How does the sensory system transmit information to the brain. Sensory systems: functions, structure and main processes occurring in sensory systems

General information

Adhering to the cognitive approach to the description of the psyche, we represent a person as a kind of system that processes symbols in solving its problems, then we can imagine the most important feature of a person's personality - the sensory organization of the personality.

Sensory organization of personality

The sensory organization of the personality is the level of development of individual systems of sensitivity and the possibility of their association. The sensory systems of a person are his sense organs, as if receivers of his sensations, in which sensation is transformed into perception.

Every receiver has a certain sensitivity. If we turn to the animal world, we will see that the predominant level of sensitivity of any species is a generic trait. For example, at bats developed sensitivity to the perception of short ultrasonic pulses, dogs have olfactory sensitivity.

The main feature of the sensory organization of a person is that it develops as a result of all his life path. The sensitivity of a person is given to him at birth, but its development depends on the circumstances, desire and efforts of the person himself.

What do we know about the world and about ourselves? Where do we get this knowledge from? How? The answers to these questions come from the depths of centuries from the cradle of all living things.

Feel

Sensation is a manifestation of the general biological property of living matter - sensitivity. Through sensation there is a psychic connection with the external and inner world. Thanks to sensations, information about all phenomena outside world delivered to the brain. In the same way, a loop is closed through sensations to receive feedback about the current physical and partly mental state organism.

Through sensations, we learn about taste, smell, color, sound, movement, the state of our internal organs, etc. From these sensations, holistic perceptions of objects and the whole world are formed.

It is obvious that the primary cognitive process takes place in human sensory systems, and already on its basis, cognitive processes that are more complex in their structure arise: perceptions, representations, memory, thinking.

No matter how simple the primary cognitive process, but it is it that is the basis mental activity, only through the "entrances" of sensory systems does the world around us penetrate into our consciousness.

Sensation Processing

After the information is received by the brain, the result of its processing is the development of a response or strategy aimed, for example, at improving physical tone, focusing more on current activities, or setting up for accelerated inclusion in mental activity.

Generally speaking, the response or strategy worked out at any given time is the best choice of the options available to the person at the time of making the decision. However, it is clear that the number of options available and the quality of choice are different for different people and depend, for example, on:

mental properties of personality,

strategies for interacting with others

some of the physical condition,

experience, the availability of the necessary information in memory and the possibility of retrieving it.

degree of development and organization of higher nervous processes etc.

For example, the baby went out naked in the cold, his skin feels cold, perhaps chills appear, he becomes uncomfortable, a signal about this enters the brain and a deafening roar is heard. The reaction to cold (stimulus) in an adult may be different, he will either rush to get dressed, or jump into a warm room, or try to warm himself in another way, for example, by running or jumping.

Improving the higher mental functions of the brain

Over time, children improve their reactions, multiplying the effectiveness of the result achieved. But after growing up, the opportunities for improvement do not disappear, despite the fact that the adult's susceptibility to them decreases. It is in this that "Effekton" sees part of its mission: increasing the efficiency of intellectual activity by training the higher mental functions of the brain.

Effekton's software products make it possible to measure various indicators of the human sensorimotor system (in particular, the Jaguar package contains tests of the time of a simple audio and visual-motor reaction, a complex visual-motor reaction, and the accuracy of perception of time intervals). Other packages of the "Effekton" complex evaluate the properties of cognitive processes of higher levels.

Therefore, it is necessary to develop the perception of the child, and the use of the package "Jaguar" can help you with this.

Physiology of sensations

Analyzers

The physiological mechanism of sensations is the activity of the nervous apparatus - analyzers, consisting of 3 parts:

receptor - the perceiving part of the analyzer (carries out the conversion of external energy into a nervous process)

central part of the analyzer - afferent or sensory nerves

cortical sections of the analyzer, in which the processing of nerve impulses takes place.

Certain receptors correspond to their sections of cortical cells.

The specialization of each sense organ is based not only on the structural features of the receptor analyzers, but also on the specialization of the neurons that make up the central nervous apparatus, which receive signals perceived by the peripheral senses. The analyzer is not a passive receiver of energy; it is reflexively rebuilt under the influence of stimuli.

The movement of stimulus from the outer to the inner world

According to the cognitive approach, the movement of a stimulus during its transition from the external world to the internal one occurs as follows:

the stimulus causes certain changes in energy in the receptor,

energy is converted into nerve impulses

information about nerve impulses is transmitted to the corresponding structures of the cerebral cortex.

Sensations depend not only on the capabilities of the brain and sensory systems of a person, but also on the characteristics of the person himself, his development and condition. With illness or fatigue, a person changes sensitivity to certain influences.

There are also cases of pathologies when a person is deprived, for example, of hearing or sight. If this trouble is congenital, then there is a violation of the flow of information, which can lead to delays mental development. If these children were taught special techniques to compensate for their shortcomings, then some redistribution within the sensory systems is possible, thanks to which they will be able to develop normally.

Properties of sensations

Each type of sensation is characterized not only by specificity, but also has general properties with other types:

quality,

intensity,

duration,

spatial localization.

But not every irritation causes a sensation. The minimum value of the stimulus at which a sensation appears is the absolute threshold of sensation. The value of this threshold characterizes the absolute sensitivity, which is numerically equal to the value inversely proportional to the absolute threshold of sensations. And sensitivity to a change in the stimulus is called relative or difference sensitivity. The minimum difference between two stimuli, which causes a slightly noticeable difference in sensations, is called the difference threshold.

Based on this, we can conclude that it is possible to measure sensations. And in again you come in admiration of amazing delicately working devices - human sense organs or human sensory systems.

