Measuring reaction times in adolescents and adults. Human reaction time: history, theory, current state and practical significance of chronometric research Measuring human reaction time

Municipal budgetary institution "Rabocheostrovskaya secondary school" of the Kemsky district of the Republic of Karelia "Measuring human reaction time using a ruler" Research work in physics Completed by: Alexander Karyapin. Student 10 "B" class Project leader: Bukhalova Marina Nikolaevna Rabocheostrovsk, 2013

Relevance of the work: With the increasing pace of life, the problem of reducing reaction time to a stimulus is becoming more and more urgent every year, which is why many researchers are turning to this topic. The research we conduct will be useful to students, vehicle drivers, as well as people in professions where a quick response is necessary.

Defining the problem How to measure a person’s reaction time using an ordinary student ruler (!)? Do you know what human reaction time is? Did you know that the reaction depends on the age, fitness and well-being of the person... Reaction time is one of the important criteria for selecting drivers, operators, pilots, and astronauts.

Research objectives: find educational material in additional literature, Internet resources and the media; study the laws of free fall of bodies; use a ruler to explore the reaction time of students in our class during the school day; analyze the results of the experiment; draw conclusions.

Physical foundations of the research method If you catch the ruler immediately after the fall begins, then by its section “between the fingers” - the mark where we held it at the beginning, and at which it was caught, you can judge how long it took to fall. This will be the person’s reaction time. It remains to connect the path h and time t. How to do it?

Program for calculating data: The next stage of my work is preparing a microcalculator and drawing up a sequence of operations on it. We get the following program: put the number 0.04515 into the memory of the microcalculator, type h (in cm) on the indicator, extract the root of h, multiply by 0.04515 (from memory), and get the answer. We calculate the time t 1 (for h 1 = 1 cm), t 2 (for h 2 = 2 cm). We round each answer to three significant figures and enter it into the table

Results table Distance, cm Time, s

Results table: Distance, cm Time, s

Last name 1 lesson 2 lesson 3 lesson 4 lesson Albul Markitantov Kuntu Vereshchagina Kupriyanova Karyapin Ipatova Staina Emelyanova Egorov Boyarchenko Experienced data

Lesson 1 lesson 2 lesson 3 lesson 4 lesson Average value Experimental data

Research results The highest reaction time, and therefore the slowest reaction of students in our class, occurs in the first lesson in the schedule. The reaction to external influence and perception of the learning process in the second and fourth lessons improves significantly. In the third lesson according to the schedule, the reaction decreases again, the assimilation of educational material worsens

Subject Difficulty coefficient Physics 12 Geometry, chemistry 11 Algebra 10 Russian 9 Literature, foreign language 8 Biology 7 Computer science, economics 6 History, social studies, MHC5 Astronomy 4 Geography, ecology 3 Lifestyle, local history 2 Physical education 1 Subject difficulty scale

Good to know Age has a significant impact on reaction time Smoking habit increases reaction time to an event Reaction time in women is not significantly better than in men Reaction time in the presence of external stimuli increases significantly

Resources vremya-reakcii-cheloveka/ vremya-reakcii-cheloveka/

The invention relates to medicine and is intended to determine the reaction time of a person to a moving object. The subject is presented with a closed contour on the video monitor screen, which is a limiting contour, inside of which there is a mark - a contour of arbitrary size and configuration with a point object. A point object moves inside the bounding contour, reflecting from its internal boundary according to the principle “the angle of incidence is equal to the angle of reflection.” The subject, observing the movement of a point object at the moment of the supposed intersection of the contour of the mark by a moving point object, presses the “Stop” button to stop the movement of the point object along the trajectory. Then the error of mismatch between the point object and the contour of the mark is calculated - the time of the delay error with a positive sign or the lead time with a negative sign, and after a given time the movement of the point object along the trajectory is resumed. The subject performs the described procedure a specified number of times, after which the person’s reaction time to a moving object is calculated using the formula:

where t i is the time of the i-th delay error with a positive sign or lead error with a negative sign, ms; n is the number of tests. The method makes it possible to increase the reliability of determining a person's reaction time to a moving object by changing the trajectory of a point object. 1 ill.

The invention relates to medicine and is intended to determine the human reaction time to a moving object (RDO).

One of the methods for increasing the reliability and efficiency of a person’s professional activity is diagnosing and predicting his functional state. A simple and fairly accurate psychophysiological indicator of the functional state is the reaction time to a moving object. At the same time, the reaction to a moving object is a complex spatiotemporal reflex and is used as a test to assess the level of relationship between the processes of excitation and inhibition in the cerebral cortex, which necessitates the accuracy of its determination.

There is a known method for determining a person’s reaction time to a moving object, according to which the subjects are presented with the dial of a conventional stopwatch, one division of which is equal to 0.01 sec. Subjects, using the command “Can,” press a button to start the stopwatch and stop it when the hand reaches the specified division on the dial. 13 measurements are taken, three of which are considered indicative and are not taken into account when estimating the reaction time to a moving object. An indicator of the reaction to a moving object is the average value of lag errors and the average value of lead errors. To estimate the average value of delay errors, the sum of deviations with a positive sign and the number of errors of this kind are calculated. Dividing the total value of errors by their number gives the desired value. A criterion characterizing the average value of anticipation errors is calculated in a similar way. A comparison of the calculated average values ​​gives an idea of ​​the predominance of the average value of delay or lead errors, that is, the reaction to a moving object.

