JS MEDICAL UNIVERSITY ASTANA
Department of Physiology
LECTURE
Subject: Overview of physiology as a science.
Number of hours: 2
Course: 2
Speciality: 051301 "General Medicine"
Author: Khamchiev KM
Astana, 2010.
Discussed and approved at faculty meeting
31, August 2010, the protocol number 2
Head of the Department _______________ Khamchiev KM
(Signature)
JS MEDICAL UNIVERSITY ASTANA
Department of Physiology
Lecture № 1.
Theme lecture: Overview of physiology as a science.
Purpose: To provide knowledge about the basic stages in the development of
physiology, the contribution of renowned scientists in the development of
physiological science, to formulate the basic principles of formation and regulation
of physiological functions,
Abstracts of lectures:
The Physiology - the science that can explain a man
what do his internal organs, while he lives "
G. Ratner
Introduction. The main stages of the development of physiology
Physiology (Greek physiologia; from physis - nature and logos - teaching) - one of
the oldest natural sciences. It examines the vital activity of the whole organism, its
parts, systems, organs and cells in close relationship with nature. History of
Physiology includes two periods: an empirical and experimental, which can be
divided into two phases - before and after the Pavlova.
Empirical period
The first presentation of the individual organs of the body began to take shape in
ancient times and are presented in the extant writings of the philosophers of the
ancient East, ancient Greece and ancient Rome.
In the classical period of the Middle Ages when the church was dominated by
scholasticism and pursued efforts of an experienced knowledge of nature, in the
development of science has stagnated.
In the Renaissance, anatomical and physiological, and natural science research
produced by A. Vesalius, M. Servet, R. Colombo, J. Fabrizio, G. Fallopian, G.
Galilei, S. Santoro and others, paved the way for future discoveries in the field
physiology.
Experimental period
Physiology as an independent science-based experimental methods of
investigation, has its origins from the works of William Harvey (Harvey, William,
1578-1657), which is mathematically calculated and experimentally substantiated
the theory of circulation.
From the standpoint of the laws of mechanics, scientists have attempted to
explain the work apparatus, the mechanism of respiration, kidney function, etc.
Enjoyed great popularity the concept of animal-machines which developed Wrens
Descartes (Descartes, Rene, 1596-1650), which extended the principle of
mechanistic movement and the nervous system of animals. He put forward the idea
of reflection as a reflection of the brain "animal spirits" that pass from one nerve to
another, and thus developed in the simplest form of reflex arc. (The term reflexus,
ie reflected, introduced in the physiology of the Czech scientist I. Prohaska, 17491820.) Using the laws of optics, Descartes tried to explain the work of the human
eye.
Outstanding achievement of the XVIII century. was the discovery of bioelectric
phenomena ("animal electricity"), in 1791 the Italian anatomist and physiologist
Luigi Galvani (Galvani, Luigi Aloisio, 1737-1798), which marked the beginning of
electrophysiology.
Among the founders of Physiology and Experimental Medicine, a distinguished
place is a German scientist Johannes Muller (Muller, Johannes Peter, 1801-1858),
a member of the Prussian (1834) and a foreign corresponding member Petersburg
Academy of Sciences. To Him belong the fundamental research and discoveries in
the field of physiology, pathology, embryology. In 1833 he formulated the basic
provisions of the reflex theory, which were further developed in the writings of
Sechenov and Pavlov.
In Russia, laying the foundation of the materialist trend in physiology due
primarily to the activities of Alexei Matveevitch Filomafitskiy (1807-1849) founder of Moscow's physiological school.
Together with the NI Pirogov, he developed a method of intravenous anesthesia, he
studied problems of physiology of respiration, digestion, blood transfusion
("Treatise on blood transfusion, 1848); create an apparatus for blood transfusion, a
mask for ether anesthesia, and other physiological instruments.
The founder of the neuro-muscular physiology German physiologist Emil Du BoisReymond (Du Bois-Reymond, Emile, 1818-1896), continuing the research started
Galvani and Volta, has developed new methods for electrophysiological
experiments and discovered the laws and phenomena of irritation galvanotonus
(1848). They also formulated molecular theory of bioelectric potentials.
Eminent French physiologist Claude Bernard (Bernard, Claude, 1813-1878)
studied in detail the physiological mechanisms and significance sokootdeleniya
digesting properties of saliva, gastric and pancreatic secretion for healthy and sick
body, putting thus the basis of experimental pathology.
Outstanding contribution to the reflex theory, which is one of the major theoretical
concepts of physiology and medicine, introduced the great Russian scientist, an
outstanding representative of Russian physiological school, and the founder of
scientific psychology Ivan Mikhailovich Sechenov (1829-1905).
Sechenov first proposed the idea of reflex-based mental activity and convincingly
proved that "all acts of conscious and unconscious life in the way of origin are the
reflexes."
Generalization of classical studies Sechenov was his work "Reflexes of the Brain"
(1863), which Pavlov called the "brilliant stroke of Russian scientific thought."
The tipping point is associated with the activities of Ivan Petrovich Pavlov (18491936) - creator of the theory of higher nervous activity, the founder of the largest
modern physiological school, pioneer methods of research in physiology.
Pavlov's research into the physiology of the cardiovascular and digestive systems
and higher levels of the central nervous system are classical.
In 1897 came the publication of his "Lectures on the principal digestive glands,
which were the generalization of research on the digestive system - practically a
newly created section of physiology.
Proceeding from the thesis "for the naturalist - all in the method of" Pavlov put into
practice the physiological studies of chronic experimental method by which it
became possible to study holistic, apparently healthy animals.
Experiments on the "chronically operated" animals were physiologists and to
Pavlov. However, they were not full, either by intention or by the method of
execution. Thus, the method of isolation of "the small ventricle, proposed by R.
Heidenhain (Heidenhain, Rudolf Peter Heinrich, 1834-1897), depriving an isolated
area of innervation. The method of chronic experiment, developed by Pavlov,
allowed him to prove experimentally nervism principle - the idea of the crucial role
of the nervous system in regulating the functional state and activities of all organs
and body systems.
Activities of Pavlov and created the scientific school was the era in the
development of physiology.
Development of physiology at the present stage
Together with the anatomy physiology is the main section of biology.
Modern physiology is a complex combination of general and specific scientific
disciplines, such as: general physiology, the physiology of human normal and
pathological, age, physiology, animal physiology, psychophysiology, and others
Subject and tasks of physiology
Physiology studies the vital processes occurring in the body at all structural levels:
cell, tissue, organ, system, hardware and organism. It is closely associated with the
disciplines of the morphological profile: anatomy, cytology, histology,
embryology, as the structure and function are mutually condition each other.
Physiol widely used data of biochemistry and biophysics to study the functional
changes occurring in the body, and the mechanism of their regulation. Physiology
is also based on general biology and evolutionary theory as a basis for
understanding the general patterns.
• Physiology was long and complicated path of development, which includes 7
periods (see a lecture on anatomy). As she emerged from the anatomy of the needs
of medicine, is gradually expanding its practical value to other sciences:
philosophy, pedagogy and psychology.
Initial ideas about bodily functions were formulated by physicians and scientists of
ancient Greece (Aristotle, Hippocrates), Ancient Rome (Galen), from Ancient
China (Huang, Bian Qiao), Ancient India and other countries. The study of body
composition conducted simultaneously with the research functions of the body.
Methods of Physiology
Physiology - this is an experimental science. It uses two basic methods:
observation and experiment.
Observation - the basic method of learning about and used in any scientific study.
Its disadvantage is the passivity of the researcher who can find only the outward
aspect of the phenomenon, for example - work (function) of the body. The
mechanism of regulation of the body can be determined only empirically.
The experiment allows the researcher to create certain conditions in which clarified
the quantitative and qualitative characteristics of the sludge that phenomenon.
The experiment can be acute or chronic. Acute experience (vivisection) allows in a
short time to study any regulatory mechanism, triggered in extreme situations for
the test organism. Chronic experiment allows for a long time to investigate the
mechanisms of regulation in the normal interaction of organism and environment.
In animal experiments using surgical techniques - extirpation (removal) or an
organ transplant, implantation of electrodes and sensors. Objective method is the
method of telemetry, capable of detecting the parameters of the process or
phenomenon from a distance.
Experimental studies in recent years carried out using sophisticated optical,
electronic, electronic equipment, allowing simultaneously explore dozens of
functions, their change in the interaction, ie complex.
Processing of the resulting data set is using the methods of mathematical statistics
and computer technology.
Illustrative material: L-OM1-1
REFERENCES:
Main:
1. Human Physiology, VM Pokrovsky., GF Korotko, M., 2004.
2. Guide to practical exercises on normal physiology. KV Sudakov, AV Kotov, M.,
2002.
3. Guidance on general and clinical physiology. V. Filimonov, MIA, 2002, 957 p.
4. Normal physiology, ed. KV Sudakov, M., 2000.
5. Aghajanian, NA, Tel LZ, Tsirkin VI, Chesnakova SA Physiology
rights. St. Petersburg, Sotis, 2000, 528 pp.
More:
1. VI Skok and MF Shuba. Neuromuscular physiology. Kiev, ed. "Highest School.
1986., 223s.
2. Nozdrachev AD, Bazhenov, Yu.I. etc. Beginning physiology. A textbook for art.
Universities. 2001.
3. Pokrovsky and others Human physiology. Textbook. In 2 vols. 1997.
4. Practical classes on "Human and animal physiology." (Iseman, RI, Dyukarev IA,
etc.) Novosibirsk. Siberian University Press. 2002. 98.
5. Students' individual work on "Human and Animal Physiology" by computer.
(Iseman, RI, Chang-Yushkov NK) Guidelines. Novosibirsk, 1988.
6. "Fundamentals of human physiology," 1 and Volume 2, BI Tkachenko, St.
Petersburg, 1994.
7. Atlas of the normal physiology of AV Korobkov, SA Chesnokov, Moscow,
High School, 1987.
8. 3. Iseman, RI, AD Gerasev, MV Iashvili. Physiology of excitable tissues.
Novosibirsk, Vol. NGPU, 1999., 125.
9. Alexandrov YI and other basics of Psychophysiology. Moscow, Infra-M, 1998.,
431s.
10. Anatomy, physiology and hygiene in tables and diagrams. Manual. 1991.
11. Handbook of physiological and laboratory parameters of healthy humans. AA
Utepbergenov, 1995.
12. Human Physiology. Ed. M. Pokrovsky, GF Korotko, in two volumes, Moscow,
2001, 368 pp.
Test questions (feedback):
1. Name the famous Kazakh scientists who have made a great contribution to the
development of national and global physiology
2. What methods of studying the physiology of uses?
3. The role of IP Pavlov in development of physiology
4. Name the features of the development of physiology at the present stage
JS MEDICAL UNIVERSITY ASTANA
Department of Physiology
LECTURE № 2.
Lecture theme: The main principles of formation and regulation of physiological
functions.
Purpose: To provide knowledge about the systemic organization of human
functions, form an idea about the mechanisms that characterize self-renewal, selfreproduction, self-control, learn to understand the processes of systemic
organization of physiological functions. Inculcate the skills of physiological
thinking.
Abstracts of lectures:
Function is a specific activity of cells, tissues and organs. For example, the
function of muscle is reduced, glands - secretion, neurons - the generation and
conduction of impulses. Due to changes in the functions the body adapts to
changes in living conditions.
All functions can be divided into:
1) Somatic (animals), which are implemented through the activities of skeletal
muscles innervated by the SNA;
2) vegetative (plant) that are associated with metabolism, growth and reproduction.
They are implemented at the expense of the internal organs innervated by ANS.
Physiological act - a complex process that is carried out with the participation of
various body systems (physiological acts breath, digestion, extraction, respiration,
etc.). For example, the physiological act of digestion involves the excitation of
sensory divisions of the CNS (visual, olfactory, gustatory, tactile), motor centers
(extraction, processing and cooking), the secretory apparatus of the gastrointestinal
tract (digestive juices), smooth muscles of the digestive tract (motility, peristalsis) ,
and intestinal epithelia (absorption). Thus, the act of digestion provided a
manifestation of complex and multiple functions at the cellular, tissue, organ and
system levels, which are included in the functional system (Fuss) and provide
useful outcomes.
The process of physiological regulation is the basis of self-gratification needs of a
living organism. Needs are met through the activities of control systems - the
nervous and endocrine.
To meet their needs in terms of changes of the environment the body needs:
1. set specific tasks;
2. achieve the intended result.
According to the teachings Anokhin, it is a useful result is a factor in determining
the behavior and functional system (Fuss). Fuss is formed as a group of
interconnected neurons that provide useful outcomes. The task of the Fuss is
identification and evaluation of results.
Fuse components are:
1 - a useful result,
2 - receptors
3 - the nerve center,
4 - actuators
5 - ways of feedback messages result of the action.
Reflex principle of the CNS.
Reflex - a reaction of the organism to changes in external or internal
environment, carried out by means of the CNS in response to stimulation of
receptors. Types of reflexes:
- The biological significance: food, defense, sex,
tentative, postural-tonic, and locomotor.
- Depending on the location of receptors: eksteroretseptivnye
(Receptors of the environment), vistseroretseptory (interoreceptors) - in
response to stimulation of receptors of the internal organs and blood vessels,
proprioceptors - in response to stimulation of receptors of skeletal muscles,
joints and tendons.
- The components of the reflex arc: monosynaptic and polysynaptic.
- The departments of the central nervous system: spinal, bulbar, mesencephalic,
diencephalic, cortical.
- Somatic and autonomic.
- The nature of the response: motor (motor), secretory, vasomotor and other
autonomic.
- The duration of response: phasic and tonic.
- The reflections of the whole organism: the unconditional and conditional.
The clinic investigate tendon and skin reflexes: knee,
ankle, plantar, abdominal, and others, as well as sucking, corneal, pupillary. In
certain diseases appear pathological reflexes (Babinski, Rossolimo, hobotkovy,
etc.).
Greater role in the study of reflex activity have Descartes, I. Prochazka, Sechenov,
Sherrington, Pavlov.
Reflex arc.
The structure of the reflex arc consists of the simplest (monosynaptic) variant
receptive and effector neurons. More frequently, there is
and an intermediate of neurons. This entire path is
title of the reflex arc. It consists of:
- Receivable receptors (reflexogenic zone);
- Afferent fibers;
- Sensitive, intercalary and effector neurons;
- Efferent fibers;
- The executive body.
Reflex tonus of the nerve centers.
Maintained constant sparse afferent impulses or humoral factors and determines
the tone of controlled body (muscle, etc.). Turning off the afferent implies falling
tone as the nerve center, and managed body (experience Bronzhesta). Particularly
important tonic effect of an oblong, medium-and intermediate brain (the reticular
formation).
In the simplest single-celled animals a single cell carries out a variety of functions.
Complication of the same organism in the process of evolution has led to the
separation of the functions of different cells - their specialty. To manage such
complex multicellular systems have been enough of an ancient method - transfer of
substances regulating vital functions of body fluids.
Regulation of various functions in the highly organized animals and humans in two
ways: humoral (Latin humor - fluid) - through blood, lymph and tissue fluid, and
nervous.
Possibility of humoral regulation of functions are limited by the fact that it acts
relatively slowly and can not provide immediate responses of the body (fast
motion, instant reaction to the extra stimuli). In addition, the humoral going
through extensive involvement of various organs and tissues in the reaction (on the
principle of "Everyone, everyone, everyone!"). In contrast, with the help of the
nervous system allows fast and precise control of various
Divisions of the whole organism, message delivery to the exact destination. Both
of these mechanisms are closely related, but a leading role in the regulation of
functions plays the nervous system.
In the regulation of the functional state of organs and tissues involved special
agents, neuropeptides, allocated by the pituitary gland, endocrine and nerve cells in
the brain and spinal cord. Currently there are about hundreds of similar substances,
which are fragments of proteins and without causing themselves excitation of cells,
can dramatically alter their functional state. They affect sleep, learning and
memory, muscle tone (in particular, within the asymmetry), cause extensive
immobilization or muscle cramps, have analgesic and narcotic effect. It was found
that the concentration of neuropeptides in the blood plasma of athletes may not
exceed the average untrained person 6-8 times, increasing the efficiency of
competitive activity. In conditions of excessive training sessions is the depletion of
neuropeptides and frustrating adaptation of the athlete to physical loads.
Illustrative material: L-OM1-2
REFERENCES:
Main:
1. Human Physiology, VM Pokrovsky., GF Korotko, M., 2004.
2. Guide to practical exercises on normal physiology. KV Sudakov, AV Kotov, M.,
2002.
3. Guidance on general and clinical physiology. V. Filimonov, MIA, 2002, 957 p.
4. Normal physiology, ed. KV Sudakov, M., 2000.
5. Aghajanian, NA, Tel LZ, Tsirkin VI, Chesnakova SA Physiology
rights. St. Petersburg, Sotis, 2000, 528 pp.
More:
1. VI Skok and MF Shuba. Neuromuscular physiology. Kiev, ed. "Highest School.
1986., 223s.
2. Atlas of the normal physiology of AV Korobkov, SA Chesnokov, Moscow,
High School, 1987.
3. Handbook of physiological and laboratory parameters of healthy humans. AA
Utepbergenov, 1995.
4. Human Physiology. Ed. M. Pokrovsky, GF Korotko, in two volumes, Moscow,
2001, 368 pp.
5. Practical classes on "Human and animal physiology." (Iseman, RI, Dyukarev IA,
etc.) Novosibirsk. Siberian University Press. 2002. 98.
6. Pribram K. Languages of the brain. Moscow, Progress, 1975., 464s.
7. Students' individual work on "Human and Animal Physiology" by computer.
(Iseman, RI, Chang-Yushkov NK) Guidelines. Novosibirsk, 1988.
8. Anatomy, physiology and hygiene in tables and diagrams. Manual. 1991.
Test questions (feedback):
1. What is called acceptor result of the action
2. What is the meaning of the afferent synthesis
3. What is the role of afferent feedback
4. What happens when you do not match the real outcome with ARD?
5. What is a reflex?
6. Call the main elements of the reflex arc
7. What is the meaning of the interaction of reflexes?
JS MEDICAL UNIVERSITY ASTANA
Department of Physiology
Lecture № 3.
Lecture theme: Initiation. Laws stimulation of excitable tissues.
Purpose: To provide knowledge about the features of excitable structures, learn to
understand the role of the neuron as an integrative unity of the body, to teach to
explain the mechanism of muscle contraction, to be able to sketch the main types
of muscle contraction and the mechanism of the synapse.
Abstracts of lectures:
The human body has a pronounced ability to adapt to constantly changing
environmental conditions. The basis of adaptive reactions of the organism is a
universal property of living tissue - irritability - the ability to respond to the action
of irritating factors changes the structural and functional properties. Irritability
have all the tissues of animals and plant organisms.
In the evolution of a gradual differentiation of tissues, performing adaptive
activities of the organism. Irritability of the tissue has reached its highest
development, and transformed into a new property - excitability. It is defined as the
ability of tissues to respond to stimulation of specialized response - excitement.
Arousal - is a complex biological process that is characterized by specific changes
in metabolic processes, heat generation, temporary depolarization of cell
membranes and is manifested specialized reaction tissue (muscle contraction,
gland secretion separation, etc.). Excitability have the nerve, muscle and secretory
tissues, they combine the concept of "excitable tissue. Excitability of the different
tissues varied.
Measure of excitability is the threshold of irritation - the minimum strength of
stimulus that can cause excitement. Less powerful subliminal stimuli are called,
and stronger --threshold. Stimulus of a living cell can be any change in the external
or internal environment, if it is large enough, there was fast enough and lasts long
enough.
Classification of stimuli. All the stimuli by their nature can be divided into three
groups:
physical (mechanical, thermal, sound, lighting, electrical);
chemicals (alkalis, acids, hormones, metabolic products, etc.);
physico-chemical (change of osmotic pressure, pH, ionic composition, etc.).
By the degree of adaptability of biological structures in their perception of the
stimuli were divided into adequate and inadequate.
Called adequate stimuli for the perception of biological structure which is specially
adapted to the process of evolution. For example, an adequate stimulus for
photoreceptor is visible light, for the baroreceptors - the change in pressure, for
skeletal muscle - a nerve impulse, etc.
Inadequate are those stimuli which act on the structure, not specifically adapted to
their perception. For example, an adequate stimulus for skeletal muscle is the nerve
impulse, but the muscle can be excited, and when exposed to electric current,
mechanical shock, etc. All of these stimuli to skeletal muscles are inadequate and
their threshold power of hundreds or more times the threshold force of adequate
stimulus.
Laws stimulation of excitable tissues.
Laws stimulation reflect a relationship between the stimulus and the response of
excitable tissue. By the laws of irritation are: the law of force, the law of "all or
nothing" law of accommodation (Du Bois-Reymond), the law of force-time
(strength-duration), the law of polar action of direct current, the law of
physiological galvanotonus.
The law of force: the greater the force stimulus, the greater the response. In
accordance with this Act, operate complex structures, such as skeletal muscle. The
amplitude of contractions from the minimum (threshold) values gradually increase
with the strength of the stimulus to submaximal and maximal values. This is due to
the fact that skeletal muscle consists of many muscle fibers with different
excitability. Therefore, the threshold stimuli are responsible only those muscle
fibers, which have the highest excitability, the amplitude of muscle contraction in
this case is minimal. With increasing strength of the stimulus in the reaction
involved more and more muscle fibers and the amplitude of muscle contraction
increases all the time. When the reaction involving all the muscle fibers that make
up this muscle, a further increase in strength of the stimulus does not increase the
amplitude of contraction.
The law "all or nothing": a threshold stimuli do not cause the response ("nothing"),
on the threshold stimuli arises maximum response ("all"). By law, an "all or
nothing" cut the heart muscle and single muscle fiber. The law "all or nothing" is
not absolute. First, the stimuli of subthreshold strength does not appear visible
reaction, but there are changes in the tissue membrane resting potential in the form
of a local excitation (local response). Secondly, the heart muscle, stretched blood,
filling her heart chambers, reacts according to the law "all or nothing", but the
amplitude of its reduction will be greater than the reduction of the heart muscle is
not stretched blood.
Law irritation DuBois-Reymond (accommodation): irritant effect of direct current
depends not only on the magnitude of the current strength or density, but also on
the rate of current rise time. Under the action of slowly rising stimulus, arousal
does not occur, since there is adaptation of excitable tissues to the action of this
stimulus is termed accommodation. Accommodation due to the fact that the action
of slowly rising stimulus in the membrane of excitable tissue is an increase in the
critical level of depolarization. By reducing the rate of increase of strength of the
stimulus to a certain minimum value of the action potential does not arise. The
reason is that membrane depolarization is the trigger stimulus to the beginning of
two processes: a fast, leading to an increase in sodium permeability, and thus gives
rise to an action potential, and slow, leading to the inactivation of sodium
permeability, and as a consequence - the end of the action potential. With the rapid
growth drivers of the sodium permeability of time to reach significant size before
you come inactivation of sodium permeability. In slow current rise to the
foreground the processes of inactivation, leading to an increase in the threshold or
eliminate the ability to generate PD at all.
The law of force-length: irritating DC depends not only on its magnitude but also
on the time within which it operates. The more current, the less time he must act
for the occurrence of arousal.
Study the dependence of strength-duration showed that the latter has a hyperbolic
character (Fig. 3). From this it follows that the current below a certain minimum
value does not cause agitation, as if he had not long to act, and the shorter pulses,
the less annoying ability they have. The reason for such 'dependence is the
membrane capacitance. Very "short" the currents simply do not have time to
defuse this capacity to a critical level of depolarization. The minimum amount of
current that can cause excitement for unlimited duration of its effect, called
rheobase. rheobase, and causes the excitation is called a useful time.
Due to the fact that the definition of this time is difficult, introduced the concept of
chronaxie - the minimum time during which a current equal to two rheobase, must
act on the fabric to cause a backlash. Determination of chronaxie - hronaksimet
Darius - finds application in the clinic. Electric current applied to the muscle,
passes through the muscle and nerve fibers and their endings are in this muscle.
Since the chronaxie of nerve fibers significantly lower chronaxie of muscle fibers,
then the study of muscle chronaxie almost get chronaxia nerve fibers. If the nerve
is damaged or the death of the spinal cord motoneurons (this occurs when
polimielite and some other diseases), then a degeneration of nerve fibers and then
determined chronaxie have muscle fibers, which is larger than the nerve fibers.
Law of the polar DC: for the closure of the current excitation occurs under the
cathode, and on opening - at the anode. The passage of direct electric current
through a nerve or muscle fiber causes a change in membrane resting potential.
Thus, in the annex to the excitable tissue of the cathode the positive potential on
the outer side of the membrane decreases, there is depolarization that quickly
reaches a critical level and causes excitement. In the same application to the anode
a positive voltage on the outer side of the membrane increases, there is
hyperpolarization of the membrane and the excitement is not there. But it is under
the anode the critical level of depolarization shifts to the level of the resting
potential. Therefore, by opening circuit current hyperpolarization of the membrane
disappears, and the resting potential, returning to its initial value, reaches a critical
level occurs shifted excitation.
Law physiological galvanotonus: the action of direct current to tissue is
accompanied by a change in its excitability. When passing a direct current through
a nerve or muscle stimulation thresholds under the cathode and adjacent areas is
reduced because of depolarization - excitability increases. In the application the
anode is an increase in the threshold of stimulation, ie, the decrease in excitability
due to membrane hyperpolarization. These changes in excitability at the cathode
and anode were called galvanotonus (electrotonic changes in excitability). Increase
in excitability at the cathode is called katelektroton, and the decrease in excitability
at the anode - anelektroton.
With a further step the DC initial increase in excitability at the cathode is replaced
by its decrease, is developing the so-called katodick depression. An initial decrease
in excitability is under the anode is replaced by its increase - anode exaltation. In
the field of application of the cathode is the inactivation of sodium channels, while
at the anode of a reduction in potassium permeability and the weakening of the
initial inactivation of sodium permeability.
Illustrative material: L-OM1-3
REFERENCES:
Main:
1. Human Physiology, VM Pokrovsky., GF Korotko, M., 2004.
2. Guide to practical exercises on normal physiology. KV Sudakov, AV Kotov, M.,
2002.
3. Guidance on general and clinical physiology. V. Filimonov, MIA, 2002, 957 p.
4. Normal physiology, ed. KV Sudakov, M., 2000.
5. Aghajanian, NA, Tel LZ, Tsirkin VI, Chesnakova SA Physiology
rights. St. Petersburg, Sotis, 2000, 528 pp.
More:
1. Human Physiology. Ed. M. Pokrovsky, GF Korotko, in two volumes, Moscow,
2001, 368 pp.
2. "Fundamentals of human physiology," 1 and Volume 2, BI Tkachenko, St.
Petersburg, 1994.
3. Atlas of the normal physiology of AV Korobkov, SA Chesnokov, Moscow,
High School, 1987.
4. Iseman, RI, AD Gerasev, MV Iashvili. Physiology of excitable tissues.
Novosibirsk, Vol. NGPU, 1999., 125.
5. Alexandrov YI and other basics of Psychophysiology. Moscow, Infra-M, 1998.,
431s.
6. Handbook of physiological and laboratory parameters of healthy humans. AA
Utepbergenov, 1995.
7. Nozdrachev AD, Bazhenov, Yu.I. etc. Beginning physiology. A textbook for art.
Universities. 2001.
8. Basic physiology of metabolism and endocrine system. Ouch. allowance. 1994.
9. Pokrovsky and others Human physiology. Textbook. In 2 vols. 1997.
10. Practical classes on "Human and animal physiology." (Iseman, RI, Dyukarev
IA, etc.) Novosibirsk. Siberian University Press. 2002. 98.