Effekton software products allow you to measure various indicators sensory system a person (for example, the "Jaguar" package contains tests of the speeds of a simple audio and visual-motor reaction, a complex visual-motor reaction, the accuracy of time perception, the accuracy of space perception, and many others). Other packages of the "Effekton" complex also evaluate the properties of cognitive processes of higher levels.

Classification of sensations

Five basic types of sensations: sight, hearing, touch, smell and taste - were already known to the ancient Greeks. At present, ideas about the types of human sensations have been expanded; about two dozen different analyzer systems can be distinguished, reflecting the impact of external and internal environment to receptors.

Sensations are classified according to several principles. The main and most significant group of sensations brings information from the outside world to a person and connects him with the external environment. These are exteroceptive - contact and distant sensations, they arise in the presence or absence of direct contact of the receptor with the stimulus. Sight, hearing, smell are distant sensations. These types of sensations provide orientation in the nearest environment. Taste, pain, tactile sensations - contact.

According to the location of receptors on the surface of the body, in muscles and tendons, or inside the body, they are distinguished, respectively:

exteroception - visual, auditory, tactile and others;

proprioception - sensations from muscles, tendons;

interoception - feelings of hunger, thirst.

In the course of the evolution of all living things, sensitivity has undergone changes from the most ancient to the modern. So, distant sensations can be considered more modern than contact ones, but in the structure of the contact analyzers themselves, one can also reveal more ancient and completely new functions. So, for example, pain sensitivity is more ancient than tactile.

Such classification principles help to group all kinds of sensations into systems and see their interaction and connections.

Types of sensations

Vision, hearing

Consider different kinds sensations, bearing in mind that vision and hearing are the most well studied.

Sensory systems are considered to be components of the NN, which is involved in the perception of information from the outside world, its transmission into the brain and analysis. Receiving data from environment and his body - a necessary factor for the life of the individual.

This analyzer is one of the most important components of the central nervous system, involving sensory receptors, nerve fibers that carry information to the brain and its departments. Then they begin to process and analyze the data.

General information

Each analyzer implies the presence of peripheral receptors, conducting ducts and switching nuclei. In addition, they have a special hierarchy, have several levels of step-by-step data processing. At the lowest level of such perception, primary sensory neurons are involved, located in special sensory organs or ganglia. They help conduct excitation from peripheral receptors to the CNS. Peripheral receptors are receptive highly specialized neoplasms that are able to perceive, transform and transmit external energy to primary sensory neurons.

Device principle

To understand how the sensory system functions, it is necessary to learn about its structure. There are 3 of its components:

• peripheral (receptors);
• conductive (methods of excitation);
• central (cortical neurons that analyze the stimulus).

The beginning of the analyzer are receptors, and the end - neurons. Parsers should not be confused with . The former lack an effector part.

The principle of operation of sensor systems

General rules for the functioning of analyzers:

• Transformation of irritation into a frequency code of impulse signals. Is the universal functioning of any receptor. In each of them, processing will begin with changes in the characteristics of the cell membrane. Under the influence of a stimulus, controlled ion channels open inside the membrane. They propagate through these channels and depolarization occurs.
• Topical match. The flow of information in the transmission structure must correspond to the essential indicators of the stimulus. This may mean that its key indicators will be encoded as a stream of impulses and the NS creates an image that will resemble a stimulus.
• Detection. It is a branch of qualitative symptoms. Neurons begin to respond to specific manifestations of the object and not perceive others. They are characterized by abrupt transitions. Detectors add meaning and identity to the fuzzy impulse. In different pulses, they highlight similar parameters.
• Distortion of information about the analyzed object at all levels of excitation.
• Receptor specificity. Their susceptibility is maximum to a specific type of stimulus with different strength.
• Feedback between structures. Subsequent structures are able to change the state of the previous ones, the characteristics of the excitation flow coming to them.

visual system

Vision is a multi-element process that begins with the projection of an image onto the retina. After the photoreceptors are excited, then they are transformed in the neural layer, and finally a decision is made about the sensory image.

The visual analyzer involves certain departments:

• Peripheral. An additional organ is the eye, where receptors and neurons are concentrated.
• Conductor. The optic nerve, which represents the fibers of 2 neurons and transmits data to 3. Some of them are located in the midbrain, the second - in the intermediate.
• Cortical. 4 neurons are concentrated in the cerebral hemispheres. This formation is the primary field or core of the sensory system, the purpose of which will be the formation of sensations. Near it is a secondary field, the purpose of which is the recognition and processing of a sensory image, which will become the foundation of perception. The subsequent transformation and connection of data with information from other analyzers is observed in the lower parietal region.

auditory system

The auditory analyzer encodes acoustic images and determines the possibility of orientation in space due to the evaluation of the stimulus. The peripheral parts of this analyzer represent the organs of hearing and the phonoreceptors located in the inner ear. Based on the formation of analyzers, the nominative purpose of speech appears - the association of things and names.

The auditory analyzer is considered one of the most important as it becomes a means of communication between people.

outer ear

The external ear canal conducts sound impulses to the tympanic membrane, which separates the outer ear from the middle ear. It is a thin partition and looks like an inwardly oriented funnel. After exposure to sound impulses through the outer ear, the membrane oscillates.

Middle ear

It contains 3 bones: the hammer, anvil and stirrup, which gradually convert the oscillatory impulses of the tympanic membrane to the inner ear. The handle of the malleus is woven into the membrane itself, and the 2nd part is connected to the anvil, which in turn directs the impulse of the stirrup. It transmits impulses of smaller amplitude, but more intense. Inside the middle ear are 2 muscles. The stirrup fixes the stirrup, preventing it from moving, while the straining one contracts and increases the tension. By contracting approximately 10 ms later, these muscles prevent congestion in the inner ear.

