Causes, diagnosis and social adaptation of the patient in the treatment of agnosia. Agnosia - the main causes, types and methods of correction of the disorder Pain agnosia

Gnostic auditory disorders (auditory agnosia) observed with right-sided lesions of fields 41, 42 and 22 of the cerebral cortex (secondary projection zones of the auditory cortex). Damage to similar areas of the left hemisphere is accompanied by speech disorders, which is commonly called aphasia.

Auditory agnosia divided into subdominant and dominant .

Subdominant auditory agnosia manifests itself in the inability to master the meaning of non-speech noises, namely: a) natural, i.e., emitted by natural objects; b) objective, i.e., produced by sounding objects.

Non-speech auditory agnosia occurs when the right temporal lobe is affected. In this case, children do not distinguish sounds such as creaks, knocks, pops, rustles, beeps, the noise of wind, rain, etc. A certain category of children, and more often adult patients, have defects in impressive musical hearing (amusia). It manifests itself as an inability to remember or recognize a melody. Sometimes patients experience increased sensitivity to noise (hyperacusis), as well as cases of changes in the intonation and melodic aspects of speech, voice, and elements of dysarthria. When the right hemisphere is damaged, non-verbal auditory functions such as distinguishing the duration of sounds, perception of sound timbre, the ability to localize sounds in space, as well as the ability to recognize the voices of familiar people, especially on the telephone or radio, are impaired.

Dominant auditory agnosia occurs with lesions located in the left hemisphere of the brain. It is speech-related and manifests itself in difficulties in understanding speech. At the same time, partial understanding of speech is sometimes possible, which is achieved by relying on the length of the phrase, intonation, and the situation of communication, i.e., on what, according to modern ideas, is within the “competence” of the right hemisphere of the brain. With lesions located in the right temple, the patient, trying to understand an aurally perceived utterance, primarily relies on the sound, phonemic composition of the word and, as a result of the phonological analysis, understands the objective meanings of the words. Difficulties in decoding the prosodic characteristics of an utterance, characteristic of pathology of the right hemisphere of the brain, limit the scope of understanding the text perceived by ear, but are not completely eliminated. Only bilateral lesions lead to gross speech auditory agnosia.

Speech auditory agnosia is the most complex manifestation of auditory agnosia. Speech perception is carried out due to the joint activity of the two temporal zones of the brain (right and left). Unilateral lesions of the temporal lobe, as a rule, do not cause complete auditory agnosia.

– the patient hears sounds: creaking doors, footsteps, pouring water, etc. (i.e., hearing is preserved), but does not recognize them;

– observed in mild cases auditory memory impairment. The patient does not remember sound complexes of varying complexity. For example, cannot reproduce successive sounds of different pitches;

–amusia– impairment of the ability to recognize (sensory amusia) and reproduce (motor amusia) a familiar or just heard melody, to distinguish one melody from another. Music loses its meaning and can cause unpleasant painful experiences (“unpleasant to hear”). Amusia most often occurs with damage to the right hemisphere. In sensory amusia, the lesion is located in the temporal region, and in motor amusia, in the posterior parts of the middle frontal gyrus;

- at violation of intonation aspects of speech the patient does not distinguish speech intonations. His own speech lacks intonation variety. Sometimes the patient does not distinguish between male and female voices and loses the ability to distinguish between interrogative, affirmative and exclamatory statements. Impaired intonation hearing manifests itself as a difficulty in the ability to identify the emotional state of the speaker (joy, anger, sadness).

It is generally accepted that there is a violation of the perception of rhythms, their retention in memory and reproduction according to the pattern ( arrhythmia) can occur in both right- and left-sided lesions. At the same time, patients experience difficulty in reproducing rhythmic structures that they present “by ear.” When the left temporal region is damaged, the acoustic analysis and synthesis of the internal structure of the rhythm are primarily affected, therefore, the more complex (accented, double) the series is subject to memorization and reproduction, the greater the likelihood of errors in its implementation. In right-hemisphere lesions, the perception of the structural design of the rhythmic cycle as a whole is disrupted to a greater extent: structurally designed rhythm packs are better reproduced compared to simple ones.

Diagnosis of gnostic hearing disorders[H6] .

1. Playing sound rhythms. The patient is asked, following the experimenter, to reproduce a series of blows on the table, separated by long and short pauses. The series gradually lengthen and become more complex in structure.

