Research of cognitive functions

In the clinical practice of a neurologist, the evaluation of cognitive functions includes the study of orientation, attention, memory, counting, speech, writing, reading, praxis, gnosis.

Orientation

The study of the patient's ability to orient himself in his own personality, place, time and current situation is carried out in parallel with an assessment of the state of his consciousness.

• Self-orientation: ask the patient to give their name, address, profession, marital status.
• Orientation in place: ask the patient to say where he is now (city, name of medical facility, floor) and how he arrived here (by transport, on foot).
• Orientation in time: ask the patient to name the current date (day, month, year), day of the week, time. You can ask the date of the nearest approaching or past holiday.

Further investigation of the patient's mental functions is carried out if it is determined that he is in a clear consciousness and is able to understand the instructions and the questions asked to him.

Attention

By human attention is understood as the ability to comprehend many aspects of stimulating effects at any point in time, and the nonspecific factor of ensuring selectivity, the selectivity of the course of all mental processes in general. Neurologists often denote this term the ability to focus on certain sensory stimuli, distinguishing them from among others. It is accepted to distinguish between fixing attention, switching attention from one stimulus to another, and maintaining attention (necessary to complete a task without signs of fatigue). These processes can be arbitrary and involuntary.

The ability to concentrate and hold attention is roughly violated in states of acute confusion, less affected by dementia and, as a rule, not disturbed by focal lesions of the brain. Concentration of attention is checked by asking the patient to repeat a series of figures or for some time to delete a certain letter that is written on a sheet of paper in a random alternation with other letters (the so-called proof-reading test). Normally, the examinee correctly repeats 5-7 digits for the researcher and erases the desired letter without errors. In addition, to assess the attention, you can offer the patient to count up to ten in direct and reverse order; list days of the week, months of the year in direct and reverse order; arrange the letters that make up the word "fish" in alphabetical order or pronounce the word by the sounds in reverse order; To inform, when among the named in random order sounds meets required, etc.

See also:  Syndrome of diffused attention

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Memory

The term " memory " refers to the process of cognitive activity, in which three components are distinguished: the acquisition and coding (memorization) of information; its storage (retention, retention) and playback (extraction).

In accordance with the concept of temporary organization of memory, its following types are distinguished: immediate (instantaneous, sensory), short-term (working) and long-term.

• Tests evaluating immediate memory are similar to samples for assessing attention and include the patient's immediate reproduction of a series of numbers or words that the subject previously did not memorize. For example, ask him to repeat the following series of figures after the doctor (they should be pronounced slowly and clearly): 4-7-9, 5-8-2-1, 9-2-6-8-3, 7-5-1- 9-4-6, 1-8-5-9-3-6-7, 9-3-8-2-5-1-4-7. Then they propose to repeat a series of figures, naming them in the order opposite to the one in which they were called earlier. Normally, a healthy adult with average intelligence can easily reproduce a series of seven digits in a straight sequence and five digits in the reverse order. In addition, you can offer the patient to name three subjects that are not logically related to each other (for example, "table-road-lamp"), and ask them to repeat these words immediately.
• To assess short-term memory, the patient's ability to learn new material and recall newly learned information is examined. Verify verbal and nonverbal (visual) memory using the following tests.
  • Ask the examinee to list what he ate for breakfast.
  • Call the patient his name and patronymic (if he did not know them before) and after a while ask him to repeat.
  • Call the patient three simple words (for example, denoting the name, time of day, a piece of clothing) and immediately ask to repeat them. If the patient made a mistake, the attempts are repeated until he calls all three words correctly (the number of attempts is recorded). After 3 minutes, the subject is asked to recall these three words.
  • Invite the patient to remember the sentence. Slowly and clearly read the phrase out loud and ask the patient to repeat it. If he made a mistake, the attempts are repeated until the patient is able to cope with the task. The number of attempts is recorded. You can also suggest that the patient reproduce the short phrases added by the doctor (the patient repeats them aloud, starting with the first, then the second and subsequent ones, for example: "One special original," "Two good wild porcupines," "Three thick quiet tarantulas," "Four turtles they scratched the skull of an eccentric person "," Five quails were pleasantly sung, having dined well. "If the patient accurately repeated the first four phrases, then one can consider memory to be good.
  • They show the patient a drawing on which several objects are depicted, and ask them to remember them; then, removing the figure, they propose to list these objects and note the number of errors. You can also display a drawing depicting a number of objects, and then ask the examinee to find these objects in a different set of images.
• Long-term memory is evaluated by asking the patient about autobiographical, historical, cultural events (specific questions depend on the expected level of his education). For example, you can invite him to name the date and place of his birth; place of study; the name of the first teacher; date of marriage / marriage; the names of parents, spouse, children and the date of their birthdays; the name of the country's president; well-known historical dates (the beginning and the end of the Great Patriotic War); names of major rivers and cities in Russia.

