Risks and consequences of ischemic strokes localized in the right hemisphere. Features of damage to the right and left hemispheres Features of damage to the right and left hemispheres gnosis

The topic of strokes has recently become more than relevant. According to statistics, every 90 seconds one of the residents of Russia experiences a stroke with different locations anatomically and, as a result, different consequences and prognosis physiologically. There is a dependence of the incidence of the disease on race, nature of work (mental or physical), age and lifestyle. Today, stroke ranks second as a cause of death according to WHO. The first place belongs to IHD (by the way, also a vascular disease). The third one is cancer.

Strokes are the scourge of modern society

What is a stroke?

A stroke is a sudden blockage of blood circulation to the brain. There can be several mechanisms for the development of this condition: blockage or compression of a vessel, or rupture of a vessel with the ensuing consequences.

If there is a violation of the integrity of the vessel, then a hemorrhagic stroke is implied. When the blood flow in the vessels of the brain is disrupted due to a blood clot or compression (for example, a tumor or hematoma), the diagnosis is ischemic stroke. The mechanism of development of the disease is very similar to a heart attack (most often, vascular thrombosis is the cause of both stroke and heart attack). Only in the first case everything happens in the vessels of the brain, and in the second - in the coronary arteries (heart vessels). We can say that a stroke is a cerebral infarction, in which there is also an area of ​​necrosis due to metabolic disorders and hypoxia of surrounding tissues.

It is known that one of the most important tasks of blood is the delivery of oxygen to organs and tissues. During a stroke, blood abruptly stops flowing to the brain tissue; due to lack of oxygen, large areas of nerve cells suffer and die, with corresponding consequences for the patient.

To understand the seriousness of the condition and the mechanism of the process, you need to know that each part of the brain is responsible for a specific function(s). Depending on the location and volume of damaged tissue, the performance of one or another function is affected.

Risk factors

Some risk factors cannot be influenced (race, gender, heredity, age, season, climate).

It is quite possible to correct other risk factors to prevent the possibility of a stroke and its consequences. For example, physical inactivity, obesity, stressful situations, arterial hypertension, lipid metabolism disorders, diabetes mellitus, alcohol consumption and smoking.

Symptoms

It is also known from biology lessons at school that a person has two hemispheres of the brain: the left and right hemispheres. In this case, the left side of the brain controls the right side of the body, and vice versa. That is, if a patient has paresis of the left upper limb, for example, then the source of damage is in the right side of the brain.

How to recognize a stroke?

Symptoms or consequences can be divided into general for strokes, regardless of the cause (blockage, compression or rupture), localization (right or left) and focal (characteristic of damage to a specific area of ​​the brain). It is also possible for a stroke to be extensive (a large part of the brain is damaged) or focal (a small area of ​​the brain is damaged). Common symptoms will be headache that comes on suddenly, dizziness, nausea, tinnitus, loss of consciousness, tachycardia, sweating, feeling hot, depression.

A characteristic feature, and at the same time a problem for recognizing a stroke in the right hemisphere, is the absence of speech impairments (in contrast to symptoms with damage to the left hemisphere of the brain).

Therefore, in cases of right-sided stroke with mild symptoms, they rarely seek medical help in the first days of the disease, when they can significantly influence the outcome of the disease by preventing consequences.

It must be said that the picture of this condition is bleak, since the recovery period is complicated by neuropsychopathological syndromes that usually occur in the patient. Complete restoration of lost functions is possible with minor lesions in the right hemisphere of the brain.

In case of a major stroke, after treatment, a successful prognosis is given if the patient can care for himself. As a rule, the consequences of such a stroke are disability, although there are exceptions to any rule.

When an extensive stroke is localized in the right hemisphere, spatial disorientation occurs, and the ability to objectively assess the shape and size of objects (including one’s own body in space and time) is lost. The patient’s left visual field disappears, that is, what healthy people see with peripheral vision (on the left), a patient with a right-sided stroke does not see. The focal symptoms of a right-sided stroke are paresis or paralysis of the limbs on the left; amnesia for recent events, drooping down the left corner of the mouth; spatial disorientation. In left-handed people, the consequences of a stroke may be impaired speech function.

Facial distortion during stroke

The emotional sphere suffers, behavior changes: it becomes inappropriate, inadequate, swagger appears, tact and correctness are absent. The difficulty in treatment and the likelihood of lack of effect when the right hemisphere is involved is very high, since patients are not aware of their condition, do not understand the danger and are not committed to recovery. Patients have no perception of reality. Such patients do not understand that they have problems with the ability to move, there may even be a feeling that there are many limbs, not two, so treatment can be very problematic.

Nevertheless, right-hemisphere strokes in right-handed people have a more favorable prognosis for the restoration of motor and cognitive functions, in contrast to damage to the left hemisphere, which is associated with significant speech and intellectual-mnestic impairments.

Treatment and rehabilitation

During these difficult periods, you will need the support and understanding of family and friends.

It is necessary for doctors to stop the acute condition. At the same time, it is necessary to influence all possible links in pathogenesis. Therefore, antiplatelet agents, anticoagulants, enzymes and neuroprotectors are necessarily included in the treatment regimen. Treatment should take place in a hospital under the supervision of a doctor. The prognosis depends on the location of the lesion - in the right or left hemisphere, the extent of the process, concomitant diseases, the patient’s focus on recovery and the severity of the consequences.

A set of special exercises is selected individually for each patient

Rehabilitation measures must be comprehensive. The earlier treatment and rehabilitation are started, the greater the chances of returning the patient a decent quality of life and preventing consequences. At the same time, medications are continued, exercise therapy, massage, and physiotherapy are prescribed.