Sample rhythms: ½½ ½ …½ ½½ …

2. Localization of sound in space. The subject is asked to determine from which side the sound comes.

3. Recognition of familiar sounds. The subject is asked after listening to identify familiar sounds (for example, the rustling of paper).

What is agnosia?

Agnosia - this is a violation of the recognition of phenomena and objects while maintaining consciousness and elementary sensitivity. The term " " comes from the prefix "a", meaning the absence of a characteristic, and the Greek word "gnosis", meaning "cognition".

Causes

Agnosia occurs with extensive lesions of certain parts of the cerebral cortex. Agnosia is more often associated with pathology predominantly in right-handers of the right hemisphere, and in left-handers - of the left hemisphere. That is, with pathology of the base hemisphere for imaginative, artistic thinking and perception. Causes of agnosia: Alzheimer's disease, cerebrovascular accidents, subacute sclerosing panencephalitis, posthypoxic and/or toxic encephalopathy, compact processes.

Agnosia in adults and children

Agnosia more common in adults (men and women). Agnosia in children (boys and girls) it occurs at an older age (from 10 to 17 years) due to the fact that pathology and more pronounced differentiation of the functional zones of the cerebral cortex are better identified in them.

Agnosia, types, classification

Basic types of agnosia: visual agnosia (optical agnosia), auditory agnosia, tactile agnosia (astereognosis), olfactory agnosia, taste agnosia, pain agnosia, anosognosia, autotopognosia.

Visual agnosia, optical agnosia

Visual agnosia , optical agnosia - this is a type of agnosia in which there is a failure to recognize familiar objects or some of their properties and qualities, in the absence of blindness. Visual agnosia, or optical agnosia, occurs due to pathological processes in the occipital-parietal region, the occipital region. Occurs in such types of pathology as Alzheimer's disease and cerebrovascular accidents. Visual agnosia, optical agnosia has several types. Basic symptoms of visual agnosia: decreased vision, weakened vision, impaired vision. However, when examining a person, there is no decrease in vision. The patient cannot explain the purpose of objects and name them correctly.

Object-visual agnosia, visual-object agnosia

Object-visual agnosia - this is an apparent decrease in vision, combined with the inability to name the object that is shown to the patient (toothbrush, spoon, shoes, panties, cup, plate, glass, book).

Spatial visual agnosia, spatial agnosia

is a violation of the ability to navigate in space or evaluate spatial relationships. Spatial-visual agnosia characterized by a lack of recognition of complex spatial images, loss of spatial concepts, and impaired orientation in the area. Spatial visual agnosia is observed with damage to the lower parts of the parietal lobes of the brain. Often spatial-visual agnosia is combined with aprakto-agnostic syndrome.

Metamorphopsia

Metamorphopsia is a type of agnosia in which the perception of objects is observed in a distorted form. Macropsia is a type of metamorphopsia in which objects appear enlarged. Micropsia is a type of metamorphopsia in which objects appear smaller.

Finger agnosia

Finger agnosia - this is a violation of choice, recognition, differentiated display of fingers (toes). Impaired finger recognition occurs both in oneself and in other people. Finger agnosia belongs to a group of pathologies such as autotopognosia.

Facial agnosia, prosopagnosia

Agnosia on faces , or prosopagnosia - this is a violation of recognition of perfectly familiar people's faces. If a person’s face is not recognized, the patient says that he allegedly cannot see well, so he cannot recognize it. In fact, the patient's vision is good. Agnosia for faces, according to Sarklinik, is observed with damage to the temporal and/or occipital parts of the brain, more often than not the non-dominant hemisphere. Alzheimer's disease is a common cause of facial agnosia (prosopagnosia).

Simultaneous agnosia

Simultaneous agnosia - this is the impossibility of complete and holistic perception of a complex of sensory images of various modalities and a violation of recognition of an integral general image from part of the image. At the same time, recognition of complete and individual images is preserved. With simultaneous agnosia, quite complex disturbances in the synthetic processes of sensory image formation are observed. According to Sarklinik, simultaneous agnosia occurs when the occipital, parietal, and temporal regions are affected in the area of their conjugation. Some patients call it "simultaneous agnosia."

Also found are associative agnosia and apperceptive agnosia.

Auditory agnosia

Auditory agnosia - this is the inability to recognize familiar sounds, while hearing is intact. It is observed with damage to the frontal and temporal regions, secondary cortical zones of the hearing analyzer. Verbal agnosia is the inability to understand the meaning of familiar words while hearing is intact. With verbal agnosia, the secondary zones of the hearing analyzer in the dominant hemisphere are affected. Often noted with.