The structure of the snail

The inner ear contains the cochlea, which is a bony spiral with dimensions of 0.04 mm in width and 0.5 mm at the top. This channel is divided by 2 membranes. At the top of the cochlea, each of these membranes is connected. The upper one will overlap with the lower channel through an oval hole using a tympanic ladder. They are filled with perilymph, similar in consistency to cerebrospinal fluid. In the middle of the 2 channels is membranous, which is filled with endolymph. In it, on the main membrane, there is an apparatus that perceives sounds and includes receptor cells that convert mechanical impulses.

Olfactory

This analyzer perceives and analyzes chemical stimuli that are located in the outside world and act on the olfactory system. The process itself is perception through special bodies any characteristics (aromas) of various substances.

The olfactory system in an individual is expressed by the epithelium, which is located at the top of the nasal cavity and includes sections of the lateral shell and septum on each side. It is enveloped in olfactory mucus and includes special chemoreceptors, supporting and basal cells. The area of ​​respiration has free endings of sensory fibers that react to aromatic substances.

Contains the following departments:

• Peripheral. Assumes olfactory organs and epithelium, which contain chemoreceptors and nerve fibers. There are no common elements in the paired conducting ducts, therefore damage to the olfactory centers on one side is likely.
• Secondary data transformation center. Assumes the presence of primary centers of smell and an auxiliary organ.
• Central. The final instance of data processing, which is located in the forebrain.

Somatosessory

The somatosensory analyzer provides neural processes that process sensory data throughout the body. Somatic perception is opposed to specific sensations that involve visual and auditory function, aroma, taste, and coordination.

There are 3 physiological varieties of such sensations:

• mechanoreceptive, which include touch and orientation (stimulated by mechanical movements of certain tissues in the body);
• thermoreceptive, manifested under the influence of temperature indicators;
• painful, formed under the influence of any factors that damage tissues.

There are other criteria for separating such sensations:

• exteroceptive, which appear in the process of irritation of the receptor located on the body;
• proprioceptive, which are related to physical condition(body position, muscle and tendon tone, level of pressure on the feet and sense of coordination).

Visceral sensations are associated with the state of the body. Deep feelings come from deep tissues. These include predominantly "deep" pressure, pain and vibration.

The essence of perception

It is a more confusing psycho-emotional process regarding sensation. Perception is a holistic image of objects and events that arise as a result of the synthesis of sensations. During this process, the highlighting of the most significant and important characteristics of the subject is noted with separation from the insignificant for such a case and the correlation of what is perceived with the experienced experience. Any perception involves an active functional component (probing, eye activity when looking at, etc.) and complex analytical work of the brain.

Perception can manifest itself in the following forms: conscious, subthreshold and extrasensory.

Specialists mainly study the study of the conscious, having advanced far in understanding the mechanisms and patterns of this process. Its study is based on data from psychophysiological studies.

The sensory system is a complex of peripheral and central parts of the central nervous system that are responsible for receiving impulses. various images from the outside world or from your own body.

This structure suggests the presence of receptors, neuronal ducts and divisions in the brain. They are responsible for converting outgoing signals. The most famous are visual, auditory, olfactory, somatosensory analyzers. They make it possible to differentiate between different physical characteristics(temperature indicators, taste, sound vibrations or pressure). Sensory analyzers are the most important elements of the individual's nervous system. They take an active part in the processing of data from external environment, its transformation and analysis. Receiving information from the environment will become a necessary condition for life.

visual sensory system. Organ of hearing and balance. Analyzers of smell and taste. Skin sensory system.

The human body as a whole is a unity of functions and forms. Regulation of the body's life support, mechanisms for maintaining homeostasis.

Topic for self-study: The structure of the eye. Ear structure. The structure of the tongue and the location of the zones of sensitivity on it. The structure of the nose. Tactile sensitivity.

Sense organs (analyzers)

A person perceives the world around him through the sense organs (analyzers): touch, sight, hearing, taste and smell. Each of them has specific receptors that perceive certain kind irritation.

Analyzer (sense organ)- consists of 3 departments: peripheral, conductor and central. Peripheral (perceiving) link analyzer - receptors. They convert the signals of the outside world (light, sound, temperature, smell, etc.) into nerve impulses. Depending on the mode of interaction of the receptor with the stimulus, there are contact(skin receptors, taste receptors) and distant(visual, auditory, olfactory) receptors. conductor link analyzer - nerve fibers. They conduct excitation from the receptor to the cerebral cortex. Central (processing) link analyzer - a section of the cerebral cortex. Violation of the functions of one of the parts causes a violation of the functions of the entire analyzer.

There are visual, auditory, olfactory, gustatory and skin analyzers, as well as a motor analyzer and a vestibular analyzer. Each receptor is adapted to its specific stimulus and does not perceive others. Receptors are able to adapt to the strength of the stimulus by reducing or increasing sensitivity. This ability is called adaptation.

visual analyzer. Receptors are excited by light quanta. The organ of vision is the eye. It consists of an eyeball and an auxiliary apparatus. Auxiliary device represented by eyelids, eyelashes, lacrimal glands and muscles of the eyeball. Eyelids formed by folds of skin lined from the inside with a mucous membrane (conjunctiva). Eyelashes protect the eye from dust particles. Lacrimal glands located in the outer upper corner of the eye and produce tears that wash the anterior part of the eyeball and enter the nasal cavity through the nasolacrimal canal. Muscles of the eyeball set it in motion and orient it towards the object in question.

Eyeball located in the orbit and has a spherical shape. It contains three shells: fibrous(outer), vascular(middle) and mesh(internal) and inner core, consisting of lens, vitreous body And aqueous humor anterior and posterior chambers of the eye.