Doctors' prognoses for a major stroke of any location are disappointing; you need to be prepared for serious consequences; the possibility of coma cannot be ruled out. But the chances of survival are enormous with proper treatment and care.

Prevention

Prevention of strokes consists of monitoring and correcting factors that can provoke a vascular accident. In case of arterial hypertension, it is necessary to take medications that maintain blood pressure at the required level. It is necessary to eliminate bad habits and stressful situations. As part of drug support, it is possible to use antiplatelet agents - blood thinning drugs; as well as cerebroprotectors and drugs that improve microcirculation. It is important to lead an active lifestyle, while controlling psycho-emotional stress.

Comprehensive stroke prevention

Ischemic stroke is not an independent, sudden condition, but a consequence of some process, therefore the key to successful prevention is the timely detection and prevention of such consequences and processes.

Physiologists have always treated animal psychology with a certain distrust. It was believed that it was possible to penetrate into the thoughts of creatures that do not have a language, and not a single animal - neither the silent intellectuals of the sea, dolphins, nor the talented imitators of sounds, chatty parrots - could master speech. Speech is considered one of the main, most important differences between humans and animals. And although from time to time there are scientists who undertake to either teach the four-legged inhabitants of our planet language, or to find among them such highly developed creatures that, secretly from us humans, have been using speech for a long time, they have not been able to shake skepticism for a moment. Even when articles about “talking” monkeys appeared on the pages of newspapers and an unimaginable journalistic boom began, high academic spheres remained coldly indifferent. Teaching chimpanzees language turned out to be such an unscientific problem that there was no desire to issue a refutation of the hype.

In 1859, Charles Darwin completed the most important work of his life, “The Origin of Species.” His main goal was to show the commonality between animals of different levels of development, as well as between animals and humans. To do this, Darwin collected unique material confirming the similarities in body structure, behavior and psyche.

Of course, there are differences. It is not without reason that Darwin’s followers, convinced of the origin of man from animals, have long become accustomed to the idea of ​​a huge gap between us and our smaller brothers, which formed when our distant ancestor climbed down from a tree and began to learn to walk on two legs. This version suited the Christian church quite well. According to its pillars, it irrefutably testified to the divine origin of man and completely discredited Darwinism.

The "talking" monkeys were unable to break this barrier. Meanwhile, chimpanzees, in a very short period of time, accumulated a vocabulary comparable to the volume of words that two or three year old children have at their disposal, and mastered the skill of constructing phrases of two, three or more words. The monkeys turned out to be able to invent new words on their own, understand metaphors and even swear, independently selecting suitable expressions for this, and yet they could not convince most experts that the communication system they had acquired could be considered a language.

Without going into details of the discussion that arose on this issue, I will say that, from the point of view of I. Pavlov’s teaching on higher nervous activity, the successes of chimpanzees cannot be called anything more than the initial stage of language acquisition, so that in this indicator there is a difference between the animal and the person. there is no insurmountable gap. Chimpanzees rebuffed church dogma in the most unequivocal way in their monkey language.

Success in teaching monkeys to speak did not come immediately. They couldn't cope with sound language. But when they decided to use sign language, things went smoothly. We already know that speaking sign language in humans is controlled by the right hemisphere. No one yet knows how speech is organized in the chimpanzee brain. The speed with which monkeys learn the names of objects and actions and generalize them, extending them to all homogeneous objects and actions, shows that many generalizations of a fairly high order existed in their brains long before learning began.

There is no reason to doubt that generalizations and some concepts are also formed in the brains of deaf-mutes who have never been taught any speech skills. But in which hemisphere of an untrained deaf-mute these concepts and generalizations are stored is also still unknown. They must be based on visual images, which means they can be expected to be produced by a “parasite.”

Turning off the function of the right hemisphere does not disturb time orientation; the subject perfectly remembers the year, month and date, and by looking at the watch dial, even if there are no numbers on it, he can tell by the position of the hands what time it is. All this information is stored in speech memory. But the orientation in the environment according to its specific features is so disturbed that it becomes difficult for the subject to understand the colored landscapes. Instead of simply saying that it is winter in the picture, he will answer that since there is snow, then in all likelihood it is winter.

Orientation in space is even more impaired. Although the subject remembers very well that he is being treated in the hospital named after N.A. Semashko was placed in the seventh ward of the third department; he will not be able to return to it from the treatment room on his own. It would be pointless to ask him about how to get there, or ask him to sketch out a plan.

When the focus of the disease is localized in the right hemisphere, patients forget the layout of their apartment, much less are able to navigate the new environment of the hospital department. They sometimes cannot even find their own bed in the ward on their own. They are completely incapable of sketching out a plan of a long-familiar room, or drawing from memory such ordinary objects as a teapot or glasses, or well-known animals from childhood like a dog or a horse.

Orientation in the space located to the left of the patient is especially severely disrupted. He does not have any impressions of what is there. If he is asked to count the people present in the room, the patient does not notice the persons on the left. In search of the book he needs, he looks through only the right parts of the shelves on the rack; he will look for his suit in the right compartment of the closet, and for dishes in the right compartment of the sideboard. In general, for the patient, the left half of the surrounding world and the left half of his own body cease to exist.

The left-hemisphere subject loses the ability to estimate time. He doesn't know how long he's been in the treatment room. To any question, he will most often answer that half an hour has passed, but in fact it may turn out that he was only brought here five minutes ago or, conversely, he has been in the treatment room for more than an hour.

When the parietal areas of the right hemisphere are damaged, such a specific function as recognition of individual characteristics of familiar objects is disrupted. It becomes difficult for the patient to determine by appearance what material the object presented to him is made of: glass, wood, metal, fabric. A forester who worked all his life on a farm near Moscow became ill and stopped recognizing tree species. I couldn’t even distinguish a spruce from a birch until I touched a branch and pricked myself on the needles. It is interesting that such patients are able to copy pictures, but cannot draw from memory and often do not recognize what they themselves are drawing.