11. Pribram K. Languages of the brain. Moscow, Progress, 1975., 464s.
12. Students' individual work on "Human and Animal Physiology" by computer.
(Iseman, RI, Chang-Yushkov NK) Guidelines. Novosibirsk, 1988.
13. VI Skok and MF Shuba. Neuromuscular physiology. Kiev, ed. "Highest
School. 1986., 223s.
Test questions (feedback):
1. What is the threshold of stimulation?
2. What is the meaning of the law of force-time?
3. What is the chronaxie?
4. What is the difference chronaxie of productive time?
5. What stage includes parabiosis
JS MEDICAL UNIVERSITY ASTANA
Department of Physiology
LECTURE № 4.
Theme lecture: Membrane potential. Action potential. Reception.
Purpose: To formulate the idea of the basic mechanisms of cell theory, provide
knowledge about the mechanisms of transport of substances through cell
membranes and to teach graphically represent and analyze the phase of the action
potential.
Abstracts of lectures:
The nature of the excitation.
The first attempts to develop a coherent theory of "animal electricity" are
associated with the name of L. Galvani. He drew attention to the muscles of the
drug hind legs frog hanging on a brass hook, when you touch feet to the iron
railing of the balcony. Based on these observations, L. Galvani concluded that the
contraction of muscles legs due to "animal electricity," which occurs in the spinal
cord and is transmitted by metallic conductors to the muscles of legs. This
experience is now known as the first experience of Galvani.
Physicist L. Volta, repeating the first experiment of Galvani, came to the
conclusion that these phenomena can not be considered due to the presence of
"animal electricity." Current source according to A. Volta is not the spinal cord, as
I thought L. Galvani, a potential difference formed at the contact of dissimilar
metals - copper and iron. In response to objections DIG L. Galvani improved
experience, the deletion of the metals. He dissected the sciatic nerve of frog legs
along the thigh, and then sketched a nerve in leg muscle - muscle contraction
occurred. This experience is known as Galvani's second experience, or experience
without metals.
Later it was observed that muscle contraction in the second experiment of Galvani
occurs if the nerve in contact with both damaged and undamaged surfaces of the
muscle. Du Bois-Reymond was found that the damaged muscle area carries a
negative charge, and the undamaged area - yes. When throwing a nerve to a
damaged and undamaged areas of muscle a current, which irritates the nerve and
causes muscle contraction. This current was called the current of rest, or shock
damage.
Du Bois-Reymond, thus the first to show that the outer surface of the muscle is
positively charged with respect to its internal content. Consequently, at rest
between the outer and inner surfaces of the cell membrane there is the potential
difference, which was then called the membrane potential or resting membrane
potential. Its value in different cells varies from 60 to 90 mV.
Developed several theories of and maintaining the resting membrane potential. In
the years 1949-52. Hodgkin, Huxley, Katz and experimentally modified
membrane-ionic theory. According to this theory, the resting membrane potential
(WFP) is caused by unequal concentrations of sodium, potassium, calcium,
chlorine within the cell and the extracellular fluid, and also different permeability
for these ions, the surface of the cell membrane. The cytoplasm of nerve and
muscle cells contain 30-50 times more potassium ions in the 8-10 times less
sodium and 50 times less chlorine ions than the extracellular fluid. Consequently,
the resting state there is an asymmetry of concentration of ions inside the cell and
in its environment.
Cell limits the thinnest membrane - the membrane. The composition of the
membrane consists of lipids (mainly phospholipids), proteins and
mucopolysaccharides. According to the liquid-mosaic model of the membrane
consists of a bimolecular layer of phospholipids, which includes proteins. Some
proteins permeate through the membrane, while others are submerged in the thick
of it. In the membrane ion channels are formed by macromolecules of the protein
permeating the lipid layer. Membrane channels are divided into nonspecific
(leakage channels) and specific (selective, possessing the ability to only pass
certain ions). Nonspecific channels transmit different ions and are constantly open.
Specific channels open and close in response to changes in WFP. These channels
are called potentsialozavisimymi.
Potentsialozavismye selective ion channels are divided into: sodium, potassium,
calcium and chlorine. However, their selectivity is often not absolute, and the
channel name indicates only one. Ion, for which this channel is the most
permeable.
Ion channel consists of the channel (the transport part) and the gating mechanism
("gate"), which is controlled by an electric field of the membrane. In each channel,
suggest that there are two types of "gates" - the fast activation (m) and slow
inaktivatsionnyh (h). "The Gate" can be fully opened or closed. For example, the
sodium channels in a state of rest "gate" m closed, and the "gate" h - open. With a
decrease in charge of the membrane (depolarization) at the initial "gate" m and h
are open - the channel is in conducting state-Through open channels of the ions
move along the concentration and electrochemical gradient. Then inaktivatsionnye
"gates" are closed - the channel inactivation-tiviruetsya. As the recovery WFP
inaktivatsionnye "gate" opens slowly, and the activation quickly closed and the
channel returns to its original state.
Mucopolysaccharides, settling in the form of "trees" on the membrane surface,
perform receptor functions.
In a state of physiological rest the membrane of nerve fibers is 25 times more
permeable to potassium ions than sodium ions.
The polarization of the membrane at the open potassium channels and the presence
of a transmembrane concentration gradient of potassium, due primarily to the
leakage of intracellular potassium into the surrounding cell medium. The yield of
positively charged potassium ions leads to a positive charge on the outer surface of
the membrane. Organic anions - krupnomolekulyarnye compounds which carry a
negative charge, and for which the cell membrane is impermeable, attached to
these conditions, the inner surface of the membrane negative charge.
At rest, there are small streams of potassium and sodium ions (potassium than
sodium) across the membrane by their concentration gradient, which ultimately
should lead to equalization of the concentrations of these ions inside the cell and its
environment. But in living cells, it does not, as in the cell membrane there is a
specific molecular mechanism, called the sodium-potassium pump. It ensures
removal from the cell cytoplasm and the introduction of sodium ions into the
cytoplasm of potassium ions. Ion pump moves ions against their concentration
gradient, therefore, he is working with energy consumption.
Thus, the emergence and maintenance of the resting membrane potential due to the
selective permeability of cell membrane and the work of the sodium-potassium
pump. Resting membrane potential creates an electric field. The electric field of
the membrane resting potential provides a closed state of AK-tivatsionnyh "gate"
of sodium channels and the open-state inactivation tivatsionnyh "gate".
Registration of electrical potentials in nerve and muscle fiber or nerve cell showed
that the excitation is a change of WFP, there is potential for action. Influenced
razdrazhitelya.porogovoy-threshold or magnitude of cell membrane permeability
to sodium ions increases. Sodium ions rush into the cell, which leads to a decrease
in resting membrane potential - membrane depolarization (Fig. 2). At the
beginning of the depolarization is slow. When reducing the WFP to the critical
level of depolarization of the membrane permeability for sodium ions is increased
500-fold and exceeds the permeability of potassium ions by 20 times. As a result,
the penetration of sodium ions into the cytoplasm and their interactions with
anions, the potential difference across the membrane disappears, and then going on
the cell membrane charge (charge inversion) - inner surface of the membrane
becomes positively charged relative to its exterior. This excess capacity reaches
30-50 mV, then closed fast sodium channels - is the inactivation of sodium
permeability) and opens the potassium channels. Begins the process of restoring
the original level of resting membrane potential - membrane repolarization.
Action potential may be registered in two ways:
extracellular - with the help of electrodes attached to the outer surface of the cell;
intracellular - with the help of electrodes, one of which is introduced into the cell
and the other is located on its surface.
When extracellular abduction in a single cycle of excitation (action potentials)
distinguish the following phases (Fig. 2):
1. Predspayk (prepotential) - a process of slow depolarization to a critical level of
depolarization.
2. Peak potential or spike (including the period of recharging the cell membrane).
3. Negative afterpotential - from the critical level of depolarization to the initial
level of polarization of the membrane.
4. Positive afterpotential - an increase of the membrane resting potential and a
gradual return to its initial value.
When intracellular recording recorded the following states of the membrane:
local excitation, the local response (the initial membrane depolarization);
depolarization of the membrane (the ascending part of the spike, including
inversion);
repolarization of the membrane (the descending part of the action potential);
osledovaya depolarization (trace corresponds to a negative potential);
hyperpolarizing trace-function (corresponds to the positive potential of the trace).
Change in excitability when excited. With the development of an action potential is
a change of excitable tissues, and this change occurs but the phases (Fig. 2). As the
initial polarization of the membrane, which reflects the resting membrane
potential, corresponds to the initial state of excitability and, consequently, the cells
- a normal level of excitability. During predspayka excitable tissues is increased,
this phase of excitability was named the primary exaltation. During the
development predspayka resting membrane potential approaches the critical level
of depolarization and to achieve sufficient strength of the last stimulus smaller than
the threshold (a staff-line).
During the development of the spike (peak potential) is an avalanche-like flow of
sodium ions into the cell, resulting in a reload of the membrane and it loses the
ability to respond to stimuli even excitation-threshold power. This phase of
excitability was called the absolute refractory period (absolute nonexcitability). It
lasts until the end of the exchange membrane. Absolute refractoriness, ie, the total
nonexcitability membrane arises from the fact that the sodium channels at the
beginning of a fully open, and then inactivated.
After the end of phase exchange membrane excitability is gradually being restored
to its original level - the phase of relative refractoriness. She continues to restore
the charge of the membrane to a value corresponding to the critical level of
depolarization. Since this period, the resting membrane potential has not yet been
restored, the excitability of the tissue is reduced and a new excitation can occur
only when the action-threshold stimulus. Decrease the excitability of a phase of
relative refractoriness is associated with partial inactivation of sodium channels
and activation of potassium.
Illustrative material: L-OM1-4
REFERENCES:
Main:
1. Human Physiology, VM Pokrovsky., GF Korotko, M., 2004.
2. Guide to practical exercises on normal physiology. KV Sudakov, AV Kotov, M.,
2002.
3. Guidance on general and clinical physiology. V. Filimonov, MIA, 2002, 957 p.
4. Normal physiology, ed. KV Sudakov, M., 2000.
5. Aghajanian, NA, Tel LZ, Tsirkin VI, Chesnokov SA Physiology
rights. St. Petersburg, Sotis, 2000, 528 pp.
More:
13. VI Skok and MF Shuba. Neuromuscular physiology. Kiev, ed. "Highest
School. 1986., 223s.
14. 3. Iseman, RI, AD Gerasev, MV Iashvili. Physiology of excitable tissues.
Novosibirsk, Vol. NGPU, 1999., 125.
15. "Fundamentals of human physiology," 1 and Volume 2, BI Tkachenko, St.
Petersburg, 1994.
16. Nozdrachev AD, Bazhenov, Yu.I. etc. Beginning physiology. A textbook for
art. Universities. 2001.
17. Basic physiology of metabolism and endocrine system. Ouch. allowance. 1994.
18. Practical classes on "Human and animal physiology." (Iseman, RI, Dyukarev
IA, etc.) Novosibirsk. Siberian University Press. 2002. 98.
19. Students' individual work on "Human and Animal Physiology" by computer.
(Iseman, RI, Chang-Yushkov NK) Guidelines. Novosibirsk, 1988.
20. Atlas of the normal physiology of AV Korobkov, SA Chesnokov, Moscow,
High School, 1987.
21. Alexandrov YI and other basics of Psychophysiology. Moscow, Infra-M,
1998., 431s.
22. Anatomy, physiology and hygiene in tables and diagrams. Manual. 1991.
23. Handbook of physiological and laboratory parameters of healthy humans. AA
Utepbergenov, 1995.
24. Human Physiology. Ed. M. Pokrovsky, GF Korotko, in two volumes, Moscow,
2001, 368 pp.
Test questions (feedback):
1. How will the action potential with increasing concentration of potassium ions
inside the cell?
2. Which ions play a major role in the mechanism of excitation of cells?
3. List the main phase of the action potential
4. How to change the excitability of the tissue increases the critical level of
depolarization?
JS MEDICAL UNIVERSITY ASTANA
Department of Physiology
LECTURE № 5.
Lecture theme: System organization of pathways. Synaptic transmission.
Purpose: To provide knowledge about the peculiarities of the structure of
synapses, chemical and electrical transmission routes, learn to understand the role
of calcium in the mechanism of synaptic transmission, to be able mechanism of the
synapse.
Abstracts of lectures:
Physiology of Nerves and nerve fibers.
Nerve fibers (nerve cell processes) perform specialized functions - conducting
nerve impulses. In morphology nerve fibers are divided into myelin (myelin sheath
coated) and amyelinate. Nerve fibers form the nerve or nerve trunk consisting of a
large number of nerve fibers enclosed in a common connective-hull. The structure
consists of myelinated nerve fibers and amyelinate.
Nerve fibers conducting excitation from receptors in the CNS are called afferent,
and the fibers conducting excitation from the CNS to the executive bodies are
called efferent. Nerves are composed of afferent and efferent fibers.
Nerve fiber has the following physiological properties: excitability, conductivity,
lability.
Conduction of excitation along the nerve fibers is carried out according to certain
laws.
The Law of bilateral excitation of nerve fiber. Excitation of the nerve fiber extends
in both directions from its place of origin, i.e., the centripetal and centrifugal. This
can be proved if the nerve fiber lay recording electrodes at a certain distance from
each other, and between them to cause irritation. Excitation will fix the electrodes
on both sides of the place of stimulation.
Law of anatomical and physiological integrity of the nerve fibers. Conduction
of excitation in the nerve fiber is only possible if retained its anatomical and
physiological integrity. Various factors affecting the nerve fiber (drugs, cooling,
dressing, etc.) lead to a breach of the physiological integrity, ie, to violation of the
mechanisms of excitation transfer. Despite the persistence of its anatomic integrity
of conduction of excitation in these conditions is violated.
Law of the excitation of an isolated nerve fiber. As part of the nerve stimulation
to the nerve fiber is distributed in isolation, ie without passing from one fiber to
another. Isolated conduction of excitation due to the fact that the resistance of the
fluid that fills the intercellular spaces are much lower resistance of the membrane
of nerve fibers. Therefore, the main part of the current occurring between the
excited and unexcited portions of the nerve fiber, passes through the intercellular
slits, not acting on a number of nerve fibers located.
Isolated conduction of excitation is important. Nervsoderzhit large number of
nerve fibers (sensory, motor, autonomic), which innervate different in structure and
function of effectors (cells, tissues, organs). If the excitation of a nerve inside
spread from one nerve fiber to another, then the normal functioning of the organs
would have been impossible.
Nerve fibers in the velocity of conduction of excitation, the diameter of fibers-on,
the duration of different phases of the action potential and the structure adopted to
subdivide into three types: A, B and C. Type A fibers are in turn divided into
subtypes: A-alpha, A beta, A -gamma and-delta.
Fiber type and the coating myelin sheath. The thickest of them A - alpha, they
have a diameter of 12-22 microns and a high rate of excitation - 70-120 m / sec.
These fibers carry the excitement of motor nerve centers of the spinal cord to the
skeletal muscles (motor fibers) and from specific muscle receptors to the
appropriate nerve centers.
Three other groups of fibers Ting A (beta, gamma, delta) have a smaller diameter
of 8 to 1 micron and smaller velocity of conduction of excitation from 5 to 70 m /
sec. The fibers of these groups are predominantly sensitive conducting excitation
from different receptors (tactile, thermal, some pain, receptors of the internal
organs) in the CNS. The only exceptions are the gamma fiber, much of which
carries the excitement of the spinal cord cells to intrafusal muscle fibers.
For fibers of type B are myelinated preganglio-state fiber autonomic nervous
system. Their diameter - 1-3,5 m, and the rate of excitation - 3-18 m / sec.
For the type C fibers are Remak's fiber of small diameter - 0,5-2,0 mm. Velocity of
conduction of excitation in these fibers is not more than 3 m / s (0,5-3,0 m / s).
Most of the fiber type C - a postganglionic fiber sympathetic system, as well as
nerve fibers that conduct the excitation of pain receptors, thermoreceptors, and
some pressure receptors.
The mechanism of excitation of nerve fibers. The mechanism of excitation
propagation in different nerve fibers varies. According to current concepts of
excitation spread along nerve fibers is based on the ionic mechanisms generating
the action potential.
In the propagation of excitation along Remak's fiber local electric currents, which
occur between the excited site, negatively charged, and unexcited, positively
charged, causing membrane depolarization to a critical level, followed by AP
generation at the nearest point of the unexcited part of the membrane. This process
is repeated. Throughout the nerve fiber is the reproduction of the new PD at each
point of the membrane fibers. Such an excitation of call and continuous.
The presence of the myelin sheath of fibers having a high electrical resistance, as
well as sections of fiber, devoid of the shell (nodes of Ranvier) create conditions
for a new type of excitation of myelinated nerve fibers. Local electric currents arise
between neighboring nodes of Ranvier, since the membrane is excited to intercept
becomes negatively charged in relation to the neighboring unexcited interception.
These local currents depolyaryazuyut membrane unexcited interception to a critical
level and it appears PD (Fig. 4). Consequently, the excitement as it "jumps"
through the areas of nerve fiber coated with myelin, from one race to another. Such
a mechanism of excitation propagation is called saltatory or abrupt. The rate of this
method of excitation is much higher and it is more economical compared with the
continuous conduction of excitation, because the state is actively involved not the
whole membrane, but only a small tile in interceptions.
"Jumping" of the action potential through the area between the hooks is possible
because the amplitude of the PD is 5-6 times higher than the threshold necessary to
excite the neighboring interception. PD can "jump" is not just one but two
mezhperehvatnyh gap. This phenomenon can be observed with a decrease in the
excitability of neighboring interception under the influence of some
pharmacological substances, such as novocaine, cocaine, etc.
Nerve fibers have lability - the ability to reproduce a certain number of cycles of
excitation per unit time in accordance with the rhythm of the stimulus. Lability is a
measure of the maximum number of cycles of excitation, which is able to
reproduce the nerve fiber per unit of time without transforming the rhythm of
irritation. Lability determined by the duration of the peak of the action potential, ie,
the phase of absolute refractoriness. Since the duration of the absolute refrakternosti a spike potential of the nerve fiber is the shortest, the lability of its
highest. Nerve fiber is able to reproduce up to 1000 pulses per second.
Vvedenskii found that if part of the nerve subjected to alterations (ie, the effects of
the damaging agent) by, for example, poisoning or injury, the lability of such a
section is significantly reduced. Restore the original state of nerve fibers after each
action potential in the damaged area has been slow. In acting on this portion of
frequent stimuli, it is not able to reproduce the rhythm of irritation, and therefore
the impulse conduction is blocked. Such a state of low lability was named
Vvedenskii parabiosis. In the development of the state of parabiosis can mention
three, successive, phases: the egalitarian, the paradoxical, inhibitory.
In equalizing the phase adjustment value is a response to frequent and infrequent
stimuli. Under normal conditions, the functioning of the nerve fiber magnitude
response of the muscle fibers innervated by them subject to the law of force: the
rare stimuli response is smaller and frequent stimuli - more. In a paradoxical phase,
a further reduction in lability. In this case, the rare and frequent stimuli response
occurs, but the frequent stimuli, it is much less, since the frequent stimuli further
reduce lability, extending the phase of absolute refractoriness. Consequently, there
is a paradox - on the rare stimuli response than frequent.
In the braking phase of lability is reduced to such an extent that both rare and
frequent stimuli did not cause a response. In this case, the membrane of nerve
fibers depolarized and is not at the stage of repolarization, ie, not recovered its
original condition.
Parabiosis phenomenon lies at the heart of the local anesthetic drug. Effect of
anesthetic agents is also associated with a decrease in lability and a violation of the
mechanism of excitation of nerve fibers.
Parabiosis - a reversible phenomenon. If parabioticheskoe substance acts not long
after its termination nerve emerges from the state of parabiosis through the same
phases, but in reverse order.
The mechanism of development parabioticheskogo state is as follows. When
exposed to nerve fiber parabioticheskogo factor disrupted the ability to increase
membrane sodium permeability in response to stimulation. In the area of alteration
inactivation-activation of sodium channels caused by the damaging agent is added
to the inactivation caused by nerve impulses and reduces anxiety so that the
holding of the next pulse is blocked.
Synapse - a specialized structure that ensures the transmission of excitation from
one excitable structure to another. The term "synapse" is introduced Sherrington
and means "note", "connection", "zip".
Classification of synapses. Synapses can be classified into:
1) Their location and supplies the relevant structures:
• peripheral (neuromuscular, neuro-secretory, receptors tornoneyronalnye);
• Central (axo-somatic, axo-dendritic, axo-axo-regional, somato-devdritnye,
somato-somatic);
2) the sign of their actions - excitatory and inhibitory;
3) mode of transmission of signals - chemical, electrical, and mixed.
4) The mediator, through which the transmission - cholinergic, adrenergic,
serotonergic, glycineergic etc.
The structure of the synapse. All synapses have much in common, so the
structure of the synapse and the mechanism of transfer of excitation it is possible to
consider the example of the neuromuscular synapse (Fig. 7).
The synapse consists of three main elements:
• presynaptic membrane (in the neuromuscular synapse - a thickened end-plate);
• postsynaptic membrane;
• synaptic cleft.
Presynaptic membrane - is part of the membrane of nerve endings in the area of
contact with its muscle fibers. The post-napticheskaya membrane - the membrane
of the muscle fiber. Part of the postsynaptic membrane, which is located opposite
the presynaptic called subsinapticheskoy membrane. Singularity subsinapticheskoy
membrane is the presence of specific receptors that are sensitive to certain
neurotransmitters, and the presence of hemozavisimyh channels. In the
postsynaptic membrane, Brno, outside subsinapticheskoy there
potentsialozavisimye channels.
The mechanism of excitation transfer in chemical excitatory synapses. At synapses
with a chemical transfer of excitation of the transmitter using mediators
(mediators). Neurotransmitters - are chemical substances that provide the
transmission of excitation in the synapses. Mediators, depending on their nature
can be divided into several groups:
• monoamines (acetylcholine, dopamine, norepinephrine, serotonin and others);
• Amino acids (gamma-aminobutyric acid - GABA, glutamic acid, glycine, etc.);
• neuropeptides (substance P, endorphins, neurotensin, ACTH, angiotensin,
vasopressin, somatostatin, etc.). Neurotransmitter in the molecular form found in
vesicles of presynaptic thickening (synaptic plaque), where he goes:
• from the perinuclear area of the neuron using fast axo-channel transport
(aksotoka);
• due to the synthesis of a mediator, which takes place in the synaptic terminals of
the products of its decomposition;
• due to the reuptake of neurotransmitter from the synaptic cleft in an unchanged
form.
When along the axon to its terminal comes excitement, presynaptic membrane is
depolarized, which is accompanied by entering calcium ions from extracellular
fluid into the nerve ending. The incoming calcium ions activate the movement of
synaptic vesicles to the presynaptic membrane, their contact and destruction (lysis)
of their membranes with the release of neurotransmitter into the synaptic cleft. It
neurotransmitter diffuses to the sub-synaptic membrane, which are its receptors.
The interaction of neurotransmitter receptors leads to opening channels mainly for
sodium ions. This leads to depolarization of the membrane subsinapticheskoy and
the emergence of the so-called excitatory postsynaptic potential (EPSP). In the
neuromuscular synapse, the EPSP is called end-plate potential (PEP). Between
depolarized subsinapticheskoy membrane and its neighboring areas of the
postsynaptic membrane having local currents, which depolarizes the membrane.
When they depolarizes the membrane to a critical level in the postsynaptic
membrane of muscle fiber action potential occurs, which is distributed to the
muscle fiber membrane and causes it to decrease.
Physiological properties of chemical synapses. Synapses with a chemical
transfer of excitation have a number of common properties:
• Initiation of a synapse is carried out only in one direction (unilateral). This is due
to the structure of the synapse: a neurotransmitter released only from the
presynaptic thickening, and interacts with receptors subsinapticheskoy membrane;
• transfer of excitation through the synapses is slower than the nerve fiber - the
synaptic delay;
• transfer of excitation by means of special chemical messengers neurotransmitters;
• in the synapses of the transformation rate of excitation;
• synapses have low lability;
• synapses have a high fatigue;
• synapses are highly sensitive to chemicals (including a pharmacological) agents.
Electrical synapses exciting action. In addition to chemical synapses, excitation
transfer mainly in the central nervous system (CNS) occur in synapses with
electrical transmission. Excitatory electrical synapses characterized by a very
narrow synaptic cleft and a very low resistivity of contiguous pre-and postsynaptic
membranes, which ensures effective transmission of local electric currents. Low
resistance is generally associated with the presence of cross-channel crossing two
membranes, ie, going from cell to cell (gap junctions). Channels formed by protein
molecules (polumolekulami) contacting each of the membranes that connect the
complementary. This structure is easily passable for the electric current.
Scheme of excitation transfer in electrical synapse: a current caused by the
presynaptic action potential, annoying on-stsinapticheskuyu membrane, where
there EPSP and action potential.
Transverse channels unite cells not only electrically but also chemically, since they
are passable for many small molecules. Therefore, the excitatory electrical
synapses with lateral channels are formed, usually between the cells of one type
(eg, between cells of the heart muscle).
General properties of excitatory electrical synapses are:
• speed (much superior to those of chemical synapses);
• Trace the effects of weakness in the transmission of excitation (resulting in them
almost impossible summation of consecutive signals);
• High reliability of transmission of excitation.
Excitatory electrical synapses can occur under favorable conditions, and disappear
when adverse. For example, when damaged, one of the contacting cells of
electrical synapses with other cells are eliminated. This property is called
plasticity.
Electrical synapses can be one sided and two-way transfer of excitation.
Coffee inhibitory synapses. Along with the electrical synapses of the exciting
action can meet the electrical inhibitory synapses. An example of such a synapse
may serve synapse, which forms the nerve ending at the exit segment mautnerovsk
neurons in fishes. Inhibitory effect is due to the effect of the current caused action
potential presinapti-crystal membrane. Presynaptic potential causes a significant
hyperpolarization of the segment and hyperpolarizing current instantaneously
inhibits the generation of action potentials in the initial segment of axon.
In the mixed synapses of the presynaptic action potential generates a current,
which depolarizes the postsynaptic membrane of a typical chemical synapse, where
the pre-and postsynaptic membrane does not fit snugly together. Thus, these
synapses chemical transfer is necessary reinforcing mechanism.
Illustrative material: L-OM1-5
REFERENCES:
Main:
1. Human Physiology, VM Pokrovsky., GF Korotko, M., 2004.
2. Guide to practical exercises on normal physiology. KV Sudakov, AV Kotov, M.,
2002.
3. Guidance on general and clinical physiology. V. Filimonov, MIA, 2002, 957 p.
4. Normal physiology, ed. KV Sudakov, M., 2000.
5. Aghajanian, NA, Tel LZ, Tsirkin VI, Chesnakova SA Physiology
rights. St. Petersburg, Sotis, 2000, 528 pp.
More:
1. "Fundamentals of human physiology," 1 and Volume 2, BI Tkachenko, St.
Petersburg, 1994.
2. Atlas of the normal physiology of AV Korobkov, SA Chesnokov, Moscow,
High School, 1987.
3. Handbook of physiological and laboratory parameters of healthy humans. AA
Utepbergenov, 1995.
4. "Fundamentals of human physiology," 1 and Volume 2, BI Tkachenko, St.
Petersburg, 1994.
5. 2. Iseman, RI, AD Gerasev, MV Iashvili. Physiology of excitable tissues.