The posterior part of the fibrous membrane is a dense opaque connective tissue albuginea (sclera), front - transparent convex cornea. The choroid is rich in vessels and pigments. It distinguishes actually choroid(rear part), ciliary body And rainbow shell. The main mass of the ciliary body is the ciliary muscle, which changes the curvature of the lens with its contraction. Iris ( iris) has the form of a ring, the color of which depends on the amount and nature of the pigment it contains. There is a hole in the center of the iris pupil. It can narrow and expand due to the contraction of the muscles located in the iris.

The retina is divided into two parts: back- visual, perceiving light stimuli, and anterior- blind, not containing photosensitive elements. The visual part of the retina contains light-sensitive receptors. There are two types of visual receptors: rods (130 million) and cones (7 million). sticks are excited by weak twilight light and are not able to distinguish color. cones excited by bright light and able to distinguish color. The sticks contain red pigment - rhodopsin, and in cones - iodopsin. Directly opposite the pupil there is yellow spot - the place of best vision, which consists only of cones. Therefore, we see objects most clearly when the image falls on the macula. Toward the periphery of the retina, the number of cones decreases, the number of rods increases. On the periphery are only sticks. The place on the retina where the optic nerve exits is devoid of receptors and is called blind spot.

Most of the cavity of the eyeball is filled with a transparent gelatinous mass, forming vitreous, which maintains the shape of the eyeball. lens is a biconvex lens. Its back is adjacent to the vitreous body, and the front is facing the iris. With the contraction of the muscle of the ciliary body associated with the lens, its curvature changes and the rays of light are refracted so that the image of the object of vision falls on the yellow spot of the retina. The ability of the lens to change its curvature depending on the distance of objects is called accommodation. If accommodation is disturbed, there may be myopia(the image is focused in front of the retina) and farsightedness(the image is focused behind the retina). With myopia, a person sees indistinctly distant objects, with farsightedness, near ones. With age, the lens thickens, accommodation deteriorates, and farsightedness develops.

On the retina, the image is inverted and reduced. Due to the processing in the cortex of information received from the retina and receptors of other sense organs, we perceive objects in their natural position.

auditory analyzer. The receptors are excited by sound vibrations in the air. The organ of hearing is the ear. It consists of the outer, middle and inner ear. outer ear consists of the auricle and ear canal. auricles are used to capture and determine the direction of sound. External auditory canal begins with the external auditory opening and ends blindly tympanic membrane which separates the outer ear from the middle ear. It is lined with skin and has glands that secrete earwax.

Middle ear It consists of the tympanic cavity, the auditory ossicles and the auditory (Eustachian) tube. tympanic cavity filled with air and connected to the nasopharynx narrow passage -auditory tube, through which the same pressure is maintained in the middle ear and the space surrounding the person. auditory ossicles - hammer, anvil And stirrup - connected to each other movably. They transmit vibrations from the eardrum to the inner ear.

inner ear consists of a bony labyrinth and a membranous labyrinth located in it. Bone labyrinth contains three sections: vestibule, cochlea and semicircular canals. The cochlea belongs to the organ of hearing, the vestibule and semicircular canals - to the organ of balance (vestibular apparatus). Snail- bone canal, twisted in the form of a spiral. Its cavity is divided by a thin membranous septum - the main membrane on which receptor cells are located. The vibration of the cochlear fluid irritates the auditory receptors.

The human ear perceives sounds with a frequency of 16 to 20,000 Hz. Sound waves travel through the external auditory canal to the eardrum and cause it to vibrate. These vibrations are amplified (almost 50 times) by the auditory ossicles and are transmitted to the fluid in the cochlea, where they are perceived by the auditory receptors. The nerve impulse is transmitted from the auditory receptors through the auditory nerve to the auditory zone of the cerebral cortex.

vestibular analyzer. The vestibular apparatus is located in the inner ear and is represented by the vestibule and semicircular canals. threshold consists of two bags. Three semicircular canals located in three mutually opposite directions corresponding to the three dimensions of space. Inside the sacs and channels there are receptors that are able to perceive fluid pressure. The semicircular canals receive information about the position of the body in space. The sacs perceive deceleration and acceleration, changes in gravity.

Excitation of the receptors of the vestibular apparatus is accompanied by a number of reflex reactions: a change in muscle tone, muscle contraction, contributing to the straightening of the body and maintaining the posture. Impulses from the receptors of the vestibular apparatus through the vestibular nerve enter the central nervous system. The vestibular analyzer is functionally connected with the cerebellum, which regulates its activity.

Taste analyzer. Taste buds are irritated chemicals, dissolved in water. The organs of perception are taste buds- microscopic formations in the mucous membrane of the oral cavity (on the tongue, soft palate, posterior pharyngeal wall and epiglottis). Receptors specific to the perception of sweet are located on the tip of the tongue, bitter - on the root, sour and salty - on the sides of the tongue. With the help of taste buds, food is tested, its suitability or unsuitability for the body is determined, when they are irritated, saliva and gastric and pancreatic juices are released. The nerve impulse is transmitted from the taste buds through the taste nerve to the taste zone of the cerebral cortex.

Olfactory analyzer. The olfactory receptors are irritated by gaseous chemicals. The organ of perception is the perceptive cells in the nasal mucosa. The nerve impulse is transmitted from the olfactory receptors through the olfactory nerve to the olfactory zone of the cerebral cortex.

Skin analyzer. Skin contains receptors , perceiving tactile (touch, pressure), temperature (thermal and cold) and pain stimuli. The organs of perception are the perceiving cells in the mucous membranes and skin. The nerve impulse is transmitted from the tactile receptors through the nerves to the cerebral cortex. With the help of tactile receptors, a person gets an idea of ​​the shape, density, temperature of bodies. Tactile receptors are most found on the fingertips, palms, soles of the feet, and tongue.

motor analyzer. Receptors are excited during contraction and relaxation of muscle fibers. The organs of perception are the perceiving cells in the muscles, ligaments, on the articular surfaces of the bones.