Amusia

Amusia is the inability to recognize musical melodies. In amusia, the non-dominant hemisphere is affected. Also, with disorders in the subdominant hemisphere, it becomes difficult to assess the intonation component of speech.

Tactile agnosia, astereognosis

Tactile agnosia , or astereognosis - this is the inability to detect objects placed in the hand by touch with eyes closed, provided sensitivity is intact. Astereognosis is divided into 2 types: primary astereognosis and secondary astereognosis. Tactile agnosia occurs when the parietal cortex is damaged, most often the superior parietal lobule. Tactile sensitivity and muscle-articular sensation are not affected in primary tactile agnosia. In secondary astereognosis, the muscle-articular sense and tactile sensitivity are affected. The stage of synthesis of elementary sensory sensations is disrupted. A patient with tactile agnosia can describe individual properties of an object, but cannot perceive it as a whole.

Olfactory agnosia

Olfactory agnosia is a disorder of recognizing familiar objects or substances by smell.

Taste agnosia

Taste agnosia - this is a violation of the recognition of substances by their taste while maintaining taste and smell. Taste agnosia and olfactory agnosia develop due to extensive lesions of the mediobasal areas of the temporal lobe cortex.

Pain agnosia

Pain agnosia - disorder of perception of painful stimuli. Dysesthesia- violation of the perception of an injection as a touch.

With the agnosias discussed above, patients have impaired recognition of external stimuli. Some types of agnosia are associated with disturbances in a person's perception of his own body.

Anosognosia

Anosognosia - this is the lack of a critical assessment of one’s defect. Anosognosia observed more often with damage to the right parietal lobe of the brain. Patients do not critically evaluate their defects such as impaired vision, decreased hearing, paralysis, and paresis. Often with anosognosia, patients deny their illness.

Anton syndrome

Anton syndrome is a type of anosognosia in which a patient who has serious vision problems very persistently denies the presence of these problems. Anton syndrome It was first observed in 1898 by a psychiatrist and neurologist from Germany, Anton, after whom this syndrome is named. Anton himself called this disease cortical blindness. Anton syndrome observed when the posterior areas of the cerebral cortex are damaged, reflex relationships between the diencephalon and the occipital zone of the cerebral cortex are disrupted. Basic symptoms of Anton's syndrome: visual impairment, denial by the patient himself of visual impairment, lack of critical perception of his condition, violent fantasies, verbosity, tendency to fiction.

Autotopognosia

Autotopognosia - this is the difficulty of recognizing one’s own body and its parts, violations of the body diagram. Autotopognosia refers to somatoagnosia. It seems to a person that a person has 6 arms, 8 legs, 2 heads, a square head, and arms with tentacles. The patient cannot distinguish between the right and left sides of the body, cannot show parts of his body, and the performance of Ged's tests is impaired. A patient with damage to the dominant hemisphere of the brain does not distinguish between the left and right halves of the body; with damage to the subdominant hemisphere of the brain, he believes that he does not have an arm or a leg, or he cannot control these limbs.

Polymelia

Polymelia is a condition in which a person seems to have many arms or legs.

Finger agnosia, Gerstmann's syndrome

Finger agnosia - this is the inability to distinguish one finger from another, while the muscular-articular sense is preserved. The digital one is called Gerstmann's syndrome. Autotopognosia is observed with damage to the parietal cortex and its connections with the thalamus in the right hemisphere. Finger agnosia, disturbance of orientation on the left and right, according to Sarklinik, are also often observed in left-hemispheric parietal pathological processes.

Secondary disturbances of gnosis

Secondary disturbances of gnosis observed with damage to the anterior parts of the brain. Secondary disorders of gnosis are characterized by fragmented perception of sensory images. They latch on to a certain image and think it is correct. For example, a patient bathes in a bath without water, but thinks that it is filled with water. With dynamic disturbances of gnosis, the time for recognition of sensory images increases. When the deep activating nonspecific systems of the brain are damaged, positive effects of external stimulation of attention, fragmented perception, and fluctuations in disorders can occur.

Letter agnosia

Letter agnosia characterized by misrecognition of letters. The patient's oral speech is preserved, but he has (word blindness) and (writing disorder). Letter occurs when the occipital parts of the dominant hemisphere of the brain are affected.