There is a known method for determining a person’s reaction time to a moving object, during which the subject is presented with a circle on the screen of a video monitor on which a cursor and a mark indicating “Stop” are placed. To ensure the cursor moves in a circle, the test subject holds the control panel button pressed with a probe. At the moment the cursor supposedly coincides with the mark, the subject presses the remote control button with the probe. By the number of leading, lagging and accurate reactions, the ratio of the processes of inhibition and excitation in the central nervous system is judged, that is, the assessment of the reaction to a moving object.

The closest in technical essence is a method for assessing a person’s reaction time to a moving object by presenting to the subject on the screen of a video monitor a circle on which a mark and a point object are placed, according to which the point object moves at a given speed along the circle, at the moment of the supposed coincidence of the position of the moving point object with mark, the subject by pressing the “Stop” button stops the movement of the point object along the circle, then calculates the mismatch error between the point object and the mark - the time of the delay error with a positive sign or the lead time with a negative sign, and after a specified time the movement of the point object along the circle is resumed, the described procedure is repeated as specified number of times, after which the estimate of the reaction time T p of a person to a moving object is calculated as the arithmetic mean according to the formula:

where t i is the i-th delay error with a positive sign or lead error with a negative sign, ms; n is the number of stops of a point object in the area of ​​the mark position.

The disadvantage of the known methods is the unreliable determination of the ability to predict the course of events, since in the known methods the movement of a point object is carried out along a predetermined trajectory, which does not change during the testing process. As a result of this, the effect of habituation of the subject and his adaptation to the testing conditions is observed.

The technical result of the proposed method for determining a person’s reaction time to a moving object is to increase reliability by changing the trajectory of a point object.

The technical result is achieved by the fact that the subject is presented with a closed contour with a point object and a mark on the video monitor screen, the point object moves at a given speed along a given trajectory, the subject, by pressing the “Stop” button, stops the movement of the point object along the trajectory, and the mismatch error is calculated - the delay error time with a positive sign or lead - with a negative sign, after a given time the movement of the point object along the trajectory is resumed, the described procedure is repeated a given number of times, after which the reaction time T p of a person to a moving object is calculated as the arithmetic mean value according to the formula:

where t i is the time of the i-th delay error with a positive sign or lead error with a negative sign, ms; n is the number of tests.

Moreover, what is new is that the subject is presented with a closed contour, which is a limiting contour, within which a mark is located - a contour of arbitrary size and configuration, a point object moves inside the limiting contour, reflecting from its internal boundary according to the principle “the angle of incidence is equal to the angle of reflection”, the subject presses a button “Stop” stops the movement of a point object when it crosses the contour of the mark.

Figure 1 shows the limiting contour presented to the subject on the video monitor screen, where 1 is the limiting contour, 2 is the mark-contour, 3 is a point object moving at a given speed along a trajectory, 4 is the trajectory of a point object.

The proposed method for determining the reaction time of a person to a moving object is carried out as follows.

The subject is presented with a closed contour on the video monitor screen, which is limiting, inside which there is a mark - a contour of arbitrary size and configuration.

A point object moves inside the bounding contour, reflecting from its internal boundary according to the principle “the angle of incidence is equal to the angle of reflection.”

The subject, observing the movement of a point object at the moment of the supposed intersection of the contour of the mark by a moving point object, presses the “Stop” button to stop the movement of the point object along the trajectory.

Then the error of mismatch between the point object and the contour of the mark is calculated - the time of the delay or lead error, and after a specified time the movement of the point object along the trajectory is resumed.

The subject performs the described procedure a specified number of times, after which the person’s reaction time to a moving object is calculated using formula (1).

Thus, the proposed method for determining a person’s reaction time to a moving object has new properties that provide a positive effect.

Subject A., 20 years old, was presented with a bounding rectangle, a mark in the form of a square outline, and a point object moving at a given speed in an arbitrary direction inside the bounding rectangle on the screen of a video monitor of a personal computer compatible with an IBM PC. The point object moved inside the bounding rectangle, reflecting from its inner boundary according to the principle “the angle of incidence is equal to the angle of reflection.”

The subject, observing the movement of a point object at the moment of the supposed intersection of the contour of a square with a moving point object, pressed the “Space” key on the computer keyboard, which performs the function of the “Stop” button.

The computer, at the moment of pressing the “Space” key, stopped the movement of the point object along the trajectory, displayed the position of the point object on the video monitor screen in the place where its movement was stopped, calculated the error in the mismatch of the positions of the point object and the contour of the mark - the time of the delay error with a positive sign or lead time with a negative sign, entered the error time value with the corresponding sign into the memory device and after 1 s continued the movement of the point object along the trajectory.

The subject, in accordance with the recommendations, made 13 stops of the movement of a point object in the area of ​​the mark’s contour, the first three of which were not taken into account when assessing the ability to predict the course of events. As a result of testing, the following error values ​​for mismatch between the positions of the point object and the mark contour were obtained: 47; 24; -32; -18; 44; 6; -25; -41; 18; 22 ms.

