Our perception reflects the world not always correct. Sometimes it is prone to deceit. Deception of perception also includes complex mental disorders that involve perversion of the mechanisms of perception. Illusions and hallucinations involve the revival of stored images, which are supplemented by imagination.

Illusions

Disorders in which existing real objects are perceived as completely different objects are called.

Illusions must be distinguished from errors of perception healthy people, whose problems are caused by insufficient information about objects and objects. For example, at dusk, some objects are perceived as others. The reason for this is the insufficient visibility of the object, while the imagination independently draws the missing details. As a result, the brain receives an image of an object that differs from reality.

Illusions often accompany mental disorders, while having a fantastic character and arising even in cases where there are no obstacles to the teaching of information.

Kinds

1. Affectogenic illusions- a delusion of perception, which appears under the influence of extreme anxiety and fear. When delirium is manifested, people tend to endow the environment with special features that cause anxiety in it. For example, in the conversation of random people, the name of the patient may be heard.
2. paraidol illusions- fantastic images of a complex nature that arise violently when considering real things and objects. Pareidolia is a complex mental disorder that precedes the onset of hallucinations. Usually this phenomenon is observed in the initial period of clouding of consciousness (for example, with delirium tremens or fever).

From illusions it is necessary to distinguish the desire of healthy people to fantasize. A healthy psyche always distinguishes real objects from imaginary ones and is able to distinguish a stream of ideas in a timely manner.

Disorders of perception, in which objects and phenomena are found where in reality they are not, are called hallucinations.

A distinctive feature of hallucinations from illusions is that the first ones arise practically “from scratch”, and at x, real objects are distorted. Hallucinations indicate a deep mental disorder and cannot be observed in mentally healthy people in the normal state. As a rule, hallucinations occur in people with mental illness or in an altered state (for example, in a state of hypnosis).

Types of hallucinations

Various bases are used to classify hallucinations.

• There are hallucinations in the senses:

- visual;

- auditory;

- tactile;

- olfactory;

- taste;

- hallucinations of general feeling.

The last type of hallucinations, as it were, comes from within, that is, the patient feels himself somewhere or someone, or maybe he feels something inside himself. The combination of sensations is difficult to attribute to one specific feeling, for this reason hallucinations of this type are called the general type.

• In relation to the phases of sleep, hallucinations are:

- hypnagogic - occurring when falling asleep;

- hypnopompic - appearing upon awakening.

These hallucinations accompany mental disorders, but can also occur in healthy people with overwork.

• Functional (reflex) hallucinations can occur when exposed to a specific stimulus. An example of these hallucinations might be:

- extra noise in the shower;

- parallel speech when turning on the TV, etc.

If you remove the stimulus, then the hallucinations will disappear.

- elementary hallucinations are manifested in the form of short signals: knock, rustle, click, crackle, lightning, flash, dot, etc .;

- simple hallucinations are associated with one specific analyzer and are distinguished by a clear structure and objectivity. An example would be a voice delivering a clear speech;

- complex hallucinations combine the deceptions of several analyzers at once. At the same time, the whole situation human environment can be completely transformed into non-existent images. A person hears sounds and voices, sees non-existent objects, feels touches and wind. These are scene-like hallucinations.

Illusions and hallucinations are perceptual delusions. But they do not exist on their own, but accompany certain mental disorders. For this reason, it is necessary to prescribe the treatment of causes, not effects.

See the hole? It's just painted on the pavement. This is the illusion of depth.

Perceptual errors are called illusions (from the Latin word illusio- delusion, deceit). This is a misperception of an object that really exists. There is a group of typical visual illusions that occur in almost all people. So, for example, vertical lines appear longer than horizontal lines, even though they are the same length. Knowledge of these typical illusions, as well as, for example, the perception of colors, is used in design - clothes, rooms. For example, any woman knows that longitudinal stripes visually expand the figure, and black color makes the figure visually more slender. The dark color of the walls visually reduces the room, and the light color, on the contrary, expands it. Green tones soothe, and red tones excite, so red is suitable for cafes, and in hospitals, factory rooms, the background should be neutral, not annoying. Example visual illusion you see in the picture. Are the horizontal lines in the middle of the drawing straight or not?

They are straight, but we have the illusion that they are not straight.

Illusion of square shape distortion.