Read also:  Memory malfunction

Score

The violation of the counting and counting operations, which occurs in patients with organic brain damage, is designated by the term "acalculia". Primary (specific) acalculia occurs in the absence of other disorders of higher cerebral functions and is manifested by a violation of ideas about the number, its internal composition and discharge structure. Secondary (nonspecific) acalculia is associated with primary disorders of recognition of words denoting numbers and figures, or with disrupted development of an action program.

Assessment of the account in clinical neurological practice is most often limited to tasks for performing arithmetic operations and solving simple arithmetic problems.

• Serial account: ask the patient to perform a serial subtraction of seven out of 100 (subtract seven out of 100, then consecutively subtract seven from the remainder 3-5 more times) or three of 30. Mark the number of errors and the time that the patient needs to complete the task. Errors in the test can be observed not only in acalculia, but also in disorders of concentration of attention, as well as in apathy or depression.
• If the patient has violations of cognitive functions in solving these problems, he is offered simple problems of addition, subtraction, multiplication, division. You can offer a solution for everyday tasks with arithmetic actions: for example, to calculate how much you can buy pears for 10 rubles, if one pear costs 3 rubles, how many will remain with the change, etc.

Ability to generalize and abstract

Ability to compare, generalize, abstract, form judgments, and planning refers to the so-called "executive" mental functions of a person connected with arbitrary regulation of all other spheres of mental activity and behavior. Various violations of executive functions (for example, impulsivity, limited abstract thinking, etc.) in a mild form are possible in healthy individuals, so the main significance in diagnosis is attached not to determining the type of executive function disorders, but to assessing their severity. In neurological practice, only the simplest tests are used to evaluate executive functions. When examining, it is important to obtain information about the premorbid features of the patient. The patient is offered to explain the meaning of several well-known metaphors and sayings ("golden hands", "do not spit into a well", "go quietly - you will continue", "wolf appetite", "a bee for a tribute to the field flies from a wax cell", etc.). ), to find similarities and differences between objects (apple and orange, horse and dog, river and canal, etc.).

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Speech

When talking to a patient, they analyze how he understands the speech addressed to him (the sensory part of speech) and reproduces it (the motor part of speech). Speech disorders are one of the most difficult problems of clinical neurology, it is examined not only by neurologists, but also by neuropsychologists, speech therapists. Below we consider only the main issues of speech disorders that help topical diagnosis.

Speech may suffer relatively isolated from other higher cerebral functions in focal lesions of the brain or simultaneously with other disorders in the cognitive sphere in dementias. Aphasia is a violation of an already formed speech that occurs with focal lesions of the cortex and the adjacent subcortical region of the dominant hemisphere (left in right-handed hemispheres) and represents a systemic disorder of various forms of speech activity with the preservation of the elementary forms of hearing and movements of the speech apparatus (that is, without the paresis of the speech musculature - lingual, laryngeal, respiratory muscles).

Classical motor aphasia (Broca's aphasia) occurs when the posterior sections of the inferior frontal gyrus of the dominant hemisphere are affected, and sensory aphasia (aphasia Wernicke) occurs when the middle and posterior sections of the upper temporal gyrus of the dominant hemisphere are affected. With motor aphasia, all kinds of oral speech are violated (spontaneous speech, repetition, automated speech), and also a letter, but the understanding of oral and written speech is relatively safe. With sensory aphasia, Wernicke suffers both an understanding of oral and written speech, and his own oral and written speech of the patient.