The human reaction time to a moving object, calculated using formula (1), is 4.5 ms, which indicates a slight predominance of inhibition processes over excitation processes in the nervous system of subject A., that is, a state close to the balance of nervous processes.

Subject B., 18 years old, similar to subject A., performed a test to determine the reaction time of a person to a moving object. As a result of testing, the following error values ​​for mismatch between the positions of the point object and the mark contour were obtained: 24; 46; 16; -33; -17; 25; 51; 3; -34; 20 ms.

The human reaction time to a moving object, calculated using formula (1), is 10.1 ms, which indicates a delayed response and the predominance of inhibition processes over excitation processes in the nervous system of subject B.

Thus, it has been established that the proposed method for determining a person’s reaction time to a moving object makes it possible to increase the reliability of the method by changing the trajectory of a point object and eliminating the habituation effect of the subject.

The positive effect of the proposed method for determining the ability to predict the course of events is confirmed by the results of an experimental study on a group of 10 subjects.

Thus, the proposed method for determining a person’s reaction time to a moving object makes it possible to increase the reliability of the method by changing the trajectory of a point object and eliminating the habituation effect of the subject.

Information sources

1. Surnina O.E., Lebedeva E.V. Gender and age differences in reaction time to a moving object in children and adults // Human Physiology. - 2001. - T. 27, No. 4. - P.56-60.

2. Karaulova N.I. Possibilities of using the reaction to a moving object in assessing the results of training // Human Physiology. - 1982. - T. 8, No. 4. - P.653-660.

3. Methods and portable equipment for studying individual psychological differences in humans / N.M. Peisakhov, A.P. Kashin, G.G. Baranov, R.G. Vagapov; Ed. V.M. Shadrina. - Kazan: Publishing house Kazansk. University, 1976. - 238 p.

4. Maslova O.I., Goryunova A.V., Guryeva M.B. and others. Application of test computer systems in the diagnosis of cognitive impairment in attention deficit hyperactivity disorder in school children // Medical technology. - 2005. - No. 1. - P.7-13.

5. RF Patent No. 2326595. Method for assessing a person’s reaction time to a moving object / Pesoshin A.V., Petukhov I.V., Rozhentsov V.V. BI 17. - 17 p.

A method for determining a person’s reaction time to a moving object, which consists in presenting to the subject on the screen of a video monitor a closed loop with a point object and a mark; the point object moves at a given speed along a given trajectory; the subject, by pressing the “Stop” button, stops the movement of the point object along the trajectory, and the error is calculated mismatch - the time of the delay error with a positive sign or the lead time - with a negative sign, after a given time the motion of the point object along the trajectory is resumed, the described procedure is repeated a given number of times, after which the reaction time Тtr of a person to a moving object is calculated as the arithmetic mean value according to the formula

where t i is the time of the i-th delay error with a positive sign or lead error with a negative sign, ms; n is the number of tests, characterized in that the subject is presented with a closed contour, which is a limiting contour, within which a mark is located - a contour of arbitrary size and configuration, a point object moves inside the limiting contour, reflecting from its internal boundary according to the principle “the angle of incidence is equal to the angle of reflection”, The subject, by pressing the “Stop” button, stops the movement of the point object when it crosses the contour of the mark.

Similar patents:

The invention relates to the field of medicine and social work, namely rehabilitation, balneology, medical and social expertise, neurology, healthcare organization, social psychology, and is intended to evaluate the effectiveness of rehabilitation of persons with disabilities over 18 years of age in rehabilitation departments of healthcare and social service institutions.

The invention relates to the field of medical equipment, as well as to sports and gaming simulators. .

The invention relates to the field of medicine, namely to methods for functional diagnostics of a person, and is intended for professional psychophysiological selection of passenger train drivers to work without an assistant.

The invention relates to the field of medicine, psychology and can be used to assess the psychophysiological state of a person, in particular, for psychodiagnostics in the field of psychology and psychotherapy, to assess the physical condition, as well as to monitor the effectiveness of the rehabilitation process.

School research conference “In the world of research”

Determination of human reaction speed

(Research work)

Polivtseva Larisa Sergeevna,

MAOU "Kyiv Secondary School",

Supervisor:

Shingareva Vera Sergeevna,

physics and mathematics teacher,

MAOU "Kyiv Secondary School"

Introduction

With the increasing pace of life, the problem of reducing reaction time to a stimulus becomes more and more urgent every year, so many researchers are turning to this topic.

The method for measuring human reaction time surprised and interested me. Firstly, simplicity, this is not difficult to do with an ordinary ruler. Secondly, the importance of knowing about it. For example, reaction time is one of the important criteria for selecting drivers, operators, pilots, astronauts and people of other professions. Anyone at home, at work, or on the street can encounter danger at any moment, then his health will directly depend on his speed of reaction.

I think that after such information, many teenagers who are on the path to choosing a profession (like me) have questions: “What is my reaction time? What does it depend on? Is it possible to train yourself to improve an unsatisfactory result? Will I be able to be a driver, pilot or operator at a nuclear power plant?