They even make films about the disease “agnosia.” Everyone remembers the Spanish film " Agnosia"directed (and composer) Eugenio Mira (2010) featuring starring Eduardo Noriega. The film "Amnesia" tells the story of the daughter of a wealthy industrialist and businessman Joan Praca, who suffers from agnosia. It is difficult to live and keep secrets when vision and hearing are in perfect order, but the brain does not want to form understandable auditory and visual images from signals coming from the outside. Who is the main villain of the thriller - Vicente, Carles or someone else?

Agnosia treatment, how to treat agnosia

Sarklinik conducts treatment of agnosia in Sartov, Russia . Sarklinik knows how to treat agnosia in Saratov.

. There are contraindications. Specialist consultation is required.
Photo () Dcopy | Dreamstime.com \ Dreamstock.ru The people depicted in the photo are models, do not suffer from the diseases described and/or all similarities are excluded.

The health of the brain entails the health of the whole body. When a person begins to distortly perceive the world around him, many begin to have ambivalent attitudes towards this phenomenon. Someone understands that a person is sick and needs treatment. The rest treat phenomena visible only to humans as miracles that need to be believed. Agnosia can become a serious condition. The types, causes, symptoms and methods of treatment of this disease will be discussed in this article.

Agnosia

You need to define what agnosia is. This is a disease of sensory perception of the surrounding world, in which a person remains conscious. Often this disease manifests itself in disorders of brain function. Violation of the projection (primary) departments leads to a distortion of sensory perception - vision, hearing or pain threshold deteriorates. When the secondary sections are damaged, the ability to receive and interpret external information is lost.

Agnosia refers to impaired perception of the surrounding world, while the sense organs themselves are functioning properly. In other words, this can be called hallucinations, delusions, confusion. The senses are working properly. The problem lies in the brain, which does not perceive or distorts information, giving the wrong answer. A person sees, hears or feels something that does not exist.

Sometimes agnosia is a symptom of another disease, and does not act as an independent disease. For example, poisoning or poor circulation in the brain leads to similar syndromes.

This condition is often observed due to toxic exposure. For example, after using drugs, alcohol or poisoning with poisons or toxins. Parts of the brain begin to change their functioning, which is why a person imagines something that is not there.

It should be noted that information in a distorted form can come both from outside and from the body. The sensation of worms crawling under the skin or the presence of foreign bodies inside the body are some of the signs of agnosia, when a person imagines something that is not really there.

The patient himself may be completely healthy, especially his organs of perception. Here it is necessary to find out the reasons why the brain incorrectly perceives or interprets information. It also eliminates the possibility of brain damage.

Types of agnosia

The brain is responsible for the perception of information by various organs; accordingly, many types of agnosia can be distinguished here:

Visual (optical). Manifests itself in failure to recognize familiar objects, as well as their properties. However, the person is not blind. Often develops against the background of other diseases, such as Alzheimer's disease. Its types:

Subject-visual. When a person feels that his vision has deteriorated and he is unable to recognize the object he is looking at.
Spatial-visual (topographic). A person cannot navigate in space, gets lost, does not recognize familiar places, and also cannot recognize the relationship of objects to each other.
Metamorphopsia. A person perceives objects in a distorted form. Macropsia – seeing objects in an enlarged form. Micropsia – seeing objects in a reduced form.
Prosopagnosia (agnosia for faces). It seems to a person that he cannot recognize familiar people due to the fact that he has poor eyesight. In fact, his vision is good, but his brain does not recognize familiar faces.
Simultaneous (simultaneous). The inability to fully or holistically perceive a complex of sensory images and failure to recognize an image by its parts.
Agnosia for colors. A person is not able to recognize the color of the objects he looks at. At the same time, he remembers what colors certain objects have, if you ask him from memory.
Neglect (ignoring half of the space). A person does not see the part of space that opens in front of him.

Auditory agnosia. It manifests itself in the fact that a person cannot recognize familiar sounds, although his hearing is excellent. There are these types:

Verbal. When a person does not understand the words he knows.
Amusia. A person does not recognize familiar melodies and tones of voice.
Letter. The person does not recognize letters. Dysgraphia (writing disorder) and dyslexia (word blindness) can also be seen here.