Novosibirsk, Vol. NGPU, 1999., 125.
6. Alexandrov YI and other basics of Psychophysiology. Moscow, Infra-M, 1998.,
431s.
7. Atlas of the normal physiology of AV Korobkov, SA Chesnokov, Moscow,
High School, 1987.
8. Handbook of physiological and laboratory parameters of healthy humans. AA
Utepbergenov, 1995.
9. Human Physiology. Ed. M. Pokrovsky, GF Korotko, in two volumes, Moscow,
2001, 368 pp.
Test questions (feedback):
1. The laws of conduction of excitation along the nerve fibers and nerves.
2. Parabiosis Vvedensky and its stage.
3. Physiological properties of synapses.
4. Transfer of excitation in the synapses.
5. Classification and properties of synapses
6. Mechanisms of transmission of excitation in the synapses.
7. What is the function of neurotransmitter of the neuromuscular synapse
JS MEDICAL UNIVERSITY ASTANA
Department of Physiology
LECTURE № 6.
Theme lecture: physiology of skeletal and smooth muscle. Muscle contraction.
Purpose: To provide knowledge about the features of excitable structures, learn to
understand the role of the neuron as an integrative unity of the body, to teach to
explain the mechanism of muscle contraction, to be able to sketch the main types
of muscle contraction and the mechanism of the synapse.
Physiological properties of muscle.
• Excitability - ability to come into a state of arousal when the stimulus.
• Conductivity - the ability to carry out agitation.
• Contractility - the ability of muscles to change its length or tension in response to
the stimulus.
• Lability - lability muscle is 200-300 Hz.
With the direct stimulation of the muscle (direct stimulation) or indirectly through
its innervating motor nerve (indirect stimulation), a single stimulus appears a
single muscular contraction in which there are three phases:
• latency - time from start of the stimulus before the response;
• the phase of contraction (shortening phase);
• relaxation phase.
Under natural conditions in skeletal muscle of the CNS come not single pulses, and
a series of pulses following one another at specific intervals, which corresponds to
long-term muscle contraction. Such prolonged contraction of the muscle that
occurs in response to rhythmic stimulation was called tetanic reduction or tetanus.
There are two types of tetanus: toothed and smooth.
If each successive excitation pulse is delivered to the muscle at a time when she is
in a phase of shortening, there is a smooth tetanus, and if the phase of relaxation the gear tetanus (Fig. 5).
The amplitude of the tetanic reduction exceeds the amplitude of single muscle
contraction. Based on this Helmholtz explained the process to reduce tetanic
simple superposition, ie, a simple summation of the amplitude of a muscle
contraction with an amplitude of the other. However, later it was shown that the
tetanus there is not a simple addition of two mechanical effects, since this amount
may be something more, something less. Vvedenskii explained this phenomenon
from the perspective of the state of excitability of the muscles, introducing the
concept of optimum and pessimum frequency of stimulation.
Optimal is called a frequency stimulation, in which each successive stimulation by
a phase of heightened excitability. Tetanus at the same time will be the maximum
amplitude - the best.
Pessimal called this frequency stimulation, in which each successive stimulation by
a phase of reduced excitability. Tetanus at the same time will be minimal in
amplitude - pessimal.
Modes of muscle contraction. Distinguish between isotonic, isometric and mixedmode muscle contraction.
When isotonic muscle contraction is a change of its length, and the voltage remains
constant. This reduction occurs when the muscle does not move the cargo. Under
natural conditions, similar to the type of isotonic contractions are muscle
contractions of the language.
When the isometric contraction the length of muscle fibers remains constant,
changing muscle tension. Such a contraction of the muscle can get when you try to
lift backbreaking loads.
In general, the body muscles are never purely isotonic or isometric, they always
have a mixed nature, ie, there is a change and length, and muscle tension. This
mode of reduction is called auksotonicheskim if muscle tension prevails, or if
auksometricheskim shortening predominates.
The mechanism of muscle contraction. Muscles consist of muscle fibers, which
consist of many thin filaments - myofibrils arranged longitudinally. Each myofibril
consists of protofibrils - filaments of contractile proteins actin and myosin.
Partitions, called 2-plates separated myofibrils and, hence, the muscle fiber in the
land - sarcomeres. In the sarcomere watching right transverse alternating light and
dark stripes. This transverse striation of myofibrils caused by a specific
arrangement of actin and myosin. In the central part of each sarcomere are free
thick filaments of myosin. At both ends of the sarcomers are thin filaments of actin
attached to the Z-plates. Myosin filaments appear in the light microscope as a
bright band (H-band) in a dark disc, which gives the birefringence, since it contains
filaments of myosin and actin and is called anisotropic, or A-disk. By both side
from A-disk are sites that contain only thin filaments of actin and appear to be
bright, since they have one called birefringence and isotropic or j-disks. By their
mid-goes dark line - Z-membrane. It is through such periodic alternation of light
and dark disks cardiac and skeletal muscle appear striated (striated) (Fig. 6).
At rest the ends of the thick and thin: yarns only slightly overlap at the level of the
A-disk. According to the theory of sliding filaments in reducing thin actin
filaments slide along the thick myosin filaments, moving between them by the
middle of the sarcomere. Sami actin and myosin filaments do not change their
length.
Sliding filament mechanism. Myosin filaments have a cross-bridges (projections)
with heads that move away from the bipolar filaments. Actin filament consists of
two twisted around each other chains (like a twisted string of beads) molecules of
actin. On actin filaments are troponin molecule, and the grooves between the actin
filament tropomyosin lie. Tropomyosin molecules alone are positioned so that
prevent the attachment of myosin cross bridges to actin filaments.
In many places, sections of the surface membrane of muscle cells deeper in the
form of tubules inside the fiber, perpendicular to its longitudinal axis, forming a
system of transverse tubules (T system). Myofibrils in parallel and perpendicular to
the transverse tubules is a system of longitudinal tubules (alpha system). Bubbles
on the ends of these tubes - terminal tank - come very close to transverse tubules,
forming with them the so-called triads. These bubbles are concentrated principal
amount of intracellular calcium.
At rest, the myosin bridge charged with energy (phosphorylated myosin), but it can
not connect to the actin filament, since between them there is a system of filaments
tropomyosin and troponin globules. When excited by PD is spreading rapidly
across the membranes of the transverse system inside the cell and causes release of
calcium ions from the alpha system. With the advent of calcium ions in the
presence of ATP changes the spatial position of the troponin, causing tropomyosin
filament is removed and open plots of actin, accession Mi-ozinovye head.
Connection head phosphorylated myosin with actin leads to a change in the bridge
position (its "bending"), resulting in the conformation of this part of the myosin
molecule, and the movement of actin filaments in a single step (for a "stroke") to
the middle of the sarcomere. Then, the disconnection of the bridge from actin.
Rhythmic attachment and detachment of myosin heads allow you to "pull" or pull
the actin filament in the middle of the sarcomere.
In the absence of re-excitation of the calcium ions are pumped out of the calcium
pump protofibrillyarnogo space in the system of sarcoplasmic reticulum. This leads
to a decrease in calcium ion concentration and detaching it from troponin. The
result is that tropomyosin is returned to its original location and re-blocking the
active sites of actin. However, there is phosphorylation of myosin by ATP, which
not only charges the system for further work, but also facilitates the temporary
uncoupling of filaments. Lengthening (relaxation) muscle after its reduction is a
passive process, since actin and myosin filaments slide easily in the opposite
direction by the forces of elasticity of muscle fibers and muscle, as well as the
forces stretching the muscles antagonists.
Smooth muscle. Smooth muscle, forming the muscle layers of the walls of the
stomach, intestines, ureters, bronchi, blood vessels and other hollow internal
organs, are constructed from single-spindle-shaped muscle cells. Individual cells in
smooth muscles functionally linked low-resistance electrical contacts-mi - Nexus.
Through these contacts, action potentials and slow waves of depolarization
propagate freely from one muscle fiber to another. Therefore, despite the fact that
the motor nerve endings are located on a small number of muscle fibers, due to
unhindered spread of excitation from one fiber to another in reaction involves the
entire muscle. Therefore, smooth muscles are not the morphological and functional
syncytium.
Feature of smooth muscles is their ability to carry out the relatively slow motion
and prolonged tonic contraction. Slow with rhythmic character, reduce the smooth
muscle of the stomach, intestines, ureters and other organs of the movement
provide the content of these bodies. Long-term tonic contraction of smooth muscle
is particularly well expressed in the sphincter of hollow organs, which prevents the
contents of these organs.
Smooth muscle walls of blood vessels, especially arteries and arterioles, are also in
a constant state of tonic contraction. Change in muscle tone of the walls of blood
vessels affects the value of their lumen, and consequently the level of blood
pressure and circulatory organs.
An important property of smooth muscle is its plasticity, ie, the ability to maintain
assigned to them under tension length. Skeletal muscle normally has little
plasticity. These differences are easily observed in slow tensile smooth and skeletal
muscle. When removing the tensile load fast skeletal muscle is shortened, and the
smooth is stretched. High plasticity of smooth muscle is important for normal
functioning of hollow organs. Due to the high plasticity of smooth muscle can be
completely relaxed in a shorter, and in the stretched state. For example, the
plasticity of bladder filling as it prevents excessive increase of pressure inside it.
Strong and dramatic tension of smooth muscles causing their decline. The latter is
due to the increasing tensile depolarization of the cells, causing smooth muscle
automaticity. Reduction induced by stretching, plays an important role in
autoregulation of the tone of blood vessels, and also provides an involuntary
(automatic) emptying overflowing bladder in cases where the nervous control is
absent as a result of spinal cord injury.
In smooth muscles twitch lasts a few seconds. Tetanic reduction occurs at a low
frequency of fusion of single rate and a low frequency accompanying PD.
4. Illustrative material: L-OM1-6
REFERENCES:
Main:
1. Human Physiology, VM Pokrovsky., GF Korotko, M., 2004.
2. Guide to practical exercises on normal physiology. KV Sudakov, AV Kotov, M.,
2002.
3. Guidance on general and clinical physiology. V. Filimonov, MIA, 2002, 957 p.
4. Normal physiology, ed. KV Sudakov, M., 2000.
5. Aghajanian, NA, Tel LZ, Tsirkin VI, Chesnakova SA Physiology
rights. St. Petersburg, Sotis, 2000, 528 pp.
More:
10. "Fundamentals of human physiology," 1 and Volume 2, BI Tkachenko, St.
Petersburg, 1994.
11. Atlas of the normal physiology of AV Korobkov, SA Chesnokov, Moscow,
High School, 1987.
12. Handbook of physiological and laboratory parameters of healthy humans. AA
Utepbergenov, 1995.
13. "Fundamentals of human physiology," 1 and Volume 2, BI Tkachenko, St.
Petersburg, 1994.
14. 2. Iseman, RI, AD Gerasev, MV Iashvili. Physiology of excitable tissues.
Novosibirsk, Vol. NGPU, 1999., 125.
15. Alexandrov YI and other basics of Psychophysiology. Moscow, Infra-M,
1998., 431s.
16. Atlas of the normal physiology of AV Korobkov, SA Chesnokov, Moscow,
High School, 1987.
17. Handbook of physiological and laboratory parameters of healthy humans. AA
Utepbergenov, 1995.
18. Human Physiology. Ed. M. Pokrovsky, GF Korotko, in two volumes, Moscow,
2001, 368 pp.
Test questions (feedback):
1. Physiological properties of skeletal muscle.
2. Types of muscle contraction. Twitch and its phases.
3. Tetanus, types, mechanism.
4. Fatigue muscle fatigue theory of isolated muscle and whole body.
JS MEDICAL UNIVERSITY ASTANA
Department of Physiology
LECTURE № 7.
Lecture theme: General physiology of the CNS. Mechanisms of inhibition and
excitation of nerve cells.
Purpose: To study the processes of excitation and inhibition in the central
nervous system, identify the main patterns of spread of excitation in the CNS.
Understand the mechanism of central inhibition and learn how to explain the
mechanism of various types of inhibition, to distinguish pre-from post-synaptic
inhibition.
Abstracts of lectures:
CNS central nervous system constitute the brain and spinal cord. The main
functions of the central nervous system are: 1) regulation of the activity of all
tissues and organs, and combining them into a coherent whole, and 2) providing an
organism adapt to environmental conditions (the organization of appropriate
behavior according to the needs of the organism).
Management of various functions performed by and humoral (via blood, lymph,
tissue fluid), but the nervous system plays a dominant role. In higher animals and
humans leading department of the central nervous system is the cerebral cortex,
which also manages the most complex functions in human life - mental processes
(consciousness, thinking, memory, etc.).
Physiology of nerve cells
The basic structural element of the nervous system is a nerve cell or neuron.
Through neurons transmits information from one part of the nervous system to
another, exchanging information between the nervous system and various parts of
the body. In neurons there is a complex information processing. They help form
the responses of the body (reflexes) on the external and internal stimuli.
Neurons are divided into three types: afferent, efferent and intermediate neurons.
Afferent neurons (sensory or centripetal) convey information from receptors in the
central nervous system. Bodies of these neurons are located outside the central
nervous system - in the spinal ganglia and in ganglia of the cranial nerves.
Afferent neuron has lozhnounipolyarnuyu form, ie, both his appendix out of one
pole cells. Next, the neuron is divided into long dendrites forming on the periphery
of perceiving education - receptor, and axon entering through the rear horn in the
spinal cord. By the afferent neurons also include nerve cells, axons, which are
rising the way the brain and spinal cord. Efferent neurons (centrifugal) are
associated with the transmission of descending influences from the overlying
floors of the nervous system to the underlying (eg, pyramidal neurons of the
cerebral cortex - in Fig. 42) or from the central nervous system to the working
bodies (for example, in the anterior horns of the spinal cord motor neurons are
located body or motor neurons, from which fibers go to the skeletal muscles and in
the lateral horns of the spinal cord cells are the autonomic nervous system, from
which go towards the internal organs). For efferent neurons characterized an
extensive network of dendrites and one long process - the axon. Intermediate
neurons (interneurons, or intercalary) - as a rule, the smaller cells, communication
between different (eg, afferent and efferent) neurons. They transmit nerve
influence in the horizontal direction (for example, within one segment of the spinal
cord) and vertical (eg, from one segment of the spinal cord in the other - higher or
lower-lying segments). Thanks to the many branching of the axon intermediate
neurons can simultaneously excite a large number of other neurons (eg, stellate
cells of the cortex - see Fig. 42).
Functional significance of various structural elements of the nerve cell. Various
structural elements of the neuron have their functional properties and different
physiological significance. A nerve cell consists of a body, or soma (Fig. 43), and
different processes. Numerous treelike dendrites branched processes (from the
Greek. Dendron - tree) are the inputs of neurons through which signals are sent
into the nerve cell. Output neuron is the exhaust from the cell body, axon
outgrowth (from the Greek. Axis - axis), which transmits nerve impulses on another nerve cell or a working body (muscles, glands). The shape of the nerve
cell, the length and location shoots are extremely varied and depend on the
functional purpose of the neuron.
Among neurons are found the largest cellular elements of the body. The size of
their diameter ranging from 6-7 microns (small granular cells of the cerebellum) to
70 microns (motor neurons in the brain and spinal cord). Density of their
arrangement in some parts of the central nervous system is very high. For example,
in the cerebral cortex of people per 1 mm 3 accounted for almost 40 thousand
neurons. Body and dendrites of cortical neurons were generally about half of the
cortex.
In large neurons, almost 1 / 3 - 1 / 4 the size of their body is the core. It contains a
fairly constant amount of deoxyribonucleic acid (DNA). Its constituent nucleoli are
involved in supplying the cell ribonucleic acid (RNA) and proteins. In the motor
cells in the motor activity of nucleoli were markedly increased in size. Nerve cell
plasma membrane-coated semipermeable cell membrane, which provides
regulation of the concentration of ions inside the cell and its exchange with the
environment. When excited by cell membrane permeability changes, which plays a
crucial role in the occurrence of the action potential and the transmission of nerve
impulses. Axons of many neurons are covered with myelin sheath formed by
Schwann cells, many times "wrapped" around the stem axon. However, the initial
part of the axon and the extension in place of his exit from the cell body - axonal
hillock devoid of such an envelope. Membrane of the unmyelinated parts of the
neuron - the so-called initial segment - has a high excitability.
The interior of the cell is filled with cytoplasm, which contains the nucleus and
various organelles. The cytoplasm is very rich in enzyme systems (in particular,
providing glycolysis) and protein. It pervades the network of tubules and vesicles the endoplasmic reticulum. In the cytoplasm, there are also some grains ribosomes and clusters of these grains - Nissl bodies, which are protein formation,
containing up to 50% of the RNA. This protein depot neurons, which also is the
synthesis of proteins and RNA. When excessively prolonged stimulation of nerve
cells, viral central nervous system lesions and other adverse impacts of the
magnitude of these ribosomal grains decreases sharply.
In the special apparatus of nerve cells - mitochondria oxidative processes take
place with the formation of energy-rich compounds (ATP macroergic bonds). This
power station of the neuron. In them there is a transformation of energy of
chemical bonds in a form that can be used nerve cell. Mitochondria are
concentrated in the most active parts of the cell. Their respiratory function
increases in muscular exercise. The intensity of oxidative processes in neurons
increases the higher parts of the central nervous system, especially in the cerebral
cortex. Sudden changes in mitochondria up to fracture, and hence the inhibition of
neuronal activity observed with various adverse effects (prolonged deceleration in
the central nervous system, with intense X-ray irradiation, oxygen starvation and
hypothermia).
Glial cells. In the processes of supply of nerve cells and their metabolism are also
involved surrounding neurons glial cells (glial cells or neuroglia). These cells fill in
the brains of all the space between neurons. In the cerebral cortex of approximately
5 times larger than the nerve cells. Capillaries in the central nervous system are
surrounded by dense glial cells, which cover the vessel completely, or leave a
small portion (15%) free. Outgrowths of some glial cells are located partly on the
blood vessels and partly on the neuron (see Fig. 42). It is believed that the location
of these cells between the vessel and neurons points to their role in supplying
nutrients to nerve cells from the blood. Glial cells actively participate in the
functioning of the neuron. Shown that prolonged excitation in the neuron a high
content of protein and nucleic acids is supported by glial cells, where their number
is reduced accordingly. In the process of recovery of reserves of protein and
nucleic acid first increases in glial cells, and then in the cytoplasm of the neuron.
Glial cells have the ability to move in space towards the most active neurons. This
can be seen at various afferent stimuli and by muscular exercise. For example, after
20 min. swimming rats was found to increase the number of glial cells around the
anterior horn motor neurons of the spinal cord.
Possibly glial cells are involved in conditioned reflex activity of the brain and
memory processes.
"The nervous activity generally consists of the phenomena of excitation and
inhibition. This is like two halves of one nerve activity."
IP Pavlov
The phenomenon of inhibition in the nerve centers was first discovered by IM
Sechenov in 1862, The significance of this process was examined in his book
"Reflexes of the Brain."
Braking - is an active process in the nervous system, which is called the excitation
and manifests itself as suppression of other excitement.
Inhibition plays an important role in the coordination of movements, regulation of
autonomic functions, in processes of higher nervous activity. Inhibitory processes:
1 - limit the irradiation of excitation, and concentrated it in certain parts of the
National Assembly;
2 - cut out unnecessary work at the moment bodies, coordinates their work;
3 - protect the nerve centers of the surge in work.
At the place of inhibition is:
1 - presynaptic;
2 - postsynaptically.
The shape of inhibition may be:
1 - primary;
2 - secondary.
For the occurrence of primary inhibition in the National Assembly, there are
special brake structure (inhibitory neurons and inhibitory synapses). In this case,
inhibition arises primarily, ie, without prior stimulation.
Presynaptic inhibition occurs before a synapse in axonal contacts. The basis of this
inhibition is the development of prolonged depolarization of axon terminal and the
blocking of conduction of excitation to the next neuron.
Postsynaptic inhibition associated with hyperpolarization of the postsynaptic
membrane under the influence of inhibitory neurotransmitters such as gammaaminobutyric acid (GABA). Inhibitory neurotransmitters are allocated specific
inhibitory neurons - cells Renshaw (in the spinal cord) and basket cells (in the
diencephalon).
Renshaw cells provide the development of inhibition in the motoneurons of
muscles - antagonists. They also provide a reverse (antidromic) inhibition,
protecting motor neurons from overstimulation.
Basket cells regulate the flow of excitation pulses going to the centers of the
diencephalon and cerebral cortex. They cause synchronous inhibition of an entire
group of neurons diencephalic centers, thus adjusting the rhythm of cortical
activity.
For the occurrence of secondary performance does not require special brake
structures. It arises as a result of changes in functional activity of conventional
excitable neurons. Secondary braking otherwise known pessimal. High frequency
pulses of postsynaptic membrane is strongly depolarized and becomes unable to
respond to impulses traveling to the cage.
In vivo activities of all agencies is consistent.
Harmonization of certain reflexes to perform acts of complete physiological called
coordination.
Due to the coordinated work of the nerve centers are managed motor acts (running,
walking, complex purposeful movements of practice), as well as changing the
operating mode of the respiratory, digestive, circulatory, ie autonomic functions.
These processes is achieved by adaptation of an organism to changes in living
conditions.
Illustrative material: L-OM1-7
REFERENCES:
Main:
1. Human Physiology, VM Pokrovsky., GF Korotko, M., 2004.
2. Guide to practical exercises on normal physiology. KV Sudakov, AV Kotov, M.,
2002.
3. Guidance on general and clinical physiology. V. Filimonov, MIA, 2002, 957 p.
4. Normal physiology, ed. KV Sudakov, M., 2000.
5. Aghajanian, NA, Tel LZ, Tsirkin VI, Chesnakova SA Physiology
rights. St. Petersburg, Sotis, 2000, 528 pp.
More:
9. two volumes, Moscow, 2001, 368 pp.
10. Iseman, RI, AD Gerasev, MV Iashvili. Physiology of excitable tissues.
Novosibirsk, Vol. NGPU, 1999., 125.
11. "Fundamentals of human physiology," 1 and Volume 2, BI Tkachenko, St.
Petersburg, 1994.
12. Nozdrachev AD, Bazhenov, Yu.I. etc. Beginning physiology. A textbook for
art. Universities. 2001.
13. Pokrovsky and others Human physiology. Textbook. In 2 vols. 1997.
14. Practical classes on "Human and animal physiology." (Iseman, RI, Dyukarev
IA, etc.) Novosibirsk. Siberian University Press. 2002. 98.
15. Pribram K. Languages of the brain. Moscow, Progress, 1975., 464s.
16. Students' individual work on "Human and Animal Physiology" by computer.
(Iseman, RI, Chang-Yushkov NK) Guidelines. Novosibirsk, 1988.
17. Anatomy, physiology and hygiene in tables and diagrams. Manual. 1991.
Test questions (feedback):
1. The role of the central nervous system in the integrative adaptive activity of the
organism. Excitation and inhibition in the CNS.
2. Neuron as a structural and functional unit of the CNS.
JS MEDICAL UNIVERSITY ASTANA
Department of Physiology
LECTURE № 8.
Lecture theme: Peculiarities of propagation of excitation in the CNS.
Objective: To teach to explain the mechanism of excitation in the CNS, to
generate knowledge about the basic principles of coordination of the central
nervous system and instill skills sketches and analyze the basic properties of the
nerve centers.
Abstracts of lectures:
Coordination based on a number of general regularities (principles):
1. The principle of convergence (set Sherrington) - to a single neuron receives
impulses from various parts of the nervous system. For example, in the same
neuron may converge impulses from the auditory, visual, cutaneous receptors.
2. The principle of irradiation. Excitation or inhibition, has arisen in one nerve
center can spread to the neighboring centers.
3. The principle of reciprocity (conjugacy consistent antagonism) has been studied
by Sechenov, Vvedensky, Sherrington. When excited by some of the nerve centers
of other centers of activity can be inhibited. In spinal animals stimulation of one
limb at the same time causes it to bend, but on the other side simultaneously
observed extensor reflex.
Reciprocal innervation provides a coherent group of muscles during walking,
running. If necessary vzaimosochetannye movements can vary under the control of
the brain. For example, when jumping there is a reduction of similar muscle groups
of both limbs.
4. The common final path associated with the singularity structure of the CNS. The
fact that the afferent neurons is several times larger than the efferent, so many are
flocking to the afferent impulses common to efferent pathways. Neurons form a
system of reacting like a funnel (funnel Sherrington), so many different stimuli can
cause the same motor response. Sherrington proposed to distinguish between:
a) allied reflexes (which reinforce each other, meeting on a common end-ways);
b) antagonistic reflexes (which inhibit each other).
Dominance of the finite paths of a reflex reaction is due to its importance for the
organism at the moment. In this selection of the important role played by
dominant, providing the main course of the reaction.
5. Prinitsp dominant (set Ukhtomskiy).
Dominant (Latin dominans - gospodstvvuyuschy) - is the dominant focus of
excitation in the CNS, determining the nature of the response of an organism to
stimulation.
For the dominant characteristic of sustained overexcitation of the nerve centers, the
ability of outsiders to the summation of stimuli, and inertia (after preservation of
irritation). Dominant center attracts impulses from other nerve centers, and through
them stronger. As the dominant factor in the behavior associated with the higher
nervous activity in human psychology. Dominant is a physiological basis for the
act of attention. Formation and inhibition of conditioned reflexes as related to the
dominant focus of excitation.
In the nervous system of modern ideas, there are specific and nonspecific
structures.
The specific structure of the central nervous system lie in its outer and posterior
divisions, and the nonspecific structures - in the middle sections. They differ in
structure and function.
Specific structures include all of the nerve centers and pathways conducting
afferent nerve impulses from the receptors of the body (the ascending path) and
efferent impulses to the working bodies (downward path).
Bottom-hold signal path of muscular-articular, tactile, auditory, visual, pain and
temperature sensitivity to nerve centers.
Downward path conducting impulses that provide reflex reactions of muscles and
glands (executive bodies).
Activity of specific CNS structures connected with the analysis of stimuli and the
specific nature of the responses of the body. In this work involved and non-specific
structures that alter the perception of specific stimuli and efferent activity of organs
and systems.
Non-specific structures are not connected with the analysis of any particular
sensitivity or compliance with specific reflex acts, but play an important role in the
integration of body functions. According to the location of neurons and the
abundance of their ties nonspecific structure called the reticular formation (RF).
She has activating or inhibitory effect on the work of other nerve centers. This
effect on the overlying centers called upward and to the lower centers - downward.
Illustrative material: L-OM1-8
REFERENCES:
Main:
1. Human Physiology, VM Pokrovsky., GF Korotko, M., 2004.
2. Guide to practical exercises on normal physiology. KV Sudakov, AV Kotov, M.,
2002.
3. Guidance on general and clinical physiology. V. Filimonov, MIA, 2002, 957 p.
4. Normal physiology, ed. KV Sudakov, M., 2000.
5. Aghajanian, NA, Tel LZ, Tsirkin VI, Chesnakova SA Physiology
rights. St. Petersburg, Sotis, 2000, 528 pp.
More:
1. "Fundamentals of human physiology," 1 and Volume 2, BI Tkachenko, St.
Petersburg, 1994.
2. Iseman, RI, AD Gerasev, MV Iashvili. Physiology of excitable tissues.
Novosibirsk, Vol. NGPU, 1999., 125.
3. Alexandrov YI and other basics of Psychophysiology. Moscow, Infra-M, 1998.,
431s.