Suppose that if you exercise or learn how to react to stimuli, your reaction time improves.

Purpose The work is to measure a person’s reaction time at different times of the day, using the laws of free fall of bodies and an ordinary student ruler.

Object of study– students of MAOU Kiev Secondary School

Subject of study- reaction time

tasks:

study the literature on human reaction time;

conduct experiments and analyze their results;

suggest ways to improve unsatisfactory results.

Research methods:

empirical

theoretical

Chapter 1. Theoretical part

1.1 What is human reaction speed?

Reaction speed is one of the main qualities of a living organism. It is very important to quickly respond to external irritants, because some of them can be dangerous or even fatal.

Reaction time is one of the most important qualities that determines the result of a competition. From the onset of the stimulus to the moment of reaction, a certain time always passes, after which the muscular mechanisms of response are activated, the speed of which already depends on the speed of body movements. The delay time is determined by the metabolic rate and is an individual feature of each organism. It cannot be trained because it is impossible to increase the speed of transmission of nerve impulses.

Reaction time is the length from the beginning of a signal to the human body’s reaction to this signal. In humans, the average reaction time to a visual signal is: 0.1-0.3 seconds.

Oddly enough, a person’s leadership qualities also depend on reaction time. And also, one of the most important qualities of a driver is his reaction time to changes in road conditions.

You need to learn to respond to stimuli that precede a dangerous action. For example, you should react not to the blow itself, but to the preparation for it - after all, before hitting, the enemy will definitely look at the target, change his position, tense his muscles, inhale... There is more than enough time. You just need to develop a conditioned reflex, plant a new stimulus and response to it in the subconscious.

1.2 Free fall of bodies

Free fall is the movement of a body under the influence of gravity. Since the force of gravity acting on every body near the surface of the earth is constant, a freely falling body must move with constant acceleration, i.e. uniformly accelerated (this follows from Newton's second law).

The peculiarity of free fall is that all bodies in a given place on the earth fall with the same acceleration. This acceleration is called the acceleration of gravity. It is usually denoted by the letter g (the first letter of the Latin word gravitas, which means “heaviness.”

There are different ways to determine the value of g with great accuracy (for example, up to 0.00001 m/s 2). But when solving problems in a school physics course, where high accuracy of the result is not required, a value of 9.8 m/s 2 or even 10 m/s 2 is usually used.

Since in our example the motion of a freely falling body is uniformly accelerated motion without an initial speed, the displacements are calculated using the formula: s = g t 2 / 2 or h = g t 2 / 2 (i.e. s = h)

Chapter 2. Practical part

2.1. Study of human reaction speed.

Take a wooden ruler 50 cm long. A mark is made on the wall.

Then, distracting the attention of the experiment participant, he lets the ruler fall into free fall. The participant must stop the ruler from falling as quickly as he can.

Marks the new position of the ruler notch and measures its flight (h), i.e. distance between marks on the wall.

The reaction rate is calculated using the formula: t= , where

g - free fall acceleration equal to 9.8 [m/s 2 ].

t – reaction speed, [s];

h - distance between marks on the wall [m]

2.2 Research results

The measurement results are entered into the table. The subjects (students in grades 7 and 11) were entered into a table with information about their attendance at sports sections, as well as their interest in their future profession. (Appendix I)

Who was examined?	In the morning,after 1 th lesson	During the day,after 6th lesson	Playing sports?	Propensity for the profession
7th grade boys
				Driver
7th grade girls
				Doctor
Boys of 11th grade
				Military
				Teacher
				Does not know
11th grade girls
				Lawyer
				Salesman
				hairdresser

Analysis of the results obtained:

The “-” sign means that the participant in the experiment did not have time to stop the ruler before it touched the floor.

In humans, the average reaction time to a visual signal is: 0.1-0.3 seconds. The measurements showed that all the examined adolescents had a satisfactory reaction time.

To identify the dependence of reaction time results on human fatigue, experiments were carried out after the first lesson (this time is considered to indicate that the student’s body has already woken up and therefore any monitoring at school is carried out in the second lesson), and then at the end of the school day (after the sixth lesson).

Research has shown that most students have improved reaction times, i.e. inhibition of actions is manifested.

The opinion that adolescents involved in sports has attending sports clubs in volleyball, basketball, time reactions are better than those of guys who are not interested in sports games.

Motor reactions must be carried out at the level of conditioned reflexes, and this requires serious training. Therefore, the most important advice arising from and analysis of research is: playing sports.

Sports relay races, where the signal enters the brain through touch, are very effective in developing reaction speed. That is, you need to take action as quickly as possible after the previous player touches you.

You can also use the children's game "Clapperboards", the signal enters the brain through the organs of vision - the eyes. The first partner stands and positions his open palm so that it is convenient for the second to hit it. For example, he stands sideways to the second person, holding his open palm in front of him. The second partner hits the palm of the first at random times. The task of the first is to remove the palm, the task of the second is to hit. You can keep score. Then the partners change.

The principle inherent in this game can be transferred to other technical actions, for example, cutting and avoiding kicks at the lower level.

Conclusion

In this research work, a human mechanical parameter was experimentally determined: human reaction speed.