Humor is a purely human property. Psychologists consider it one of the most important manifestations of highly developed intelligence. Patients with damage to the right hemisphere, looking at cartoons, often do not see anything funny in them, even if they are able to characterize the depicted situation quite well and completely. Captions of any nature accompanying the drawings greatly facilitate the ability to grasp the humorous nature of the image. But the analysis of texts, their meaning and content is a function that belongs exclusively to the left hemisphere. So the emotional assessment of the caricature in this case is entirely due to the help of the linguistically savvy half of our brain.

Is the right hemisphere capable of mental activity and abstraction? Of course, it is capable, only its abstractions are not connected with logical constructions, they are not put into words. Like everything right-hemisphere, they are figurative in nature. If we need to create a generalized image of an object that has such a complex shape that it is impossible to find verbal symbols for it, this operation is performed in the right hemisphere.

Based on visual images and generalizations, the right hemisphere predicts and extrapolates the further course of events. Crossing a country highway and seeing an approaching car, the “parasite,” based on an analysis of our own speed and the speed of the car moving along the highway, extrapolates where each of us will be in 3...4 seconds and makes a conclusion whether to cross the road or let the car pass first .

The ability to extrapolate the entire circle from a small segment of a curve is also provided by the right hemisphere. Thanks to his work, having become familiar with the construction details of a collapsible house, we can imagine what it will look like when assembled. This helps us choose the appropriate cut in the store and quite accurately imagine what a suit made from it will look like. Abstractions and generalizations of the right hemisphere are extremely difficult to describe in words. This is why we know so little about them and why it is so difficult to talk about them.

Imaginative thinking seems to us less fruitful for the analytical perception of the world. For logical comprehension and forecasting of the further course of events, it has another drawback - the tendency to see the world in black terms. Our right hemisphere can quite deservedly be called the “knight of the sad image.” It is not without reason that after its functional shutdown, the mood of the subjects improves sharply. They become more cheerful, smiling, begin to treat others with more kindness, and they develop a penchant for jokes.

The effect of temporarily switching off the right hemisphere on the formation of mood is striking. After a right-sided electric shock, the first smile often appears in the subject even before consciousness has returned to him. How important this effect of electric shocks is can be judged by the fact that among the patients who need this method of treatment, there are many people with various forms of depression. In combination with drug treatment, electric shock produces a lasting positive effect.

One of the most common symptoms of right-sided brain damage is euphoria, an increased joyful mood, a feeling of contentment and well-being, accompanied by an optimistic assessment of the environment that does not correspond to objective circumstances. The patients are complacent; they apparently do not realize the severity of their illness; in any case, this does not cause them any unpleasant sensations. In general, these patients do not experience deep tragic experiences that cause suffering in healthy people. Doctors perceive the occurrence of anxiety or concern in a patient as a favorable symptom indicating the possibility of recovery.

People are very different from each other in character, temperament, general emotional mood, and each of us has more than once experienced a change in mood, sometimes seemingly completely without cause. Apparently, our emotional mood is determined by the predominance of the tone of one of the hemispheres. Depending on which of the twins takes over, cheerful, optimistic or sad, sad music is ordered, and our daily life flows to its accompaniment.

Some patients experience hallucinations. It is interesting that visual and auditory senses more often occur with damage to the right hemisphere, while olfactory and gustatory senses with damage to the left hemisphere are never observed at all. And the nature of visual hallucinations differs significantly from similar visions that occur with a disease of the left half of the brain. They are not certain. Patients say that they saw some people who seemed familiar to them, but they did not understand who it was. If hallucinations bring visions of some landscapes, rooms, interiors, patients cannot describe them with sufficient accuracy, are not able to decide whether they are seeing these pictures for the first time or whether they have an analogue in the real world. In general, visual hallucinations are most often vague, unclear, and indefinite.

In order to take the study of the right hemisphere seriously, it was necessary to step over the psychological barrier, to overcome the idea that it is a complete slacker. The reality exceeded all expectations. As a result, the right hemisphere was rehabilitated and equalized in rights with its left brother.

Yes, the right hemisphere does not possess many of the most important purely human functions. Yes, the right hemisphere is mute! But how expressively it can remain silent! What liveliness, brightness and persuasiveness he can impart to the speeches of his leftist brother! How musical, rich in sounds, poetic and colorful his world is! And it makes no sense to ask which hemisphere of the brain is more important for us. A bolt and a nut can only be useful if they work together. Alone they are helpless. Separately, they make little sense.

9.1. Violation of perceptual functions with damage to the left and right hemispheres of the brain and with damage to the median structures

In the above-mentioned examination of children aged 6-16 years old, conducted by E. G. Simernitskaya (see Chapter 8), along with an analysis of speech disorders in the same children, a study was carried out of the state of perceptual processes with lesions of the left and right hemispheres of the brain and with lesions of the median structures.

It has been shown that with damage to the left hemisphere, the most pronounced disturbances of visual gnosis are observed during the perception of crossed out and superimposed images (Poppelreiter figures). Lesions of the right hemisphere were accompanied by equally pronounced difficulties in visual perception of realistic images and Poppelreiter figures. Damage to the midline structures (diencephalic-hypothalamic region) led to greater difficulties in perceiving realistic images.

9.1.1. Impairment of perceptual functions due to damage to the left hemisphere of the brain

Visual disturbances with damage to the left hemisphere have a low frequency.

The maximum frequency of violations (in 29% of cases) was observed during the recognition of object images and was associated with damage to the occipital region of the left hemisphere.