In neurological practice, speech disorders are diagnosed when assessing spontaneous and automated speech, repetition, naming objects, understanding speech, reading and writing. These studies are performed in patients with speech disorders. When examining a patient it is important to determine the dominance of his hemispheres, that is, to find out whether he is right-handed or left-handed. Here it can be mentioned that, according to neurophysiologists, the left hemisphere provides functions of abstract thinking, speech, logical and analytical functions mediated by the word. People who have the predominant functions of the left hemisphere (right-handed people) gravitate toward theory, are purposeful, are able to predict events, are active in the motor. In patients with functional dominance of the right hemisphere of the brain (left-handed), specific thinking prevails, slowness and taciturnity, a tendency to contemplation and memories, emotional coloring of speech, musical ear. To clarify the dominance of the hemisphere, the following tests are used: determination of the dominant eye with binocular vision, folding of the hands in the lock, determination of the force of compression into the fist by a dynamometer, folding of hands on the chest ("Napoleon's pose"), applause, jogging, etc. Right- , the thumb of the right hand when folding the hands into the lock is on top, the right hand is stronger, it is more active when applauding, when folding the hands on the chest, the right forearm, right leg of the tremors aya, and left-handers all the way around. Often observe the convergence of the functional capabilities of the right and left hands (ambidextria).

• Spontaneous speech begins to explore when you meet a patient, asking him questions: "What's your name?", "Who do you work for?", "What bothers you?", Etc. It is necessary to pay attention to the following disorders.
  • Changes in the speed and rhythm of speech, which is manifested in slowing, intermittent speech, or, conversely, in its acceleration and stopping difficulties.
  • Violations of melodic speech (disprosodiya): it can be monotonous, inexpressive or acquires a "pseudo-foreign" accent.
  • Suppression of speech (complete absence of speech production and attempts to voice communication).
  • The presence of automatisms ("verbal emboli") - often, involuntarily and inadequately used simple words or expressions (exclamations, greetings, names, etc.), most resistant to elimination.
• Perseverations ("stuck", repetition of the already pronounced syllable or word that occurs when trying to communicate verbally).
• Difficulties in choosing words when naming objects. The patient's speech is indecisive, rife with pauses, contains many descriptive phrases and words of a substitute nature (like "well, how is it there ...").
• Paraphasia, that is, mistakes in pronouncing words. They distinguish phonetic paraphasia (inadequate production of phonemes of the language due to simplification of articular movements: for example, instead of the word "shop" the patient is pronounced "zimin"); Lateral paraphasia (replacement of some sounds by others, similar in sound or place of origin, for example, "hummock" - "kidney"); verbal paraphasia (the replacement of one word in a sentence by another, reminiscent of it in meaning).
• Neologisms (linguistic formations used by patients as words, although there is no such word in the language on which he speaks).
• Agrammatisms and paragrammatisms. Agrammatism is a violation of grammar rules in the sentence. The words in the sentence do not agree with each other, the syntactic structures (auxiliary words, conjunctions, etc.) are reduced and simplified, but the general meaning of the transmitted message remains understandable. With paragrammatisms, words in the sentence are formally consistent, syntactic structures are sufficient, but the general meaning of the sentence does not reflect the actual interrelationships of things and events (for example, "Hay Drying Peasants in June"), as a result, it is impossible to understand the information transferred.
• Echolalia (spontaneous repetition of words pronounced by the doctor or their combinations).
• To evaluate an automated speech, the patient is offered to count from one to ten, list days of the week, months, etc.
  • To assess the ability to repeat speech, the patient is asked to repeat the vowel and consonant sounds ("a", "o", "u", "y", "b", "d", "k", "c" and etc.), oppositional phonemes (labial - b / n, front-language - t / d, s / s), words ("house", "window", "cat", "moan", "elephant", "colonel" "," Fan "," ladle "," shipwreck "," cooperative ", etc.), a series of words (" house, forest, oak, "" pencil, bread, tree "), phrases (" The girl is drinking tea ";" The boy is playing "), tongue twisters (" On the grass, on the grass, firewood ").
  • The ability to naming objects is assessed after the patient calls the objects displayed to him (clock, pen, tuning fork, flashlight, sheet of paper, body parts).
• To assess the understanding of oral speech, the following tests are used.
  • Understanding the meaning of words: name the object (hammer, window, door) and ask the patient to indicate it in the room or in the picture.
  • Understanding oral instructions: asking the patient to perform one, two, and three-part tasks sequentially ("Show me your left hand", "Lift your left hand and touch the right ear with your fingers", "Raise your left hand, touch your right hand with your fingers to the right ear, at the same time stick out the tongue "). Instructions should not be supported by facial expressions and gestures. Evaluate the correctness of the commands. If the examinee has difficulties, repeat the instructions, accompanying them with facial expressions and gestures.
  • Understanding of logical and grammatical structures: asking the patient to perform a number of instructions containing genitive case designs, comparative and reflexive verb forms or spatial adverbs and prepositions: for example, to show a pencil key in a pencil, a pencil key; put the book under the notebook, the notebook under the book; show which subject is more, and which is less light; to clarify who is spoken about in the expression "mother's daughter" and "daughter's mother", etc.
• To assess the function of the letter, ask the patient (having supplied him with a pen and a piece of paper) to write his name and address, then write down a few simple words ("cat", "house") at the dictation; the sentence ("The girl and the boy is playing with the dog") and write off the text from the sample printed on paper. In patients with aphasia, in most cases, the letter suffers (that is, there is an agraphy - the loss of the ability to write correctly while maintaining the motor function of the hand). If the patient can write, but does not speak, he is likely to have a mutism, but not aphasia. Mutism can develop in a variety of diseases: with severe spasticity, paralysis of the vocal cords, bilateral defeat of corticobulbar tracts, and also possible with mental illness (hysteria, schizophrenia ).
• To evaluate the reading, the patient is offered to read a paragraph from a book or newspaper, or read and execute an instruction written on paper (for example, "Go to the door, tap it three times, go back"), then assessing the correctness of its execution.