4. Pribram K. Languages of the brain. Moscow, Progress, 1975., 464s.
5. Students' individual work on "Human and Animal Physiology" by computer.
(Iseman, RI, Chang-Yushkov NK) Guidelines. Novosibirsk, 1988.
6. VI Skok and MF Shuba. Neuromuscular physiology. Kiev, ed. "Highest School.
1986., 223s.
7. Handbook of physiological and laboratory parameters of healthy humans. AA
Utepbergenov, 1995.
8. Human Physiology. Ed. M. Pokrovsky, GF Korotko, in two volumes, Moscow,
2001, 368 pp.
Test questions (feedback):
1. Name the basic principles of coordination in the CNS
2. What is the meaning of the phenomenon of dominance?
3. What is the difference between the divergences of convergence?
4. What is the mechanism of synaptic potentiating?
5. What is the tone of the nerve centers?
JS MEDICAL UNIVERSITY ASTANA
Department of Physiology
LECTURE № 9.
Theme Lecture: Physiology of the autonomic nervous system
Purpose: To study the main differences between somatic and autonomic nervous
system, understand the basic mechanisms of action of mediators of the sympathetic
and parasympathetic nervous system.
Abstracts of lectures:
"Escape from the swarm like wasps action of sympathetic
nervous system, and a deep sound sleep
similar to the parasympathetic influences
on the body "Yegorov.
Nervous system of animals and humans are divided into two morphological
and functional divisions:
1 - Somatic (the animal) nervous system (systema nervosum somaticum), which
innervates skeletal muscles and sense organs, providing the perception of stimuli
and motor responses of the reaction.
2 - Vegetative (autonomic) nervous system (systema nervosum autonomicum),
which innervates the internal organs and glands, including endocrine, ensuring the
regulation of metabolism in the organs, skeletal muscle, the receptors in the central
nervous system.
VNS is the central part and peripheral part. Central parts of the VNS are nuclei
lying in the middle (III), medulla (VII, IX, X) and spinal cord. Peripheral parts of
the VNS are ganglia, nerves and their branches. Both morphology of VNS are
regulated by autonomic centers located in the hypothalamus and limbic system
structures. Supreme control over the hypothalamic centers carries the cerebral
cortex, especially the frontal and temporal divisions.
ANS activity occurs outside of consciousness, but affects the general well-being
and emotional sphere, defining the level of functional activity of the somatic
nervous system and its client agencies.
ANS regulate metabolism, growth and reproduction (trophic function), coordinates
the work of the organs and systems (adaptive function). Adaptation-trophic effect
of VNS is extended to all departments of the National Assembly, including the
cerebral cortex. This feedback makes the nervous system in the closed-loop control
system, and the whole organism is a self-regulating system of the cell to the
organism level.
The autonomic nervous system, in contrast to somatic NA, has several features:
1 - it is controlled, not controlled by the cerebral cortex;
2 - it has no proper sensory fibers, which are common to the SNA and SNC;
3 - motor autonomic fiber switch in autonomic ganglia and are composed of
preganglionic and postganglionic sites.
Depending on the location of all the ganglia are divided into:
1 - paravertebral (lying along the spine)
2 - prevertebralnye (lying at a distance from the spine in the wreath)
3 - extramural (lying near the innervated organ)
4 - intramural (behind the wall of the innervated organ).
Preganglionic fibers are white (coated with myelin), and the postganglionic fibers
of gray (amyelinate). Number of preganglionic fibers is much smaller than
postganglionic. In the ganglia of the nerve impulse propagation occurs, and this
way the contact of neurons called the cartoon (impulses are transmitted to the
organs more diffuse than in the somatic NS).
Physiological characteristics of VNS due to the structure of the fibers. Amyelinate
fibers are thin and conduct impulses at a much slower rate (1-3 m / s) than myelin
(120-130 m / s). Autonomic fibers less vobudimy and have a longer refractory
period than physical, so for the excitation of autonomic nerves need to be more
severe irritation.
VNS on their cores and nodes, as well as the character effect on the bodies divided
into:
1 - sympathetic division (pars sympathica)
2 - the parasympathetic division (pars parasympathica).
The effect of these two departments to work bodies is usually the opposite. One
department strengthens, while the other - inhibits the work of "escape from the
swarm like wasps action of sympathetic nervous system, and a deep sound sleep is
similar to parasympathetic influences on the body." Part of the bodies has only
sympathetic innervation (sweat glands, smooth muscles of the skin, adrenal
glands). Sympathetic division dominates the daytime, while awake, and
parasympathetic - in the night. Thus, ANS is one of the regulators of biological
rhythms in the body.
In organs with a dual autonomic innervation observed the interaction of
sympathetic and parasympathetic nerves in the form of concerted antagonism:
sympathetic parasympathetic division
1 - expands the pupil pupillae
2 - narrows the blood vessels dilates blood vessels
3 - speeds up and strengthens the heart slowed and weakened heart work
4 - inhibits intestinal motility increases peristalsis
5 - inhibits the secretion of the gland stimulates the secretion of glands
6 - expands the bronchial tubes narrow the bronchi
7 - speeds up and intensifies breathing slowed and weakened breathing
8 - reduces the sphincter relaxes and the bladder wall relaxes the sphincter and
reduces the bladder wall
The main parasympathetic nerve - vagus (X).
ANS has sympathetic centers in the nuclei of the lateral horns C8 - L3 spinal cord
segments. From nuclei in the anterior roots of the spinal cord are preganglionic
fibers, which are switched in sympathetic ganglia. Ganglia are two chains in front
and laterally along the spinal column and form the sympathetic trunks (truncus
syumpatiicus). They stretch from the base of the skull to the top of the coccyx,
which merge into the lower coccygeal site. Trunks are divided into cervical,
thoracic, sacral and coccyx part. In the cervical part of the 3 nodes (upper, middle,
bottom). They give postganglionic fibers to the organs of the head, neck and heart.
In the thoracic part of 10-12 knots. They give branches to the heart, lungs and
organs of the mediastinum. Of 11.5 knots depart splanchnic branches, forming the
solar (celiac) plexus (plexus coeliacus). In the loin of 5.3 knots. From these
branches go to the plexuses of the abdomen and pelvis. In Part 4 of the sacral site
who give branches to the pelvic plexus.
ANS parasympathetic has centers in the nuclei of brain stem nuclei and the sacral
spinal cord segments. The peripheral part consists of nodes and fibers III
(oculomotor), VII (facial), IX (glossopharyngeal) and X (vagus) cranial nerves,
which arise from the brain stem, and pelvic nerve.
Nucleus VII and IX of pairs of cranial nerves are part of the salivary center.
Nucleus X couples are part of the center of respiration, heart and other vital centers
of the medulla oblongata.
In the sacral segments are centers of urination, defecation and sexual functions.
In the ontogeny of the vegetative structure formed from neuroblasts situated
between krylnoy (dorsal) and the main (ventral) plates of the neural tube. Axons of
nerve cells go in the anterior roots, forming a preganglionic fiber of the SPA. From
the ganglion to the front rollers backs of migrating neuroblasts. They are on the
sides of the spine form the ganglia of sympathetic trunks. For sites sprout white
connective branches, but the nodes are gray communicating branches. Of the nodes
along the nerve fibers move toward the bodies of neuroblasts, which form
prevertebralnye, extramural and intramural ganglia.
Illustrative material: A slide-OM1-9
REFERENCES:
Main:1. Human Physiology, VM Pokrovsky., GF Korotko, M., 2004.
2. Guide to practical exercises on normal physiology. KV Sudakov, AV Kotov, M.,
2002.
3. Guidance on general and clinical physiology. V. Filimonov, MIA, 2002, 957 p.
4. Normal physiology, ed. KV Sudakov, M., 2000.
5. Aghajanian, NA, Tel LZ, Tsirkin VI, Chesnakova SA Physiology
rights. St. Petersburg, Sotis, 2000, 528 pp.
More:
1. "Fundamentals of human physiology," 1 and Volume 2, BI Tkachenko, St.
Petersburg, 1994.
2. Atlas of the normal physiology of AV Korobkov, SA Chesnokov, Moscow,
High School, 1987.
3. Alexandrov YI and other basics of Psychophysiology. Moscow, Infra-M, 1998.,
431s.
4. Anatomy, physiology and hygiene in tables and diagrams. Manual. 1991.
5. Handbook of physiological and laboratory parameters of healthy humans. AA
Utepbergenov, 1995.
6. "Fundamentals of human physiology," 1 and Volume 2, BI Tkachenko, St.
Petersburg, 1994.
7. Atlas of the normal physiology of AV Korobkov, SA Chesnokov, Moscow,
High School, 1987.
8. 3. Iseman, RI, AD Gerasev, MV Iashvili. Physiology of excitable tissues.
Novosibirsk, Vol. NGPU, 1999., 125.
9. Alexandrov YI and other basics of Psychophysiology. Moscow, Infra-M, 1998.,
431s.
10. Anatomy, physiology and hygiene in tables and diagrams. Manual. 1991.
11. Handbook of physiological and laboratory parameters of healthy humans. AA
Utepbergenov, 1995.
12. Human Physiology. Ed. M. Pokrovsky, GF Korotko, in two volumes, Moscow,
2001, 368 pp.
Test questions (feedback):
1. Physiology of the autonomic nervous system.
2. Functional features of somatic and autonomic nervous system.
3. Sympathetic, parasympathetic and metasympathetic parts of the autonomic
nervous system.
4. Higher autonomic centers.
5. Participation of the autonomic nervous system in the integration of functions in
the formation of integral behavioral acts.
6. Vegetative components of behavior.
7. Synergism and antagonism of the sympathetic and parasympathetic nervous
systems
JS MEDICAL UNIVERSITY ASTANA
Department of Physiology
Lecture № 10.
Lecture theme: Hormonal regulation of physiological functions.
Purpose: To clarify the basic mechanisms of hormone action. Provide knowledge
about the main effects of hormone changes that occur in the body when excess and
deficiency.
Abstracts of lectures:
Introduction. Basic general concepts of the endocrine system.
Historically, the importance of the endocrine glands is determined by experiments
Adolf Berthold (1849), Broun_sekara (1889), LV Soboleva (1901),
Starling and Bayliss (1902), F. Banting and Charles Best (1921), J. Muller
(1930).
Endocrine glands affect physiological processes
by hormones (the term proposed by Starling).
Variants of hormones on the mechanism of their action:
1. Hormonal (endocrine properly) - transportation through
blood to the target cell, distant.
2. Paracrine - hormone secretion into the extracellular space and
impact on the surrounding target cells.
3. Izokrinnye - impact on direct contact
target cell.
4. Nerokrinnye - act like a mediator.
5. Autocrine - action secreting cell itself to itself.
Chemically, hormones are divided into protein, steroid and amino acid derivatives.
The characteristic properties of many hormones - their high biological
Activity and types of non-specific.
Hormones are not autonomous regulators, and are closely related to
nero-humoral regulation of functions of the system.
Hormones may have on the body of:
- Metabolic effects.
- Morphogenetic effect.
- Kinetic, a trigger effect.
- Correction, normalizing effect.
- Permissive, allowing appear to other regulators.
Realize the effects on the target cell hormones can:
- Through the chemoreceptors, located outside the membrane. Effect
provided through an intermediary, which can be c-AMP, c-GMP, Ca
and other mediators activated protein kinases than active synthesis
of certain protein enzymes.
- Through chemoreceptors located intracellularly. In the cytoplasm
formed hormone-receptor complex, which penetrates into the nucleus and interacts
with chromatin, which directly affects the synthesis of proteins, enzymes.
Methods of studying the functions of the endocrine glands.
1. Removal of the glands in experimental animals and
observation related physiological changes.
2. Selective inhibition of secretory cells.
3. Introduction extracts obtained from glands.
4. Transplantation of iron removal.
5. Parabiosis of two organisms, one of whom removed gland.
6. Radioisotope method for studying the hormonal status.
7. Comparison of biological activity flowing and flowing
study of blood cancer.
8. Investigation of hormonal precursors and metabolites.
9. Biochemical methods of determining the hormone in biological medium
dah. These methods are often very complex, so the content can be measured not
only in quantitative terms but also in terms of biological activity.
10. Studies of patients with lesions of the glands.
11. Histochemical analysis of the accumulation of hormones.
12. The method of genetic engineering.
Hypothalamic-pituitary system.
The hypothalamus is higher vegetative centers, provides
regulation of all internal organs through the autonomic nervous system, endocrine
effects or neurological effects, and teaming with him in the hypothalamic-pituitary
system.
Is the site of synthesis of hormones posterior pituitary (vasopressin,
oxytocin). Is the center of the synthesis of endorphins and enkephalins.
Closely related to the pituitary gland, which modulates the function of hormone
by liberinov or statins. Known liberinov 6 and 3 statin:
- CRH - Somatostatin
- Tiroliberin - Prolaktostatin
- GnRH - Melanostatin
- Prolaktoliberin
- Somatoliberin
- Melanoliberin
In the hypothalamus are 4 neuroendocrine systems:
- Hypothalamic-ekstragipotalamnaya (endorphins, neuropeptides, neuro
Tenzin. substance P, etc.).
- Hypothalamic-adenogipofizarnuyu (neurosecretory cells aksova
basal contacts of gating vessels adenohypophysis - liberiny and statins).
- Hypothalamic-metagipofizarnuyu (neurosecretory cells producing melanoliberin
and melanostatin).
- Hypothalamic-postgipofizarnuyu (neurosecretory cells of the anterior
hypothalamus nuclei: supraoptic and paraventricular oxytocin and vasopressin).
Illustrative material: A slide-OM1-10
REFERENCES:
Main:
1. Human Physiology, VM Pokrovsky., GF Korotko, M., 2004.
2. Guide to practical exercises on normal physiology. KV Sudakov, AV Kotov, M.,
2002.
3. Guidance on general and clinical physiology. V. Filimonov, MIA, 2002, 957 p.
4. Normal physiology, ed. KV Sudakov, M., 2000.
5. Aghajanian, NA, Tel LZ, Tsirkin VI, Chesnakova SA Physiology
rights. St. Petersburg, Sotis, 2000, 528 pp.
More:
1. Basic physiology of metabolism and endocrine system. Ouch. allowance. 1994.
2. Anatomy, physiology and hygiene in tables and diagrams. Manual. 1991.
3. "Fundamentals of human physiology," 1 and Volume 2, BI Tkachenko, St.
Petersburg, 1994.
4. Atlas of the normal physiology of AV Korobkov, SA Chesnokov, Moscow,
High School, 1987.
5. Handbook of physiological and laboratory parameters of healthy humans. AA
Utepbergenov, 1995.
6. Human Physiology. Ed. M. Pokrovsky, GF Korotko, in two volumes, Moscow,
2001, 368 pp.
Test questions (feedback):
1. What is the role of humoral factors in the regulation of homeostasis.
2. List the body fluids as channels of information transmission.
3. Name the factors of neurohumoral regulation
4. As classified by the chemical nature of hormones?
5. What is a "target organ", "target cells"?
JS MEDICAL UNIVERSITY ASTANA
Department of Physiology
Lecture № 11.
Lecture theme: The metabolism and energy. Energy metabolism
Objective: To make the concept of basal metabolic rate, metabolism and energy,
learn to use practical methods of direct and indirect calorimetry, to impart skills in
determining basal metabolism.
Abstracts of lectures:
Introduction. Anabolism and catabolism
In living organisms, every process is accompanied by the transfer of energy.
Energy is defined as the ability to do work. Special branch of physics that studies
the properties and transformation of energy in various systems, is called
thermodynamics. Under the thermodynamic system is understood a set of objects,
conventionally isolated from the surrounding space.
Metabolism and energy
- A combination of physical, chemical and physiological processes of
transformation of matter and energy in living organisms, as well as metabolism and
energy between an organism and the environment. Metabolism in living organisms
is to receive from the environment of various substances, in making and using
them in the life and the allocation resulting decay products in the environment.
All occurring in the body convert energy and matter share a common name metabolism (metabolism). At the cellular level, these transformations are carried
out through complex series of reactions called metabolic pathways, and may
include thousands of different reactions.
These reactions are not random, but in strict sequence and are regulated by
multiple genetic and chemical mechanisms. Metabolism can be divided into two
related but differently directed processes: anabolism (assimilation) and catabolism
(dissimilation).
Anabolism
- A set of processes of the biosynthesis of organic matter (cell components and
other structures of the organs and tissues). It provides growth, development,
upgrading of biological structures, as well as the accumulation of energy (synthesis
macroergs). Anabolism is the chemical modification and restructuring of dietary
molecules in other more complex biological molecules. For example, the
incorporation of amino acids in cell proteins synthesized in accordance with the
instructions contained in the genetic material of the cell.
Catabolism
- A set of processes of splitting of complex molecules to simpler substances by
using some of them as substrates for biosynthesis and splitting the other side of the
end-products of metabolism with the formation of energy. By the end products of
metabolism are water (in humans approximately 350 ml per day), carbon dioxide
(about 230 ml / min), carbon monoxide (0,007 ml / min), urea (about 30 g / day),
and other substances containing nitrogen (approximately b, g / day).
Processes of anabolism and catabolism are located in the body in a state of
dynamic equilibrium. The predominance of anabolic processes over catabolic leads
to growth, accumulation of tissue mass, and the predominance of catabolic
processes leading to partial destruction of tissue structures. State of equilibrium or
nonequilibrium ratio of anabolism and catabolism depends on the age (in
childhood, anabolism predominates in adults is usually observed balance in old age
prevails catabolism), health status, carried the body of physical or psychological
and emotional burden.
Transformation and use of energy
In the process of metabolism is constantly going on transformation of energy: the
energy of complex organic compounds, arrived with food, is transformed into heat,
mechanical and electrical. People and animals get energy from the environment in
the form of potential energy contained in chemical bonds of molecules of fats,
proteins and carbohydrates. All vital processes provide energy through anaerobic
and aerobic metabolism. Generating energy without oxygen, such as glycolysis
(the splitting of glucose to lactic acid) is called anaerobic metabolism. During the
anaerobic splitting of glucose (glycolysis) or its backing substrate glycogen
(glycogenolysis) conversion of 1 mol glucose to 2 mol of lactate leads to the
formation of 2 moles of ATP.
The energy equivalent of food
The amount of energy released during the oxidation of a compound does not
depend on the number of intermediate stages of its decay, ie on whether it is
burned or oxidized in the catabolic processes. Energy stored in food is determined
in colorimetric bomb - a closed chamber, submerged in a water bath. Accurately
weighed sample is placed in this chamber filled with pure O2 and set on fire.
Number of emitted energy is determined by the change in water temperature,
ambient chamber.
In the oxidation of carbohydrates allocated 17.17 kJ / g (4,1 kcal / g), the oxidation
of 1 gram of fat yields 38.96 kJ (9.3 kcal). Storage of energy in the form of fat is
the most economical way to long-term storage of energy in the body. Proteins are
oxidized in the body is not complete.
Determining the level of metabolism
Nearly half of all energy produced by the catabolism lost as heat during the
formation of ATP. Muscle contraction - a process even less effective. About 80%
of the energy used in muscle contraction is lost as heat and only 20% is converted
into mechanical work (muscle contraction).
Direct calorimetry is a direct measurement of heat generated by the body. To this
end, an animal or person placed in a special hermetically sealed chamber, the tubes
passing through it, the water flows. To calculate heat production data are used to
the heat capacity of liquid, its volume flowing through the chamber per unit time,
and the temperature difference between entering into the camera and the resulting
liquid.
Indirect calorimetry is based on the fact that the source of energy in the body are
the oxidative processes, under which consumes oxygen and produces carbon
dioxide. Therefore, energy metabolism can be assessed by examining the exchange
of gases. The most common method of Douglas-Haldane, which for 10-15 minutes
collect exhaled air is examined person in an airtight bag of fabrics (Douglas bag).
Then determine the amount of exhaled air and the percentage of it O2 and CO2.
On the relation between the amount of carbon dioxide emissions and the amount
consumed over a given period of oxygen - the respiratory coefficient (DC) - you
can determine what substances are oxidized in the body.
DCs in the oxidation of proteins is 0.8, the oxidation of fats - 0,7, and
carbohydrates - 1,0.
Each value corresponds to a certain choleric DK equivalent of oxygen, ie the
amount of heat that is released during the oxidation of a substance per liter of
oxygen absorbed at the same time.
Basal metabolism
The intensity of energy metabolism varies greatly and depends on many factors.
Therefore, for comparison of energy costs in different individuals was introduced
conditional standard value - basal metabolic rate. Basal metabolic rate [00] - is the
minimum for the waking body energy expenditure, defined in a strictly controlled
standard conditions:
1. at a comfortable temperture (18-20 degrees);
2. in the supine position (but the examinee should not sleep);
3. in a state of emotional calm, as stress increases metabolism;
4. fasting, ie, 12 - 16 h after the last meal.
Basal metabolic rate independent of sex, age, height and body weight. The
value of basal metabolic rate on average is 1 kcal per 1 h per 1 kg of body weight.
In men, daily basal metabolic rate is approximately equal to 1700 kcal in women
basal metabolic rate of 1 kg of body weight by about 10% less than men, have
children, it more than adults, and with increasing age is gradually diminishing.
Daily consumption of energy
Daily power consumption in a healthy person is much larger than the main
exchange and consists of the following components: basal metabolism, working
allowances, ie, energy costs associated with the implementation of a work;-specific
dynamic action of food.
For people who do light work while sitting, you need 2400 - 2600 kcal per day,
with a large muscular load, required 3400 - 3600 kcal, performing heavy muscular
work - 4000-5000 kcal and above. In trained athletes during short bouts of intense
exercise, the working of exchange can be 20 times greater than the basal metabolic
rate. Oxygen consumption during exercise does not reflect the total energy
consumption, as a part of it is spent on glycolysis (anaerobic) and does not require
the cost of oxygen.
Metabolism
Metabolism begins with the nutrient in the gastrointestinal tract and air into the
lungs.
The conversion of proteins, fats, carbohydrates, minerals and water are in close
interaction with each other. In the metabolism of each of them has its own
peculiarities, and their physiological significance is different, so the exchange of
each of these substances are usually considered separately.
Exchange proteins
Proteins are used in the body primarily as a plastic material. The need for protein is
determined by its minimal amount, which will balance the loss of his body.
Proteins are in a state of continuous exchange and update. In the body of a healthy
adult of the dissolved protein per day equal to the number of newly synthesized.
Ten of the 20 amino acids (valine, leucine, isoleucine, lysine, methionine,
tryptophan, threonine, phenylalanine, arginine and histidine) in the event of
inadequate intake of food can not be synthesized in the body and are called
essential.
Other ten amino acids (nonessential) can be synthesized in the body. Of amino
acids derived from the digestive process, are synthesized for this specific form of
the organism and for each body proteins. Part of the amino acids used as energy
material, ie exposed cleavage. First they deaminated - lose the NH2 group formed
as a result of ammonia and keto acids.
If the amount of nitrogen supplied in the diet, equal to the amount of nitrogen
output from the body, the body is in nitrogen balance.
If the body receives more nitrogen than is allocated, then this indicates a positive
nitrogen balance (nitrogen retention). It arises when the mass of muscle tissue
(intense exercise), during the body's growth, pregnancy, during convalescence after
a serious illness.
A condition in which the amount of output from the body of nitrogen exceeds its
introduction into an organism, called a negative nitrogen balance. It occurs when
power is deficient in protein, when the body does not receive any of the essential
amino acids in the protein or total starvation.
Consumption must be at least 0.75 grams of protein per 1 kg of body weight per
day, for an adult healthy man weighing 70 kg is not less than 52.5 g of high-grade
protein.
Lipid metabolism
Lipids are esters of glycerol and higher fatty acids. Fatty acids are saturated and
unsaturated (containing one or more double bonds). Lipids play in the body's
energy and the plastic part. By the oxidation of fat provides around 50% of energy
needs of the adult organism. Fats serve as a reserve supply of the organism, their
reserves in humans are on average 10 - 20% of body weight. About half of them
are located in the subcutaneous fatty tissue, a significant amount deposited into the
peritoneum, perinephric tissue between muscles.
Both simple and complex lipid molecules can be synthesized in the body, with the
exception of the unsaturated linoleic, linolenic and arachidonic fatty acids, which
must come from food. These essential acids are part of the phospholipid molecules.
Butter and lard are assimilated by 93 - 98%, beef - on 80 - 94%, oil - by 86 - 90%,
margarine - at 94-98%.
Carbohydrate metabolism
Carbohydrates are the primary source of energy, and also operates in the plastic
body functions during the oxidation of glucose, intermediate products - pentoses,
which are part of nucleotides and nucleic acids. Glucose is essential for the
synthesis of certain amino acid synthesis and oxidation of lipids, polysaccharides.
The human body gets carbohydrates mainly in the form of plant starch
polysaccharide and a small amount in the form of an animal polysaccharide
glycogen. In the gastrointestinal tract by splitting them up to the level of
monosaccharides (glucose, fructose, lactose, galactose). Monosaccharides, the
main of which is glucose, are absorbed into the bloodstream and through the portal
vein enter the liver. Here, fructose and galactose are converted to glucose.
Exchange of water and minerals
Water content in the adult's body is on average 73.2 ұ3% of body weight. Water
balance in the body is supported by equal amounts of water loss and its revenues in
the body.
Daily demand for water ranges from 21 to 43 ml / kg (average 2400 ml), and is met
by revenue water by drinking (~ 1200 ml), with food (~ 900 ml) and water formed
in the body during metabolic processes ( endogenous water (300 ml). The same
amount of water appears in the urine (~ 1400 ml), faeces (100 ml) by evaporation
from the skin and respiratory tract (~ 900 ml).
Illustrative material: L-OM1-11
REFERENCES:
Main:
1. Human Physiology, VM Pokrovsky., GF Korotko, M., 2004.
2. Guide to practical exercises on normal physiology. KV Sudakov, AV Kotov, M.,
2002.
3. Guidance on general and clinical physiology. V. Filimonov, MIA, 2002, 957 p.
4. Normal physiology, ed. KV Sudakov, M., 2000.
5. Aghajanian, NA, Tel LZ, Tsirkin VI, Chesnakova SA Physiology
rights. St. Petersburg, Sotis, 2000, 528 pp.
More:
1. Physiology of digestion (a guide to the physiology). Leningrad. Science, 1974.,
762s
2. "Fundamentals of human physiology," 1 and Volume 2, BI Tkachenko, St.
Petersburg, 1994.
3. Atlas of the normal physiology of AV Korobkov, SA Chesnokov, Moscow,
High School, 1987.
4. Handbook of physiological and laboratory parameters of healthy humans. AA
Utepbergenov, 1995.
5. 4. Iseman, RI, AD Gerasev, MV Iashvili. Physiology of excitable tissues.
Novosibirsk, Vol. NGPU, 1999., 125.
6. Alexandrov YI and other basics of Psychophysiology. Moscow, Infra-M, 1998.,
431s.
7. Anatomy, physiology and hygiene in tables and diagrams. Manual. 1991.
8. Basic physiology of metabolism and endocrine system. Ouch. allowance. 1994.
9. Teppermen J., H. Teppermen. Physiology of metabolism and endocrine system.
Moscow, Mir, 1989., 648s.
10. Physiology of water-salt metabolism and kidney (the foundations of modern
physiology). St. Petersburg, 1993., 576s.
11. Human Physiology. Ed. M. Pokrovsky, GF Korotko, in two volumes, Moscow,
2001, 368 pp.
Test questions (feedback):
1. What are the methods for determining the metabolism and energy expenditure.
2. What is the main exchange.
3. The daily need for protein, fats, carbohydrates, mineral salts and vitamins.
4. What is the meaning of the law "isodynam nutrients and its shortcomings.
JS MEDICAL UNIVERSITY ASTANA
Department of Physiology
Lecture № 12.
