Lecture
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the productivity of reproduction during memorization,which in some cases can lead to the depletion of the function and the deterioration of the initially achieved performance.
Particularly distinctly modal-specific disturbances of the hearing-speech memory occur in the conditions of the interfering activity that fills the short time interval between memorization and reproduction (for example, a small conversation with the patient).
At the heart of the impaired hearing-speech memory are changes in the neurodynamic parameters of the analyzer in the form of pathological retro-and proactive inhibition and equalization of excitability.
The deceleration of hearing-speech traces is manifested not only in connection with the introduction of a special interfering task, but also as a result of the mutual influence of the elements of the acoustic sequence on each other (intrastimulus interference) leading to a narrowing of the volume of direct reproduction. The mechanism of equalization of excitability causes the appearance of paraphasia when the patient reproduces verbal material, i.e. replacement of stimuli by words that are similar in sound (literal paraphasias) or in meaning (verbal paraphasias).
In conclusion of the description of disorders of hearing-speech memory, it should be noted that the degree of their severity depends on the nature of the memorized material. Verbal material, combined with internal semantic connections (phrases, stories), is remembered by patients easier than a series of words that are not related to each other. But even inside the semantic information, the factor of its volume plays a role: phrases are reproduced better than stories.
Why are these disorders considered in the framework of speech disorder syndrome (aphasia)? The fact is that, firstly, the lack of aural-speech memory can lead to a disturbance in the patient's understanding of the speech addressed to him, verbal instructions, to a drastic restriction of the ability to operate with the hearing-speech material "on the tracks." Secondly, with increasing verbal "load" in the form of an increase in the volume of auditory material, symptoms characteristic of sensory aphasia can occur: the alienation of the meaning of the word and errors in the differentiation of phonemes. So, for example, the instruction to show parts of the body (“nose”, “eye”, “ear”) is correctly performed by patients with a single presentation of verbal equivalents, and in tasks that require retention of the display sequence (show “ear-nose-eye”),when properly repeated, errors occur in the identification of the relevant parts of the body.
The defeat of the symmetric parts of the right hemisphere of the brain leads to impaired memory for nonverbal and musical sounds, which is manifested in the difficulties of memorizing rhythmic structures with an increase in the volume of elements contained in them and the number of groupings, as well as in the impossibility of reproducing a given melody. At the same time, the processes associated with speech activity are also affected: the perception of intonation components, the determination of the belonging of a voice to a person of a certain gender and age. The possibility of individual identification of votes is violated.
The interaction of the brain hemispheres is manifested here and in the organization of the hearing-speech memory. The diagnostic arsenal of techniques, which allowed to speak with confidence about the own contribution of the temporal regions of the right hemisphere of the brain to speech processes, included a test that tested the ability to reproduce the order of elements in a word sequence. In the case of performing a task to reproduce a series of 5 words, patients with lesions of the temporal regions of the right hemisphere of the brain during the first reproduction reveal difficulties that are outwardly similar to the narrowing of the volume of direct reproduction during acoustic-mnestic aphasia. Repeated presentation of the material (memorization) reveals several clear differences in these initially similar symptoms. First of all,incomplete reproduction in hemispheric patients is extremely rarely represented by the "margin factor"; Actualized words do not correspond to their position in the series and the sequence. Secondly, memorization can lead to a complete reproduction of a given volume (as opposed to left-hemispheric lesions), however, the assimilation of a sequence of words in a series lags significantly behind the performance of the task in terms of volume. In a significant number of cases, it is generally not possible to obtain its stable reproduction. Thirdly, the introduction of the interfering task does not reduce the achieved level of reproduction. Fourthly, often the patient is not able to give an answer after the first presentation of a series of words, how many elements it consists of, while a patient with a left hemisphere focus usually controls the general structure of the verbal row.factor of the edge "; actualized words do not correspond to their position in the series and order. Secondly, memorization can lead to full reproduction of a given volume (as opposed to left-hemispheric lesions), however, the assimilation of the sequence of words in the series significantly lags behind the task in terms of volume. In a significant number of cases, it is not possible to obtain its stable reproduction at all. Third, the introduction of an interfering task does not lead to a decrease in the achieved level of reproduction. Fourth, often a patient e is able to give an answer after the first presentation of a series of words, how many elements it consists of, while a patient with a left hemisphere focus usually controls the general structure of the word series.factor of the edge "; actualized words do not correspond to their position in the series and order. Secondly, memorization can lead to full reproduction of a given volume (as opposed to left-hemispheric lesions), however, the assimilation of the sequence of words in the series significantly lags behind the task in terms of volume. In a significant number of cases, it is not possible to obtain its stable reproduction at all. Third, the introduction of an interfering task does not lead to a decrease in the achieved level of reproduction. Fourth, often a patient e is able to give an answer after the first presentation of a series of words, how many elements it consists of, while a patient with a left hemisphere focus usually controls the general structure of the word series.memorization can lead to a complete reproduction of a given volume (as opposed to left hemispheric lesions), but the assimilation of a sequence of words in a series lags significantly behind the performance of the task in terms of volume. In a significant number of cases, it is generally not possible to obtain its stable reproduction. Thirdly, the introduction of the interfering task does not reduce the achieved level of reproduction. Fourthly, often the patient is not able to give an answer after the first presentation of a series of words, how many elements it consists of, while a patient with a left hemisphere focus usually controls the general structure of the verbal row.memorization can lead to a complete reproduction of a given volume (as opposed to left hemispheric lesions), but the assimilation of a sequence of words in a series lags significantly behind the performance of the task in terms of volume. In a significant number of cases, it is generally not possible to obtain its stable reproduction. Thirdly, the introduction of the interfering task does not reduce the achieved level of reproduction. Fourthly, often the patient is not able to give an answer after the first presentation of a series of words, how many elements it consists of, while a patient with a left hemisphere focus usually controls the general structure of the verbal row.In a significant number of cases, it is generally not possible to obtain its stable reproduction. Thirdly, the introduction of the interfering task does not reduce the achieved level of reproduction. Fourthly, often the patient is not able to give an answer after the first presentation of a series of words, how many elements it consists of, while a patient with a left hemisphere focus usually controls the general structure of the verbal row.In a significant number of cases, it is generally not possible to obtain its stable reproduction. Thirdly, the introduction of the interfering task does not reduce the achieved level of reproduction. Fourthly, often the patient is not able to give an answer after the first presentation of a series of words, how many elements it consists of, while a patient with a left hemisphere focus usually controls the general structure of the verbal row.controls the overall structure of the word series.controls the overall structure of the word series.