Hallucination(from the Latin word hallutinatio- vision) is the perception of objects that do not really exist. Hallucinations are symptoms of a wide variety of mental illnesses. It is impossible to convince a person with hallucinations that a hallucinatory image does not exist: “How can you not see, because here is a dog, red hair, here it is, here it is ...” For him it is so real, he “sees” her. Do not confuse illusions with hallucinations. So, if a person in the dark saw a hat and it seemed to him a cat, this is an illusion. If he saw a cat in an empty place, then this is a hallucination.

Test

1.Feeling is:

a) subjective image of the objective world

b) knowledge of the essential properties of objects and phenomena.

c) knowledge of individual properties of objects or phenomena

d) knowledge of integral objects and phenomena that affect our senses

2. Reception of environmental signals is carried out nervous system by using:

a) the brain

b) receptor

c) nerve pathways

d) analyzer

3. The exteroceptive sensations include:
a) thirst;

b) vibrations;

c) visual

d) organic

4. The property of sensations, which manifests itself in the fact that the stimulus acts on one analyzer, and the sensation appears in another analyzer:

a) synesthesia

b) sensitization

c) illusion

channeling

Doing channeling sessions with Higher Powers on different topics.

Illusions and hallucinations. Types and causes of hallucinations and illusions. Agnosia.

Illusions

Wrong distorted perception illusion

Illusions and hallucinations.

Illusions

Wrong distorted perception objects and phenomena is called illusion. Certain types of illusions occur in healthy people. However, in contrast to the sick, they do not disturb healthy people's generally correct identification of an object, since a healthy person has sufficient opportunities to verify the correctness of clarifying his first impression.

Many different illusions observed in almost all healthy people. The illusion of non-parallelism occurs when parallel lines are crossed by other lines. One of the types of illusion is also the transfer of the properties of the whole figure to its individual parts. A line segment that is part of a large figure seems to be longer than an equal line that is part of a small figure.

Illusions can also be a manifestation of mental disorders. Thus, in mental illness derealization syndrome which is based on a distorted perception of the objects of the surrounding world ("Everything is frozen, glazed", "The world has become like a scenery or a photograph").

These perceptual distortions can be quite definite in nature and relate to certain features of objects - shape, size, weight, etc. In these cases, one speaks of metamorphopsia. The latter include macropsia when objects appear enlarged, micropsia- Objects are perceived as reduced. At porropsy distance assessment is disturbed: the patient imagines that objects are further away than they are in reality.

Peculiar illusions in the form of a violation of the perception of one's own body("body schema disorders") are seen in depersonalization syndrome, characterized by a distortion of the perception of one's own personality ("Feeling of loss and split of I", "Alienation of I", etc.).

When the "body schema" is disturbed, patients experience peculiar sensations of an increase or decrease in the whole body and its individual parts: arms, legs, head ("Hands are very large, thick", "Head has increased dramatically"). It is characteristic that these distortions in the perception of body parts are often critically evaluated by patients, they understand their painful, false nature. Disorders of the "body scheme" also include a violation of the idea of ​​the ratio of body parts, the position of the body ("Ears are now placed side by side - on the back of the head", "The body is turned 180 °", etc.).

Some forms of anosognosia are also disorders of the perception of one's body., in which the patient does not notice that his limbs are paralyzed, and claims that he can get out of bed at any moment and go. Anosognosia of this type is usually observed with paralysis of the left limbs caused by damage to the right fronto-parietal region of the brain.

The nature of illusory perception is also polyesthesia- a feeling of several angles in the circle of a point on the surface of the skin, into which an injection was made with the tip of a needle. With synesthesia, a prick is felt in symmetrical parts of the body. So, when an injection is made in the region of the dorsum of the right hand, the patient simultaneously feels an injection in the corresponding point of the left hand.

hallucinations

hallucinations differ from illusion in that false perception occurs in the absence of the subject. Hallucinations occasionally occur in healthy people. So, during long passages through the desert, when people are thirsty, it begins to seem to them that there is an oasis, a village, water ahead, while in fact they are not.

In most cases, hallucinations are observed in mental patients. Most common auditory hallucinations. Patients hear the whistle of the wind, the noise of motors, the creak of brakes, although in reality these sounds do not exist in their environment. Often auditory hallucinations are verbal in nature. It seems to the patients that they are called out, they hear snippets of a non-existent conversation. Influenced verbal hallucinations of an imperative, commanding nature, such patients can commit wrong actions, including attempts to commit suicide.