Lecture theme: Thermoregulation.
Purpose: To study the mechanisms of physical and chemical thermoregulation,
learn the concept of the isothermal, fever and hyperthermia, be able to make the
temperature of the body schema.
Abstracts of lectures:
Chemical thermoregulation.
Chemical thermoregulation provides a level of heat production required for the
normal exercise of enzymatic processes in tissues. Development of heat in the
body is due to be done in the continuous exothermic reactions that occur in all
organs and tissues, but with varying intensity. The most intense heat generation
occurs in the muscles. Even if a man lies motionless, but with a strained muscle,
the heat generation increased by 10%. Slight physical activity leads to increased
heat generation by 50-80%, and severe muscular work - by 400-500%.
In the cold heat buildup in the muscles increases dramatically. This is because the
cooling of the body surface causes reflex reduction in chaotic muscle - muscle
tremors.
In the processes of heat generation, but the muscles play a significant role liver and
kidneys. When cooling the body heat production in the liver increases.
Physical thermoregulation.
Physical thermoregulation by changing the heat transfer body.
Heat transfer is carried out in the following ways:
• radiation (radiation);
• conducting (conduction);
• convection;
• evaporation.
Heat radiation (radiation) provides a heat transfer body its environment by means
of infrared radiation from the surface of the body. Radiation by the body gives
most of the heat. At rest and in thermal comfort due to radiation released more than
60% of the heat generated in the body.
Heat passing occurs through contact with objects, the temperature is below body
temperature. By heat passing body loses about 3% of the heat.
Convection provides heat transfer adjacent to the body of air or liquid. In the
process of convection, heat is carried away from the surface of coca flow of air or
liquid. By convection is given by the body for about 15% of the heat.
Giving the body heat is also carried by water evaporation from the skin and
mucous membranes of the respiratory tract during breathing. Evaporation of water
from the body occurs when sweat. Even under conditions of thermal comfort in the
absence of visible perspiration evaporates through the skin up to 0.5 liters of water
per day. The evaporation of 1 liter of sweat a person can lower the body
temperature of 10 ° C. By evaporation from the body is removed about 20% of the
heat. At an ambient temperature equal to or above human body temperature, when
other means of heat transfer dramatically reduced, evaporation becomes the main
way heat transfer. Impact of heat by evaporation decreases with increasing
humidity by stops completely at 100% relative humidity.
Regulation of the constancy of body temperature.
Body temperature is a constant of the body that determines the constancy of the
speed of biochemical reactions, one of the most important conditions of life of the
organism. Maintaining constant body temperature is carried out according to the
principle of self-regulation through the formation of a functional system of
thermoregulation. System-forming factor (constant) of the functional system is the
temperature of blood in the right atrium (37 C). Reflex changes in
thermoregulatory processes occur dpu stimulation of heat and cold receptors
located in the skin, the mucous membranes of the respiratory tract, internal organs,
blood vessels, in various regions of CNS (hypothalamus, reticular formation,
medulla and spinal cord, motor cortex, etc.). An exceptionally large amount of
central thermoreceptors, which respond to changes in temperature of blood in the
hypothalamus.
Located in the hypothalamus of the nuclei that make up the center of
thermoregulation, which consists, in turn, from the center of heat generation and
heat-transfer center. Center of heat generation is located in the caudal portion of
the hypothalamus. With the destruction of this brain region in the animal violated
the mechanisms of heat generation and an animal becomes unable to maintain
body temperature at lower ambient temperature, and developed hypothermia.
Center heat transfer is in the anterior hypothalamus (between the anterior
commissure and optic chiasm). With the destruction of this area as the animal loses
its ability to maintain an isothermal, with the ability to tolerate low temperatures
had preserved.
In addition to the hypothalamus in thermoregulation processes also affect other
structures of the CNS: the centers of the spinal cord, striatum, reticular formation
of the brain cortex of the brain. Of these structures are the hypothalamus, reticular
formation and spinal cord oscillatory centers have played a leading role in reflex
regulation of body temperature. For example, while reducing ambient excitation of
cold receptors comes from the afferent nerves in the heat production centers of the
hypothalamus and spinal cord oscillatory centers. Hence it is stimulation of motor
nerves to muscles, increasing their tone, and then causes muscle tremor, which
leads to a significant increase in heat generation. By autonomic nerves excitement
comes to the vessels (especially the skin) and causes a decrease in their clearance.
As a result, the surface layers of skin get less warm blood, and therefore give less
heat.
In thermoregulation participate and humoral factors, especially the thyroid
hormones (thyroxine, etc.) and the adrenal glands (adrenaline, etc.). By reducing
the ambient temperature of thyroxine and adrenaline in the blood increases. These
hormones, together with the sympathetic nervous influences enhance oxidative
processes, thereby increasing the amount of heat generated in the body. Adrenaline
also narrows the peripheral vessels, which leads to a further reduction of heat
transfer.
Thus, while reducing ambient included neuro-humoral mechanisms that lead to a
significant increase of heat generation and reduce heat loss, resulting in body
temperature in these conditions remain constant.
With increasing ambient temperature, the above processes have the opposite
character.
If a person is a long time to be under significantly high or low temperature
environment, the regulatory mechanisms by which under normal conditions is
supported by the isotherms may be insufficient. If you do not use behavioral
methods of temperature regulation, aimed at cooling or warming the body, it can
come overheating - hyperthermia - or hypothermia - hypothermia.
Hypothermia and hyperthermia
Hyperthermia
- A condition in which body temperature rises above 37 ° C. It occurs during
prolonged action of high ambient temperature, especially at high humidity. Sudden
hyperthermia, in which the body temperature reaches 40-41 ° C is accompanied by
severe general condition of the body and is called heat stroke.
Hyperthermia can occur under the influence of some endogenous factors that
heighten the processes of heat generation (thyroxine, fatty acids, etc.), as well as
under the influence of microorganisms, since the hypothalamic thermoregulatory
centers are highly sensitive to bacterial toxins.
Hypothermia
- A condition where the body temperature drops below 35 C. Hypothermia occurs
most rapidly when immersed in cold water. In this case, first observed stimulation
of the sympathetic autonomic nervous system and reflex action is limited to heat
transfer and enhanced heat production, especially due to muscle tremors. But after
a while the body temperature begins to fall all the same, this results in a state
similar to anesthesia: loss of sensitivity, the weakening of reflex reactions,
reducing the excitability of nerve centers, a sharp decrease in metabolic rate, slow
breathing, slowing of the heart function, lowering blood pressure.
Currently, artificial hypothermia with the cooling of the body to 24-28 C is used in
surgery for heart surgery and central nervous system. Hypothermia reduces
cerebral metabolism and, consequently, reduces the need for it to oxygen.
Therefore, the brain in these conditions can endure longer bleeding (instead of 3-5
minutes at normal temperature for 15-20 min at 25-28 C), and this means that
during hypothermia the body can easily move the temporary shutdown of cardiac
activity and respiratory failure.
To turn off the adaptive responses aimed at maintaining body temperature during
artificial hypothermia used drugs turning down the transmission of impulses in the
sympathetic system (ganglioplegicheskie drugs), and ceasing the transmission of
excitation from nerve to skeletal muscle (muscle relaxants). Hypothermia is
stopped by rapid warming the body.
Illustrative material: L-OM1-12
REFERENCES:
Main:
1. Human Physiology, VM Pokrovsky., GF Korotko, M., 2004.
2. Guide to practical exercises on normal physiology. KV Sudakov, AV Kotov, M.,
2002.
3. Guidance on general and clinical physiology. V. Filimonov, MIA, 2002, 957 p.
4. Normal physiology, ed. KV Sudakov, M., 2000.
5. Aghajanian, NA, Tel LZ, Tsirkin VI, Chesnakova SA Physiology
rights. St. Petersburg, Sotis, 2000, 528 pp.
More:
1. Anatomy, physiology and hygiene in tables and diagrams. Manual. 1991.
2. Basic physiology of metabolism and endocrine system. Ouch. allowance. 1994.
3. Teppermen J., H. Teppermen. Physiology of metabolism and endocrine system.
Moscow, Mir, 1989., 648s.
4. "Fundamentals of human physiology," 1 and Volume 2, BI Tkachenko, St.
Petersburg, 1994.
5. Atlas of the normal physiology of AV Korobkov, SA Chesnokov, Moscow,
High School, 1987.
6. 3. Alexandrov YI and other basics of Psychophysiology. Moscow, Infra-M,
1998., 431s.
7. Handbook of physiological and laboratory parameters of healthy humans. AA
Utepbergenov, 1995.
8. Human Physiology. Ed. M. Pokrovsky, GF Korotko, in two volumes, Moscow,
2001, 368 pp.
Test questions (feedback):
1. What is the fundamental difference between hyperthermia from fever?
2. List the types of physical thermoregulation
3. What is the temperature of the human liver?
4. In hot weather, one of two people, skinny or full will consume more fluids?
JS MEDICAL UNIVERSITY ASTANA
Department of Physiology
Lecture № 13.
Lecture theme: General physiology of analyzers.
Purpose: To give an idea of the general properties of the analyzers to clarify the
meaning of Pavlov on the analyzers to instill the ability to explain the mechanisms
of the major divisions of the analyzer, to generate research skills analyzer systems.
Abstracts of lectures:
"Any knowledge paves its way
in us through the senses - they are our masters ".
M. Montel "experience".
"Nature has endowed me with all five
feelings without the slightest damage, and
almost soverenstve.
M. Montel "experience".
Introduction. Pavlov's doctrine about analyzer
The human body constantly receives information from the external environment of
the internal organs and body parts.
Physiological apparatus, take this information is called sensory organs. There are
five senses:
1 - Body of touch (skin)
2 - organ of taste (tongue)
3 - olfactory organ (nose)
4 - the organ of vision (eyes)
5 - organ of hearing and balance (ear)
Old physiology in such a classification of pushed on a subjective criterion of
sensations (and anatomical localization criterion receptor system).
These peripheral units afferent systems represent only part of the complex
physiological structures that perceive various stimuli, convert them into nerve
impulses are conducted in accordance centers of the CNS, which provides analysis
of information. IP Pavlov naturally combines the notion of mental activity are two
mechanisms:
1 - a mechanism of conditioned reflexes,
2 - Mechanism analyzers (higher cortical structures of perception of information).
On this basis, Pavlov suggested calling the senses analyzers. Analyzer (according
to Pavlov) comprises three divisions:
I - peripheral,
II - conductor,
III - Central.
So, the senses are auxiliary devices of more complex structures of the body - the
analyzers.
According to modern scientific ideas analyzer is a private entity apparatus of
perception, in which apart from analysis carried out complex processes of
synthesis. Analysis of stimuli occurs at all levels of the analyzer.
Initial analysis occurs in the receptors that respond to specific stimuli of the
environment. More sophisticated analysis occurs in the spinal cord (spinal animal
reaction to tactile, painful stimuli).
The most sophisticated analysis is carried out in brain structures in the projection
zones of the cortex, which also occur during synthesis. In this regard, modern
physiology operates a new scientific concept - the sensory system (from the Latin
sensus - feeling, sensation).
Sensory system is capable of conducting impulses from receptors in the higher
parts of the central nervous system in several ways. The main way sensory system
consists of five parts:
1 - receptor (peripheral)
2 - sensitive neuron (in the ganglia)
3 - the second neuron (in the spinal cord)
4 - the third neuron (the thalamus)
5 - the fourth neuron (in a specific projection cortex).
These five sections constitute a particular way of sensory systems. In addition, in
the spinal cord and subcortex in parallel switching information to non-specific way
of sensory systems, leading to other divisions of the CNS (cerebellum, reticular
formation) and then in the cerebral cortex.
Receptor specific sensitivity sends impulses to your area of the cortex in specific
ways, and in other areas - for non-specific ways. As a result, in the cerebral cortex,
a complicated mosaic of excited cortical areas (sensory, association, movement)
and other parts of the brain, reflecting an analytic-synthetic activity. This activity
allows us to more fully perceive the events of the outside world, to determine the
attitude to it and respond conscious behavior. Sensory systems solve the central
philosophical problem of the relationship of being correct reflection of the outside
world in the mind of man.
Knowledge of the world always begins with the feeling that allows us to identify
specific properties and qualities of objects. Based on the experiences formed the
perception of an object or phenomenon as a whole, in the unity of all its properties
and qualities. On the basis of sensations and perceptions, and there is formed a
view that extends the capabilities of human cognition. Representation makes it
possible to reproduce the image of an object or phenomenon to influence in the
past on human consciousness.
Feelings, perceptions and ideas reflect only the outer side, and link the individual
objects and phenomena. Knowledge of the nature of the phenomena of the
processes carried out by abstract thought, which, through concepts, judgments and
inferences can reveal the nature of the phenomena, their internal communication.
The most difficult process of psychological knowledge of human personality is a
different range of interests of science of psychology. Disclosure of psychological
phenomena, acting in the form of inner feelings (sensations, thoughts, feelings) and
are inaccessible to direct observation, is due to the sensory systems.
Sensory systems can be classified into several groups.
By the nature of the stimuli:
1 - mechanical (tactile, pain, proprioceptive, vestibular sensory systems,
baroretseptivny Front visceral sensory system)
2 - chemical (gustatory, olfactory sensory system, hemoretseptivny Front visceral
sensory system)
3 - light (visual sensory system)
4 - sound (auditory sensory system)
5 - temperature (temperature sensor system).
On the environment from which perceived irritation:
1 - External (gustatory, tactile, olfactory, visual, auditory
sensory systems),
2 - internal (chemical, barostezicheskaya sensory systems).
Temperature, pain, vestibular, and proprioceptive sensory systems respond to
external and internal stimuli.
All analyzers do not operate in isolation but in close coordination with each other.
Influence of environment on the organism treated by several sensory systems that
are based on analiko-synthetic activity of the brain provide a holistic perception of
the processes or phenomena that they are adequately reflected in human
consciousness.
Peripheral (receptor) department of the analyzer
Receptor - a specialized structure, adapted for the perception of the appropriate
(adequate) stimuli of the external world or internal state.
Information processing begins with the receptor and is managed by
overlying parts of the brain (increase or decrease the sensitivity of the receptor,
"vytormazhivanie" unnecessary information, the gate mechanism of pain reception,
the adaptation of receptors).
The mechanism of excitation of receptors
Formation energy of irritation in the process of excitation in the receptor due to the
energy metabolism of receptors themselves under
influence, but not at the expense attached to them outside of energy. External
stimulus causes membrane depolarization, called the generator (receptor) potential,
which does not obey the "all or nothing" depends on the strength of the stimulus,
can add up, and not
propagates along the nerve fiber. Duration generator
capacity can be significant, at all times while
the stimulus (the potentials of the carotid sinuses may last
several hours). In the generation of receptor potential are important
ions Na 2. The influence of the external stimulus may be twofold:
- The direct effect of the stimulus on the membrane receptor.
- Start a specific chemical reaction that changes the permeability of the membrane
or the formation of a physiologically active substance or
mediator.
When the receptor potential reaches a critical value, it
raises a number of afferent impulses in the nerve fiber associated with
receptor. This pulse occurs near the receptor interception
Ranvier. The frequency of afferent impulses in the nerve fibers directly
proportional to the depolarization of the receptor, as well as the logarithm
strength of the stimulus.
Adaptation of the receptor
Adaptation of the receptor - a device to force his stimulus seen in the reduction
of sensitivity to the stimulus constant, "addiction" to him. In adapting declining
value of the generator potential and impulse frequency (experiments Adrian).
The ability to adapt is absent in vestibuloretseptorov and proprioceptors. In the
adaptation is essential adaptation-trophic effect of sympathetic nervous system, the
influence of the reticular formation, as well as quantity of functioning receptors
(functional mobility of receptors for PG Snyakinu).
Principles of information coding in the nervous system
Presumably, the transmission of information through the nerve fiber is carried
out in binary code: it is transmitted bursts, the amplitude of individual potentials
are the same, but the frequency and number of impulses in the volley vary widely.
Speed channel can be measured by the number of pulses passing through the fiber
in the second.
Some receptors (photoreceptors) may be responsible both for the appearance of
the stimulus, and at its disappearance, as well as to have a constant "background"
impulses that provides tone.
Provodnikovy Front analyzer
Conductor Division include:
- Afferent neurons and their axons. Located in the ganglia (except the
photoreceptors, where the afferent neuron is located directly on the retina).
- Neurons, located in the spinal cord, medulla and midbrain. Axons go to the
specific thalamic nuclei (specific route), the reticular formation and nonspecific
thalamic nuclei (non-specific way).
- Specific thalamic nucleus: there is but one neuron, which is involved in
processing information (except olfactory analyzer). Axons go to the cortical
division of the analyzer to the corresponding projection and associative areas.
- Non-specific path to the reticular formation, hypothalamus, nonspecific nuclei of
the thalamus.
Central (cortical), Department of the analyzer
In cortical department has appropriate projection (decoding and signal analysis)
and associative areas (aktseptsiya signal with the process of memory and
comparison with its target earlier images).
Role of cortical analyzer in decoding, analyzing information and creating an
integrative view of applying the stimulus.
Illustrative material: L-OM1-13
REFERENCES:
Main:
1. Human Physiology, VM Pokrovsky., GF Korotko, M., 2004.
2. Guide to practical exercises on normal physiology. KV Sudakov, AV Kotov, M.,
2002.
3. Guidance on general and clinical physiology. V. Filimonov, MIA, 2002, 957 p.
4. Normal physiology, ed. KV Sudakov, M., 2000.
5. Aghajanian, NA, Tel LZ, Tsirkin VI, Chesnakova SA Physiology
rights. St. Petersburg, Sotis, 2000, 528 pp.
More:
1. "Fundamentals of human physiology," 1 and Volume 2, BI Tkachenko, St.
Petersburg, 1994.
2. 2. Iseman, RI, AD Gerasev, MV Iashvili. Physiology of excitable tissues.
Novosibirsk, Vol. NGPU, 1999., 125.
3. Alexandrov YI and other basics of Psychophysiology. Moscow, Infra-M, 1998.,
431s.
4. Anatomy, physiology and hygiene in tables and diagrams. Manual. 1991.
5. Atlas of the normal physiology of AV Korobkov, SA Chesnokov, Moscow,
High School, 1987.
6. Handbook of physiological and laboratory parameters of healthy humans. AA
Utepbergenov, 1995.
7. Human Physiology. Ed. M. Pokrovsky, GF Korotko, in two volumes, Moscow,
2001, 368 pp.
Test questions (feedback):
1. What is the analyzer, according to the teachings of Pavlov
2. What are the basic units consist Analyzers
3. How is the detection of signals in the central parts of the analyzer
4. What is the function of the receptor Front analyzer?
5. How information is encoded in the analyzer?
JS MEDICAL UNIVERSITY ASTANA
Department of Physiology
LECTURE № 14.
Lecture theme: Private physiology of analyzers.
Purpose: To give an idea about the basic properties of the analyzer systems:
visual, auditory, vestibular, somatosensors, olfactory, gustatory, form study skills
analyzer systems.
Plan of lecture: visual sensory system and its auxiliary apparatus.
"Scilicet, avolsis radicibus, ut nequit ullam dispicere, ipse oculus rem, seorsum
corpore toto. - Torn from orbit and is outside the body of the eye is not able to
behold no object "
Titus Lucretius Carus.
"Inter caecos luxus rex" (Latin)
Among the blind the one-eyed - the King.
"In the country of the blind one-eyed man is a King" (English)
Visual sensory system provides the person holding the brain 90% of information
about events happening in the external environment, so it could not be
overemphasized.
Receptor cells are located in the retina of the eyeball. Impulses from the
photoreceptors to the optic nerve fibers reach the optic chiasm, where part of the
fiber goes to the opposite side. Further, visual information is carried by the optic
tract to the upper dvuholmiyu, lateral geniculate bodies and thalamus (subcortical
visual centers), and then the optic radiation in the visual cortex area of the occipital
lobes (17, 18 and 19 field Brodmann).
Anatomically eyesight (organum visus) presented by:
1. eyeball
2. Aids eye
Auxiliary apparatus includes:
1. muscles of the eyeball (7 striated muscle)
2. Protective device (eyebrows, eyelashes, eyelids, conjunctiva)
3. Lacrimal apparatus
Eyeball together with the auxiliary device is located in the cavity of the eye socket.
I. The wall of the eyeball consists of three layers:
1. cornea (optical eye opening)
2. sclera (tunica albuginea)
II. Choroid is presented:
1. iris (pigmented, with a physical hole in the center - the pupil). Iris sphincter and
dilator contains pupil (smooth muscle, regulating pupil size, depending on the
lighting).
2. Ciliary body, which contains a smooth ciliary muscle, which changes the
curvature of the lens and is attached to its equator with tsinnovoy ligament. Ciliary
muscle tension increases the curvature of the lens and shortens its focal length,
muscle relaxation reduces the curvature of the lens and extends the focal length.
Ciliary muscle - an element of the apparatus of accommodation. Accommodation the ability to clearly see objects at different distances from the eye.
3. Actually choroid (contains blood vessels that feed the structure of the eye).
III. Retin-A - photosensitive layer of the shell before the eyes of pigmented cells
in several layers of neurons of different types. The main functional cells, here are
two types of photoreceptors:
1. Sticks (receptors in black and white twilight vision) - 130 million
2. cones (color receptors daylight vision) - 7 million
These cells convert the energy of light into nerve impulses.
Nerve fiber layer (I).
Layer of ganglion cells.
Layer of bipolar cells.
Layer of horizontal and amakrinnyh cells.
Layer of rods and cones.
Pigment layer.
Behind them are horizontal and amakrinnye cells, and the next layer are bipolar
neurons that connect the rods and cones with the next layer of ganglion cells. The
axons of these cells, gathering in one place the retina (the optic disc, blind spot),
out of the eyeball in the optic nerve fibers.
Rods and cones in the retina are uneven. In the anterior part of - only sticks. In the
central fovea yellow spot - only the cones, this place is the best vision. In the
intermediate regions, there are rods and cones. In the place of exit of the optic
nerve receptor cells do not. The existence of "blind spots" can be verified by
experience Mariotte.
In the sticks contain the pigment rhodopsin, and in the cones - nodopsin. Under the
influence of light pigments are broken and this causes a chemical process in cells
of the electric potential. To restore the rhodopsin requires its components - With a
lack of vitamin A. Vitamin A in the body develops "Night blindness" (dayblindness).
"The light can be very dangerous for us when he suddenly amid the darkness
shine. Such light is unbearable eyes and vision to us without the use of blunts "
William Shakespeare
Sensitivity of the eye depends on the light. In the transition from darkness into
light comes temporary blindness. By reducing the sensitivity of the photoreceptors,
after a while the eye becomes accustomed to the light (light adaptation). In the
transition from light to darkness and blindness occurs. After some time, increases
the sensitivity of the photoreceptors and vision is restored (dark adaptation).
Consideration of subjects with both eyes is called binocular vision.
In this case, we see not two, but one subject. This is due to:
1. Reduction of the ocular axes (convergence) in consideration of nearby objects
and cultivation of the axes (divergence) when considering distant objects.
2. Perception of the image object corresponding (identical) parts of retina of right
and left eyes.
Binocular vision allows us to determine the distance to the object and its bulk
form, and also expands the angle of view to 180 degrees. If a little pressure on the
side of one eye, then the person begins to "see double" in the eyes, because in this
case, the image of an object falling on non-identical parts of the retina. This
phenomenon is called disparatsiey view.
Retina
Retin-A - photosensitive layer of the shell before the eyes of pigmented cells,
several layers of neurons of different types. The main functional cells, here are two
types of photoreceptors: rods (receptors in black and white twilight vision) and
cones (color receptors photopic vision). These cells convert the energy of light into
nerve impulses.
Rods and cones in the retina are uneven. In the anterior part of - only sticks. In the
central fovea yellow spot - only the cones, this place is the best vision. In the
intermediate regions, there are rods and cones. In the place of exit of the optic
nerve receptor cells do not.
In the sticks contain the pigment rhodopsin, and in the cones - iodopsin. Under the
influence of light pigments break down, and this causes a chemical process in cells
of the electric potential. To restore the rhodopsin requires its components - With a
lack of vitamin A. Vitamin A in the body develops "Night blindness" (dayblindness).
Impulses from the photoreceptors to the optic nerve fibers reach the optic chiasm,
where part of the fiber goes to the opposite side. Further, visual information is
carried by the optic tract to the upper dvuholmiyu, lateral geniculate bodies and
thalamus (subcortical visual centers), and then the optic radiation in the visual
cortex area of the occipital lobes (17, 18 and 19 field Brodmann).
Electrical phenomena in the retina and optic nerve
Electroretinogram: a record of electric potentials or directly from the retina or the
intact eye. When illuminated the eye to detect changes and potential of the retina of
the eyeball as a whole. We studied the Nobel Prize granite.
Action potentials in the optic nerve: first recorded in 1927 by Adrian and Mathews.
Manifested in the appearance and the frequency of impulse activity in covering his
eyes. In recent years, shown that different shapes cause a kind of action potentials
in the respective fibers.
Adaptation
In the transition from darkness into light comes temporary blindness. By reducing
the sensitivity of the photoreceptors, after a while the eye becomes accustomed to
the light (light adaptation). In the transition from light to darkness and blindness
occurs. After some time, increases the sensitivity of the photoreceptors and vision
is restored (dark adaptation).
Binocular vision
Consideration of subjects with both eyes is called binocular vision. In this case, we
see not two, but one subject. This is due to:
reduction of eye axis (convergence) when considering the close objects and
cultivation of the axes (divergence) when considering distant objects, the
perception of the image object corresponding (identical) parts of the retina of the
right and left eyes.
Color vision
Man has a color vision and can distinguish a large number of colors. There are a
number of theories of color vision.
Hering's theory proposes the existence of cones in the three hypothetical pigments:
white and black, red and green, yellow and blue.
The decay of these pigments under the influence of light can feel the white, red and
yellow. When restoring a sense of pigments is black, blue and green colors.
Three-University-Helmholtz theory according to which there are three types of
cones; perceiving red, green and blue-violet color. Summation of excitation of
these cells in the cerebral cortex gives a sense of a color within the visible
spectrum.
Violation of color vision first described by physicist John Dalton, suffer from this
pathology (1794). Color Blindness - hereditary abnormality, a recessive mutation,
but is located in the sex X chromosome, due to what can occur in men who do not
have the second X chromosome is much more common than in women, where it
requires a manifestation of homozygosity for recessive mutant lines.
Dichromatic:
- Protanopia - red-blindness,
- Deuteranopia - blindness to green
- Acyanopsia - blindness in purple and blue.
Monochromatic: achromatopsia.
We investigate the color vision by using polychromatic tables or devices
anomaloscope.
Accommodation
Adapting the eye to the clear vision of objects called raznoudalennyh
accommodation of the eye. It is performed by changing the curvature of the lens.
Changing the curvature of the lens by ciliary muscle is attached to the ciliary body
and tsinnovoy bundle and capsule that contains the lens. Tsinnovy ligaments are
always stretched, bent and the lens capsule is passed flattened. Ciliary muscles
relax while reducing cravings tsinnovyh ligaments, reduce pressure on the lens,
which is under its own elasticity increases the curvature. With age, the elasticity of
the lens decreases (presbyopia, or presbyopia).
The pupil and iris function
The pupil is a hole in the iris, which is a kind of anatomical continuation choroid.
Its function: regulation of light flux (provided by pupillary reflex).
