, including sensors connected through a signal input-output device with a computer, characterized in that it is equipped with a photorecorder unit with control software a mechanism and a frame marker performed on a series-connected control panel, a frame marker, a photo recorder of superposed responses, prog an ammonia device and a switch connected with the control panel, means of influencing the object, means of recording response responses and computers, the programming device of the photorecorder being made on a cam mechanism, the switch being made on relay circuits, and the frame marker equipped with means for recording the protocol of actions and means for recording current information, made in the form of a tape drive with a transparent tape, paired with a tape drive of the exposed film. 2. The automated device according to claim 1, characterized in that the means for recording responses is provided with a tape recorder connected through a switch with a control panel and sensors, while the signal input of the tape recorder is connected to a microphone for voice recording of information about the current conditions of the experiment and recording information from the subject .

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