These violations arose when it was necessary to identify and correlate several leading features of an object. The children did not rely on the entire set of features when perceiving the image; they singled out one and made guesses based on it. For example, a telephone was recognized as a clock, a table lamp as a mushroom.

The most pronounced violations of objective visual gnosis occurred during the perception of crossed out and superimposed images. They manifested themselves in difficulties in identifying a figure from the background, as a result of which only individual elements of the image were correctly assessed. For example, a hammer was recognized as a stick, a lily of the valley - twigs and leaves, a butterfly - a bat.

In visual-constructive activity (making drawings), mild disturbances were also observed. In young children they were not detected at all, even with damage to the parietal region. With age (after 10 years), the severity of pattern disturbances became increasingly higher.

In older children, the drawings were primitive and simplified. Spatial errors were also recorded when drawing three-dimensional figures.

With damage to the left hemisphere, the characteristic feature was the preservation of a graphic image, which was usually reproduced correctly.

In general, pattern disturbances were more often observed with lesions in the parietal region.

In children of senior school age with damage to the left hemisphere, disturbances in visual-spatial functions were observed (in tests of spatial praxis, copying with reversal, in tests of a clock and a map, etc.).

However, the frequency of their occurrence was low and when they were detected, the nature of these disorders corresponded to those disorders that occur in adults. These disorders, as in adults, were associated with projective or coordinate representations.

It can be assumed that the low frequency of manifestations of disturbances in the perceptual sphere with damage to the left hemisphere is of the same nature as the low frequency of speech disorders. The left-hemisphere components of perceptual activity, which are associated with speech mediation of perceptual processes, are not yet sufficiently formed, which is due to the ongoing formation of the speech system.

9.1.2. Impairment of perceptual functions due to damage to the right hemisphere of the brain

Early lesions of the right hemisphere, which appeared in the first year of life, lead to gross underdevelopment of those functions for which the right hemisphere is dominant (visuospatial perception, visual-constructive and other types of perceptual activity).

When the right hemisphere is damaged in children, disturbances in perceptual processes appear, as a rule, selectively. Often they arise only in the sphere of facial gnosis. Patients do not recognize their own

5-58 relatives, and in less severe cases they complain of poor memory for faces. Just as in adults, these disorders arose with damage to the right occipital region.

As with lesions of the left hemisphere, children with lesions of the right hemisphere showed a violation of object gnosis, but it was of a different nature. In this case, the errors were of the opposite nature: the mushroom was recognized as a table lamp, the clock as a telephone. This indicates the different nature of these violations. When the left hemisphere is damaged, due to a deficiency in the process of sequential analysis of all the features of an object, the details of the picture, it is typical to ignore individual elements of the image - a telephone handset, wires. In the case of damage to the right hemisphere, difficulties in perceiving the perceived object are compensated by analyzing possible options for the image (what could it be?) and, based on a guess, the object is, as it were, supplemented with “missing details.” Therefore, when the right hemisphere is damaged, the errors are very diverse: for example, a ball is recognized as a tomato, an omelette, a watermelon, etc., a coat is recognized as a house without a window, a glass is recognized as a washing machine.

Violations of subject gnosis with damage to the right hemisphere occurred more often than with damage to the left hemisphere.

The same disturbances were found in the perception of crossed out figures (Poppelreiter). But if, with damage to the left hemisphere, difficulties in this task were more pronounced (to a greater extent than when perceiving actually depicted objects), then with any damage to the right hemisphere there were no differences in the perception of figures when presented with each of these two tests. The errors were also of a different nature. With damage to the left hemisphere, each individual fragment of the image was perceived adequately, but its correlation with other features was disrupted, and this led to recognition based on an incomplete set of features. In the case of damage to the right hemisphere, on the contrary, difficulties in perceiving individual fragments were compensated by the emergence of side, random semantic connections that were not focused on the leading feature: jug - bread; butterfly - ribbon, pear, turnip, etc. This led to recognition focused on a redundant set of features that went beyond the image.

Thus, disturbances in object perception with damage to the right and left hemispheres were of a qualitatively different nature, due to the specific mechanisms of information processing in the left and right hemispheres - successive and simultaneous, respectively.

Lesions of the right hemisphere were also clearly manifested in the phenomenon of “left-sided inattention” - ignoring stimuli located in the left half of the visual field. This violation could manifest itself in the form of ignoring all stimuli located in the left half of the visual field; in other cases, the complete image disintegrated, and a conclusion about it was made on the basis of only signs located on the right. More often than not, only the extreme left elements were ignored.

Violations of color perception were recorded in isolated cases.

There were no impairments in animal recognition (in the presence of facial agnosia).

Disturbances in perceptual processes with damage to the right hemisphere were clearly manifested in the sphere of spatial representations, manifesting themselves in difficulties in spatial orientation.

In visual-constructive activity, when making drawings, disturbances were often in the nature of a gross defect, which was never observed with lesions of the left hemisphere.

This was most clearly evident when drawing three-dimensional figures. Often there was a disintegration of not only spatial representations, but also visual images in general.

A distinctive feature of right-hemisphere disorders (as opposed to left-hemisphere disorders) was that these disorders were not compensated for by copying.

Violation of the pattern occurred in 47% of cases and was maximally manifested in cases of damage to the right parietal region.

With damage to the right hemisphere, disturbances in topological ideas about an object occur (which does not happen with damage to the left hemisphere), as well as disturbances in ideas about the movement and transformation of an object.

At the same time, a comparison of disturbances in spatial representations in children and adults reveals some differences. They manifest themselves in the fact that in childhood the right hemisphere provides a wider range of spatial representations than in adults. For example, when the right hemisphere is damaged in children, both projective ideas and ideas about the coordinate system suffer (in adults, such disorders are observed only when the left hemisphere is damaged). In children, similar disorders occur equally with damage to both the left and right hemispheres.