Pupillary reflex is carried m.sphincter iridis, innervated by parasympathetic
division of the oculomotor nerve and narrowing the pupil, and m.dilatator iridis,
innervated by the sympathetic division of the superior cervical ganglion and
extending pupil. Adrenaline causes mydriasis, acetylcholine and eserine narrowing.
Expands the pupil during asphyxia, when dying body. Pupillary observed when
looking at a subject close the subject, under the effect of sympathomimetics.
Unequal pupil size is called anisocoria and may
observed for disorders (eg - a symptom of Horner).
Refractive errors
There are two main anomalies refraction in the eye - myopia and hyperopia.
Typically, they are not associated with failure of refractive media, and the anomaly
of the length of the eyeball.
Astigmatism: unequal refractive power of the cornea in different domains.
Corrected by cylindrical lenses.
Somatosensoric system
Pain (notsitseptivtive) sensory system is of particular importance for the survival of
the organism. Pain - an inevitable and constant companion of man, warning of the
dangers that protects the body. Pain is protective refleksornye reaction,
accompanied by autonomic changes: dilated pupils, vasoconstriction, increased
blood pressure, increased heart rate, muscle tension in the region.
A sudden, painful and persistent pain depresses the central nervous system, causing
disorder of homeostasis, leads to the development of a painful shock. Pain arising
under the action of any excessive stimuli. First to respond to stimulation of pain
receptors - free nerve endings located in superficial layers of the skin and inside
the body. With gain stimuli included other types of receptors (tactile, thermal),
conveying a powerful stream of pain impulses to the thalamus (subcortical level),
and then to the cortex. Localization of pain sensitivity in the cerebral cortex not
exactly clear. Stimulation of the cortex does not cause pain, so it is believed that
the center of pain sensitivity is the thalamus.
In the area of injury or tissue inflammation pain ensured the formation of
biologically active substances in the nerve endings of any type (histamine,
bradykinin, prostaglandins, Hageman factor). With increasing numbers of
receptors is able to perceive pain. Thanks to the "transformation" of the various
receptors in pain, the skin has a tremendous pain vigilance.
The first neuron pain sensory system lies in the spinal ganglia, the second in the
spinal cord, the third in the thalamus. In carrying pain signals involved rapidly
conducting myelinated fibers of group A at a rate of 8-30
-2
m / sec. Tactile signals are conducted with much greater speed than the pain. When
you hit the edge of the palm of your hand edge of the table appears first tactile
sensation, and then feeling the pain of primary brainstem, and then a growing sense
of long-latency pain. The main path of pain sensitivity - side spinnotalamichesky
lemniskovy way (via the medial lemniscus) and the lateral tract of the Morin (spinneck).
The temperature sensing system is of great importance for normal mechanisms of
thermoregulation. Receptors systems occur in the skin, cornea, mucous membranes
and internal organs. Thermoreceptors 2 types:
- Heat (Ruffini corpuscles)
- Cold (bulb Krause).
Free nerve endings that perceive pain, and perceived warmth. Neutral site of the
temperature scale ranges from 29 to 32 ° C, when a person does not feel any
warmth or cold.
Cold thermoreceptors transmit impulses to the rapidly conducting myelinated
fibers of group A heat receptors carry information on the slowly conducting
myelinated fibers of group C. The first neurons of the temperature sensor system
lies in the spinal ganglia, the second in the posterior horn of the spinal cord, the
third in the thalamus. The path of temperature sensitivity - the side of spinal
thalamic. With the simultaneous excitation of heat and cold receptors in humans
subjectively a feeling of "heat". An increase in body temperature (fever) there is a
feeling "chill". Feeling the cold more intensely than the heat, but more briefly,
since Krause bulbs lie more superficially in the skin.
Tactile sensory system provides the perception of touch, pressure, vibration.
Receptors system lie in the skin evenly. Their greatest number is on the lips,
fingertips and the tip of your tongue, in the skin of the breast nipples and genitals.
Free nerve endings, Entangling hair follicle respond to the lightest touch when you
reject the hair of 50. Merkel disks are located in the skin of the fingers. In the skin,
devoid of hair, Meissner corpuscles are located. More deeply into the skin cells lie
Pachchini, reacting to pressure and vibration. Method of two-point test identified
areas of the skin with the highest density of receptors. The smallest distance
between the legs of a compass Weber 1,1 mm determined at the tongue tip, 2,2 mm
- at your fingertips, 6,8 mm - at the tip of the nose, 8.9 mm - in the middle of the
palm, 67 mm - an average of the back.
The first neuron tactile sensory system lies in the spinal ganglia, the second - in the
posterior horn of the spinal cord, the third - in the thalamus, the fourth - in the
postcentral gyrus of the cerebral cortex. The main way of tactile sensitivity - front
spinetalamich.
Propreotseptivnaya sensing system provides a musculo-articular sense through
which is controlled by body position in space and relative position of its parts.
Proprioceptors are located in muscles, tendons and ligament-articular apparatus.
Proprioceptors (motor, sensory mechanoreceptors) are divided into 3 main types:
1 - Golgi bodies (twist around tendon fibers of muscle or svobodnolezhaschie)
2 - Pacinian corpuscles (lie in the fascia, tendons and joint capsule)
3 - neuromuscular and neuro-tendinous spindles (they have an elongated shape and
lie deep in the muscles). These receptors are composed of the capsule and passing
inside the intrafusal fibers (the remaining muscle fibers - extrafusal).
Receptors are the first and second types are excited muscle contraction and spindle
- with relaxation. Pulse stream of feedback received from all types of
proprioceptors, informs the central nervous system at any state of the muscles at
all, even the slightest changes in muscle tone.
Proprioceptive impulses sensitivity are the first neurons in the spinal ganglia, the
second neuron in the posterior horn is the spinal cord (nucleus Clarke), the third in the thalamus, the fourth - in the precentral gyrus of the cerebral cortex. Ways of
proprioceptive sensitivity - bundles Gaulle and Burdach, front and rear
spinomozzhechkovye way.
Visceral sensory system Vistseroretseptors (receptors of the internal organs) as
compared with exteroceptor has greater specificity with respect to the stimulus.
Among them are distinguished: chemoreceptors, osmoreceptors, barroretseptory
and pain receptors.
Shifts in the state of the internal organs associated with changes in the chemistry.
Osmotic and mechanical pressure, temperature, cause a change in the signals
received by the CNS. In response to this changing nervous and humoral control of
the organs.
Feature of the visceral sensory system is that it signals, as a rule. Not perceived by
man.
Pain, somatic and visceral sensory systems are closely linked viscerosensory
bonds. External skin receptors thus become intermediaries between the external
world and internal environment. Each organ has its representation in certain areas
of the skin. Such areas are called zones reflected pain, anyway - the projection
zones Zakharyin - Ged and the skin is a mirror of internal environment.
The olfactory sensory system
The olfactory sensory system is one of the leading systems involved in the
regulation of animal motivational behavior (defensive, food, sex). On the degree of
development of this system living organisms are divided into:
1 - makrosmatikov (highly developed sense of smell)
2 - mikrosmatikov (poorly developed sense of smell)
3 - anosmatikov (sense of smell is absent)
Man belongs to the group mikrosmatikov, but the sense of smell for it is one of the
most important functions. By mikrosmatikam are all primates and rodents, whereas
most mammals - makrosmatiki and Dolphins - anosmatiki.
In the evolution of olfactory organ, which was formed near the rictus, moved into
the nasal cavity, separating from the mouth .. For this reason, the mechanisms of
olfactory sensations similar to those of taste sensations. Olfactory epithelium is
laid on the fourth week of embryonic development in the olfactory pits mouth of
the bay of the embryo. When forming the nasal olfactory primordium shifts in its
cavity. Axons of olfactory receptor cells to sprout olfactory bulbs, which in its
development make a counter-movement as outgrowths of the olfactory cortex.
Olfactory organ (organum olfactum) - peripheral olfactory apparatus of the
analyzer, which lies in the upper nasal cavity. Part of the nasal mucosa, covering
the superior nasal concha and the upper section of the nasal septum, called the
olfactory region of nasal mucosa. This area is an area of 1 - 3 cm2 different
yellow-brown color due to the content of Bowman's olfactory glands that produce
mucus. Olfactory epithelium is called here is the olfactory receptor apparatus of the
analyzer. As part of the epithelium are three types of cells:
1 - olfactory (receptor)
2 - supporting,
3 - basal (regenerative).
Olfactory cells of which more than 10 million - bipolar. Their peripheral processes
are Expansion - bubble, armed with cilia. Olfactory mace (clava olfactoria)
otherwise - the olfactory vesicle van der Strihta. Central processes form the
olfactory nerves that penetrate in the number of 15-20 in the cranial cavity through
the perforated plate of the ethmoid bone to the olfactory bulb. Receptor cells are
highly sensitive, they perceive odorants (eg mercaptan) in ppm mg/m3. In this
tolko24 molecules of odorant in the air, reach the receptors.
Excitation of receptors occurs only in inspiration, while expiration is missing. Sami
receptors quickly adapt to the different smells. Smells are blocked by special
proteins - enzymes. Adaptation to one odor does not reduce the sensitivity to the
odorant of another species, because different odorous substances act on different
receptors.
Olfactory cells are chemoreceptors. There are several theories of smell, none of
which does not fully explain the mechanism of olfactory reception.
According to the theory of J. and R. Eymura Monkriffa (stereochemical theory),
the smell of a substance is determined by the size and shape of odorous molecules,
which configuration is suitable for the membrane receptor site "as the key to the
castle." The concept of receptor sites of various types, molecules interacting with
specific odorants suggests the presence of receptive sites of seven types (types of
odors: camphor, essence, floral, musky, spicy, mint, putrid). Receptive areas close
contact with odorant molecules, thus changing the charge site in the cell membrane
and there is potential. By Eymuru whole bunch of smells created by the
combination of these seven components. In April 1991, employees of Institute.
Howard Hughes (Columbia University), Richard Axel and Linda Buck discovered
that the structure of the receptor sites of the membrane of olfactory cells
genetically programmed, and these specific sites has more than 10 thousand
species. Thus, a person capable of perceiving more than 10 thousand smells
(1991).
By Zvaardemakeru there are 9 classes, which are divided into subclasses:
1 - Class efrirnyh odors (acetone, chloroform)
2 - class of aromatic odor (camphor, spicy, anise, lemon, almond)
3 - class of floral scents (vanilla)
4 - class musky odor
5 - Class garlic odor (hydrogen sulfide)
6 - class of burnt (balsam), smells (benzene, phenol),
7 - Class caprylic odor
8 - Class repulsive odors (quinine, pyridine),
9 - Class nauseating odor (indole, skatole).
According to the theory of Wright (vibration theory), the smell of a substance
depends on a certain frequency, inherent in the molecules of different substances.
Perhaps these variations are perceived not only by direct contact, but also
remotely.
There are probably receptive sites on the membrane receptor provides a spatial
coding of olfactory information with simultaneous frequency coding odor
intensity.
Impulses from receptors in the olfactory bulb receives (Blink node), which has a
seven-layer structure (similar to the cortical centers):
1 - layer of nerve fibers
2 - layer of the olfactory glomeruli,
3 - retiform outer layer
4 - layer of mitral cell bodies,
5 - retiform inner layer
6 - granular layer,
7 - epithelial layer (ependimny).
In the center of the olfactory bulb contains a channel whose walls are lined with
ependimotsitami. Large switching cells (mitral) combine their axons in the
olfactory tract bundles, which goes from the bulb to the olfactory structures of the
brain. Some of the cells of other layers are inhibitory interneurons (eg, granular
cells).
Olfactory tract, together with the onion are underdeveloped counterparts olfactory
gyrus, which is available in animals - makrosmatikov. Olfactory tract olfactory
forms a triangle, where the fibers are divided into separate beams. Part of the fibers
is to hook the hippocampus, another part goes through the anterior commissure to
the opposite side, a third group of fibers is transparent to the septum, the fourth
group - to the anterior perforated substance. At the hook end of the hippocampal
cortex is olfactory analyzer, which is connected to the thalamus, hypothalamic
nuclei, with the structures of the limbic system.
A person versed in the smells slightly, but the mouthfeel he developed very
strongly.
Gustatory sensory system
Taste sensations are related and are based on olfactory chemoreception. Organ of
taste (organum gustum) - peripheral gustatory apparatus of the analyzer before it
taste receptor cells, which are focused on taste buds in the tongue as the taste of
onions. Bulbs, there are about 2000.
As part of the bulb, there are 3 kinds of cells:
1 - taste (receptor)
2 - supporting,
3 - basal (regenerative).
Taste cells are armed with microvilli, in contact with whom flavorings provide the
appearance of the cells capacity. Receptors provide the perception of the four taste
qualities (salty, sweet, sour, bitter). Different combinations of the four taste
sensations can be guided in a wide range of tastes food. The set of taste sensations
caused by stimulation of not only taste but also tactile, thermal, olfactory receptors.
Receptive fields of perception of salty, sweet, sour and bitter are of different size
and location on the surface of the tongue.
To taste sensation occurs adaptation, the duration of which is proportional to the
concentration of the current solution. Adapting to the salty and sweet there faster
than a bitter and sour.
Impulses from the receptors on fibers tympani of the facial (VI) and
glossopharyngeal (IX) nerves come first in a single nucleus, which lies in the
caudal medulla. Axons of cells that transmit impulses to the nucleus of the
thalamus to the ventral zadnemedialnomu nucleus from which the information
arrives on the axons of cells in the cortex region of the seahorse and a hook where
the cortical end of the taste analyzer (for Bechterev).
In a normal sense of taste obtained by the interaction of gustatory and olfactory
analyzers.
Anosmia - loss of smell,
ageusia - loss of taste,
anorexia - loss of appetite,
bulimia - excessive appetite.
After 80 years, most people lose the sense of smell (United press nternatonal,
27.12.1984 city).
Illustrative material: L-OM1-14
REFERENCES:
Main:
1. Human Physiology, VM Pokrovsky., GF Korotko, M., 2004.
2. Guide to practical exercises on normal physiology. KV Sudakov, AV Kotov, M.,
2002.
3. Guidance on general and clinical physiology. V. Filimonov, MIA, 2002, 957 p.
4. Normal physiology, ed. KV Sudakov, M., 2000.
5. Aghajanian, NA, Tel LZ, Tsirkin VI, Chesnakova SA Physiology
rights. St. Petersburg, Sotis, 2000, 528 pp.
More:
8. "Fundamentals of human physiology," 1 and Volume 2, BI Tkachenko, St.
Petersburg, 1994.
9. 2. Iseman, RI, AD Gerasev, MV Iashvili. Physiology of excitable tissues.
Novosibirsk, Vol. NGPU, 1999., 125.
10. Alexandrov YI and other basics of Psychophysiology. Moscow, Infra-M,
1998., 431s.
11. Anatomy, physiology and hygiene in tables and diagrams. Manual. 1991.
12. Atlas of the normal physiology of AV Korobkov, SA Chesnokov, Moscow,
High School, 1987.
13. Handbook of physiological and laboratory parameters of healthy humans. AA
Utepbergenov, 1995.
14. Human Physiology. Ed. M. Pokrovsky, GF Korotko, in two volumes, Moscow,
2001, 368 pp.
Test questions (feedback):
1. Write down the formula for calculating visual acuity
2. What are the three main groups of vestibular disorders
3. How can I check the simulation of deafness
4. Carrying out the experiment with in a consistent manner
5. Demonstration of visual illusions
Medical University of Astana
Department of Physiology
Lecture № 15
Lecture theme: conditioned reflex activity of the organism and its
neurophysiological mechanisms.
Purpose: To provide knowledge of congenital and acquired forms of behavior,
learn to distinguish the unconditioned reflexes from the conventional, to formulate
the concept of the mechanism of closure of temporary connections, to impart skills
in conducting experiments to develop a conditioned reflex.
Plan of the lecture: Introduction. The concept of higher and lower activity.
Higher nervous activity-conditioned reflex activity of the leading departments of
the brain (in humans and animals, the cerebral hemispheres and the forebrain),
providing adequate and most perfect relationship of the whole organism to the
outside world, ie behavior.
Lower neural activity-the activity of the lower parts of the brain and spinal cord,
the heads of the main relations and integration of body parts to each other.
Congenital forms of behavior.
Animal behavior primarily directed at an individual and specific self-preservation.
In the process of phylogenesis formed a number of inborn reflexes, each of which
performs its specific functions and is involved in maintaining the normal
functioning of the body. The entire gene pool of innate reactions of an individual
represents a kind of "species (genetic) memory, contributing to themselves, their
progeny, populations and species. Fund inborn reflexes of each animal species
formed evolution in a way that would essentially an animal, was born and did not
have prior experience, was inherent in the primary repertoire of adaptive
behavioral responses. (Example: Worker stereotype. Fledgling provide. Hatching
from its egg, is accompanied. A sharp increase in the level of wakefulness and
increased muscle tone). But innate reflex can occur until the higher centers are not
yet ripe, but "disappears" as soon as senior centers will have the braking action.
(Example: newborn. Reenok). This is because it otnogeneticheskoe nervous system
development occurs in the caudal direction from the rear lower part of the brain,
where the centers of simple congenital reflexes, to the front, rostral, the higher
divisions. Since the appearance of an organism to light, he has all the integrated
system shall enter into a continuous interaction with the environment. Product of
this interaction is the behavior. In the process of individual development,
organisms learn what behavioral responses yield the best results, and in accordance
with that change their behavior. Holistic behavior includes two types of adaptive
reactions, genotypic caused genetic program, and phenotypic, due to the interaction
between genotype and environmental conditions, or individually purchased, based
on learning.
Unconditioned reflexes and their classification.
BR, which culminates in the formation of postnatal development, are genetically
predetermined and rigidly fitted to some relevant to this form environmental
conditions. Under the influence of early individual experience inborn reflexes
undergo significant changes. Attempts to describe and classify. BR has been done
a lot, and thus used different criteria: the nature of the cause of their stimuli, their
biological role, in the order they appear in this particular behavioral act. Yu.
Konkorsky br divided according to their bio. role in the preservative-reflexes,
providing regulation of the internal environment of the body (food, breathing, etc.);
reflexes preservation and procreation (sexual and caring for offspring), and the
protective reflex responses associated with the elimination of harmful agents
caught on the surface or inside the body (chesateln. reflex act of sneezing, etc.), the
reflexes of active Battlecr. or neutralized. noxious stimuli, objects (offensive or
aggressive reflexes), the reaction of passive-defensive behavior. A special group
marked orienting reflex to novelty, response to stimulus and target
orientirovochono-exploratory behavior. IP Pavlov divided unconditioned reflexes
into 3 groups: simple, complex and sophisticated br.
Among the toughest br he highlighted the following:
1) individual-food, active-and passive-defensive, aggressive, freedom reflex,
Research, reflex games;
2) species and sex and parent.
From an evolutionary point of view, every creature has a definite spatio-temporal
location in the geosphere, biosphere and sociosphere, but for a man and Noosphere
(intellektualn. developing world), although filogenetich. background of the last are
found only in higher animals. According to PV Simon, mastering each sphere
medium correspond to three different classes of reflections:
1. Vital br provide individual and species conservation body (food, defensive,
tentative).
Criteria:
1. dissatisfaction with the relevant requirements leads to physical destruction of
individuals,
2. br implementation does not require the participation of other individuals of the
same species.
2. Role (zoosotsialnye) br can be implemented only with the participation of other
individuals of its kind (sexual, caring for offspring, territorial behavior).
3. BR self oriented to the development of new space-time environments, pointing
to the future. (Issledov. behavior, freedom, game.) Feature of this group yavl. their
autonomy, it is not derivable from the other body's needs and is not reducible to
other motivations.
Instincts-complex unconditioned reflexes, which have continued the character of
the reactions when the end is a reflection serves as a signal to the beginning of the
next. Instincts are dependent on hormonal and metabolic factors. Characterized by
many features of the dominant.
The role of biological motivation for the life of the organism
Biological motivation - emotive biological needs that require satisfaction and
launching the implementation of a functional system to meet the need. Motivation
are divided into biological and social (human). Biological motivation, in turn, are
food (hunger with the appropriate emotional dissatisfaction), sex, defense and
others. Implementing them is carried out using the appropriate unconditional and
conditional reflexes.
Conditioned reflexes, their shapes, classification.
SD shapes. Under certain conditions individual. organism's life and disappear in
the absence of compliance. conditions, differing thus from congenital forms of
adaptation. All conv. p. divided into classical and instrumental, or ur types 1 and 2.
Fundamentals. sign of a conditioned reflex yavl. that the stimulus in the formation
of a temporary connection (learning) instead of properties. his unconditional
reaction begins to cause another, his uncharacteristic. Classification of conditioned
reflexes (often denoted by the name of ur br, based on which they worked):
On afferent link of the reflex arc, in particular on the basis of receptorexteroceptive release in accordance with the modality of the conditioned stimulus
produce visual, auditory, olfactory, gustatory, tactile, and temperature. They can be
developed for the type of objects, relations between them, the different smells, etc.
Ekterotseptiv. reflexes play a role in the relationship of the body with a circle.
environment, so they look. quickly. Interoceptive conditioned reflexes-image.
slower exteroceptive. Interoreceptors all types perform two functions: they
constitute the afferent link of specific autonomic reflexes games. important role in
maintaining homeostasis in the body, sending the info. status ext. bodies, they
affect the state of CISR Okaz. abstentions. at GNI. Sometimes singled out as a
separate group of proprioceptive ur.
On the efferent link of the reflex arc, in particular the effector that is manifested.
reflexes distinguish two groups: autonomic and motor, tool. To vegetative. include
salivary conv. reflex, as well as a number of motor-autonomic reflexes and
circulatory, respiratory, nutritional, pupillary, heart and t.d.V depending on the
nature of the effector apparatus of autonomic reflexes otlichchayutsya significantly
from each other as from the rate of conditional bond and on other features. Tools
For. probation. reflexes can be formed on the base course of reflex motor
responses. Instrumental conditioned reflex is not playing the unconditional
response, and in the implementation of such actions that would achieve or avoid
subsequent unconditioned reinforcement.
Forms of conditioned reflexes may be due to the nature and composition of the
conditioned stimulus, the type of reinforcement, as well as temporal relations
between associated stimuli. Conditioned reflexes in terms of temporal relations
between associated stimuli are divided into two groups: cash, in the case of
coincidence in time of the conditioned signal and reinforcement and the trace when
the reinforcement is presented only after the conditioned stimulus. Cash reflections
on the value of the interval between the insertion of associated stimuli are divided
into several species coincide (at least 1-3.) Of delayed (until 30) and delayed (rms
probation. Stimulus lasts 1-3 minutes). Trace ur form when reinforcement should
be after the end of a conditional stimulus. Conditioned reflexes to time, a special
kind of sea level. They are formed by regular repetition of the unconditioned
stimulus. (Naprim. feeding the animal every 30 min.) Depending on the structure
of the conditional signal ur divided into simple and complex. In other words
conditioned signals can be single or complex stimuli. Comprehensively. stimuli
may be simultaneous and sequential.
Regulation of conditioned reflexes:
- Conditioned stimulus must precede backed by the Be
zuslovnomu stimulus.
- The minimum time from the conditioned stimulus to the unconditioned is not
must exceed a certain value (for the defensive, for example - 0,1 seconds). This
time should not be too large.
- The cerebral cortex must be in an active state.
- Signal strength of the stimulus should be smaller than the unconditioned
reinforcement
Signals of a conditioned reflex can be any Exter vistseroi proprioceptive
stimulation.
Conditioned reflexes can be classified:
- The receptor field: Exter, viscero-, proprioceptive.
- By effector link: somatic and autonomic
- The biological value of food, defense, etc.
- The ratio of the time signal and reinforcement: coincident
delay and trace.
- According to the complexity: the first, second, etc. order.
Possible trace conditioned reflexes - not to the stimulus, and the
stop acting stimulus, whereas the stimulus itself may not induce a conditioned
reflex (especially if it does not apply in advance, and later the unconditioned
reinforcement).
Possible conditioned reflexes to time: when a certain time there is a conditioned
reflex, when it was at this time should have an unconditional reinforcement.
The more strongly unconditioned reinforcement in the process of
conditioned reflex, the more pronounced will be the conditioned reflex.
Conditioned reflexes may be of higher orders: the second when the conditioned reflex to a specific stimulus is preceded by a conditioned
stimulus, the third - when preceded by three conditioned stimuli, and so on until
the sixth order reflections, which can develop only in children.
According to Pavlov, the formation of a conditioned reflex is based on establishing
a temporary connection between the groups of cortical cells, which perceive the
conditioned and unconditioned stimuli. Have value as a horizontal associative way,
and the way "bark-subcortex-cortex." Interaction between cortical areas is carried
out according to specific (thalamus) and nonspecific (reticular formation) paths
through the sensory area of the cortex, where the primary information is processed,
and then descends again into the subcortical centers, from which is sent to the area
of cortical representation of unconditioned reflex - reinforcements. Has the value
of the dominant phenomenon: with unconditional stimulation excitability of
cortical centers increases and the center begins to react to the excitation coming
from other regions of the cortex, causing summation effect. In the formation of
conditioned reflexes first
include mechanisms for short-term and then long-term memory, as evidenced by
persistence of a conditioned reflex after deep anesthesia or cooling of the brain.
Conditioned reflex switching lies in the fact that one and
the same stimulus in different conditions can cause a variety of reflexes: for
example stimulus is reinforced in the morning feeding, and at noon - electric
shock, then the stimulus in the morning will cause the food conditioned reflex, and
at noon - the defensive.
The biological significance of conditioned reflexes, especially in their
participation in the process of learning, orientation to surroundings, acquisition
skills, providing the advantage of individuals.
Inhibition of conditioned reflexes
Externally, the unconditioned inhibition. Under the action of extraneous stimulus
(external) during the conditioned reflex, the conditioned reflex is inhibited. It is
relatively weak and short hampered indicative refreksom (fading brakes on
Pavlov), and much more inhibited conditioned signal of another of the conditioned
reflex. There is evidence for the fact that there is a great role played by the reticular
formation, which may inhibit not only effector departments, but also the sensory
elements of the reflex arc.
Protective inhibition (according to Pavlov) occurs when excessive
strong conditional signal. It has a protective value and prevent the debilitating
effects on the central nervous system of strong and prolonged stimulation. In
functionally weak organisms protective inhibition develops much faster than
active.
INSIDE, conditioned inhibition. In contrast to the unconditioned inhibition, which
arises at the first presentation of the stimulus, conditioned inhibition to develop.
Feature of internal inhibition in its fragility. Various functional overstrain or
violations primarily affect the internal inhibition.
- Fading: If the conditioned stimulus is no longer supported
unconditional, the conditioned reflex gradually diminishes and disappears.
Extinguished conditioned reflex can be for some time to recover, if during the
conditioned stimulus, a slow tentative stimulus: inhibition of the conditioned reflex
occurs (this happens due to increased cortical excitability during the orienting
reflex).
- Differentiation: the conditioned stimulus typically produces
generalized (eg sound enough any
sound, so there was a conditioned reflex). If in the process of
conditioned reflex certainly reinforce only the sound of a certain
tone, as a consequence of differentiation of conditioned reflexes to sound a tone
falters.
- Conditional brake: if the elaborated conditioned reflexes begin
accompany the prearranged signal to any other signal, and it did not accompany
this double conditioned stimulus, unconditioned, then this extension will be a
prearranged signal conditioned inhibition that can inhibit not only the reflex, in
which conditioned inhibition produced, but every other conditioned reflex
(conditioned inhibition becomes universal nature of the signal cancellation for any
of the conditioned reflex).