General information

Adhering to the cognitive approach to the description of the psyche, we represent a person as a kind of system that processes symbols in solving its problems, then we can imagine the most important feature of a person's personality - the sensory organization of the personality.

Sensory organization of personality

The sensory organization of the personality is the level of development of individual systems of sensitivity and the possibility of their association. The sensory systems of a person are his sense organs, as if receivers of his sensations, in which sensation is transformed into perception.

Every receiver has a certain sensitivity. If we turn to the animal world, we will see that the predominant level of sensitivity of any species is a generic trait. For example, bats have developed sensitivity to the perception of short ultrasonic pulses, dogs have olfactory sensitivity.

The main feature of the sensory organization of a person is that it develops as a result of his entire life path. The sensitivity of a person is given to him at birth, but its development depends on the circumstances, desire and efforts of the person himself.

What do we know about the world and about ourselves? Where do we get this knowledge from? How? The answers to these questions come from the depths of centuries from the cradle of all living things.

Feel

Sensation is a manifestation of the general biological property of living matter - sensitivity. Through sensation there is a psychic connection with the external and internal world. Thanks to sensations, information about all the phenomena of the external world is delivered to the brain. In the same way, a loop closes through sensations to receive feedback about the current physical and, to some extent, mental state of the organism.

Through sensations, we learn about taste, smell, color, sound, movement, the state of our internal organs, etc. From these sensations, holistic perceptions of objects and the whole world are formed.

It is obvious that the primary cognitive process takes place in human sensory systems, and already on its basis, cognitive processes that are more complex in their structure arise: perceptions, representations, memory, thinking.

No matter how simple the primary cognitive process may be, but it is precisely this that is the basis of mental activity, only through the “entrances” of sensory systems does the world around us penetrate into our consciousness.

Sensation Processing

After the information is received by the brain, the result of its processing is the development of a response or strategy aimed, for example, at improving physical tone, focusing more on current activities, or setting up for accelerated inclusion in mental activity.

Generally speaking, the response or strategy worked out at any given time is the best choice of the options available to the person at the time of the decision. However, it is clear that the number of options available and the quality of choice vary from person to person and depend on, for example:

mental properties of personality,

strategies for interacting with others

some of the physical condition,

experience, the availability of the necessary information in memory and the possibility of retrieving it.

the degree of development and organization of higher nervous processes, etc.

For example, the baby went out naked in the cold, his skin feels cold, perhaps chills appear, he becomes uncomfortable, a signal about this enters the brain and a deafening roar is heard. The reaction to cold (stimulus) in an adult may be different, he will either rush to get dressed, or jump into a warm room, or try to warm himself in another way, for example, by running or jumping.

Improving the higher mental functions of the brain

Over time, children improve their reactions, multiplying the effectiveness of the result achieved. But after growing up, the opportunities for improvement do not disappear, despite the fact that the adult's susceptibility to them decreases. It is in this that "Effekton" sees part of its mission: increasing the efficiency of intellectual activity by training the higher mental functions of the brain.

Effekton's software products make it possible to measure various indicators of the human sensorimotor system (in particular, the Jaguar package contains tests of the time of a simple audio and visual-motor reaction, a complex visual-motor reaction, and the accuracy of perception of time intervals). Other packages of the "Effekton" complex evaluate the properties of cognitive processes of higher levels.

Therefore, it is necessary to develop the perception of the child, and the use of the package "Jaguar" can help you with this.

Physiology of sensations

Analyzers

The physiological mechanism of sensations is the activity of the nervous apparatus - analyzers, consisting of 3 parts:

receptor - the perceiving part of the analyzer (carries out the conversion of external energy into a nervous process)

central part of the analyzer - afferent or sensory nerves

cortical sections of the analyzer, in which the processing of nerve impulses takes place.

Certain receptors correspond to their sections of cortical cells.

The specialization of each sense organ is based not only on the structural features of the receptor analyzers, but also on the specialization of the neurons that make up the central nervous apparatus, which receive signals perceived by the peripheral senses. The analyzer is not a passive receiver of energy; it is reflexively rebuilt under the influence of stimuli.

The movement of stimulus from the outer to the inner world

According to the cognitive approach, the movement of a stimulus during its transition from the external world to the internal one occurs as follows:

the stimulus causes certain changes in energy in the receptor,

energy is converted into nerve impulses

information about nerve impulses is transmitted to the corresponding structures of the cerebral cortex.

Sensations depend not only on the capabilities of the brain and sensory systems of a person, but also on the characteristics of the person himself, his development and condition. With illness or fatigue, a person changes sensitivity to certain influences.

There are also cases of pathologies when a person is deprived, for example, of hearing or sight. If this trouble is congenital, then there is a violation of the flow of information, which can lead to mental retardation. If these children were taught special techniques to compensate for their shortcomings, then some redistribution within the sensory systems is possible, thanks to which they will be able to develop normally.

Properties of sensations

Each type of sensation is characterized not only by specificity, but also has common properties with other types:

quality,

intensity,

duration,

spatial localization.

But not every irritation causes a sensation. The minimum value of the stimulus at which a sensation appears is the absolute threshold of sensation. The value of this threshold characterizes the absolute sensitivity, which is numerically equal to the value inversely proportional to the absolute threshold of sensations. And sensitivity to a change in the stimulus is called relative or difference sensitivity. The minimum difference between two stimuli, which causes a slightly noticeable difference in sensations, is called the difference threshold.

Based on this, we can conclude that it is possible to measure sensations. And once again you come to admiration from amazing delicately working devices - human sense organs or human sensory systems.