When measuring the time and reaction speed of the experiment participants, it was found that many participants had a very slow reaction speed. For some participants in the experiment, the reaction speed depended on the characteristics of the signal source, for others it did not. Based on the results of the experiments, we can conclude that the reaction speed is different for all people from birth - it is determined by the characteristics of the nervous system, emotional and mental characteristics of a person. However, experiments have shown that when you feel unwell or are very tired, the reaction speed worsens.

Many professions require intense attention and good reaction speed, therefore, when choosing a profession and hiring, these characteristics of a person are important. I see the practical value of my work in the fact that every teenager, having learned his reaction time, realizes the need to improve the result, will work on himself and, perhaps, this will influence his choice of profession.

At home, at school, and on the street - at any moment a teenager will be able to protect himself from life-threatening exposure.

Literature

1. M.V. Volkenshtein “Biophysics”. – M.: Nauka, 1988

2. Peryshkin A.V., Gutnik E.M. Physics 9th grade. - M.: Education, 2013.

3. A.B. Rubin “Biophysics”. – M.: Higher School, 1987

4. K.Yu. Bogdanov “Physicist visiting a biologist.” – M.: Nauka, 1986

5. V.R. Ilchenko “Crossroads of physics, chemistry, biology.” – M.: Education, 2000

6. A.G. Khripkova “Human Physiology”. –M.: Education, 2013

7. http://www.psychology-online.net/articles/doc-1988.html

Appendix I

Laboratory work “Measuring the time of a simple sensorimotor reaction”

Purpose of laboratory work:

Measuring the time of a simple sensorimotor reaction to light and sound stimuli.

Devices and accessories:

Psychophysiological testing device “Reflexometer”.

Brief theory:

Human reaction time is the time interval from the beginning of exposure to any irritant to the body’s response.

Consists of three phases: the time of passage of nerve impulses from receptors to the cerebral cortex; the time required for the perception of nerve impulses by the brain and the organization of a response in the central nervous system; the body's response time. The reaction time depends on the type of stimulus (sound, light, temperature, pressure, etc.) and its intensity, the body’s training to perceive this stimulus, its expectedness, etc.

The reaction time to stimuli of different modalities is different. The shortest reaction time is obtained in response to auditory stimuli, longer - to light, the longest - to olfactory and tactile.

According to the degree of complexity, a person’s voluntary reactions can be divided into the following four types:

1 simple sensorimotor reaction;

2 sensorimotor reaction differences;

3 sensorimotor reaction of choice;

4 reaction to a moving object.

1 A simple sensorimotor reaction in psychology is a reaction that occurs under the conditions of presenting one pre-known signal and receiving one specific response.

For example, in response to sound, light, tactile, etc. signals, a person must carry out a certain action as quickly as possible - press a key or pronounce a certain syllable. Research shows that at suprathreshold intensity of the stimulus, the time of a simple reaction is determined mainly by the physical nature of the stimulus and the characteristics of the perceiving receptor. The highest speed of a simple reaction was obtained when using sound and tactile signals (105 - 180 ms). The speed of reaction to the visual signal turned out to be significantly slower (150 - 225 ms).

This is explained by the fact that the reception time of sound and tactile stimuli is much shorter than the reaction time of a visual stimulus, since in the latter case a significant proportion of the time is occupied by the photochemical process that converts light energy into a nerve impulse.

2 Sensorimotor discrimination reaction refers to a reaction that is produced under conditions when a person must react only to one of two or more signals (letters, sounds, syllables), and, accordingly, a response action must be performed only to this signal.

3 The sensorimotor reaction of choice also occurs when two or more signals are presented, but on the condition that you need to respond to each of them with your own specific action. Compared with the simple reaction time, the discrimination reaction time and the choice reaction time are noticeably longer.

The reaction time to stimuli of different modalities is different. The shortest reaction time is obtained in response to auditory stimuli, longer - to light, the longest - to olfactory and tactile.

When controlling equipment, in addition to the reaction time, it is also necessary to take into account the time of movement of the organs of the human body and the time of interaction of the operator with the controls (Table 4).

Table 4 - Reaction time values ​​for various body movements

Dependence of reaction time on the level of training, gender, age and various influences on the body.

It has been shown experimentally (N.I. Krylov, 1957, N.I. Chuprikova, 1957, E.I. Boyko, 1964, E.N. Surkov, 1984, V.P. Ozerov, 1989) that:

1 Under the influence of training, the reaction time is not only shortened, but also stabilized, i.e. becomes less susceptible to various kinds of influences.

2 The shortening of reaction time is most significant in the first days of performing the corresponding exercises.

3 The simple reaction is influenced by exercise to a noticeably lesser extent than the choice reaction. In particular, after just one day of training, the choice reaction time can be reduced by 30-40%, while a simple sensorimotor reaction can be reduced by only 10%.

What are the reasons for shorter reaction times after appropriate training? It is known that any new stimulus first causes an indicative reaction with a more or less extensive and prolonged irradiation of the excitatory process throughout the cerebral cortex, which is then replaced by a concentration phase. As the stimulus is repeated, habituation occurs, which is accompanied by less and less pronounced irradiation of excitation with a simultaneous increase in the dynamism of the emerging nervous processes. The gradual reduction of the irradiation phase and the achievement of a certain level of chronic (or static) concentration of the excitatory process in the cortex, apparently, are one of the most important reasons for the shortening of reaction time during training.