- Delay: If, after making an unconditional reinforcement
conditioned reflex to begin to push for a certain time from the conditioned signal,
and conditioned response will move away in time from the conditioned signal. This
delay also is based on the mechanism of conditioned inhibition: in the first
moments of the conditional signal acquires inhibitory value, and only after some
time becomes positive (disinhibition - a weak tentative stimulus - eliminates the
lag than prove the conditional nature of the braking delay).
The value of conditioned inhibition in the elimination of inappropriate reactions
have become superfluous. Inhibition of reflex activity is no less important than,
and elaboration of conditioned reflexes. In carrying out inhibition probably
involved the reticular formation of inhibitory cells in the brain.
Illustrative material: L-OM1-15
REFERENCES:
Main:
1. Human Physiology, VM Pokrovsky., GF Korotko, M., 2004.
2. Guide to practical exercises on normal physiology. KV Sudakov, AV Kotov, M.,
2002.
3. Guidance on general and clinical physiology. V. Filimonov, MIA, 2002, 957 p.
4. Normal physiology, ed. KV Sudakov, M., 2000.
5. Aghajanian, NA, Tel LZ, Tsirkin VI, Chesnakova SA Physiology
rights. St. Petersburg, Sotis, 2000, 528 pp.
More:
1. Physiology of higher nervous activity with the basics of neuroscience.
Author: Shul'govskil VV, 2003, 464 pp.
2. Physiology of Higher Nervous Activity and sensory systems. Batuev IK, St.
Petersburg, 2004, 356.
3. Iseman, RI, AD Gerasev, MV Iashvili. Physiology of excitable tissues.
Novosibirsk, Vol. NGPU, 1999., 125.
4. Alexandrov YI and other basics of Psychophysiology. Moscow, Infra-M, 1998.,
431s.
5. Anatomy, physiology and hygiene in tables and diagrams. Manual. 1991.
6. "Fundamentals of human physiology," 1 and Volume 2, BI Tkachenko, St.
Petersburg, 1994.
7. Atlas of the normal physiology of AV Korobkov, SA Chesnokov, Moscow,
High School, 1987.
8. Handbook of physiological and laboratory parameters of healthy humans. AA
Utepbergenov, 1995.
9. Human Physiology. Ed. M. Pokrovsky, GF Korotko, in two volumes, Moscow,
2001, 368 pp.
10. Physiology of higher nervous activity. Voronin, LM: [Textbook. Manual for
Biology. specials. University comrade-M. Vyssh. School, 1979
11. Delgado, H. Brain and consciousness. Moscow, Mir, 1971., 264s.
12. Alexandrov YI and other basics of Psychophysiology. Moscow, Infra-M,
1998., 431s.
Test questions (feedback):
1. Differences conditioned on unconditioned reflexes.
2. Classification of conditioned reflexes.
3. Physiological mechanisms of conditioned reflexes.
4. Dynamic stereotype, its physiological nature, the importance for learning and
work skills.
5. Conditions of formation and a technique of conditioned reflexes (Pavlov).
6. What is the essence of differential inhibition
7. What is the orienting reflex?
Medical University of Astana
Department of Physiology
LECTURE № 16.
Lecture theme: Teaching IP Pavlov on the first and second signal systems. Types
of GNI. Physiology of sleep.
Purpose: To provide knowledge about the types of GNI, to learn to differentiate
types of GNI, extra-and intravertirovannyh individuals to formulate a notion of
higher mental functions, to impart skills to conduct psychological testing to
identify types of GNI and mental functions.
Abstracts of lectures:
Introduction. The general concept of temperament
When people talk about temperament, then we have in mind many of the mental
differences between people - differences in the depth, intensity, emotional stability,
emotional sensibility, tempo, energetic action and other dynamic, individualresistant features of mental life, behavior and activities. However, temperament,
and today remains largely controversial and unresolved issue. However, despite the
variety of approaches to the problem, scholars and practitioners recognize that
temperament - the biological foundation upon which personality is formed as a
social being.
Temperament has a strong influence on a person's character, his behavior, as well
as overall health. Features of temperament and affect in educational classes and
employment. That is why the study of temperament types and their influence on
activity is not only useful but also necessary, especially for workers and
management areas,
Temperament (Latin Temperamentum - a proper balance of features tempero - mix
in good condition) - characteristics of the individual from the dynamic features of
his mental activity, ie tempo, speed, rhythm, intensity, these activities constitute
the mental processes and states.
Temperament - the quality of personality that has been formed in the personal
experience of rights based on the genetic condition of its type of nervous system
and largely determines the style of his work. Temperament refers to biologically
driven substructures of personality.
There are four basic types of temperaments: sanguine, choleric, phlegmatic and
melancholic.
Temperament reflects the dynamic aspects of behavior, mostly innate, and
therefore the properties of temperament are the most stable and consistent
compared with other mental qualities of man. The most specific feature of
temperament is that various properties of the temperament of the person is not
randomly combined with each other, and naturally connected with each other,
forming a specific organization structure.
Thus, under the temperament to be understood individually distinctive properties
of the psyche, defining the dynamics of human mental activity, which is equally
manifested in a variety of activities, regardless of its content goals, motives, remain
constant in adulthood and in the relationship is characterized by the type of
temperament.
Doctrine Pavlov's temperament
In fact, long been known dependence of the flow of mental processes and behavior
of the nervous system, acting as a dominant and management role in the body.
Communication theory some general properties of nervous processes with the
types of temperament has been proposed IP Pavlov and was developed and
experimentally confirmed in the works of his followers.
Pavlov, studying the characteristics of conditioned reflexes in dogs, drew attention
to individual differences in behavior and in the course of conditioned reflex
activity. These differences manifested themselves primarily in such aspects of
behavior such as speed and accuracy of conditioned reflexes, as well as the
peculiarities of their decay. This fact has made it possible to Pavlov hypothesize
that they can not be explained only by a variety of experimental situations and that
they are based on some fundamental properties of neural processes - excitation and
inhibition. These properties include the strength of excitation and inhibition, their
balance and mobility.
Pavlov, distinguished by the imagination and the drag force, believing them to two
independent properties of the nervous system.
The strength reflects the efficiency of excitation of a nerve cell. It manifests itself
in functional endurance, ie, the ability to withstand long or short, but very excited,
not passing while in the opposite state of inhibition.
The braking force is understood as the functional capacity of the nervous system in
the implementation of inhibition manifests itself in the ability to form different
inhibitory conditioned responses, such as fading and differentiation.
Balance - a balance of excitation and inhibition. The force of the two processes
determines whether the individual is balanced or unbalanced, where the force of
one process greater than the force of another.
Mobility - the nerve processes - reflected in the rate of transition from one nerve
process to another. Mobility of nervous processes is manifested in the ability to
change their behavior in response to changing conditions of life. Measure this
property of the nervous system is the speed of transition from one activity to
another, from a passive to an active state, and vice versa.
Inertia - the opposite of mobility. The nervous system is even more inert, more
time or effort required to move from one process to another.
Dedicated Pavlov properties of nervous processes in which certain systems, a
combination that in his opinion, form the so-called type of the nervous system, or
the type of higher nervous activity. It consists of typical individuals set the basic
properties of the nervous system - the power, balance and mobility processes,
distinguishing between strong and weak types. A further reason is the division of
steadiness of nerve processes, but only for strong types, which are divided into
balanced and unbalanced, and the unbalanced type is characterized by a
predominance of excitation over inhibition. Strong balanced types are divided into
mobile and inert when base division is the mobility of nervous processes.
Dedicated Pavlov types of nervous system, not only in quantity, but also on the
main characteristics correspond to the 4 classical types of temperament:
1. strong, well-balanced, agile - sanguine;
2. strong, well-balanced, inert - phlegmatic;
3. strong, unbalanced type with a predominance of excitation - choleric;
4. weak type - melancholic.
Pavlov knew the type of nervous system as innate, relatively little affected by
changes under the influence of environment and upbringing. According to Pavlov,
the properties of the nervous system form the physiological basis of temperament,
which is a mental manifestation of the type of nervous system. Types of nervous
system, established in animal studies, Pavlov suggested to distribute to people.
At present, science has accumulated a lot of facts about the properties of the
nervous system, and to the extent of their accumulation researchers give all equally
important types of the nervous system primarily emphasizes the importance of
individual studies the fundamental properties of the nervous system, while the
problem of separating the types recedes into the background . Because types are
formed from combinations of these properties, only a deeper knowledge of the past
can provide the understanding and implementation of typologies.
But certainly, that each person has a very specific type of nervous system
manifestation of which is characteristics of temperament, are the important side of
individual psychological differences.
Psychological characteristics of temperament types
Creator of the theory of temperament is the ancient Greek physician Hippocrates
(V in. BC). He argued that people differ by 4 main "juice" of life - blood, phlegm,
yellow bile and black bile - its member. On the basis of his teachings, the most
famous physician of antiquity after Hippocrates, Claudius Galen (II century. BC)
developed the first typology of temperament, which he described in a famous
treatise "De temperamentum". According to his teaching style temperament
depends on the dominance in the body of one of the juices. They were identified
temperaments, which nowadays widely known: sanguine (from Lat. Sanguis -
"blood"), phlegmatic (from the Greek. - Phlegma - "phlegm"), choleric (from the
Greek. Chole - "bile") and melancholic (from the Greek. melas chole - "black
bile"). This is a fantastic concept has a huge impact on the scientists for centuries.
Under the temperament to be understood individually distinctive properties of the
psyche, defining the dynamics of human mental activity, are equally manifest in a
variety of activities, regardless of its content, purposes, motives, remain constant in
adulthood and their mutual respect characterize the type of temperament. Concrete
manifestations of such diverse temperaments. They are not only noticeable in the
outer demeanor, but seemed to pervade all aspects of the psyche, essentially
manifested in the cognitive activity, the sphere of feelings, motives and actions of
man, as well as in the nature of mental work, peculiarities of speech, etc.
At the present time, science has enough facts to give a complete characterization of
all types of psychological temperament of a certain coherent program. However,
for the preparation of the psychological characteristics of the traditional 4 types of
commonly identify the following basic properties of temperament:
Sensory determined by what is the smallest power of external influences, necessary
for the emergence of a mental reaction of man, and what the rate of this reaction.
Reactivity is characterized by a degree of automatic responses to external or
internal influences of equal strength (criticism, hurtful words, a sharp tone - even
the sound).
Activity indicates how intensely (energetically) a person affected by the outside
world and overcome obstacles in achieving goals (persistence, focus, focus).
Value determines the reactivity and activity, from which a greater degree of envy
of human activity: from accidental external or internal circumstances, mood,
random events), or the objectives, intentions and beliefs.
Plasticity and rigidity show how easy and flexible to adapt man to external
influences (plasticity), or as inert and tap the behavior.
Extroversion, introversion determines from which mainly depend on the reaction
and human activity - from the outside impressions that arise at the moment
(extrovert) or from the images, ideas and thoughts related to past and future
(introvert).
Given all of these properties, we can provide the following psychological
characteristics of the major classical temperament types:
Sanguine. People with high reactivity, but the activity and reactivity in him
balanced. He quickly, excitedly responds to everything that attracts his attention,
has a lively facial expressions and expressive movements. By a slight laughing
about it, but insignificant fact may annoy him. His face is easy to guess his mood,
attitude to the subject or person. He has a high threshold, so he does not notice the
very faint sounds and visual stimuli. With its increased activity and being very
energetic and workable, it is actively taken up a new business and can operate for
long without tiring. Able to quickly focus, disciplined, if desired, can inhibit the
expression of their feelings and knee-jerk reaction. He has the fast motion,
flexibility of mind, quick wit, fast-paced speech, the rapid inclusion of new work.
High ductility is manifested in the variability of feelings, moods, interests and
aspirations. Sanguine friends easily with new people, get used to the new
requirements and circumstances. Without the efforts of not only switches from one
job to another, but to be retrained, mastering new skills. As a rule, it is more
responsive to external impressions than on subjective images and ideas about the
past and the future, an extrovert.
In sanguine feelings easily arise, easily replaced. The ease with which a sanguine
formed and remake new temporary connection, high mobility of the stereotype, is
also reflected in the mental mobility sanguine, reveal a certain tendency to
instability.
Choleric. How sanguine and have low sensitivity, high reactivity and activity.
But choleric reactivity clearly prevails over the activity, so it perish, unrestrained,
impatient. Quick-tempered. It is less flexible and more inert than sanguine. Hence the greater stability of the aspirations and interests, much persistence, may be
difficult to switch attention, but rather an extrovert. People of this temperament are
fast, extremely mobile, unbalanced, excitable, all mental processes occur in them
quickly, intensively. The predominance of excitation over inhibition, typical of this
type of nervous activity, evident in incontinence, impulsiveness, temper,
irritability, choleric. This and expressive facial expressions, hurried speech, jerky
gestures, unrestrained movement. Feelings of a man choleric temperament,
strengths, usually conspicuous, occur quickly, sometimes the mood changes
dramatically. Imbalance inherent in choleric, hot links and its activities: it increases
the passion and even takes this case, pointing at the same impetuosity and rapidity
of movement, work with enthusiasm, overcoming difficulties. But a person with a
choleric temperament supply of nervous energy can be quickly exhausted in the
process and then may come a sharp decline in activity: the rise and excitement
fade, the mood is sharply declining. In dealing with people choleric admits
sharpness, irritability, emotional outburst, which often does not give him an
opportunity to objectively assess the actions of people, and on this ground, it
creates situations of conflict in the team. Excessive straightforwardness, short
temper, harshness, impatience sometimes make hard and unpleasant stay in a group
of people.
Phlegmatic has high activity significantly above the prevailing low reactivity, low
sensitivity and emotionality. Its hard to laugh and grieve - when around loud laugh,
he can remain calm. With a lot of trouble remains calm. Usually he has a poor
body language, movement inexpressive and slowed down, as well as speech. He
nenahodchiv with difficulty tends to focus and adapt to new surroundings, slowly
rebuilding the skills and habits. However, he is energetic and hardworking. Differs
patience, fortitude and self-control. As a rule, it is difficult to converge with new
people, poorly responsive to external impressions, an introvert.
The disadvantage is phlegmatic its inertia, stiffness. Inertia also affects the rigidity
of its stereotypes, the difficulties of its restructuring. However, this quality, inertia,
and has a positive value, contributes to the permanence of thoroughness of the
individual.
Melancholic. A person with high sensitivity and low reactivity. Increased
sensitivity at high inertia leads to the fact that little excuse can make him tear it
unduly touchy, morbidly sensitive. Facial expressions and movements of his
inexpressive, his voice quiet and traffic are poor. He usually unsure of themselves,
shy, the slightest difficulty in forcing his resignation. Melancholic neenergichen,
nenastoychiv, easily tired and a little hardworking. He inherent easily distracted
and erratic attention, slowing of mental processes. Most melancholic - introverts.
Melancholic shy, indecisive, timid. However, in a quiet, familiar surroundings
melancholic can successfully cope with life's challenges.
Can be regarded as already firmly established that the type of temperament in
human innate, but on what exactly its inherent properties of the organization, it
depends, not yet fully elucidated.
The modern notion of character accentuation.
In contrast to the classical understanding of the types of higher nervous activity in
the clinic uses a more detailed classification of a person's character. Depending on
the severity of this can
be easily prevalence of certain traits, expressed accentuation
character and borderline pathological condition, passing in psychopathy.
Distinguish accentuation:
- Paranoia: A strong, categorical, obsessed with the very real idea to execution
which is methodically and purposefully.
Able to become a leader and manager, povseti behind. Capable
become a tyrant. Reasonable, nothing ventured nothing, unless it is
As for his goal. Can be oppressive and evil. In conversation reveals
own superiority, demanding to themselves and others. Educates children in a strict
and sober approach to life. Family Life
likened to industrial relations. Prudent, wise. It Athos
Caesar, Peter I, Napoleon, Bismarck, Churchill, Lenin. The best way to
influence on him - to convince themselves that the required work from him or
actions as well as possible consistent with their wishes and ideas.
- Epileptoid: Meticulous and precise, carefully calculated
action, is prone to organizational work, organize. Each
thing in place, each case is scheduled, every hour is painted. If
got down to business - will bring to the end, no matter what - it's important or not.
Do not be satisfied without first checking all he had done. Neat, tidy,
communication style always match their surroundings. This
workhorse: lucky not knowing fatigue. Invaluable as a model of reliability and
confidence. This Karenin, Bazarov, is a collective image
"Chief accountant" is Haydn, Darwin, Tolstoy.
- Isteroid: artsy, eccentric, causing the type and style of communication, needs
constant attention from others and will go to any act (heroic or villainous) in order
to attract the attention of others to his person (in the world, and death is red).
Consumer setting to life. Believes that everyone around him must
is only because he lives on in the world. Requires greater attention, without
offering anything in return. Type of artist, bohemian
personality. Great possibilities of reincarnation. If this type of accentuation is
combined with a talent in any field of art,
can become a creator, if not - is "unrecognized genius".
The whole meaning of life - to be seen, surprise, shock. Infantile,
labile, demonstrative. This is D'Artagnan, Rakhmetov, Wagner, Chaliapin
Muhammad Ali, Michael Jackson, Maradona, Madonna, Picasso. Method
influence on him - more him praise and admire them, but especially in the presence
of a large audience: then able to do everything
in order to re-earn the admiration of self.
- Schizoid: Not of this world. Minimum attention to others, as
indeed, on himself. May have a groomed appearance, moreover, does
this does not suffer. Does not choose expressions that do not hesitate in any
audience, however - not particularly in need of this audience. If
somewhat busy, devotes himself to just this business, which soon becomes a
professional. Generator of ideas. Original and extravagant way of thinking, may
find a completely unexpected solution to the problem
or issue. At the same time is not inclined to routine work, the practical
implementation of their findings. Most often, highly erudite, and circle
interests wide. At the same time - too late to start a family or does not create
in general, there is little practical in everyday terms, poorly versed in interpersonal
relationships, even close to it the circle of communication. Many
actions of countries, although strangely this does not notice. Inclined to
loneliness, to independent work, often obsessed with some idea
and is doing everything to resolve it. Life's troubles pass
him, he simply does not notice. This type of literary eccentric professor, is Edison,
Marx, Einstein. To the extreme stubborn and willful, can not be any impact.
Gipertimik: Always cheerful, zhineradosten, good-natured. Tend to find joy in all
everyday situations, food, drink, physiological functions. Easy to communicate,
makes any promises
then fails to comply with, swears by anything and forget about it through
half an hour. Quickly switch from one activity to another,
does not extend to the end of anything. Type of gossip and chatterbox: ready to
shoot the breeze
about anything and with anyone, and quickly jumps from topic to
theme, does not listen to the interlocutor. Communicate to him - not the exchange
of information and conversation for the sake of conversation. Incapable of
productive work, not to bring it to the end, however, sometimes is not taken for
him.
Empty and unrealistic fantasies without seeking to embody. Pleased with himself
themselves, the environment surrounding. Life is more plant - satisfaction of
physiological needs, which can furnish with taste.
Knowledge, and judgmental, thinking more specific. Soul to
plowing, hospitable gentleman, sybaritic. This Nozdryov, Manila, Porthos,
Oblomov. Historical comparisons do not - such a history does not remain.
Recognizes the force. Way to affect - to make.
Cycloids: Man mood, on which depends the efficiency and
and communication. Fluctuations affect, contradictory nature. Maybe
enthusiastic to the extreme and just as fast to cool down. Inclined to gentle
mental relations, amorous, and full of love, touchy, emotional.
Way to affect - to show friendship without flattery and toadying, sincere interest.
Psychasthenic: Type killjoy, always dissatisfied with others and themselves. Not
seeks to society, and if there is, it does not improve the general atmosphere, as,
indeed, their own mood. May
be giperestetom, which offends a little bit bad form
word or smell. To the extreme touchy, vindictive. Work selects
quiet and calm, does not break for big money, not zvataet stars
from heaven, and not like those who are trying to do: call upstarts.
Type of snail, curled in its shell, philistine, block off your little world to the home.
Does not take money, but never ask. For the family - a walking mountain. Constant
nagging and complaints. Not
God forbid an animal in the room. Labile. Drives the slightest trouble in
tears, lost in new surroundings, hardly makes acquaintance,
comes into contact. Ipohondrical: inclined to seek in their various diseases, it treats
them all the available methods. A constant object of concern to the local doctor,
and even for the entire clinic.
Constant in the habits and affections, painfully aware violation of the stereotype.
There are also some other types of accentuation.
I and II signaling systems.
I alarm system - analysis and synthesis of direct, specific signals of objects and
phenomena of the external world, the reality. It is common to human and animal
warning system.
II signaling system - associated with speech, verbal. Based
on the analysis and synthesis of verbal and abstract representations of objects and
phenomena where direct their sense is not required.
Characteristic only of humans. Is the foundation of social life, and simultaneously
develops only in a society.
Basic laws of excitation and inhibition are common to both
the first and the second signal system.
Conditioned signal may be a stimulus itself, as well as verbal designation of this
stimulus. During the elaboration of a conditioned reflex to the bell, not only is his
call, but the word "call". This phenomenon is called elective iraadiatsiey, namely,
to
that the excitation of the first signaling system are passed to the second and vice
versa. Conditioned reflex may occur, and the word-synonym
conditioned stimulus, but similar-sounding word quickly produced
differentiation. Conditioned reflex occurs as if the spoken word - the prearranged
signal to replace written by the same word.
It is possible to develop and autonomic reflexes to verbal stimuli.
Keep in mind that for the second signal system left hemisphere is more important.
Physiological mechanisms of sleep and wakefulness
The most significant symptoms of sleep:
- Lowering the activity of the CNS and the cessation of contact with others.
- A decrease in muscle tone.
- Reduction of all kinds of sensitivity.
- Dramatically weakened reflex function.
- Inhibited reflexes.
- The threshold for stimulation of reflexes increased, the latent time increased.
- Decreased metabolism.
- Reducing heart rate and respiratory rate.
- Reduced blood pressure.
- Decreased urine output.
- Lowering body temperature.
If you dream there are characteristic changes in the electroencephalogram:
- There are high-amplitude alpha waves
- Then theta waves and delta waves in the phase of slow wave sleep.
- In a period of REM (rapid) sleep appears low amplitude high frequency activity.
In a phase of slow sleep a person completely paralyzed and can not see dreams.
Periods of REM (rapid) sleep make up 20-25% of the total
duration of sleep during these periods indicated movement of the eyeballs,
reduction of facial muscles, a few pulse quickens, blood pressure rises. During
these periods man has dreams. Dreams occur periodically at intervals of 80-90
minutes.
Phases of sleep:
- Drowsiness, sleep
- Slow Dream
- REM sleep (REM).
- Wake.
Types of sleep:
- Periodic daily sleep (mono-, di-, and polyphasic).
- Periodic seasonal dream, suspended animation, hibernation.
- Narcotic sleep.
- Hypnotic sleep.
- Abnormal sleep.
In certain circumstances occur, "partial wakefulness state when there is a kind of hibernation, "a guard, point,
very sensitive to the strictly defined stimulus. For example,
Hypersensitivity to the ringing tone, the voice or the movement of a sleeping child
from the mother and the other belongs to the hypnotic sleep
precisely to such a variety of sleep.
Sleep disorders:
- Insomnia - the inability to fall asleep.
- Narcolepsy - constant drowsiness.
- Lethargy (refers to abnormal sleep).
- Symptom false spillage.
Theory of sleep:
1. Pavlov: the dream is the result of generalized deceleration
tion in the cerebral cortex, extending to the subcortical
centers. This is confirmed by the fact that the repeated application of
differentiation or conventional brakes often evoked in the dog drowsiness and
sleep.
2. In the occurrence of sleep recognizes the important role gipnogennymh
structures of the brain stem. These structures were discovered by Hess in certain
areas of non-specific thalamic nuclei. Irritation of these structures with the help of
microelectrodes is the animal sleep, no different from
normal saline. It was shown that these structures are in antagonism to the reticular
formation and inhibit its facilitating effect on the cortex and subcortex.
Entsefalograficheski stimulation of these
zones caused synchronization of cortical activity and sleep, whereas the reticular
formation - desynchronization and arousal.
3. Morutstsi opened another gipnogennuyu zone in the medulla oblongata and
in the lower pons and irritation which also causes the synchronization of brain
activity. These units belong to the reticular formation and its caudal portion, which
has an inhibiting
impact on both the spinal cord, and in the overlying units.
4. Mediator theory of sleep attaches great importance to the influence of
acetylcholine (the introduction of acetylcholine or cholinesterase inhibitors in
gipnogennye area induces sleep, and, atropine removes this effect), norepinephrine
(his introduction to the appropriate areas of the brain causes the awakening),
serotonin and dopamine, allocates a certain brain structures.
5. Humoral theory of sleep explains the dream the influence of certain substances
(gipnotoksinov or bromgormonov) accumulated in the body
waking state. In favor of this view is the fact
that the blood of the long-term sleeping dogs, being introduced just
slept evoked posleney sleep.
6. Anokhin combines the above theory: the dream starts with
eliminate the inhibitory influence of tired of the cortex to the center of Hess, who
is excited and hinders the reticular formation, which ceases
have facilitating effects on the cerebral cortex and begins its
spilled slowdown.
The value of sleep is currently under review not only as a process of recreation but
also as a condition for the unimpeded flow of
plastic processes in the CNS, when, in the absence of external stimuli
Recycling is the day gathered information transfer relevant information from shortterm memory into long-term (process
consolidation engrams)
Illustrative material: L-OM1-16
REFERENCES:
Main:
1. Human Physiology, VM Pokrovsky., GF Korotko, M., 2004.
2. Guide to practical exercises on normal physiology. KV Sudakov, AV Kotov, M.,
2002.
3. Guidance on general and clinical physiology. V. Filimonov, MIA, 2002, 957 p.
4. Normal physiology, ed. KV Sudakov, M., 2000.
5. Aghajanian, NA, Tel LZ, Tsirkin VI, Chesnakova SA Physiology
rights. St. Petersburg, Sotis, 2000, 528 pp.
More:
1. Physiology of higher nervous activity with the basics of neuroscience.
Author: Shul'govskil VV, 2003, 464 pp.
2. Physiology of Higher Nervous Activity and sensory systems. Batuev IK, St.
Petersburg, 2004, 356.
3. "Fundamentals of human physiology," 1 and Volume 2, BI Tkachenko, St.
Petersburg, 1994.
4. Alexandrov YI and other basics of Psychophysiology. Moscow, Infra-M, 1998.,
431s.
5. Anatomy, physiology and hygiene in tables and diagrams. Manual. 1991.
6. Atlas of the normal physiology of AV Korobkov, SA Chesnokov, Moscow,
High School, 1987.
7. Handbook of physiological and laboratory parameters of healthy humans. AA
Utepbergenov, 1995.
8. Human Physiology. Ed. M. Pokrovsky, GF Korotko, in two volumes, Moscow,
2001, 368 pp.
9. Physiology of higher nervous activity. Voronin, LM: [Textbook. Manual for
Biology. specials. University comrade-M. Vyssh. School, 1979
10. Delgado, H. Brain and consciousness. Moscow, Mir, 1971., 264s.
11. Alexandrov YI and other basics of Psychophysiology. Moscow, Infra-M,
1998., 431s.
Test questions (feedback):
1. List the types of GNI by Hippocrates
2. Name three properties of the CNS to determine the type of GNI
3. What type classification used in the practice of GNI
4. List the main stages of sleep
Medical University of Astana
Department of Physiology
Lecture № 17.