Effekton's software products make it possible to measure various indicators of the human sensory system (for example, the Jaguar package contains tests of the speeds of a simple audio and visual-motor reaction, a complex visual-motor reaction, the accuracy of time perception, the accuracy of space perception, and many others). Other packages of the "Effekton" complex also evaluate the properties of cognitive processes of higher levels.

Classification of sensations

Five basic types of sensations: sight, hearing, touch, smell and taste - were already known to the ancient Greeks. At present, ideas about the types of human sensations have been expanded, about two dozen different analyzer systems can be distinguished, reflecting the impact of the external and internal environment on receptors.

Sensations are classified according to several principles. The main and most significant group of sensations brings information from the outside world to a person and connects him with the external environment. These are exteroceptive - contact and distant sensations, they arise in the presence or absence of direct contact of the receptor with the stimulus. Sight, hearing, smell are distant sensations. These types of sensations provide orientation in the nearest environment. Taste, pain, tactile sensations - contact.

According to the location of receptors on the surface of the body, in muscles and tendons, or inside the body, they are distinguished, respectively:

exteroception - visual, auditory, tactile and others;

proprioception - sensations from muscles, tendons;

interoception - feelings of hunger, thirst.

In the course of the evolution of all living things, sensitivity has undergone changes from the most ancient to the modern. So, distant sensations can be considered more modern than contact ones, but in the structure of the contact analyzers themselves, one can also reveal more ancient and completely new functions. So, for example, pain sensitivity is more ancient than tactile.

Such classification principles help to group all kinds of sensations into systems and see their interaction and connections.

Types of sensations

Vision, hearing

Let us consider various types of sensations, bearing in mind that vision and hearing are the most well studied.

The eye is an absolutely extraordinary device that "mother nature" could only invent for our vision, a sensory organ with a very complex anatomical structure. Light waves reflected from objects are refracted, pass through the lens of the eye, which provides focusing of light, and appear on the retina in the form of an image.

Clear, sharp vision of equidistant objects is provided by a change in the curvature of the lens, called accommodation. This is the most important regulator of the function of vision. Various disorders can affect accommodation, which affects visual acuity, the level of discrimination of small details.

The retina of the eye is the front edge of the brain, the part of the visual analyzer farthest from the brain, which first perceives light, processes and converts light energy into irritation - a signal in which all information about what the eye sees is encoded. The study of this nerve formation helps to reveal the secrets of the visual mechanism created by nature. Yes, of course, "mother nature" did a great job creating such a perfect instrument of our vision.

The eye itself is a distant receptor, because it makes it possible to recognize objects remote from the sense organs and phenomena occurring around us. Our vision helps to determine the distance to objects and their volume. This is possible due to the pairing of the visual analyzer; on the retina, when moving away or approaching an object, the image size changes, and movement, i.e. convergence and dilution of the axes of the eyes.

The optic nerve fibers make up the retina of the eye, which consists of several tens of thousands of endings that are excited under the influence of a light wave. The endings of the optic nerve are different in form and function.

Receptors located in the center of the retina, similar in shape to cones, reflect color and are the apparatus of daytime vision. Rod-shaped nerve endings reflect light. Located around the cones, closer to the edge of the retina, they are the twilight vision apparatus. Cone and rod vision are independent of each other, so if one is impaired, the other remains unchanged.

Two groups of visual sensations can be distinguished:

achromatic, reflecting the transition from white to black, with all shades gray color And

chromatic, reflecting the color gamut with a large number of shades and tones of color.

Without the reflection of color, the world of man would become much poorer, in color sensations expressed and emotional background, for example, often talk about warm and cold color tones. The emotional impact of color is widely used in painting, and in any kind of art craft.

With the help of a visual analyzer, you can distinguish the brightness of the color and highlight the object from the general background. Black on white or white on black is especially visible. Thanks to the law of contrast, it becomes possible to distinguish all planar black and white images. If the object is far away and at the same time poorly lit, then for its unmistakable definition, the contrast should be high enough.

Perhaps, in the life of any person, visual sensations play the greatest role, without them human activity is very limited, and some types of activity are generally impossible, because. the main source of information is vision. The eyes, during long work, for example, on a computer, get tired, they need rest, the exercises of the "Comfort" package will come to their aid.

Hearing

Auditory sensations are also distant sensations. The sensory endings of the auditory nerve are located in the inner ear, the cochlea with the auditory membrane and sensory hairs. The auricle, the so-called outer ear, collects sound vibrations, and the mechanism of the middle ear transmits them to the cochlea. The sensory endings of the cochlea are excited as a result of resonance, i.e. the endings of the auditory nerve, different in length and thickness, set in motion at a certain number of oscillations per second, and the received signals are transmitted to the brain. These fluctuations occur in elastic bodies and transmitted by air. We know from physics that sound has a wave nature and is characterized by frequency and amplitude.

The frequency of sound is determined by the number of wave periods per unit of time. So, for example, the auditory range of an adult is in the range of 15 - 20,000 Hz, decreasing with age. Sounds differ not only in frequency, but also in timbre, giving uniqueness and peculiar coloring to the voice and sound of various musical instruments. The loudness of a sound depends on its amplitude and is measured in decibels (logarithmic scale). Normal conversation occurs at 50 - 60 dB, and rock music up to 130 dB, i.e. reaches the pain threshold.

There are three types of auditory sensations: speech, music and noise. In these types of sensations, the sound analyzer distinguishes four qualities of sound:

force (loud - weak),

height (high - low),

sound duration and tempo-rhythmic pattern of perceived sounds.

Phonemic hearing is called hearing, using which you can distinguish the sounds of speech. It is formed during life and depends on the speech environment. Good knowledge of a foreign language involves the development new system phonemic hearing. The ability to learn foreign languages ​​is determined by phonemic hearing, which also affects the literacy of written speech.