Tactile agnosia (astereognosis). A person is not able to recognize objects that are placed in his hands. He can describe the properties of an object, but is not able to combine them into a whole and recognize which object is in his hands. The symptom is divided into primary and secondary. With the primary symptom, tactile sensitivity and muscle-articular perception are not impaired, unlike the secondary symptom.
Olfactory agnosia. A person does not recognize or perceive familiar smells.
Taste agnosia. It manifests itself in the fact that a person does not recognize familiar tastes. Often develops together with olfactory agnosia, since the parts of the brain of these centers are located nearby.
Pain agnosia. Manifests itself in the absence of correct perception of painful stimuli. It occurs in the form of dysesthesia - failure to perceive an injection as a touch.

In addition to external stimuli that the brain perceives through the senses, there are internal factors. What types of agnosia are discussed here?

Anosognosia. A person does not perceive the defects of his body, there is no critical assessment. This is a condition in which a person denies having an illness, such as impaired vision or hearing loss. Here we consider Anton's syndrome, in which a person has impaired vision, and the patient denies this disease.
Anodiaphoria. It is expressed in a person’s indifferent attitude towards his defect (illness). A person realizes that he is sick, but does not experience any feelings about it.
Autotopognosia. A person perceives his own body incorrectly. It may seem to him that he has 2 heads or 4 legs. Refers to somatoagnosia (impaired perception of one's body). The types discussed here are:

Finger. It is observed with a distorted perception of the number or location of fingers, both in oneself and in others. A person cannot understand how many fingers he has, or does not distinguish left from right.
Polymelia. A person may feel like they have many legs or arms.

Visual agnosia

The most common type of distorted perception of the world is visual agnosia. This is a person’s inability to perceive familiar objects, navigate in space, see layered contours, etc. If you ask a patient to draw an object, he will not be able to do this, because he does not recognize the phenomenon as a whole. He can see individual details, contours, strokes, but the whole picture will not emerge.

The cause of this type of agnosia is damage to the occipital-parietal region. There are types of agnosia that have already been outlined above: agnosia for faces, spatial agnosia, associative and apperceptive agnosia.

Lisauer's apperceptive agnosia manifests itself in the fact that a person is unable to recognize complex objects. For example, he will be able to recognize a ball, but more complex objects with many details will become unrecognizable. The patient is able to recognize contours, shapes, colors, etc.
Balint syndrome manifests itself in “mental gaze paralysis.” A person is not able to recognize several objects that pass his gaze. He also fails to turn his gaze to the object that is on the periphery.
Associative agnosia is the inability to recognize objects because they are not clearly visible to the person.

With all types of visual agnosia, a person has excellent vision. The problem lies in the brain, which distorts the information entering it.

Because people are rarely aware of their own illness, they may fantasize. Their eyes see, their brain distorts, and then their imagination kicks in. What a person does not understand can become something else. This attracts impressionable people who believe in miracles. Hallucinations and delusions may be observed here if visual agnosia appears against the background of an existing mental illness.

Causes of agnosia

What could be the reasons that a person perceives the world around him distortedly, and his senses are completely healthy? Since the brain is responsible for the perception and processing of information, the causes of agnosia lie in damage or disruption of the functioning of its departments.

Damage to the parietal or occipital lobe of the brain is predominantly noted. This may happen due to:

Circulatory disorders in the brain (stroke).
Tumors in the brain.
Chronic disturbance of blood circulation in the brain with the development of dementia.
Consequences of traumatic brain injuries, blows, injuries.
Inflammation of the brain (encephalitis disease).
Alzheimer's disease, in which amyloid protein accumulates in the brain rather than being destroyed.
Parkinson's disease, in which tremors, muscle stiffness, and neuropsychological disorders develop.
Failed brain surgery.
Heart attack.
Degeneration of brain tissue.

In right-handed people, the disease develops against the background of damage to the left hemisphere, and in left-handed people - to the right.

Any damage or dysfunction of the brain leads to the fact that a person perceives incoming information distorted. Such disturbances can be observed not only as a result of active influence on the brain, but also after a long period of unconsciousness.

Don't forget about the effects of various substances on the brain, such as drugs or alcohol. Here, both with the organs of perception and with the functions of the brain, everything is normal. However, the influence of certain substances distorts the perception of the world for some time. On the one hand, this may seem funny to some lovers of the “unusual and spicy.” On the other hand, constant exposure of the brain to harmful substances can lead to disorders.