For neurological diagnostics, the ability to distinguish motor aphasia from dysarthria, which is characteristic for bilateral lesions of cortico-nuclear tracts or nuclei of cranial nerves of the bulbar group, is of great importance . With dysarthria, the patients say everything, but they pronounce the words poorly, the speech sounds "p", "l", and also hissing are especially difficult for articulation. Building sentences and vocabulary do not suffer. With motor aphasia, the construction of phrases and words is broken, but at the same time the articulation of certain articulate sounds is clear. Aphasia also differs from alalia - underdevelopment of all forms of speech activity, manifested by speech disturbance in childhood. The most important signs of various aphasic disorders are summarized below.

• With motor aphasia, patients generally understand someone else's speech, but find it difficult to choose words to express their thoughts and feelings. Their vocabulary is very poor, can be limited to just a few words ("embobble words"). When talking, patients make mistakes - literal and verbal paraphasia, try to correct them and are often angry with themselves for not being able to speak correctly.
• The main signs of sensory aphasia include difficulties in understanding someone else's speech and poor auditory control of one's own speech. Patients tolerate many literal and verbal paraphasia (sound and verbal errors), do not notice them and get angry with the interlocutor who does not understand them. With pronounced forms of sensory aphasia, patients are usually talkative, but their statements are obscure to others ("speech salad"). To identify sensory aphasia, you can use Marie's experience (the patient is given three sheets of paper and suggests that one of them be thrown on the floor, another put on the bed or table, and the third returned to the doctor) or Geda (the subject is offered to put a large coin in a small glass, in a large, experience can be complicated by putting four different glasses, as many different in size coins and inviting the patient to place them).
• With foci at the junction of the temporal, parietal and occipital lobe, one of the variants of sensory aphasia may occur, the so-called semantic aphasia, in which the patients do not understand the meaning of individual words, but the grammatical and semantic connections between them. Such patients can not, for example, distinguish the expressions "brother of the father" and "father of the brother" or "the cat ate the mouse" and "the cat is eaten by the mouse".
• Many authors distinguish one more type of aphasia - the amnestic, in which patients find it difficult to name the various objects displayed, forgetting their names, although they can use these terms in spontaneous speech. Usually, such patients help if they are told the first syllable of the word that denotes the name of the displayed object. Amnestic speech disorders are possible with different types of aphasias, but most often they occur with lesions of the temporal lobe or parieto-occipital division. Amnestic aphasia should be distinguished from a broader concept of amnesia, that is, a memory disorder in previously developed concepts and concepts.