The second reason, closely related to the first, is the increasing persistence of cortical foci of excitation as conditioned connections become stronger. The third reason is associated with a change in the very structure of temporary connections, the replacement of more complex secondary-signal associations with simpler primary-signal ones.

Starting from 3.5-4 and up to 18-20 years, the reaction time is steadily decreasing. Then it stabilizes, and after 40 years, as we age, it gradually increases by about 1.5 times (A.G. Usov, 1960).

A number of studies (E.P. Ilyin, 1983, E.N. Surkov, 1984, Ozerov, 1989) note gender differences, consisting in the fact that the average reaction time in girls, compared to boys, and in women, compared with men, somewhat longer.

Table 5 - Dependence of the time of a simple sensorimotor reaction of a person on the physical and psycho-emotional state of a person

Installation description:

The “Reflexometer” device, which uses light and sound signals as a stimulus, allows you to measure time.

The installation consists of a signal conditioning unit with an alphanumeric indicator (1); a control unit with start (stop) buttons for the recording device (3) and a light (sound) signal unit (2). Test results are displayed on an alphanumeric indicator and stored in the microcontroller's memory.

In this device, the microcontroller performs all the main functions, namely, it supplies test signals, measures response time, displays information on an alphanumeric indicator and stores it in its non-volatile memory (EEPROM - electrically erasable reprogrammable Read Only Memory (ROM)).

The device is controlled using the (Start/Reset) button, which is pressed to successively switch operating modes, or with a computer mouse. Pressing is accompanied by a sound signal.

The device diagram is shown in Figure 6.

Figure 6 - Electrical circuit of the reflexometer

The clock frequency of the microcontroller is stabilized by a ZQ1 quartz resonator. Its frequency (4.096 MHz) is chosen so that it is convenient to use it for measuring time intervals. Button SB1 is connected to port line RA0 (pin 17) of the microcontroller through current-limiting resistor R3. If its contacts are open, there is a low level on this port line; if they are closed, there is a high level. LCD HG1 with a built-in controller is used to display information. It displays two lines of sixteen characters each and is equipped with LED backlighting.

The indicator is controlled by the DD1 microcontroller via lines RBO, RB1 and RB4--RB7, data is loaded in nibbles. By selecting resistor R7, the desired image contrast is set. On port line RB2, a control signal is generated for field-effect transistor VT1, which turns on (turns off) the LCD backlight, resistor R6 is current-limiting. A pulse signal with a frequency of 4 kHz is generated on port line RB3, which is supplied through resistor R4 to the acoustic emitter HA1.

The device is powered from an external source of direct or alternating voltage 8... 12 V, the current consumption does not exceed 130 mA. Diode bridge VD1 rectifies alternating voltage or supplies direct voltage to the elements of the device in the required polarity. The supply voltage of the microcontroller and LCD is stabilized by the integrated stabilizer DA1, capacitors C1-C3, C6, C7 are smoothing.

After supplying the supply voltage, data is read from the EEPROM of the microcontroller. A short single beep sounds and the HG1 indicator lights up. The inscription “Record Record” appears in its top line. The best result of the current session is displayed on the right - when you first turn it on, this is the maximum possible measurable time interval - 9.999 s. On the left is the best result for the entire operating time of the device, also 9.999 s when turned on for the first time.

Before pressing the SB1 button, the value of the duration of the pre-start pause is generated. It ranges from 1 to 8.2 s and is random. After pressing the SB1 button and releasing it, the countdown of the pre-start pause will begin, the LCD information will be reset, and its backlight will turn off. Then the acoustic emitter emits a single sound signal. After the pause has expired, the start moment comes - the LCD backlight turns on, a sound signal (light signal) sounds and the time countdown begins. The device measures the reaction time in the range of 0.001...9.999 in steps of 0.001 s.

If the subject does not press a button within 9.999 s, the beep stops and the instrument returns to the initial state where the best results are displayed. When you press the button within the specified time interval, the counting stops and the sound signal turns off. The inscription “Reaction Reaction” appears on the top line of the LCD, the number of measurements (maximum 255) appears on the bottom left, and the measured reaction time appears on the right.

Next, the obtained result is compared with the best results for the current and for the entire operating time of the device. When a new record is recorded, data is rewritten in the EEPROM of the microcontroller. After pressing the SB 1 button and releasing it, the device returns to its initial state. If you press the button before the start (false start), a double beep will sound, the LCD backlight will turn on and the inscription “F.start F. start” will appear in the top line. After a few seconds, the device will return to its original state.

Progress:

1 Turn on the device by setting the toggle switch to the “On” position. After supplying the supply voltage, a short single beep sounds and the indicator backlight turns on. The inscription “Record Record” appears in its top line. The best result of the current session is displayed on the right, and the best result for the entire operating time of the device is displayed on the left.

2 Sit at the table in a comfortable position. The subject should look only at the block of light (sound) signals. Move the right toggle switch to the “Sound” position.