Symptoms of agnosia

Agnosia can be diagnosed by observing the patient, as well as by conducting a number of instrumental studies that confirm dysfunction of the brain. Symptoms of agnosia that cannot be hidden by patients become striking here:

Disorientation in space. A person is not able to recognize many objects in space and their relationships. Also cannot perceive himself in space.
Denial of the disease. A person does not perceive the fact that he is sick.
Indifference to the presence of illness.
Impaired recognition of objects by touch. Some details may not be perceived, as well as the object as a whole.
Impaired recognition of sounds.
Distorted perception of one's body, inability to tell how many legs it has, how long its fingers are, etc.
Failure to recognize familiar people.
Inability to perceive different objects as a whole. He can see objects, but is not able to tell in what relation they are (for example, a glass on a table: he sees both the glass and the table, but is not aware that the glass is on the table).
Ignoring half of the visible space.

Thus, the symptoms depend entirely on the type of agnosia. At the same time, the patient may think that everything is fine with him, only his hearing or vision has decreased. He will blame the decrease in the acuity of perception of the organs, and not the violation of perception by the brain.

The patient is not able to recognize his illness himself, not only because of an incorrect interpretation of what is happening, but also because of the inability to understand what is real and unreal. Only an answer from the outside world can make you think that something is wrong. Relatives may notice that a person recognizes or sees something incorrectly. In the early stages, symptoms can be stopped or eliminated. If the disease has progressed to the second stage, then we can talk about the impossibility of eliminating agnosia.

Treatment of agnosia

To date, there is no effective treatment for agnosia. We are talking about damage or lesions of the brain, so the main methods and manipulations are aimed at restoring these departments:

Drugs are prescribed that improve blood circulation in the brain. Blood pressure is controlled.
Surgeries are performed to remove tumors, ruptures, etc. from the brain. Without surgery, pills will not help in this case.
Medicines that help restore neuropsychological functions.

The patient is constantly under consultation with a neuropsychologist.

Many doctors perceive this disease as ordinary. The patient simply needs to be re-taught the skills that were lost. If a person suffers from visual agnosia, then he is again taught shapes and colors, the relationship of objects in space, etc. If auditory agnosia has developed, then the person is taught sounds.

We are talking about damage that is difficult to restore with modern medicine. However, in some cases, such manipulations are effective and help patients adapt to life. The exception is somatoagnosia, which requires constant medical supervision.

If agnosia is a consequence of a mental illness, then treatment is aimed at eliminating this disease. Since brain diseases are not always completely cured, the restoration of its parts also becomes incomplete.

If agnosia is the result of abuse of toxic substances, then it is recommended to protect the patient from alcohol, poison, drugs and other substances. The body is cleansed of these substances, as well as taking medications that improve brain function.

Lifespan

Is it possible to talk about whether agnosia will somehow affect a person’s life expectancy? In fact, the disease itself does not kill, but the cause of death may be the cause that caused the agnosia. If the brain is affected by some kind of infection or blood circulation in it is not restored, then an unfavorable prognosis is possible.

The mental health website notes the shortest cure time for the disease at 3 months. Depending on the age, severity and type of the disease itself, recovery can take up to a year or more. The nature of the lesion and the possibility of restoring brain function become important. In some cases, a person may not be completely cured. With somatoagnosia, we cannot talk about complete recovery at all.

If a person is not treated, then the outcome may be disappointing. In such cases, the person becomes completely antisocial. He cannot communicate effectively with people or do any work.

Preventive measures are not defined here due to the suddenness of the onset of the disease. However, doctors recommend:

Monitor your blood pressure.
Heal from any diseases of the body.
(alcohol, drugs, etc.).
Lead an active and healthy lifestyle.
Eat well.
Consult a doctor if strange symptoms similar to agnosia appear.

The disease can remove a person from social life for a long time. It becomes an obstacle to successful contact with other people. Medicine continues to study this topic to help people with their disease. However, only preventive measures today can help prevent agnosia.

Agnosia is a pathological condition associated with a violation of various types of perception, subject to the preservation of consciousness and sensitivity. The reason for this is damage to the secondary parts of the cerebral cortex, which are responsible for the analysis and synthesis of information.

There are different types of agnosia depending on the analyzer in the regulation of whose activity disturbances occurred (auditory agnosia, tactile agnosia, visual agnosia, olfactory agnosia, spatial agnosia and others).

This condition is diagnosed during a neurological examination.

Treatment of agnosia consists of treating the underlying disease.