In general, we can talk about the leading role of the right hemisphere in perceptual processes, which manifests itself already in childhood.

The absence of special differences in these disorders in children of primary and senior school age indicates that the dominance of the right hemisphere in perceptual processes occurs early.

9.1.3. Disturbance of perceptual processes with damage to the median structures

As noted above, damage to the hypothalamic-diencephalic region of the brain has traditionally been associated with a disruption of ascending activating influences, which led to changes in the normal functioning of the cortex.

Neuropsychological studies have shown that suffering in this area of ​​the brain leads not only to disturbances in the verbal non-sensical sphere (pathological inhibition of traces by interfering influences, which were described above), but also to disturbances in the perceptual sphere.

Violations of objective gnosis come to the forefront here, which appear especially clearly when perceiving realistic images. This is a qualitative difference between symptoms of disorders in this area from symptoms characteristic of damage to the left hemisphere (in this case, the perception of Poppelreiter figures suffers more than the perception of realistic images), and from symptoms of damage to the right hemisphere (in this case, the perception of realistic and schematic images suffers approximately equally ).

Just as with impaired auditory-verbal memory, perceptual impairments were more common with intracerebral lesions (in the region of the 3rd ventricle) than with extracerebral tumors.

The frequency and severity of disturbances in the perceptual sphere with damage to the hypothalamic-diencephalic region significantly exceed the same disturbances with damage to the left hemisphere and practically do not differ from right-hemispheric lesions.

Most often, these disorders occurred before the age of 10 years, and to a lesser extent after 10 years.

A distinctive feature of visual perception disorders was that they were most clearly manifested when perceiving images of “living” objects (in particular animals). In general, in childhood, impairments in the recognition of animal images are detected regardless of object and facial agnosia. This may indicate that these perceptions of these objects have different brain organizations.

For example, mistakes were typical when: a dog is recognized as a horse or a cow; hare - like a kitten, cat; chicken is like fish; a frog is like an owl. Such errors are extremely rare in hemispheric disorders, as a rule, only in cases where the pathological process in the hemispheres also affected the median structures.

Another important symptom is a violation of color gnosis (17.7% of cases).

Often coloring does not make it easier, but rather complicates the process of identifying an object. For example, orange is recognized as watermelon, cabbage; green watermelon - like orange, tomato.

Presenting colors outside the object increases the difficulty of their identification. The largest number of errors was in the perception of green, which was perceived as red, brown, yellow, gray, black. There were many errors in the perception of red, pink, and orange colors.

A characteristic feature was that errors could vary both among different patients and within one patient upon repeated presentation of stimuli.

Violation of color gnosis was detected mainly when naming colors, while the choice of a given color was available. When classifying color objects, errors occurred in distinguishing between red and green stimuli and attempts to place them in one group.

As E. G. Simernitskaya notes, the identified violations of color gnosis do not fit into the picture of congenital color anomalies, which are accompanied by a certain type of error. The variability of errors, the absence of color aphasia, and the isolated manifestation of this disorder indicate that the disturbance of color perception in children with damage to the midline structures has a different structure than that described in adults with damage to the left or right hemisphere.

In its manifestations, this disorder is most similar to the symptom of “anomia”, which is part of the “split brain” syndrome, when interhemispheric interaction between the structures that perceive visual information and which provide its verbal designation is disrupted. This usually occurs when the posterior parts of the corpus callosum are cut or damaged, that is, when interhemispheric connections are disrupted. But damage to the hypothalamic-diencephalic region does not lead to disorders of the corpus callosum. Only the anterior commissure is adjacent to this area, which plays an important role in interhemispheric transfer in animals.

It can be assumed that in the early stages of ontogenesis it is the anterior commissure that performs the function of such transfer. E. G. Simernitskaya (1985) gives examples that may testify in favor of this hypothesis.

In the first case, patient S., 12 years old, was operated on for a tumor of the third ventricle affecting the optic nerves and chiasm. He had a sharp decrease in vision in the left eye, as well as bitemporal hemianopsia. This led to the fact that perception remained intact only from the left half of the visual field in the right eye, from where information is transmitted, respectively, to the right hemisphere. Scheme of disturbances in the processing of visual information resulting from organic brain damage in patient S.

N. N. Bragina, T. A. Dobrokhotova

Syndromes and their clinical characteristics

PAROXYSMAL
The main symptom is paroxysmal occurrence. These states arise suddenly and quickly end.

Right hemisphere

Hallucinatory
False perceptions of something that is not in reality. Visual, tactile, auditory, olfactory, and taste hallucinations are possible. Auditory is expressed in imaginary rhythmic sounds - musical melodies, natural noises - birdsong, the sound of the surf. Olfactory and gustatory hallucinations, which usually occur when the deep parts of the temporal lobe of the right hemisphere are damaged, are unpleasant and painful in nature.

Derealization
The perception of the surrounding world is changed, devoid of reality. Patients may experience various sensations of this change: a different coloring of the world than it actually is; greater brightness of light than usual from past experience; distortions of spatial outlines, contours, sizes, shapes of objects (sometimes different in size, architectural design of houses and other buildings appear similar, not different from each other). An extreme version of derealization can be considered a feeling of immobility, deadness, soundlessness of the world, when everything moving (including surrounding people) is perceived by the patient as immobilized.

Symptom of “already seen”
An instantaneous feeling that the unfolding real situation is “already experienced,” “already seen,” “already heard,” although a similar situation did not exist in past memories.

"Never Seen"
The feeling is the opposite of the previous one. A situation that is well known, seen and experienced many times is perceived by the patient as “unfamiliar”, “never seen”, alien.