Praxis

By praxis is understood the ability to perform successive complexes of conscious voluntary movements to perform purposeful actions on the plan worked out by individual practice. Apraxia is characterized by loss of skills developed in the course of individual experience, complex targeted actions (household, industrial, symbolic gestures, etc.) without pronounced signs of central paresis or movement coordination disorders. Depending on the localization of the lesion, several types of apraxia are distinguished.

• Motor (kinetic, efferent) apraxia is manifested in the fact that the successive switching of movements is disrupted and there are disturbances in the formation of motor links that create the basis of motor skills. Characterized by a disorder of smoothness of movements, "stuck" on separate fragments of movements and actions (motor perseverations). Observed at the focal point in the lower parts of the premotor region of the frontal lobe of the left (right-handed) hemisphere (with the lesion of the precentral gyrus, central paresis or paralysis develops, in which apraxia can not be detected). To identify motor apraxia, the patient is asked to perform a "fist-rib-palm" test, that is, tap the surface of the table with his fist, then with the edge of the palm, and then palm with the fingers straight. This series of movements is asked to be repeated at a fairly rapid pace. A patient with a lesion of the premotor region of the frontal lobe experiences difficulty in performing such a task (strayed from a sequence of movements, unable to perform a task at a rapid pace).
• The ideomotor (kinesthetic, afferent) apraxia occurs when the lower parietal lobe is affected in the region of the marginal gyrus, which is referred to the secondary fields of the cortex of the kinesthetic analyzer. In this case, the hand does not receive afferent feedback signals and is unable to perform subtle movements (at the same time, the focus in the primary fields of the postcentral gyrus causes a gross sensitivity disorder and afferent paresis, in which the ability to control the opposite arm is completely lost, but this apraxia disorder does not carry). Apraxia manifests itself as a violation of fine differentiated movements on the opposite side of the lesion: the hand can not accept the pose necessary to perform an arbitrary movement, adapt to the nature of the object to which the given manipulations are performed (the "hand-shovel" phenomenon). Characteristic search for the necessary posture and error, especially if there is no visual control. Kinesthetic apraxia is revealed when performing simple movements (both with real objects, and in simulating these actions). To detect it, the patient should be asked to stick out his tongue, whistle, show how the match is lit (pour water in a glass, use a hammer, hold a pen to write it, etc.), dial a phone number, and comb hair. You can also invite him to close his eyes; fold his fingers into some simple figure (for example, "goat"), then destroy this figure and ask yourself to restore it.
• Constructive apraxia (spatial apraxia, apractognosia) is manifested in violation of the coordination of joint movements of hands, difficulty in performing spatially oriented actions (it is difficult to make beds, get dressed, etc.). A clear difference between the performance of movements with open and closed eyes can not be traced. This type of disorder includes constructive apraxia, manifested in the difficulty of constructing the whole from individual elements. Spatial apraxia occurs when the focus is located in the joint zone of the parietal, temporal and occipital regions (in the zone of the angular convolution of the parietal lobe) of the left cortex (in righties) or both hemispheres of the brain. With the defeat of this zone, the synthesis of visual, vestibular and skin-kinesthetic information is disturbed and the analysis of the coordinates of action worsens. Tests that reveal constructive apraxia consist in copying geometric figures, in the image of the dial of a clock with the arrangement of numbers and arrows, in constructing structures from cubes. The patient is asked to draw a three-dimensional geometric figure (for example, a cube); to draw a geometric figure; Draw a circle and place the numbers in it as if on a clock face. If the patient has coped with the task, ask him to arrange the arrows so that they show a certain time (for example, "quarter to four").
• Regulatory ("prefrontal", ideatoric) apraxia includes violations of voluntary regulation of activities that directly affect the motor sphere. Regulatory apraxia manifests itself in the fact that the execution of complex movements is violated, including the execution of a series of simple actions, although each of them can individually perform a correct patient. The ability to imitate is also preserved (the patient can repeat the actions of the doctor). At the same time, the examinee is not able to draw up a plan of successive steps necessary to perform a complex action, and is not in a position to control its implementation. The greatest difficulty is simulating actions with missing objects. For example, a patient finds it difficult to show how sugar is mixed in a glass of tea, how to use a hammer, comb, etc., while all these automatic actions with real objects he performs correctly. Starting to perform the action, the patient switches to random operations, getting stuck on the fragments of the started activity. Characteristic of echopraxia, perseveration and stereotypy. Patients also are characterized by excessive impulsivity of reactions. Regulatory apraxia occurs when the prefrontal cortex is damaged in the frontal lobe of the dominant hemisphere. To identify it, patients are offered to get a match from the matchbox, light it, then put it out and put it back in the box; open a tube with toothpaste, squeeze out a paste on the toothbrush, screw the cap on the tube with paste.