3 Place your hand on the installation control panel (Start/Reset button, computer mouse) so that the index finger of your right (left) hand rests freely on the button.

4 Press the Start/Reset button. After pressing the button and releasing it, the countdown of the pre-start pause will begin, the LCD information will be reset, and its backlight will turn off. Then the acoustic emitter gives a single sound signal and the countdown begins. After the pause expires, the start moment comes - the LCD backlight turns on, a beep sounds and the time countdown begins. The device measures the reaction time in the range of 0.001...9.999 in steps of 0.001 s.

5 When a sound signal appears, you must press the mouse button as quickly as possible and stop counting; the sound signal turns off. The inscription “Reaction Reaction” appears on the top line of the LCD, the number of measurements (maximum 255) appears on the bottom left, and the measured reaction time appears on the right.

6 Press the “Start/Reset” button, as a result of which the device returns to its original state. If you press the mouse button before the start (false start), a double beep will sound, the LCD backlight will turn on and the inscription “F.start F. start” will appear in the top line. After a few seconds the device will return to its original state.

7 The measurement must be carried out 10 to 30 times, then find the average reaction time. Switching the toggle switch to the “Light” position, repeat steps 1-13.

8 From the results obtained, subtract the time spent moving the phalanx of the finger (0.17 sec.). Compare the resulting reaction time to light and sound stimuli with the values ​​given in Table 3.

Conclusions: for this laboratory work, a psychophysiological testing device “Reflexometer” was created with a detailed description of the tasks and instructions for performing the work.

To determine the speed of the sensorimotor reaction, volunteers of both sexes aged from 19 to 23 years in different psycho-emotional states were studied. The test was carried out in conditions of silence and the absence of other stimuli, in a comfortable body position and with the presence of an elbow support to reduce the influence of static contraction of the arm muscles. To determine the speed of a simple sensorimotor reaction, subjects were presented with visual stimuli in the form of a green lamp with a diameter of 0.3 cm and a sound signal. When the required green signal appears, the volunteer’s task is to press the key as quickly as possible. The time between the appearance of signals was random and ranged from 1 to 7 seconds. The subjects were warned that in each series of the study they would first be presented with 10 light signals (a study of the time of a simple sensorimotor reaction), then 10 sound signals.

The test was carried out on 15 subjects, 5 of whom were in an inhibited state.

Only the time of the sensorimotor reaction was assessed; errors in performing the task were excluded. In order to combat artifacts, the first values ​​in each reaction whose time exceeded 2000 ms were excluded. The latter obviously exceed the time of the sensorimotor reaction and are most often associated with the distraction of subjects from performing the test.

According to the results of the research, it follows that for ten students, the average reaction time to a light stimulus is approximately 0.327 s, to a sound stimulus - 0.302 s. These values ​​correspond to the norm for an ordinary, untrained person. In five students who were in a state of inhibition caused by short sleep, the average reaction time to a light stimulus was equal to 0.497, to a sound stimulus - 0.472 s. These values ​​correspond to a low simple sensorimotor reaction.

However, these results are the norm, because Human reaction time ranges from 0.1 to 0.5 seconds. For example, the duration of the driver’s response to traffic signals in a populated area is 0.3-0.4 s. Reaction time depends on the degree of training of a person. For more trained people, the reaction time is quite low, approximately 0.13-0.15 s. Reaction time is affected by factors such as fatigue, inattention, and the use of tonics or alcohol. When taking a small dose of alcohol, the reaction time increases by 2-4 times.

Goal of the work.
Measure and compare the time of a simple sensorimotor reaction to light and sound stimuli under normal and extreme conditions.

Equipment.
1. Reaction time meter “Temp”
2. Microcalculator.
Theoretical introduction
Since mental processes are phenomena that develop over time, no behavioral act, no conditioned or unconditioned reaction of the body to the action of a stimulus (stimulus) can be instantaneous. As a rule, it is characterized by a certain reaction time, including motor and latent periods.
The motor period is the time of immediate response.
The latent (hidden) period is the time interval between the moment the stimulus appears and the beginning of the response to it. There are three types of reaction:
1) a simple reaction, when a person reacts to the presentation of a previously known signal with a certain unambiguous answer;
2) a discrimination reaction, in which a clear response is expected to only one of several presented signals;
3) a choice reaction, consisting of presenting the subject with several signals, each of which has its own type of response.
Increasing the complexity of the reaction leads to an increase in reaction time. In the case of a simple sensorimotor (motor) reaction to an external stimulus, its latent period is determined by a number of physiological and psychological factors, primarily the inertia of the receptor. Thus, the retina begins to send electrical impulses along the optic nerve to the brain only 60-80 ms after the onset of the optical stimulus.
When exposed to a sound signal, time is required for the passage of impulses to the corresponding center of the brain, decoding of this impulse, development of a response program, and transmission of command impulses to the executive organ. That is why the organ of Corti begins to send impulses to the brain only
after completing eight complete oscillations of the sound acting on the ear.
Knowing the reaction time is necessary when designing those types of human activities where there is a time limit for performing certain actions (in aviation, astronautics, in modern automated control systems, in various types of transport). In theoretical terms, measuring reaction time is a fairly productive method for analyzing mental activity, its complexity and self-regulation.
Reaction time is one of the trainable manifestations of the human psyche. It is much shorter in people whose work involves the need for quick motor reactions (car drivers, pilots, boxers, tennis players, goalkeepers of football and hockey teams, etc.).
The period of the sensorimotor reaction is greatly influenced by the physiological and psychological state of a person (malaise, fatigue, mental fatigue, alcohol poisoning). Therefore, reaction time can be used as an indicator of changes in a person’s mental (emotional) state.
Exercise
1. Study the operating instructions for the “Temp” device.
2. Study the technique of measuring and assessing the time of a simple sensorimotor reaction to light and sound stimuli.
3. Measure the time of a simple sensorimotor reaction to a light stimulus tenfold.
4. Measure the time of a simple sensorimotor reaction to a sound stimulus tenfold.
5. Carry out a tenfold measurement of the time of a simple sensorimotor reaction to a light (sound) stimulus under conditions of exposure to an extreme factor.
6. Carry out mathematical processing of the obtained data (average values, variances, significance of differences), and analyze them.
7. Draw up a report on the work performed.