"Time Stop"
Instant feeling that time has “stopped”. This feeling is usually combined with an extreme version of the manifestation of derealization. Colors in the patient's perception become dull; three-dimensional, three-dimensional objects - flat, two-dimensional. At the same time, the patient perceives himself as having lost contact with the outside world and the people around him.

"Time Stretch"
In the patient’s sensations, time is experienced as “stretching”, longer than he is accustomed to from past experience. This sensation is sometimes combined with opposite (compared to the previous phenomenon) changes in the perception of the whole world. What is flat and two-dimensional appears to be three-dimensional, “alive, moving,” and gray-white is colored. The patient usually becomes relaxed, complacent or euphoric.

"Losing the sense of time"
A feeling revealed to patients in other expressions: “as if there was no time,” “freed from the oppression of time.” This is always accompanied by a changed perception of the whole world. Objects and people seem more contrasting and, in the emotional perception of patients, “more pleasant.”

"Time Slow"
Feeling like time is “moving more slowly.” The perception of the whole world, the movements of people and objects changes. People appear to be “puppet-like, lifeless,” their speech is “official.” Patients call time “slow” on the basis that people’s movements are perceived as slow and their faces are perceived as “sullen.”

"Time Acceleration"
The feeling is the opposite of the previous one. To the patient, time seems to flow more quickly than he was accustomed to from past perceptions. In the patient’s perception, the entire surrounding world and his own “I” are perceived as changed. The world seems “unnatural”, “unreal”, people are perceived as “fussy”, moving very quickly. They feel their body worse than usual. The time of day and duration of events are determined with errors.

"Reverse Flow of Time"
A feeling that is specified by patients in the following expressions: “time is flowing downwards”, “time is going backwards”, “I am going back in time”. The surrounding world and the patient’s own “I” are perceived as changed. The gross fallacy of reproducing the remoteness of already experienced events is interesting; a second or a minute ago events that took place are perceived as having happened “a long time ago”

Palinopsia
Also referred to as “visual perseveration”. This phenomenon is close to the previous one. The situation, which is already absent in reality, seems to linger in the patient’s field of vision. In patients, this phenomenon can be combined with impairment of the left visual field, decrease or loss of topographic memory.

Depersonalization
Within the framework of depersonalization syndrome, various options for an altered perception of one’s own “I” are described. The somatic or mental self may be perceived as altered; combinations of both are possible.

Somatic depersonalization
Occurs more often. It is expressed in an experience or sensation of one’s own body or its various parts that is different from what the patient is accustomed to from past perceptions. The whole body feels worse or only the left parts of it. At maximum severity, the patient ignores (not perceives) the left parts of the body, often the arm; the patient does not use his left hand, even if the weakness in it is insignificant. Sometimes the feeling of body integrity is disrupted; it (or its individual parts) “increases” or “decreases.” A feeling of multiplicity is possible, for example, the patient imagines that he has not one (left) hand, but several hands; at the same time, the patient often turns out to be unable to distinguish among them his own - the one that actually exists.

Mental depersonalization
It is expressed in a changed experience of one’s “I”, one’s personality, relationships with others, emotional contact with people. Patients say that they lose their senses, lose contact with all the people around them, using the phrase: “I go into another space, but everything remains in this space”, “I become an outside observer”, without “any feelings” I look at what “happens in this space.”

Total depersonalization
It includes changes in the perception of both the somatic and mental “I”, which seem to be regained when the patient recovers from the attack. The simultaneous occurrence of sensations of “foreignness” of one’s own voice, “physical splitting of the body into the smallest particles”, splitting of the mental “I” are described: “all parts of the body exist at this time as if independently and have their own “I”, in addition to the common “I”.

Two-track experience
A condition when the patient continues to perceive the surrounding reality; sometimes only what is on the patient’s right is perceived. In this case, a second stream of experiences arises in the form of involuntary revival, as if replaying in the consciousness of a specific period of time. In his consciousness, the patient is given, as it were, simultaneously in two worlds: in the real now world and in the world that was in the patient’s past tense. The patient identifies himself in consciousness, on the one hand, with how he is now and here (in present time and space), and on the other hand, as he was in a specific period of past time.

"Flash of Experience"
A state in which the patient ceases to perceive what exists in reality (in the objective present time and real space) and in his consciousness, as it were, returns entirely to some segment of the past time. In the patient’s consciousness, all the events that happened in that past are played out again, and they are experienced by the patient in the true sequence. The patient perceives himself as he was in that period of past time.
Oneiroid
This refers to a short-term transient oneiric state. The patient ceases to perceive himself and the world around him as they are in objective time and space. In the consciousness of the patient, he experiences a seemingly different, unreal world, more often a world of fantastic events (flights into space, meetings with aliens). In the retrospective (after recovery from the attack) description of the patient, the other world looks devoid of spatio-temporal supports. At the moment of experiencing oneiroid, the patient often experiences a feeling of weightlessness. It is close to “gravitational illusions,” described as the subjective experience of changes in the weight of one’s own body, which is explained by the activation in the cerebral cortex of those engrams that capture the acquired experience of subjective sensations during short-term changes in the weight of the body.

Emotional and Affective Disturbance Syndrome
There are three possible violations:
a) attacks of melancholy, fear or horror (with temporal localization of the lesion), combined with viscero-vegetative disorders, olfactory and gustatory hallucinations;
b) euphoria with relaxation (with damage to the parieto-occipital regions);
c) a state of unemotionality - a transient interruption of affective tone (with temporo-parietal-occipital lesions), often combined with the phenomena of derealization and depersonalization.

Left hemisphere

Hallucinatory
The most common are auditory and verbal hallucinations. Patients hear voices calling them by name or telling them something. Hallucinations can be multiple: the patient hears many voices at once, but cannot make out the content of what these voices are saying.