The musical ear of a person is brought up and formed, as well as speech. The ability to enjoy music is a centuries-old result of the development of the musical culture of mankind.

Noises and rustles are less significant for a person, unless they interfere with his life. Noises can cause a pleasant emotional mood, for example, the sound of rain, the roar of the surf, and, one of my acquaintances, the administrator computer network said that he could not sleep when he did not hear the noise of the fans running from three or four computers. Noises can also serve as a danger signal - the hiss of gas, the clatter of feet behind your back, the howl of a siren.

Smell, touch, vibratory and proprioceptive sensations

A person has the most developed vision and hearing, respectively, they are the most studied, although there are other senses that are also important for a person in his daily life.

vibration sensations

Vibrational sensitivity can be associated with auditory sensations, because. they have a common nature of reflected physical phenomena. Vibration sensations reflect vibrations of an elastic medium. This kind of sensitivity can be called "contact hearing". No specific vibration receptors have been found in humans. It is believed that the vibrational sense is one of the most ancient types of sensitivity, and all tissues of the body can reflect the vibrations of the external and internal environment.

In human life, vibrational sensitivity is subordinated to auditory and visual. The cognitive value of vibration sensitivity increases in those activities where vibrations become a signal of malfunctions in the operation of the machine. In the life of the deaf and deaf-blind, vibrational sensitivity compensates for hearing loss. organism healthy person short vibrations tone up, long and intense vibrations tire and cause painful phenomena.

Smell

The olfactory sensation receptor is the end of the olfactory nerve in the nasal cavity, it belongs to the distant ones. Microscopic particles of substances that enter the nasal cavity with air, being irritants, cause olfactory sensations.

In animals, the sense of smell is the main distant receptor, guided by smell, the animal finds food or avoids danger. The sexual behavior of animals depends on the production of special substances - pheromones. There is a theory that in humans, pheromones play an important role in matters of sex.

Man in modern world there is no need to follow the olfactory sensations, orienting in the environment. The function of smell in humans is suppressed by sight and hearing. The absence in the language of special words for designating olfactory sensations indicates their insufficient development and instability. Usually they say: "the smell of the sea", "the smell of roses", "the smell of the stables".

Olfactory sensitivity is closely related to taste, helps to recognize the quality of food. The sense of smell warns of a dangerous air environment for the body, allows you to distinguish in some cases chemical composition substances.

Taste sensations are contact, arising from the contact of the sense organ (tongue) with the object itself. The sense of taste detects molecules dissolved in saliva.

There are four main qualities of taste stimuli: sour, sweet, bitter, salty. From the combinations of these four sensations, to which tongue movements are added, a complex of taste sensations arises.

Initially, the sensory process occurs in the taste buds, and each of the papillae has from 50 to 150 receptor cells, which are quickly worn out from contact with food and then renewed. Sensory signals then travel along nerves to the hindbrain, thalamus, and gustatory cortex, which processes taste sensations.

Taste sensations, like olfactory ones, increase a person's appetite. Analyzing the quality of food, taste sensations also perform protective function and essential for survival. When fasting, taste sensitivity increases, when saturated or satiety - decreases.

In the skin there are several independent analyzer systems:

tactile (sensation of touch),

temperature,

All types of skin sensitivity are referred to as contact sensitivity. The largest accumulation of tactile cells is in the palm, on the fingertips and on the lips. Skin receptors transmit information to spinal cord, making contact with motor neurons, which makes possible reflex actions such as, for example, pulling the hand away from the fire. The sense of touch is the tactile sensations of the hand along with the musculo-articular sensitivity.

Temperature sensitivity regulates heat transfer between the body and the environment. The distribution of heat and cold receptors over the skin is uneven. The back is most sensitive to cold, the least - the chest.

Strong pressure on the surface of the body causes pain. The receptor endings of pain sensitivity are located under the skin, deeper than the tactile receptors. Where there are more tactile receptors, there are fewer pain receptors. Tactile sensitivity gives knowledge about the qualities of the object, and pain sensitivity gives a signal about the harm caused by the stimulus.

proprioceptive sensitivity

Kinesthesia

Kinesthetic sensations are sensations of movement and position. separate parts body. Kinesthetic sensation receptors are located in muscles and tendons. Irritation in these receptors occurs under the influence of muscle stretching and contraction.

A large number of motor receptors are located in the fingers, tongue and lips, since these organs need to carry out precise and subtle working and speech movements. The activity of the motor analyzer allows a person to coordinate and control his movements. The exercises for the hands of the "Comfort" package improve blood circulation, reduce tension and fatigue, promoting better coordination of movements and increasing mental performance.

It is clear that the development of kinesthetic sensations is one of the most important tasks of education.

Speech kinesthesias are formed in the infantile and preschool periods of human development. Education foreign language requires the development of such speech kinesthesias that are not typical for the native language.

vestibular sense

Static, or gravitational, sensitivity reflects the position of our body in space. Its receptors are located in the vestibular apparatus of the inner ear: semicircular canals and vestibular sacs convert signals about relative motion and gravity and transmit them to the cerebellum and the cortex of the temporal region. Sudden and frequent changes in the position of the body relative to the plane of the earth, such as swinging on a swing or sea rolling, lead to dizziness - "seasickness".

Do humans have enough sense organs?

Sensations provide the body with adequate orientation in the environment. Could a person get to know the world around him more deeply if he had more sense organs?

Philosophers-idealists made a conclusion about the limited cognitive capabilities of a person, linking this with the limitedness of the sense organs and the variety of phenomena in the surrounding world.

Materialists believed that the existing sense organs are sufficient for a complete knowledge of the world. Cognition goes deeper, the cognitive power of a person lies in the fact that the activity of his sense organs is added to the activity of thinking, which pushes the limits of cognitive possibilities.