Lecture theme: human mental activity. Memory. Emotions. Motivation
Purpose: Knowledge of the physiological bases of the formation of higher mental
functions is essential for determining the shifts and choice of tactics appropriate
correction of the changes disciplines. Determining the level of short-and long-term
memory. The study of the physiological mechanisms of attention, perception,
thought, consciousness and other higher mental functions allows for accurate
analysis of the phenomena related to higher mental functions.
Abstracts of lectures:
Perception.
Perception - a reflection of objects and phenomena of objective reality, which
arises on the basis of the synthesis of sensations and perceptions
senses.
Renewal of the images created on the basis of previous perceptions, called the
representation. For the realization of the representation needed
long-term memory. Extremely accurate representation of the past
perception called eydetizmom is rare.
CHARACTERISTICS OF PERCEPTION.
Power of perception Quality of perception CHANGES AND BREACH OF PERCEPTION.
Violations of the perception may be based primarily on offense
sensations, which include: gipostezii, hyperesthesia, paresthesia.
Illusion - an erroneous perception of a real object. (Illusion
Aristotle's illusion of visual, auditory, etc.). For the occurrence of
illusions essentially a state of consciousness, emotional background (affective
illusion).
Hallucinations: false perceptions is not an existing facility. Symptom
mental disease or intoxication. Rarely can accompany
and somatic disorders. Divided into simple (and fotopsii
etc.) and complex. Complex are divided into psevdogallyutsinatsii ("show picture")
and true (delirium, the patient himself is involved in the hallucinatory events). By
type of analyzer hallucinations are visual, auditory, tactile, common sense, smell.
For violations of perception are the symptoms of derealization and
depersonalization.
Special disorder of perception - agnosia - neuznavanie well
familiar objects and phenomena. They occur mostly in the background of the
organic CNS lesions and may be visual, auditory, etc.
Attention.
Attention - mental focus on specific objects,
focus on them.
Initially, attention was referred to the adaptive reflexes
(Ribot), or sensory and motor settings (LS Vygotsky).
The value of the work of Pavlov and Ukhtomsk in the understanding of attention it
definition of this process in light of the teachings of the dominant, as
prevailing focus of excitation, attracting to itself all the irritation. Of great
importance here is the process of negative induction,
when excited center inhibits the surrounding area. Pavlov defined the process of
attention by the presence of cortical lesions "optimal excitability, changing the
location, size, but always surrounded by
periphery of a lower excitability or inhibition.
Properties of attention:
Orientation - selective nature of it.
Concentration, the intensity - the degree of deepening in this
activities.
Stability - the ability to maintain long-term directed concentrated
dotochennost.
Attention span - the number of objects covered by the attention
Niemi. Depending on the volume distinguish concentrated (in one
object) and distributed (many locations) account.
Attention is involuntary or passive (having a value innovation, state of the human
psyche) - which is based on the orienting reflex, and arbitrary or active (associated
with consciously set goal) - based on the decision taken at
participation of volitional processes.
Attention may be their outward - to the objects of the external world and inner
direction - on their own experiences, thoughts, mental
activities.
Violation of attention.
Distraction of attention - easy involuntary switchable
very low-intensity focus (children astenizirovannye patients
umomlennost).
Rigidity of attention - a small switchable stability of attention,
as a result of all that is not directed attention to fall out of the field
view.
Starikovsk’s distraction - a weak intensity at low switchable attention.
Memory.
Memory - it traces the processes that remain in the system after
of stimuli. Reflection of past experience, which consists in
memorization, conservation, and subsequent reproduction and recognition
what was previously perceived, experienced or done.
The study of memory dates back to Aristotle, then the memory has been studied
Descartes, Locke, Hume, Spencer, Millholm. It was mostly mechanical view to a
greater or lesser extent explained by individual memory. Ribot divided the memory
for static and dynamic. R. Semon suggested that the term "engram", but he
understood them literally, as the imprint of images directly in the cells of the cortex
with a special kind of vibration. In recent decades, there was a certain theory of
memory, what is the merit Hidena, Dingmena, Rose,
Kreps, Palladin, Banshchikova etc.
Types of memory and physiological mechanisms.
According to analyzers, accepted irritation:
- Visual,
- Auditory,
- Emotional,
- Locomotion.
Memory is divided into:
- Mechanical.
- Notional.
- Involuntary (important novelty and strength of the stimulus).
- Arbitrary (important attention and volitional activities).
Depending on the time characteristics and the physiological mechanism of the
modern view memory is divided:
- Instant (trace in the analyzer) - physiologically - trace processes in the receptor
cells - 1 sec.
- Short-term (the trace in the neurons centers) - physiological
mechanism is defined as reverb impulses in cyclic chains
neurons. - Minutes, hours.
- Long-term memory - the consolidation of the following information (engrams).
To move to the long-term memory are important: the significance of information,
frequent repetition of information, unconscious memorizing facts (subliminal). The
mechanism is based on a synthesis of
specific substances: proteins and nucleic acids. Starting the process
by activation of adenylyl cyclase mediated, formation
c-AMP, which activates protein kinase: synthesis takes place specific "protein
memory". In the process of consolidation are significant ACTH, vasopressin,
endorphins.
With the help of the right hemisphere is fixed in the main memory is shaped by the
left - verbal-logical.
In the mechanism of many is not known. Kept for life and
used: random, inadvertently and unintentionally-associative.
Memory impairment.
Gipomneziya: poor memorization. May be associated with more
useful, and the type of GNI, psychological characteristics of people, badly trained
memory.
Gipermneziya: high, sometimes phenomenal memory. Phenomenon
rare, are not studied.
Retrograde amnesia: a violation of mostly short-term memory, such as head injury
falling from the memory of all that immediately preceded the injury.
Simultaneously, long-term memory is unaffected.
Korsakoff syndrome: disturbance of memory, no memory
on current events, whereas the distant past remain. In the mechanism of syndrome
of the absence or drastic reduction of the transition of information from
short-term memory into long-term. Characteristic of chronic
alcohol intoxication and some other CNS lesions.
Paramnesia: Errors recall, transfer events in time.
Perseveration: intrusive recollections, unrelated to
environment and situation.
Reminiscences: memories retold or read events
Tille as actually occurred.
Confabulation: false memories of events not taken place.
Emotions.
BIOLOGICAL ROLE OF EMOTIONS.
The role of emotions in a subjective assessment of the biological motivations and
coming from outside and inside information on a "good-bad."
This and emotions may be negative and positive. Negative emotions can be
expressed in two forms: asthenic (shock,
stupor, fear) and sthenic (fury, rage). Any motivation, getting emotional, updated,
which plays a primary role in the motivational needs.
Theory of emotions.
Freud's theory: emotions - is increasing or decreasing feelings
discomfort in the depths of the brain and its subcortical structures. They
represent a product comparison with the perception of desire, and if
the comparison is satisfactory, there is a positive emotion,
if not - is negative. He made no attempt to link his theory to specific neural
structures.
James-Lange theory: after the perception of a stimulus there autonomic responses,
which are then perceived felt
as a feeling of comfort or discomfort (we are sad because we cry,
angry because it strikes, we are afraid, because I shudder). Some moments later the
theory was confirmed experimentally, but
general theory was not supported.
Cannon-Bard theory: the perception of events nerve impulses
first pass through the thalamus, where the split: the cortex and hypothalamus.
Cortical centers provide a subjective physiological
assessment of perceived and hypothalamic - vegetative reactions.
Emotional stress and psychosomatic disorders.
Emotional strain or emotional stress can be
the cause of many violations in the central nervous system.
- Neuroses. Disruption of higher nervous activity appears neurosis.
This condition can cause the experimentally by applying a very strong
conditional or unconditional stimuli in the development of subtle and complex
forms of differentiation, with prolonged use brake lights,
during the rapid transition from brake to the positive conditioned stimulus, and
alteration of the dynamic stereotype in life-threatening conditions.
Experimental neurosis takes place in several phases:
1. Equalization phase - roughly equal to the reflex response to
different in strength stimuli.
2. Paradoxical phase - inversion relation between the strength of the stimulus and
the magnitude of the conditioned reflex
3. Drug phase - a sharp weakening of response as a strong,
and to weak stimuli.
4. Ultraparadoxical phase - is not always observed and is that the positive
conditioned stimuli cause a braking effect, and cause the brake a positive
conditioned response.
Neurotic disorders may be caused by some physical disorders.
The depth and duration of neurotic disorders depends on the type of
GNI, caused by the reasons and duration of its validity.
- Psychosomatic disorders. Prolonged emotional stress can cause physical
disorders. In this regard,
well known to occur on the basis of emotional stress, hyperthyroidism, peptic
ulcer, hypertension, acute
myocardial ischemia (angina or heart attack), cerebrovascular accidents. The basis
for these diseases lie neotreagirovannye emotions: mostly restrained sthenic
negative (anger, rage).
VIOLATIONS emotional sphere.
Emotional lability - sometimes is one of the characteristics
characteristics of types of GNI, or temperament. Often associated with the overall
high lability of the CNS. Characterized by emotional instability, abrupt mood
swings from despair to euphoria, depression, panic from the aggression. Especially
violations of emotions expressed by some
mental disorders (agitation). Often accompanied by neurotic
violations, especially neurasthenia.
Emotional stupidity - is often a companion of mental illness. Sometimes the
earliest symptom of schizophrenia. Indifferent to their fate and the fate of loved
ones, coldness, lack of initiative. Can be observed as well in some neurotic
disorders.
Euphoria - elevated mood, joy, contentment. As pathology is treated in the absence
of objective reasons for such
state. May be a symptom of intermittent insanity, as well as some forms of
dementia. Often accompanies drug intoxication.
Depression - decreased mood, sadness, hopelessness. As
symptom is often accompanied by a circular psychoses, schizophrenia, affective
psychoses and somatogenic and the vast majority of neurotic disorder:
neurasthenia and other nervous disorders.
Speech.
Speech - a product of nature and the second signal system. It operates with
concepts - abstract symbols of concrete objects and phenomena. These verbal
(verbal) may be oral (sound analyzer), writing (visual analyzer). Special kind of
speech - speech deaf blind, speech and writing - in these cases
analyzers are used unusual for speech.
There is also the inner speech of thought "to myself, which, however,
may be accompanied by ideomotor movements of speech organs.
In the formation of centers of speech right and left hemispheres uneven: the centers
are located in the left hemisphere in the areas of Broca and Wernicke,
and are the centers of the oral and graphic language. If the damage these
centers observed in the corresponding verbal agnosia (neuznavanie
spoken or written language).
Thinking.
Thinking - the highest form of reflection and cognition of objective reality, man,
the establishment of internal relationships between objects and
phenomena of the world.
Thinking up of operations analysis and synthesis.
In thinking relevant comparison operations (establishment
similarities or differences), synthesis (combining into groups based on
major general), abstraction (the exclusion of incidental and inconsequential in the
phenomenon), specificity (display mechanism or phenomenon in
example of a specific example).
The most ancient kind of thinking - visual-efficient, which
characteristic and the higher animals. To implement the necessary set of real
objects that the animal must be seen (for example,
Monkey pours a bucket of water and puts out the fire to get food -
All these items are present in her field of vision).
Thinking up of complex judgments (approval or denial of any phenomenon,
dependence, mechanism) on the basis of which is formed by inference as a logical
consequence of comparing
judgments.
Thinking is divided into inductive (from individual private opinions to the general)
and deductive (based on the general provisions of the emerging private findings
and patterns).
Thinking is divided into a concrete shape, when a person operates primarily signals
an alarm system and an abstract logic, when a person operates primarily images of
two signaling systems.
Different people have these two kinds of thinking are presented in different
proportions. For people art warehouse is more characteristic of the first
for the "thinkers" - the second. This, however, does not mean that a
have advantages. Great importance here is the predominance of right or left
hemisphere. Right more focused on images and
perception of specific stimuli, a signal system, whereas
left - the perception of the abstract notion of 2 signaling system.
BREACH OF THINKING.
Dementia. With dementia, thinking mainly of concrete imagery,
but this is due not predominance of a hemisphere
just immaturity of the second signal system. Dementia is
congenital (genetic abnormality), acquired during childbirth
(Birth trauma, asphyxia at birth), acquired in early childhood
(Cerebral palsy or other Neuroinfections) and acquired at a later age (trauma,
degenerative disease
nervous system syphilis, neuroinfections, alcoholism itoksikomanii,
chronic toxicity, endocrine disorders, atherosclerosis of cerebral vessels, etc.).
Paranoia. The emergence of ideas and conclusions, which are given undue weight,
a kind of l'idee fixe. (Perpetual motion machine, the invention of bicycles, the
reformation of society, etc.).
Paranoid (delirium). The appearance of distorted reasoning, on nothing
based suspicion, often directed at others or close
(Delusions of persecution, prejudice, the influence of hypnosis, etc.).
Paraphrenia. The emergence of reasoning, in principle, impossible, fantastic and
fabulous (contact with aliens, devils, etc.) ..
Illustrative material: L-OM1-17
REFERENCES:
Main:
1. Human Physiology, VM Pokrovsky., GF Korotko, M., 2004.
2. Guide to practical exercises on normal physiology. KV Sudakov, AV Kotov, M.,
2002.
3. Guidance on general and clinical physiology. V. Filimonov, MIA, 2002, 957 p.
4. Normal physiology, ed. KV Sudakov, M., 2000.
5. Aghajanian, NA, Tel LZ, Tsirkin VI, Chesnakova SA Physiology
rights. St. Petersburg, Sotis, 2000, 528 pp.
More:
1. Physiology of higher nervous activity with the basics of neuroscience.
Author: Shul'govskil VV, 2003, 464 pp.
2. Physiology of Higher Nervous Activity and sensory systems. Batuev IK, St.
Petersburg, 2004, 356.
3. Alexandrov YI and other basics of Psychophysiology. Moscow, Infra-M, 1998.,
431s.
4. Anatomy, physiology and hygiene in tables and diagrams. Manual. 1991.
5. "Fundamentals of human physiology," 1 and Volume 2, BI Tkachenko, St.
Petersburg, 1994.
6. Atlas of the normal physiology of AV Korobkov, SA Chesnokov, Moscow,
High School, 1987.
7. Handbook of physiological and laboratory parameters of healthy humans. AA
Utepbergenov, 1995.
8. Human Physiology. Ed. M. Pokrovsky, GF Korotko, in two volumes, Moscow,
2001, 368 pp.
9. Physiology of higher nervous activity. Voronin, LM: [Textbook. Manual for
Biology. specials. University comrade-M. Vyssh. School, 1979
10. Delgado, H. Brain and consciousness. Moscow, Mir, 1971., 264s.
11. Alexandrov YI and other basics of Psychophysiology. Moscow, Infra-M,
1998., 431s.
Test questions (feedback):
1. What types of memory, you know
2. Explain the mechanism of attention
3. What are the different pathological types of perception?
4. With the help of a table is determined by the ability to concentrate?
5. What is a short-term memory and what is its mechanism?
Medical University of Astana
Department of Physiology
Lecture № 18.
Theme Lecture: Physiology of work.
Purpose: To study the mechanisms of the behavioral act from the standpoint of
the theory of functional systems, PK Anokhin, to form a view on the classification
of labor on the severity and intensity, to learn how to explain the work of
functional systems.
Abstracts of lectures:
The process of physiological regulation is the basis of self-gratification needs of a
living organism. Needs are met through the activities of control systems - the
nervous and endocrine.
To meet their needs in terms of changes of the environment the body needs:
1. set specific tasks;
2. achieve the intended result.
According to the teachings Anokhin, it is a useful result is a factor in determining
the behavior and functional system (Fuss). Fuss is formed as a group of
interconnected neurons that provide useful outcomes. The task of the Fuss is
identification and evaluation of results.
Fuse components are:
1 - a useful result,
2 - receptors
3 - the nerve center,
4 - actuators
5 - ways of feedback messages result of the action.
Accountability of the executive bodies to the center provides evaluation results,
and amendments to the work of Fuss, if the result is not reached.
The doctrine of the functional system, created by Anokhin, suggests
staging and conditionality of purposeful activity.
Functional system - not a rigid anatomical and physiological education. It is
created with the participation of the cerebral cortex just
time when the development is targeted act
adaptive behavioral activity.
The basis of the formation of a functional system is the dominant
motivation, which is painting the emotionally negative, forms
direction and is the primary mechanism in the afferent synthesis.
Afferent synthesis - a kind of processing of the initial conditions of which involved
the dominant motivation (urgent need), situational afferentation (evaluation
environments in terms of capacity to meet current needs), memory (experience
how satisfied this need earlier and how to meet) and pad afferentation (estimate the
possibility of starting
action, a signal to it).
Decision point occurs with the participation of associative centers.
In this stage the program of action.
Next begins the action itself, which is constantly monitored
acceptor action by afferent feedback. Contact afferentation provides material for
permanent compare the results of
and programs of action. If the comparison result unsatisfactory
- The action continues, and emotional state is not changed.
The action continues as long as the result of the comparison does not prove
satisfactory. Then the emotional state is replaced by
positive motivation ceases to dominate and functional
system for this particular action falls.
PARAMETERS OF RESULT
Goal-directed behavior is based on a biological motivation (common to humans
and animals) and social motivation (mainly typical of the man and only in its
infancy
able to animals).
Biologically determined goal-directed behavior has
the basis of unconditional reflexes, and is divided into:
- Edible
- Defensive
- Sexual and parental.
Socially determined goal-directed behavior is based on
higher mental functions and is divided into:
- Career
- Social behavior
- Training
- Play behavior, etc.
• Physiology - this is an experimental science. It uses two basic methods:
observation and experiment.
Observation - the basic method of learning about and used in any scientific study.
Its disadvantage is the passivity of the researcher who can find only the outward
aspect of the phenomenon, for example - work (function) of the body. The
mechanism of regulation of the body can be determined only empirically.
The experiment allows the researcher to create certain conditions in which clarified
the quantitative and qualitative characteristics of the sludge that phenomenon.
The experiment can be acute or chronic. Acute experience (vivisection) allows in a
short time to study any regulatory mechanism, triggered in extreme situations for
the test organism. Chronic experiment allows for a long time to investigate the
mechanisms of regulation in the normal interaction of organism and environment.
In animal experiments using surgical techniques - extirpation (removal) or an
organ transplant, implantation of electrodes and sensors. Objective method is the
method of telemetry, capable of detecting the parameters of the process or
phenomenon from a distance.
Experimental studies in recent years carried out using sophisticated optical,
electronic, electronic equipment, allowing simultaneously explore dozens of
functions, their change in the interaction, ie complex.
Processing of the resulting data set is using the methods of mathematical statistics
and computer technology.
The nervous system consists of the central and peripheral divisions. CNS includes
the brain and spinal cord, and PNS - it's all nerves, and nodes that lie outside the
CNS.
A distinction is also the somatic and autonomic nervous system. The first regulates
the function of skeletal muscles and sense organs. The second regulates the
function of internal organs and glands.
Allocation of above-mentioned departments in the nervous system is arbitrary,
convenient for studying a certain logical sequence. In fact, the nervous system is
anatomically and functionally a unit, the unit basis of which are neurons.
The nervous system is the leading physiological system of the organism, the main
control system. This is confirmed by the fact that the National Assembly of the
fetus begins to function long before his birth (Science News, № 16, 1984).
Function of the nervous system can be divided into two types: high and low.
Lower neural activity is the process of regulation of organs and systems in the
body.
Higher nervous activity includes those functional mechanisms of the brain that
provides the body with the appropriate contact with the environment. Higher
functions are the basis of human mental activity, the formation of personality traits:
the temperament, character, abilities, needs and interests. Higher nervous activity
requires prompt and adequate changes in the operation of the internal organs.
Consequently, the higher and lower nervous activity overlap and should be
considered in close harmonious unity.
• Most animals and humans is manifested in the form of functions and
physiological regulations.
Function is a specific activity of cells, tissues and organs. For example, the
function of muscle is reduced, glands - secretion, neurons - the generation and
conduction of impulses. Due to changes in the functions the body adapts to
changes in living conditions.
All functions can be divided into:
1) Somatic (animals), which are implemented through the activities of skeletal
muscles innervated by the SNA;
2) vegetative (plant) that are associated with metabolism, growth and reproduction.
They are implemented at the expense of the internal organs innervated by ANS.
Physiological act - a complex process that is carried out with the participation of
various body systems (physiological acts breath, digestion, extraction, respiration,
etc.). For example, the physiological act of digestion involves the excitation of
sensory divisions of the CNS (visual, olfactory, gustatory, tactile), motor centers
(extraction, processing and cooking), the secretory apparatus of the gastrointestinal
tract (digestive juices), smooth muscles of the digestive tract (motility, peristalsis) ,
and intestinal epithelia (absorption). Thus, the act of digestion provided a
manifestation of complex and multiple functions at the cellular, tissue, organ and
system levels, which are included in the functional system (Fuss) and provide
useful outcomes.
"All regulated flows through the cleared beds, making his circuit in accordance
with the law and under its protection."
I. Ilf and Petrov "Golden Calf"
• All cells and tissues of a living organism under the influence of stimuli moving
from a state of relative physiological rest in the state of activity (excitation). The
highest degree of activity observed in nerve and muscle tissue.
The main properties of excitable tissues are: I. excitability, II conductance, III
refractoriness and Lability, are associated with one of the most common properties
of a living - irritability.
Changes in the environment or the body is called irritants, and their effects irritation.
By the nature of the stimuli are: mechanical, chemical, electrical, thermal.
On the biological basis of stimuli are divided into:
1. adequate, which are perceived by the relevant specialized receptors (eyes - the
light, the ear - the sound, the skin - a pain, temperature, touch, pressure, vibration);
2. inadequate, which specialized receptors are not adapted, but take them with
excessive force and duration (shock - an eye - light).
The most general, adequate and natural stimulus for all cells and tissues is a
nervous impulse.
The main physiological properties of nervous tissue (excitability, conduction,
refractoriness and Lability) characterize the functional status of the human nervous
system, determine his mental processes.
• I. Excitability - the ability of tissue to respond to the stimulus appearance of the
excitation process with a change in physiological properties.
Kollichestvennoy measure of excitability is the threshold of excitation, ie
minimum value of the stimulus that can trigger a reaction of tissues.
Stimulus smaller force called the subliminal and more - supraliminal.
Excitability is, first and foremost, a change of metabolism in tissue cells. Change
in metabolism is accompanied by a transition through the cell membrane of
negatively and positively charged ions, which alter the electrical activity of cells.
The potential difference at rest between the inner cell contents and cell membrane,
is 50-70 mV (millivolt) is resting membrane potential.
The basis for this state of the cell is selective permeability of the membrane with
respect to the ions K and Na. Ions Na, located in the extracellular medium through
the membrane into the cells the way closed, and to easily penetrate through the
pores of the cell membrane from the cytoplasm of cells in tissue fluid. As a result,
in the cytoplasm are negatively charged ions on the membrane surface and
accumulate positively charged ions K and Na.
When excited by the cell permeability of Na ions increases sharply, and they rush
to the cytoplasm, lowering the resting potential to zero and then increasing the
potential difference of opposite values to 80-110 mV. Such short-term (0,0040,005 sec) changes the potential difference is called the action potential (spike)
Engl. spike - the tip.
Following this, the disturbed balance of ions is restored. To do this, there is a
special cellular mechanism - sodium-potassium pump, which provides an active
"pumping" Na from the cell and forcing "it to. Thus, there are 2 types of ions
across the cell membrane:
1 - passive ion transport in the gradient of ion concentration;
2 - active ion transport against the concentration gradient, carried out "the sodiumpotassium pump" from the energy of ATP.
Conclusion: The stimulation of nerve cells associated with changes in metabolism
and is accompanied by the advent of electric potential (nerve impulse).
• Conductivity - the ability of tissue to carry out a wave of excitation - bioelectric
impulses.
To ensure the homeostatic unity of all body structures (cells, tissues, organs, etc.)
should be able to spatial interaction. Propagation of a disturbance of its place of
origin to the executive bodies - one of the main ways of such interaction. Arising
out of place causing irritation of the action potential causes irritation of adjacent,
unexcited parts of the nerve (or muscle) fibers. Due to this phenomenon creates a
wave of action potential action current, which extends along the entire length of
the nerve fibers. In Remak's fiber stimulation is carried out with some damping damping rate, and in myelinated nerve fibers - without damping. Conduction of
excitation is also accompanied by changes in metabolism and energy.
• III. Refractoriness - temporary reduction in excitability of tissue that occurs when
a potential action. At this point, repeated stimulation did not cause a response
(absolute refractoriness). It lasts no more than 0.4 milliseconds, and then comes a
phase of relative refractory when irritation can cause a weak reaction. This phase
gives way to a phase of increased excitability - supernormal.
Such dynamics of excitability due to processes of change and restore the balance of
ions on the cell membrane.
Professor NE Vvedensky investigated the characteristics of these processes and
found that the excitable tissue may respond to different number of action potentials
at a frequency of stimulation. He called this phenomenon lability (functional
mobility).
Lability - the property of excitable tissues to play the maximum number of action
potentials per unit time.
Maximum lability - in nervous tissue. Frequency stimulation causing maximal
response is called an optimal (Latin optimum - the best), and causes inhibition of
the reaction - pessimal (Latin pessimum - the worst).
* Nerve fiber - up to 1000 pulses / sec, the muscle - 200-250 pulses / sec., Synapse
- to 100-125 pulses / sec.
Pessimum - active tissue response aimed at protecting it from excessive
stimulation. This is one of the forms of inhibition. Excitation and inhibition is
opposite to the value of self-regulatory processes that establish a middle-level
relationships of the organism with the environment
Illustrative material: L-OM1-18
REFERENCES:
Main:
1. Human Physiology, VM Pokrovsky., GF Korotko, M., 2004.
2. Guide to practical exercises on normal physiology. KV Sudakov, AV Kotov, M.,
2002.
3. Guidance on general and clinical physiology. V. Filimonov, MIA, 2002, 957 p.
4. Normal physiology, ed. KV Sudakov, M., 2000.
5. Aghajanian, NA, Tel LZ, Tsirkin VI, Chesnakova SA Physiology
rights. St. Petersburg, Sotis, 2000, 528 pp.
More:
12. Physiology of higher nervous activity with the basics of neuroscience.
Author: Shul'govskil VV, 2003, 464 pp.
13. Physiology of Higher Nervous Activity and sensory systems. Batuev IK, St.
Petersburg, 2004, 356.
14. Alexandrov YI and other basics of Psychophysiology. Moscow, Infra-M,
1998., 431s.
15. Anatomy, physiology and hygiene in tables and diagrams. Manual. 1991.
16. "Fundamentals of human physiology," 1 and Volume 2, BI Tkachenko, St.
Petersburg, 1994.
17. Atlas of the normal physiology of AV Korobkov, SA Chesnokov, Moscow,
High School, 1987.
18. Handbook of physiological and laboratory parameters of healthy humans. AA
Utepbergenov, 1995.
19. Human Physiology. Ed. M. Pokrovsky, GF Korotko, in two volumes, Moscow,
2001, 368 pp.
20. Physiology of higher nervous activity. Voronin, LM: [Textbook. Manual for
Biology. specials. University comrade-M. Vyssh. School, 1979
21. Delgado, H. Brain and consciousness. Moscow, Mir, 1971., 264s.
22. Alexandrov YI and other basics of Psychophysiology. Moscow, Infra-M,
1998., 431s.
Test questions (feedback):
1. What are the main stages of the functional system Anokhin PK
2. Classified as work on the severity of
3. Give an example of passive adaptation to changing environmental conditions
4. By what kind of adaptation may include the flight of birds in the warmer climes?