Speech disorder syndromes
Transient (motor, sensory, amnestic) aphasias that come on suddenly and quickly end. Such transient speech disturbances at the time of an attack occur in patients more often at a time when no changes in speech are observed outside the paroxysms.

Thinking disorders
More often, two conditions that are opposite to each other occur:
a) “thought gaps” - a feeling of emptiness in the head, as if “the formation of thoughts has stopped”; outwardly at the time of the attack, the patient looks anxious, confused, with an expression of bewilderment on his face;
b) “violent thoughts”, “surges of thoughts”, “whirlwind of thoughts” - a feeling of sudden appearance in the mind of thoughts that are not related in content to current mental activity; sometimes quickly, “like lightning,” a lot of thoughts appear, “interfering with each other,” “these thoughts make your head swell”; not a single thought is completed, has no complete content; these thoughts are experienced with a tinge of burdensomeness, violence, involuntaryity - the impossibility of freeing oneself from them until the attack is over.

Memory disorders
There are two extreme options:
a) “memory failure” – helplessness, inability to remember the right words, names of loved ones, even one’s age, place of work, accompanied by confusion and anxiety;
b) “forced memory” - a painfully painful feeling of the need to remember something, but at the same time the awareness of what exactly is being remembered remains unattainable; This inaccessibility of awareness of the subject of the memory is combined with an anxious feeling, the fear that something “is about to happen” to the patient.

Absence
Turning off the patient from conscious mental activity in which he was engaged before the attack. The position in which the patient experienced the attack is preserved. All signs of attention in the patient’s appearance disappear; the gaze becomes motionless, the face becomes “stony”. It lasts a moment and the interlocutor can take a forced, natural pose. The patient himself does not remember what happened; An absence seizure usually results in complete amnesia. For a long time, attacks may go unnoticed by the patient and those around him. They become obvious as they become more complex due to the addition of speech and other phenomena.

Psychomotor seizures
Lasts minutes, hours, rarely – several days. While falling into an attack, the patient continues to be active. Performs a variety of actions, sometimes complex and consistent psychomotor activity. These seizures differ from twilight states of consciousness in their lack of purposefulness and less sequence of actions: patients rush to run somewhere, begin to move extremely heavy objects from their place. Actions and actions are accompanied by shouts, usually meaningless. The patient's behavior becomes orderly only upon recovery from an attack, which is followed by amnesia.

Twilight consciousness disorder
A sudden onset and suddenly ending state of altered consciousness, which is characterized by the implementation of complex sequential psychomotor activity, ending with a socially significant result, as well as amnesia for an attack. Conventionally, two options can be distinguished:
a) being in a twilight state of consciousness, patients continue to implement the program that was in consciousness before the onset of this state;
b) falling into a twilight state of consciousness, patients commit actions and deeds that were never in their intentions, alien to their personal attitudes; these actions are determined by psychopathological experiences - hallucinatory, delusional, which arise along with the onset of an altered state of consciousness. The first option coincides with a condition known as ambulatory automatism. With the second option, malice, irritation, anger, and aggressiveness are possible.

Syndrome of emotional, affective disorders
Many of the paroxysmal states listed above (transient aphasia, violent thoughts and memories, etc.), as a rule, are accompanied by an affect of anxiety and confusion. Independent paroxysms are possible, during which patients experience an affect of anxiety; At this point they become fussy, restless, and impatient. They express fears: “something is going to happen to me.” These concerns are always directed towards the future.

NON-PAROXYSMAL

Right hemisphere

Confabulatory confusion
A disturbance of consciousness in which the patient is disoriented in space and time so that the present reality is perceived as if through the content of past time. This is expressed in abundant confabulations: as events that just happened (in the hospital), the patient names events that happened sometime in the past and in some other place (at work, at home, etc.). Patients do not remember anything that happens and may be restless motorly. The words “here” and “now” are meaningless for them.

Korsakov's syndrome
The syndrome necessarily includes disorientation in space and time. Sometimes the patient is disoriented regarding his own personality; amnesia – fixation, retroanterograde; confabulation (in response to a question, for example, about what the patient did in the morning, he can name events that took place many years ago); false recognitions (in the surrounding faces the patient “recognizes” the faces of his loved ones and calls them by the names of these people); emotional and personal changes (patients are relaxed, complacent or even euphoric, verbose, exhibit anosognosia and, while the complete helplessness of the patients is obvious to everyone around them, they consider themselves healthy); disorders of the perception of space and time (for example, in the morning, patients can say that it is already evening; they err on the side of prolongation in determining the duration of events). Korsakoff's syndrome is often associated with left-sided hemiparesis, hemianesthesia, hemianopsia, and left space neglect.

Left-sided spatial agnosia
It is characterized by a cessation of perception (ignoring) of events that occur to the left of the patient. All stimuli are ignored by the patient: visual, auditory, tactile. Patients feel their body poorly or do not perceive it at all, most often this applies to the left parts, especially the left arm. They ignore the left side of the text when reading, the left side of the paper when drawing, etc. Patients are euphoric and relaxed; anosognosia is detected.

sad depression
Characterized by melancholy, motor and ideational retardation. This triad of symptoms usually occurs when the temporal part of the right hemisphere is damaged. The patient is inactive, speaks quietly, slowly; the face froze in one position.

Pseudological
Patients tend to mention or even describe in detail events that happened to them that did not actually take place. As a rule, patients do not derive any benefit from such pseudological statements. Patients are usually talkative and complacent, quickly coming into contact with people around them.