Progress of the task
When performing laboratory work, a “Temp” reaction time meter is used (Fig. 5), which makes it possible to quantitatively assess the test subject’s reaction time to light and sound stimuli. The device includes a device for presenting sound and light signals, recording the test subject's reaction time, designed in the form of an experimenter's panel, and a device for picking up stimuli, designed in the form of a test subject's panel. The panels of the subject and the experimenter are located on opposite sides of the device, which eliminates eye contact between the researcher and the subject.

(foto) Fig. 5. Reaction time meter “Temp”:
a - view from the experimenter’s panel; b - view from the side of the test subject’s panel
At the workplace there is a team of students (listeners) consisting of three people, alternately performing the roles of a subject, a protocol taker and an experimenter. Before performing work, each member of the team measures their heart rate by palpation or using a P-5 pulsograph, after which they take their place at the device and prepare to perform the task.

The experimenter turns on the device by placing the “Network” switch in the “On” position, and makes sure that it is ready for operation (turned on) when the “Network” light comes on. At this time, the subject becomes familiar with the location of the controls on the instrument panel and remembers the procedure for working with it. The protocol officer prepares the tables (Table 7).
Table 7
Subject's experimental data

View irritant	Test serial number
	1	2	3	L	5	G	7	8	9	10
Light
Sound

After the preparatory operations, the experimenter reminds about the actions of the subject and the protocolist during the experiment and warns about the start of the test.
If it is necessary to provide a light signal, the experimenter presses one of the 6 buttons located in the horizontal part of the panel. In this case, a display indicating the appearance of a light signal is displayed above the pressed button, the electric stopwatch is turned on, and a light appears on the test subject’s panel in one of the keys located under the inscription “Light”. The subject presses the illuminated key, trying to do it as quickly as possible, and its glow stops, as well as the glow of the display on the experimenter’s panel. The stopwatch stops, the recordkeeper takes the electric stopwatch readings and enters the data in the top row of the table corresponding to the light signal in experiment 1. After this, the experimenter resets the electric stopwatch readings by pressing the lever all the way, and the procedure is repeated.
If it is necessary to give a sound signal, the operating procedure is similar to that discussed with the only difference being that the experimenter sets the “Sound” switch to the “On” position. At this time the bell is turned on and
is a beep. The subject must press the illuminated key located under the “Sound” inscription. The sound signal disappears, and the recorder enters the data in the top line of the recording (reaction time to the sound stimulus).
An extreme mode of operation is created due to emotional instruction of the subject, for example, the protocolist or experimenter informs him about the low results of his response to a light (sound) signal and the requirement to respond faster.
The order of work of the team members remains the same, with the exception that before responding to a signal of a stressful nature, heart rate readings are taken from the subject, and the recorder enters the experiment data in the bottom line of the table of the corresponding signal (sound or light).
Experimental data processing
It is advisable to process experimental data based on the use of qualitative and quantitative methods.
Recommendations for processing experimental data.
1. Calculate the average value of the reaction time to a light signal under normal conditions (MS=CS), using formula (1).
2. Calculate the average value of the reaction time to a sound signal under normal conditions (M3=X3), using formula (1).
3. Calculate the average value of the reaction time to a light or sound signal in extreme conditions (MSE = HSE; mzz = xe), using formula (1).
4. Calculate the correlation coefficient (Rzh) of the reaction time to light and sound signals using formula (11).
5. Determine the correlation of the reaction under normal and extreme conditions (Doe) using formula (11).
6. Assess the reliability of differences in reaction time under normal and extreme conditions (CoE), using formula (8).
7. Assess the reliability of differences in response to light and sound signals (Ksz), using formula (8).

Contents of the report
1. Task.
2. Table with experimental data.
3. Calculation data for average reaction times, correlation coefficients, and reliability of differences.
4. Analysis and interpretation of the results obtained.
5. Substantiated conclusions on the work and recommendations for using the results obtained.
6. Date of completion of laboratory work and signature of the performer.