Causes of agnosia

Agnosia is caused by damage to the projection-associative parts of the cerebral cortex, which are part of the cortical level of the analytical systems.

In this case, a person retains elementary sensitivity, but loses the ability to analyze and synthesize information received from the analyzer, which results in a violation of one or another type of perception.

Damage to the cerebral cortex can result from: cerebrovascular accident, Alzheimer's disease, toxic encephalopathy, subacute sclerosing panencephalitis.

Types of agnosia

The following types of agnosia are distinguished:

Visual agnosia - occurs when the occipital cortex is damaged. In this case, the person does not lose visual acuity, but at the same time cannot recognize objects or distinguish the characteristics of objects.

Visual agnosia, in turn, is divided into:

object - there is a violation of object recognition while maintaining vision function. Patients describe individual signs of objects, but cannot determine which object is in front of them;
simultaneous - there is a functional narrowing of the visual field to one object. Patients perceive only one semantic unit at a time;
agnosia for faces (prosopagnosia) – the process of recognizing familiar faces is disrupted. Patients distinguish the face as a whole object and its parts, but cannot say who is in front of them;
color agnosia, that is, the inability to determine whether a color belongs to a specific object or to select the same colors;
agnosia caused by optomotor disorders, that is, the inability to direct the gaze in the required direction while maintaining the function of eye movement. The patient finds it difficult to fix his gaze on a given object, it is difficult for him to read;
weakness of optical concepts - the inability to represent an object, as well as describe its properties.

Auditory agnosia - develops with damage to the temporal cortex. If the left side is affected, there is a violation of the discrimination of speech sounds, which leads to speech disorder. If the right side is affected, the patient does not recognize familiar noises and sounds, or amusia develops, when the ear for music disappears. In this regard, they distinguish:

simple auditory agnosia - lack of ability to identify simple sounds and noises - rustling paper, knocking, gurgling, clinking of coins;
auditory-verbal agnosia - lack of ability to recognize speech, which is perceived by the patient as a set of sounds unfamiliar to him;
Tonal agnosia is the inability to distinguish the expressive aspects of the voice. Patients do not perceive the tone, timbre, or emotional coloring of the voice. But at the same time they understand speech.

Tactile agnosia develops when the central gyrus located in the posterior part of the cortex is damaged. Tactile agnosia is manifested by a lack of recognition of objects by touch (with eyes closed) or a lack of recognition of the texture of an object. In this regard, a distinction is made between object tactile agnosia and tactile texture agnosia.

Spatial agnosia is the inability to determine various spatial parameters. Stands out:

violation of topographic orientation - inability to navigate in a familiar place. The patient cannot find his home, is lost in his apartment, but his memory is preserved;
Depth agnosia – the inability to correctly localize objects in space, to determine parameters closer to further;
unilateral spatial agnosia - a disorder in which loss of one half of space occurs, usually the left;
impaired stereoscopic vision;

Somatoagnosia is a violation of recognition of parts of one's body, the inability to assess their location relative to each other. These include: anosognosia (lack of awareness of one’s own illness) and autotopagnosia (failure to recognize individual parts of the body and impaired perception of them in space).

Impaired perception of movement and time - the patient has an incorrect perception of the movement of objects and the passage of time.

Olfactory, gustatory, and finger agnosia are also distinguished.

Diagnosis of agnosia

The diagnosis of agnosia is made based on medical history (trauma, stroke, tumor) and the clinical picture of the disease. Special tests are also performed to determine the type of agnosia.

The patient is asked to identify simple objects using various senses. If the doctor suspects denial of half of space, then he asks the patient to identify paralyzed parts of his body, or objects in different parts of space.

Conducting a neuropsychological examination helps determine the presence of more complex types of agnosia.

Brain imaging methods (MRI or CT) are also used to establish the nature of central lesions (hemorrhage, infarction, massive intracranial process) and to identify areas of cortical atrophy.

To identify primary disorders of certain types of sensitivity, a physical examination is performed.

Treatment of agnosia

There is no specific treatment for this pathological condition. Its treatment comes down to treatment of the underlying disease, which has led to damage to certain areas of the cerebral cortex. Of great importance in this case is a consultation with a neuropsychologist, which can help the patient adapt to his defect and compensate for it at least partially.

In some cases, agnosia may resolve spontaneously. If there are irreversible changes in the brain, patients are forced to live with their disorder throughout their lives.

Defectologists are involved in correcting this disorder.