Emotional and personal changes
The most common and pronounced tendency is towards the predominance of a complacent or euphoric mood, inadequate to the patient’s condition and its severity. Criticism is decreasing. Often, lack of awareness and denial of one’s illness and painful condition is anosognosia. Sometimes euphoria is combined to a pronounced degree with motor activity to the point of disinhibition; patients are cheerful, talkative, mobile, although they may exhibit left-sided hemiplegia, blindness and other signs of deep incompetence.

Sleep and dream disorders
Frequent indications from patients about an increase in the number of dreams: “I feel like I’ve been dreaming all night.” Sometimes colored dreams are noted. Patients often note that it is difficult for them to distinguish what happened in a dream from what happened in reality. Some patients experience stereotypical repetitions of the same dream.

Recurrent psychosis
Reminiscent of MDP, where conditions reminiscent of hypomania and depression are periodically repeated. They are distinguished by greater expression not of the emotional component itself, but by greater activity; in “good” condition, patients are highly active, productive, and sleep little; in “bad” conditions – lethargic, drowsy, tired.

Left hemisphere

Dysmnestic
At the center of the syndrome is a weakening of verbal memory. The patient forgets words, names, phone numbers, actions, intentions, etc. Forgetting does not reach the point of impossibility of reproducing the necessary information. The patient has an understanding of the defect and an active desire for compensation. They keep notebooks and write down everything that needs to be remembered.

Anxious depression
Characterized by anxiety and motor restlessness, confusion. Patients seem to be in a continuous search for motor rest; change position, stand up, sit down and get up again. They sigh, look around in bewilderment, and peer into the face of their interlocutor. They express fears that something is going to happen to them.

Delusional syndrome
At the center of the syndrome is a disorder of thinking with errors of judgment that cannot be corrected. Patients become more and more suspicious, distrustful, and anxious. They suspect others of having an unkind attitude towards them, of an intention to cause harm (to poison, disfigure, or have a bad influence on them). Externally the patient is tense. Sometimes he refuses food and medicine.

Speech changes
Even before the onset of aphasia, there may be speech aspontaneity with a lack of motivation for speech activity, or slips of the tongue may become increasingly common, when patients replace one word with another and do not notice it themselves. Speech becomes less and less detailed and monosyllabic.

Sleep and dream disorders
There is a decrease in dreams. Sometimes patients note the disappearance of dreams as one of the signs of changes in their sleep and dreams.

Emotional and personality changes
With damage to the frontal regions, patients are less and less proactive and aspontaneous; temporal - more and more anxious, tense, confused; There appears to be an increase in the vigilance of the patients, they are constantly mobilized. When the posterior parts of the left hemisphere are affected, a painful tone usually predominates in the mood of patients.

TABLE OF SYNDROMES ARISING DURING SELECTIVE
LESIONS TO THE RIGHT AND LEFT HEMISPHERES OF THE BRAIN (IN RIGHT-HANDED PEOPLE)

© N. N. Bragina, T. A. Dobrokhotova

Syndromes of damage to the right (subdominant) hemisphere have not yet been sufficiently studied. Method of cutting the corpus callosum (when cutting the corpus callosum and applying stimuli to the right hemisphere, naming objects is impossible, the ability to directly perceive objects and diffusely distinguish the meaning of words is preserved): Sperry confirmed that any HMF is carried out by the joint work of both hemispheres, each of which contributes one’s own contribution to the construction of mental processes.

The right hemisphere has nothing to do with speech activity, and its lesions, even quite extensive ones, do not affect speech processes. The subdominant hemisphere is less involved in providing complex intellectual functions and providing complex forms of motor acts. (right-handers with damage to the right hemisphere do not show pronounced impairments in active speech, writing (logical thinking, understanding of logical-grammatical constructions, formal logical operations, counting is also preserved), reading, even in cases where these lesions are located within the temporal, parieto-occipital, premotor zones, which in case of damage to the left hemisphere causes aphasia. The right hemisphere has less functional differentiation of cortical structures compared to the left: disturbances of the cutaneous and deep sensitivity of the right hand are caused by lesions of the postcentral parts of the left hemisphere, then the same disturbances of cutaneous and kinesthetic sensitivity in the left hand. may occur with significantly more diffuse lesions of the cortex of the subdominant hemisphere. Hulings Jackson (1874): the right hemisphere is directly related to perceptual processes and is an apparatus that provides more direct, visual forms of relations with the outside world. The right hemisphere is related to the analysis of the information that. the subject receives from his own body and which is not associated with verbal-logical codes. The role of the right hemisphere in immediate consciousness.

*superior parietal syndrome secondary areas - disturbances of the body diagram (left side)– somatoagnosia-impaired recognition of one’s own body parts and their tactile location to each other

*damage to the middle parietals - unilateral spatial agnosia– ignoring the left side of the body.

*damage to the posterior deep parts of the right p – left-sided fixed hemianopsia(violation of visual fields).

* Apraxia of dressing– disturbances in the sensations of your body, parts seem either very large or disproportionately small.

*Constructive agnosia and apraxia (TPO-inability to assemble into a single whole) are gnostic disorders. “Simultaneous agnosia” (Balint’s syndrome) – parieto-occipital regions. The patient correctly perceives only one image, since the volume of perception is narrowed, he cannot perceive the whole, only parts. + gaze ataxia - erratic, inconsistent eye movements.

*Impaired recognition of objects with damage to the posterior parts of the right hemisphere, loss of the sense of their familiarity. – facial agnosia– do not recognize relatives. + paragnosis - uncontrolled guessing when assessing an object.

The functions of the right hemisphere include the general perception of one’s personality - anosognosia– do not notice them, are not critical of their own defects.

*profound changes in personality and consciousness - the perception of the situation as a whole becomes defective since there are no signals from the body, the phenomenon of disorientation in the surrounding world, time, confusion of immediate consciousness, verbosity and reasoning (since verbal-logical processes are preserved).