To ensure the normal functioning of an organism*, the constancy of its internal environment, connection with the constantly changing external environment and adaptation to it are necessary. The organism receives information about the state of the external and internal environments with the help of those who analyze (distinguish) this information, provide the formation of sensations and ideas, as well as specific forms of adaptive.

The concept of sensory systems was formulated by IP Pavlov in the doctrine of analyzers in 1909 during the study of them. Analyzer- a set of central and peripheral formations that perceive and analyze changes in the external and internal environments of the body. The concept of "sensory system", which appeared later, replaced the concept of "analyzer", including the mechanisms of regulation of its various departments with the help of direct and feedback. Along with this, there is still the concept of "sense organ" as a peripheral entity that perceives and partially analyzes environmental factors. The main part is equipped with auxiliary structures that provide optimal perception.

With the direct impact of various environmental factors with the participation in the body, there are Feel, which are reflections of the properties of objects of the objective world. The peculiarity of sensations is their modality, those. the totality of sensations provided by any one sensory system. Within each modality, in accordance with the type (quality) of the sensory, different qualities can be distinguished, or valency. Modalities are, for example, sight, hearing, taste. Qualitative types of modality (valency) for vision are various colors, for taste - the sensation of sour, sweet, salty, bitter.

The activity of sensory systems is usually associated with the emergence of five senses - sight, hearing, taste, smell and touch, through which the body is connected with the external environment. However, in reality, there are much more of them.

The classification of sensory systems can be based on various features: the nature of the acting stimulus, the nature of the sensations that arise, the level of sensitivity of receptors, the rate of adaptation, and much more.

The most significant is the classification of sensory systems, which is based on their purpose (role). In this regard, there are several types of sensory systems.

External sensor systems perceive and analyze changes in the external environment. This should include visual, auditory, olfactory, gustatory, tactile and temperature sensory systems, which are perceived subjectively as sensations.

Internal (visceral) sensory systems perceive and analyze changes in the internal environment of the body, indicators of homeostasis. Fluctuations in the indicators of the internal environment within the physiological norm in a healthy person are usually not perceived subjectively in the form of sensations. So, we cannot subjectively determine the value of blood pressure, especially if it is normal, the state of the sphincters, etc. However, information coming from the internal environment plays important role in the regulation of the functions of internal organs, ensuring the adaptation of the body to different conditions his life activity. The significance of these sensory systems is studied in the course of physiology (adaptive regulation of the activity of internal organs). But at the same time, a change in some constants of the internal environment of the body can be perceived subjectively in the form of sensations (thirst, hunger, sexual desire), which are formed on the basis of biological ones. To meet these needs, behavioral responses are included. For example, when a feeling of thirst arises due to the excitation of osmo- or volumic receptors, it is formed, aimed at searching for and receiving water.

Sensory systems of body position perceive and analyze changes in the position of the body in space and body parts relative to each other. These include the vestibular and motor (kinesthetic) sensory systems. As we evaluate the position of our body or its parts relative to each other, this impulse reaches our consciousness. This is evidenced, in particular, by the experience of D. Maklosky, which the scientist put on himself. Primary afferent fibers from muscle receptors were irritated by threshold electrical ones. An increase in the frequency of impulses of these nerve fibers evoked subjective sensations in the subject of a change in the position of the corresponding limb, although its position did not actually change.

nociceptive sensory system should be singled out separately in connection with its special significance for the body - it carries information about damaging actions. Pain can occur with irritation of both extero- and interoreceptors. .

Interaction of sensory systems carried out at the spinal, reticular, thalamic and cortical levels. The integration of signals in . Signals are integrated in the cerebral cortex higher order. As a result of multiple connections with other sensory and non-specific systems, many cortical systems acquire the ability to respond to complex combinations of signals of different modalities. In particular, this is characteristic nerve cells association areas of the cerebral cortex, which have high plasticity, which ensures the restructuring of their properties in the process of continuous learning to recognize new stimuli. Intersensory (cross-modal) interaction at the cortical level creates the conditions for the formation of a "scheme of the world" (or "map of the world") and continuous linking, coordination with it of the body's own "scheme" of a given organism.

With the help of sensory systems, the body learns the properties of objects and phenomena of the environment, useful and negative sides their effects on the body. Therefore, violations of the function of external sensory systems, especially visual and auditory, make it extremely difficult to know the outside world (the surrounding world is very poor for the blind or deaf). However, only analytical processes in the CNS cannot create a real idea of ​​the environment. The ability of sensory systems to interact with each other provides a figurative and holistic view of the objects of the external world. For example, we evaluate the quality of a lemon wedge using visual, olfactory, tactile, and gustatory sensory systems. At the same time, an idea is formed both about individual qualities - color, consistency, taste, and about the properties of the object as a whole, i.e. a certain integral image of the perceived object is created. The interaction of sensory systems in assessing phenomena and objects also underlies the compensation of impaired functions in the event of loss of one of the sensory systems. For example, in the blind, the sensitivity of the auditory sensory system increases. Such people can determine the location of large objects and bypass them if there is no extraneous noise due to reflection sound waves from the object in front. American researchers observed a blind man who accurately determined the location of a large cardboard plate. When the subject's ears were covered with wax, he was unable to determine the location of the cardboard.

Interactions of sensory systems can manifest themselves in the form of the influence of excitation of one system on the state of excitability of another according to the dominant principle. For example, listening to music can cause pain relief during dental procedures (audio analgesia). Noise impairs visual perception, bright light increases the perception of sound volume. The process of interaction of sensory systems can manifest itself at various levels. The reticular formation, the cerebral cortex, plays a particularly important role in this. Many cortical neurons have the ability to respond to complex combinations of signals of different modalities (multisensory convergence), which is very important for learning about the environment and evaluating new stimuli.