Rehabilitation with the help of an occupational therapist or speech therapist can help the patient achieve compensation for the disease.

Whether recovery occurs and how complete it is is determined by the size and location of the lesions in the brain, the degree of brain damage, and the age of the patient.

Most often, recovery occurs within a period of three months to one year.

Thus, agnosia is not an independent disease, but a certain complex of symptoms indicating damage to one or another secondary part of the cerebral cortex. This condition is not curable, only the underlying disease that caused agnosia is treated, the degree and success of which determines the prognosis for the restoration of lost perception functions.

Agnosia is a disease characterized by a violation of certain types of perception, resulting from damage to the cerebral cortex and nearby subcortical structures.

When the projection (primary) parts of the cortex are disrupted, sensitivity disorders occur (hearing loss, impaired visual and pain functions). In cases where the secondary sections of the cerebral cortex are affected, the ability to perceive and process the information received is lost.

Auditory agnosia

Auditory agnosia occurs as a result of damage to the auditory analyzer. If the temporal part of the left hemisphere has been damaged, then a disorder of phonemic hearing occurs, characterized by a loss of the ability to distinguish speech sounds, which can lead to a disorder of speech itself in the form of sensory aphasia. In this case, the patient’s expressive speech is a so-called “word salad”. Disturbances in writing from dictation and reading aloud may also occur.

If the right hemisphere is damaged, the patient ceases to recognize absolutely all sounds and noises. If the anterior parts of the brain are affected, then all processes proceed with the preservation of the auditory and visual systems, but with a violation of the general perception and concept of the situation. Most often, this type of auditory agnosia is observed in mental illnesses.

Arrhythmia of auditory agnosia is characterized by the inability to understand and reproduce a specific rhythm. Pathology manifests itself when the right temple is affected.

A separate type of auditory agnosia can be identified as a process that manifests itself as a violation of understanding the intonation of other people’s speech. It also occurs with right temporal lesions.

Visual agnosia

Visual agnosia is a violation of the ability to recognize objects and their images with complete preservation of vision. Occurs with numerous lesions of the occipital cortex. Visual agnosia is divided into several subtypes:

Simultaneous agnosia is a violation of the ability to perceive a group of images that form a single whole. In this case, the patient can distinguish between single and complete images. Develops as a result of damage to the area where the occipital, parietal and temporal lobes of the brain meet;
Color agnosia is the inability to distinguish colors when color vision is intact;
Letter agnosia is the inability to recognize letters. This pathology is called “acquired illiteracy.” While speech is preserved, patients can neither write nor read. Develops when the dominant hemisphere of the occipital region is damaged.

Tactile agnosia

Tactile agnosia is a violation of the recognition of shapes and objects by touch. Appears after damage to the parietal lobe of the right or left hemispheres. There are several types of agnosia of this nature:

Object agnosia is a pathology in which the patient cannot determine the size, shape and material of an object, while he is able to determine all its signs;
Tactile agnosia is the inability to recognize letters and numbers drawn on the patient’s hand;
Finger agnosia is a pathology characterized by a violation of identifying the names of the fingers when touching them with the patient’s eyes closed;
Somatoagnosia is the inability to identify parts of the body and their location in relation to each other.

Spatial agnosia

This type of spatial agnosia is characterized by the inability to recognize spatial images and navigate in place. In such situations, the patient cannot distinguish right from left, confuses the location of the hands on the clock and swaps letters in words. Manifests itself as a result of damage to the parieto-occipital lobe. Diffuse disturbances of cortical structures can lead to a syndrome in which the patient ignores half of the space. With this type of spatial agnosia, he completely does not notice objects or images located on one side (for example, on the right). While redrawing, he depicts only part of the drawing, saying that the other part does not exist at all.

Anosognosia

Among all other forms of this pathology, a special type of agnosia is distinguished - the so-called anosognosia (Anton-Babinsky syndrome). This pathology is characterized by the patient’s denial of his disease or reduced criticality of its assessment. Occurs with lesions of the subdominant hemisphere.

Diagnosis, treatment and prognosis for agnosia

Diagnosis of agnosia occurs during a comprehensive neurological examination; its exact type is revealed using special tests.

Treatment of this symptom complex occurs during the treatment of the underlying disease, and therefore is characterized by significant variability. Just like treatment, the prognosis depends on the severity of the underlying pathology. In medical practice, cases of both spontaneous cure of agnosia and prolonged course of the disease, almost lifelong, have been described.