RU2136211C1 - Method for diagnosis of person's functional state - Google Patents

Abstract

FIELD: medicine, in particular, diagnosis of person's functional state for determination of his general working capacity. SUBSTANCE: the new test of estimation consists in the following. 4 figures from 0 to 9 are produced simultaneously to the person under test. The time of production is preset within 0.5 s to 1 s, and the time interval after which the figures are produced again lasts within 1 to 5 s. The preset parameters are constant during the whole experiment. Then, the number of calculated productions of the given figure by the person under test is compared with the actual number of productions, and the working capacity is determined according to the value of the error. EFFECT: simplified conditions of experiment at an enhanced accuracy of calculation of errors. 1 dwg, 2 ex

Description

 The invention relates to medicine, namely to physiology of work, and is intended to assess the functional state of a person.

 A known method of determining human fatigue, in which the subject is repeatedly presented with stimuli at a constant time interval and the latent periods of a simple sensorimotor reaction are measured. The time trend of latent periods and the time series of residuals are calculated through the difference in latent periods and trend. Then a spectral analysis of the time series of the residues is carried out, at least three frequency regions are isolated in the frequency spectrum of the residues. At the time of determining fatigue, the power spectral density in the frequency domains is compared with the corresponding values during the period of the normal functional state and, if there are significant differences, fatigue is determined (1). This method is complicated and time-consuming in practical research, requires the availability of computer technology.

 Closest to the proposed one is a method for determining visual fatigue, which consists in the fact that the subject controls the rows of numbers moving in front of him on the screen and responds to a given number by pressing the counter button (2). To project the numbers on the screen, the DP-4 overhead projector was used, which provided motion of the film at a speed of 1 frame in 4.8 s. Previously, 64 frames of rows of numbers were shot. Each row contained 4 random digits determined using a random number generator. The subject was at a distance of 2.5 m from the screen, while the angular size of the numbers was 13 degrees. The ends of the film in the slide projector were glued together, which achieved its annular, continuous projection on the screen. The number of errors noticed by the operator was used to judge the performance of the subjects, the dynamics of fatigue in the process of purposeful activity. This load required increased attention from the subjects, a high speed of visual-motor reaction, and the distinctive ability of the eyes. The nature of the load simulated the production activities of a large number of professions in the textile and printing industries, was comparable to the visual load of vehicle drivers. It should be noted that in this method, the error count was not accurate. The film made a full revolution in about five minutes; in three hours of the film’s revolutions in the projector, the inaccuracy in calculating the number of presentations could not be excluded. This led to an error in determining the degree of fatigue. In addition, for 35 revolutions, i.e. for 35 repetitions of the situation within three hours, the subject could remember the order of presentation of the numbers, which did not change, for example, due to individual microdefects of the frame, the place of gluing the film, etc. Finally, this method of determining fatigue required the presence of a darkened room, its specific dimensions (at least 4.5 m in length), the presence of a movie screen, a film projector, a supply of film, because it wore out pretty quickly, a supply of lamps for the projector, etc. To change the speed of movement of the figures, it was necessary to redo the gearbox of the film projector.

 To simplify the conditions of the experiment, to increase the accuracy of calculating the number of errors in the method, which includes monitoring a number of digits that are presented simultaneously at a constant interval of 1-5 s, with a constant presentation time throughout the experiment of 0.5 - 1 s, determine the specified digit from 0 to 9, the presentations determined by the test subject are compared with the actual number of presentations of the given figure, and the working capacity of the test subject is determined by the number of errors.

 In the proposed method, the sequence of presenting the numbers is determined by the random number generator, it cannot be predicted, it is not repeated. An error has been eliminated in calculating the number of presentations of each digit, since the electronic pulse counter is working. The dimensions of the room are not regulated, additional dimming devices are not required. The speed of the change of numbers and the duration of their presentation is regulated by turning the knobs of the corresponding resistors.

 The drawing shows a block diagram of a device that implements this method.

 The device contains generators 1-5 electrical pulses made on the logical elements "NAND" chips of the K155 series (To help the radio amateur: collection, issue 76.- M: DOSAAF, 1982, p. 49). The frequency of operation of the generators, respectively, 110 kHz, 80 kHz, 20 kHz, 8 kHz and 0.5 Hz. The pulse width of 1.5 ms. The outputs of the generator 5 are connected to the inputs of the generators 1-4. The outputs of the generators 1-4 are connected to the inputs of decimal counters and decoders 6-9, made on the K115IE2 and K155ID1 microcircuits. (To help the radio amateur: collection, issue 86. - M .: DOSAAF, 1984, p. 9-13). The outputs of the decoders 6-9 are connected to the display units 10-13, which are digital discharge lamps IN-8. At the same time, the outputs of the decoders 6–9 are connected by a decimal counter 14 made on the K155IE2 microcircuit. The output of the decimal counter 14 is connected to the input of the counting single-channel device 15 (ПСО 2-08) and simultaneously with the input of the error calculation block 16, executed on the K155IE5 chip (To help the radio amateur: collection, issue 93. - M .: DOSAAF, 1986, p. . 20). Button 17 is associated with the operator, the counting single-channel device 18 (PSO 2-08) and the error calculation unit 16, performed on the K155IE5 chip. The power source (BP1, 2-12) is not shown in the block diagram. It feeds all electronic circuits, except for devices ПСО 2-08.

 When you turn on the device, numbers appear on the indicators. The test person, when the specified number appears on the indicator lamps, presses the button 17, supplying a signal to the meter 18 and the error calculation unit 16. Block 5 includes blocks 1-4 generating electric pulses of different frequencies, at the output of 1-4 blocks there are comparison elements allowing passage pulses under the condition of a positive period on the generator 5. In this case, the pulses acted on the decimal counters and decoders at their outputs, which decoded and presented the received information in the form of numbers from 0 to 9, glowing in cylinder of a discharge lamp. The pulses of the selected digit acted through the adder (block 14) on the even device (block 15). At the same time, the signal was fed to a reversible decimal counter (block 16).

 The subjects performing the functions of the operators had to follow the numbers appearing on the indicators. In the case of the appearance of a given digit, they are pressed by a button (block 17), the counter (block 18) recorded this. When two or more given digits appear simultaneously, the subject pressed the button the corresponding number of times. The error value - according to the difference in the readings of blocks 15 and 18 - was found by the error calculation block (16). By its size, they judged the quality of the focused activity of the subjects, the degree of their visual fatigue and made recommendations on the suitability of the subjects.

 Example 1. M.V., 20 years old, the student was observed for 1 h in laboratory conditions. The data on errors in the recognition of the check digit are obtained, are given in table. 1.

 Example 2. A group of five people, all male students aged 17-22 years, during 1 hour of observation showed data on errors in recognizing their control figures, are given in table. 2.

 The specified method can be used to simulate the visual work of operators in laboratory conditions. It is possible to use this method for training and professional selection of operators.

List of references
1. Copyright certificate N 1598969, cl. A 61 B 5/16 "Method for the determination of human fatigue."

 2. V. M. Volkov, V. E. Serednyakov. Visual fatigue in laboratory modeling of visual load. Collection: Questions of physiology and psychology of work. Yaroslavl, Yaroslavl State University, 1976, p. 10-20.

Claims (1)

 A method for diagnosing a person’s functional state when the subjects identify a given number from 0 to 9, compare the number of counted presentations with the actual number of presentations of this figure and determine the working capacity by the error value, characterized in that the numbers are presented simultaneously, the presentation time is set in the range from 0.5 up to 1 s, as well as the period of time after which the presentation is repeated in the range from 1 to 5 s, and the specified parameters are constant throughout the experiment.

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