Gnosis

Agnosia is a disorder of recognition of objects (objects, persons) with preservation of elementary forms of sensitivity, vision, hearing. There are several types of agnosia - visual, auditory, olfactory, etc. (depending on the type of analyzer within which the violation occurred). In clinical practice, optic-spatial agnosia and autopopnosion are most often observed.

• Optical-spatial agnosia is a violation of the ability to perceive spatial features of the environment and images of objects ("near-closer", "more-less", "left-right", "top-bottom") and the ability to navigate in the outer three-dimensional space. It develops when the upper or parietal-occipital parts of both hemispheres or the right hemisphere of the brain are affected. To identify this form of agnosia, the patient is offered to draw a map of the country (in the approximate version). If he can not do this, draw the map himself and ask him to mark the location of five large, badly known cities. You can also invite the patient to describe the path from home to the hospital. The phenomenon of ignoring one half of space (one-sided visual-spatial agnosia, one-sided spatial non-elect, hemimensional non-elect, hemispheric sensory inattention) is considered to be a manifestation of optic-spatial agnosia. This syndrome manifests itself in the difficulty of perceiving (ignoring) information coming from one hemisphere of the surrounding space, in the absence of a primary sensory or motor deficit in the patient, including hemianopsia. For example, the patient eats only the food that lies on the right side of the plate. The phenomenon of ignoring is associated mainly with the defeat of the parietal lobe, although it is also possible with temporal, frontal and subcortical localization of the pathological process. The most common phenomenon is the ignoring of the left half of space in the defeat of the right hemisphere of the brain. To identify the syndrome of ignoring, use the following tests (it must be emphasized that they are only applicable if the patient does not have hemianopsia).
  • The patient is given a notebook sheet "in line" and asked to divide each line in half. With the ignore syndrome, the right-hander will put the marks not in the middle of the lines, but at a distance of three quarters from the left edge (that is, halves only the right half of the lines, ignoring the left).
  • The patient is asked to read the paragraph from the book. If ignored, he can read only the text on the right half of the page.
• Autopagnosis (asomatognosia, agnosia of the body scheme) is a violation of recognition of parts of one's body, their location relative to each other. Her options are finger agnosia and a violation of recognition of the right and left halves of the body. The patient forgets to put on clothes on left extremities, wash the left side of the body. The syndrome most often develops in the defeat of the upper parietal and parieto-occipital regions of one (more often right) or both hemispheres. To identify auto-inflammation, the patient is offered to show the thumb of the right hand, the index finger of the left hand, touch the left ear with the right forefinger, and the index finger of the left hand touch the right eyebrow.