At visual hallucinations various pictures appear before the eyes of patients: they see terrible, unusual animals, frightening human heads, etc. There are also olfactory, gustatory hallucinations. In some cases, especially with visual hallucinations, there is a combination of them with hallucinations in the sphere of other organs, for example, with auditory and verbal hallucinations.

Hallucinations may be neutral in nature and devoid of emotional coloring. Patients perceive such hallucinations calmly, often even indifferently. However, in some cases, hallucinations have a sharp emotional coloring, most often negative. Frightening hallucinations also belong to the deceptions of the senses of this kind.

In some observations hallucinations can be a source of positive emotions for the sick. So, M.S. Lebedinsky described a mother who lost her son with a severe pathological reaction to his death. This patient often "saw" the deceased in hallucinations and rejoiced at these "meetings".

The false nature of perception usually goes unnoticed by patients suffering from hallucinations. They are convinced of the truth of their perception, it seems to them that incorrectly perceived objects and phenomena really exist in the environment.

Pseudo-hallucinations

In contrast to the so-called true hallucinations, pseudo hallucinations patients are aware of their false character. The hallucinatory image is not localized in external environment but directly in the minds of the patients themselves. Pseudo-hallucinatory experiences can include, in particular, the sound of one's own thoughts, often experienced by patients with schizophrenia.

Causes of hallucinations and illusions

The mechanism of illusions and hallucinations is still poorly understood. The reasons for the violation of the active, selective nature of perceptions revealed in illusions and hallucinations are still not clear enough.

Some illusions observed in healthy people can be explained by the so-called attitude, i.e. distortion of perception arising under the influence of immediately preceding perceptions. This phenomenon has been widely studied by psychologist D.N. Uznadze and his school. The following experiment can serve as an example of the formation of a set. The subject is placed in both hands 15-20 times in a row a large and small ball of the same weight. Then two balls of the same volume are presented. Some subjects usually evaluate one of the balls as smaller, with the hand in which the small ball lay. Other subjects find the opposite (contrasting) setting and evaluate with the same hand a ball of equal volume as large.

It is possible that the pathology of the installation mechanism explains some of the illusions of the size of objects observed in patients. With regard to the pathogenesis of the origin of hallucinations, the most likely assumption is that they are associated with pathological, increased excitability of certain areas in the human brain. This point of view is supported, in particular, by the experiments of the famous Canadian neurosurgeon W. Penfield, who caused visual and auditory hallucinations by electrical stimulation of sections of the temporal and occipital lobes of the cerebral cortex during operations for epilepsy.

Agnosia.

Agnosia called a violation of visual, auditory and kinesthetic perceptions in local lesions of the cerebral cortex caused by vascular diseases, injuries, tumors and other pathological processes. At object agnosia the violation of the generalized perception of objects comes to the fore: patients cannot recognize the images of a table, chair, kettle, key and other objects, but in the case when they recognize an object, they can also indicate its individualized reference. So, having learned that this is a person’s face, patients can say whether this person is familiar to them, remember his last name. Having recognized the chairs in the doctor's office, patients with object agnosia can indicate the same type or other chairs in shape and decoration located in the wards, corridors of the clinic.

Some patients have visual disturbances, in which the generalized perception of objects remains relatively intact and the disorder of individualized perception comes to the fore. Such patients experience difficulty in recognizing specific single objects that they have seen before. These violations are especially pronounced when it is necessary to recognize familiar faces. Patients do not know whether they have seen this face before or not, a female or male face in front of them, they poorly distinguish facial expressions, do not catch expressions of joy, fun, laughter, sadness, crying. This form of visual agnosia is called face agnosia, or agnosia of individualized features.

One of the forms of violations of visual gnosis is called optic-spatial agnosia. With this form of visual agnosia, the patient's perception of the spatial arrangement of individual objects is disturbed, patients cannot correctly perceive spatial relationships. Once in the clinic, they cannot learn to find their way to the doctor's office, to the dining room, to the toilet. They recognize their ward only by indirect signs - by the number above the entrance to the ward or by the characteristic color of the ward door. These patients also experience great difficulty when trying to find their bed in the ward. They forget the location of the streets of the city in which they lived for a long time, they cannot tell about the plan of their apartment.

Causes of agnosia

Usually, visual agnosias are observed when the occipital or partially lower-posterior sections of the parietal lobes of the brain are affected.

With damage to the lower anterior parts of the parietal lobes of the brain, disorders of higher forms of tactile perception, called astereognosis, are noted. Feeling with closed eyes any object (key, coin, pencil, pen, comb, etc.) "patients cannot determine the shape and size of this object, recognize it. At the same time, with visual perception, patients quickly recognize this object and unmistakable.

There are also observations from auditory agnosia observed in lesions of the temporal regions of the brain. In patients with this form of agnosia, auditory perception is impaired. They cannot recognize the characteristic noise of the wind, an airplane, a car, the sounds made by different animals, the rustle of paper, etc.

At the heart of agnosia lie, apparently, violations of the processes of isolating a signal from noise, isolating the characteristic features of objects and comparing these features with those samples, standards that are stored in the memory of patients.

The process of perception demonstrates the subjective mental reflection of objects and phenomena of objective reality. Common to these processes is the fact that they begin to function only with the direct impact of irritation on the sensory organs. Perception reflects an object or phenomenon as a whole, in the aggregate of properties. It is the process of meaningful synthesis of the image of an object or phenomenon with their active reflection that is the main one in perception.

ILLUSIONS- this is a distorted perception of an object that really exists in the external environment.

Illusions are deviations in the perception of a particular perceived object in terms of shape, color, size, consistency, constancy, remoteness from the perceived. Visual illusions manifest themselves as a distortion of the visual image (the perception of a coat hanging in the closet real person based on the similarity of the contours). Among the visual ones, they are especially distinguished pareidolic illusions in which the formation and perception of bizarre visual images based on the merging of the elementary perceived features of the object (cracks or a pattern on the wall is perceived as an image of an animal) takes place. Auditory illusions are characterized by impaired perception of real noises, sounds that can be perceived as speech or other sounds (a sharp noise outside the door can be perceived as a doorbell in case of affective tension of a person, a scream in the street - as a response by name). Taste illusions are manifested by a modification of the usual taste for the object (the appearance of a “taste”); olfactory illusions - smell.

HALLUCINATIONS- perceptions that arise without the presence of a real object, accompanied by the conviction that this object is in given time and in this place really exists.

Unlike illusions, hallucinations occur regardless of the existence of the object and in the overwhelming majority of cases are accompanied by the patient's belief in the reality of hallucinatory images. Visual and auditory hallucinations are divided into simple (photopsia - the perception of bright flashes of light, circles, stars; acoasma - the perception of sounds, noise, crackling, whistling, crying) and complex (verbal - the perception of articulate phrasal speech). Attention should be paid to one of the main criteria for differentiating true and false hallucinations - the reality of the projection of a hallucinatory image. Its essence lies in the fact that with true hallucinations, the patient indicates the location of the image, as a rule, outside and at a real distance for perception (for example, the image of a person seen by him on the street, and not on the moon; heard behind the wall, and not from a distance thousands of kilometers or out of my head).

False and true hallucinations: criteria for differences

Criteria	True	False
objective reality	The object is indistinguishable from the real one (the patient perceives it as a real object - there is a “devil”, “chair”, “cockroaches” in front of him	“Madeness” of the object (embedded thoughts (Kill him!), someone acts with hypnosis, rays), being out of sight (I see Red Square while in N-sk, I see a witch behind me)
Social Confidence	Everyone distinguishes (because the devil is in front of me, then everyone sees him too)	Only the patient (only I hear these thoughts, the hypnotic effect is directed at me)
Relevance of behavior	According to the content (if he sees the devil, he fights or runs away, on his face - fear, shouts to everyone to save themselves too)	“Watches” (listens to himself, sometimes hides)
Orientation	On the physical "I" (the crocodile will attack and eat)	On the mental "I" (they will take out my brain and put their own, cybernetic, put thoughts, other people's feelings)
More common	With organic disorders, delirium, twilight disorder of consciousness	With schizophrenia

The presence of hallucinations always indicates the severity of psychopathological symptoms. Hallucinations are a sign of psychotic disorders (delirium, Sch), but sometimes they can be in healthy people (sensory deprivation)

EIDETISM- a trace of the excitation that has just ended in any analyzer in the form of a clear and bright image.