A possible mechanism underlying the described variant of the impaired hearing-speech memory in patients with lesions of the temporal regions of the right hemisphere of the brain is the insufficiency of direct memorization, the formation of a "perceptual scheme" of the memorized stimulus material. Interestingly, this defect can be overcome if the words presented are either divided intonationally into groups ("house-forest-cat" - pause - "night-ringing"), or increase the interstimulus intervals.
In favor of the assumption of a violation of the simultaneous "seizure" of the integrity of the memorized structure is evidenced by the violation of the reproduction of the visually presented figure of Ray-Taylor. In this sense, the defect of the hearing-speech memory in right-hemispheric foci within the extra-nuclear parts of the temporal region is not modal-specific, but carries a reflection of one of the basic factors in mental activity provided by the right hemisphere, simultaneous perception and actualization. Nevertheless, it is important to note that the right hemisphere contributes to the organization of the verbal-mnestic function at a certain stage of its deployment.
Syndromes of the lesion of the medial parts of the temporal region are not fully understood and described. As already mentioned, this area of the brain is related, on the one hand, to such basal functions in brain activity and mental reflection as an emotional-needy sphere, and thus to the regulation of activity. On the other hand, with the defeat of these systems, there are disorders of the highest level of the psyche - consciousness, as a generalized reflection of the current situation by a person in its relationship with the past and future and himself in this situation.
Clinical observations show that focal processes in the medial regions of the temporal lobes may manifest as affective disorders like exaltation or depression, as well as paroxysms of anguish, anxiety, and fear combined with conscious and experienced vegetative reactions. Often, as symptoms of irritation, disturbances of consciousness can occur in the form of absences and such phenomena as "deja vu" and "jamais vu", disorientation of orientation in time and place, as well as psychosensory disorders in the auditory sphere (verbal and non-verbal auditory deception, as a rule, critical attitude towards them on the part of the patient), distortion of taste and olfactory sensations. All these symptoms can be identified in a conversation with the patient and in monitoring his behavior and emotions during the examination.
The only systematically (clinically and experimentally) investigated disorder associated with the pathology of the medial regions of the temporal region is memory impairment. The development of these ideas was largely facilitated by the data obtained during operations on the medial temporal structures aimed at the surgical treatment of severe forms of epileptic disease.
Memory impairment in this syndrome is characterized by the following symptoms. They are modally nonspecific in nature, occur as anterograde amnesia (memory of the past remains relatively intact), combined with impaired orientation in time and place. In most cases, they are similar to those described by SS. Korsakov and are designated as amnestic (or Korsakov) syndrome. Patients are aware of their defect and seek to compensate for it by actively using the recording system.
Clinical and experimental study of the structure and mechanisms of the amnestic syndrome at this localization shows that the volume of direct memorization in these patients corresponds to the lower limit of the norm and is 5-6 elements, while memorizing their number may increase. The 10-word learning curve has a visible tendency to rise, although the learning process is extended over time and the level of achievement may fluctuate. Patients can hold a series of 4-5 items for an empty pause of 2 minutes. Patients begin to recognize the attending physician over time, remember the procedures or examinations they had transferred. These facts indicate that the process of recording information in memory is relatively preserved. At the same time, there are distinct difficulties in reproducing current events and experimental material,which are easily objectified when introduced between memorization and reproduction of an interfering task, the negative impact of which depends on its content. For example, when memorizing a sequence of words after its immediate reproduction, one can set a patient several arithmetic examples (heterogeneous interference), name a few words with the letter “k” (homogeneous interference based on the similarity of the verbal content of the material being memorized and the interfering activity). Finally, after memorizing one series of words, it is proposed to memorize a similar second series (homogeneous interference, similar to primary memorization and in content and in the mnestic task). In all cases, after the interfering activity, the reproduction will be deficient, and the forgetting will be all the more profoundthe more homogeneous in its content and purpose the interfering activity of the preceding memorization.
The interfering activity carried out in the interval of deferment between memorization and reproduction has an inhibitory, blocking effect on the updating of the material that has just been memorized.
Clinical and experimental data allow us to speak about the main mechanism of the formation of the amnestic syndrome in case of damage to the medial parts of the temporal systems of the brain - pathological inhibitory traces of interfering influences, i.e. consider memory impairment due to changes in the neurodynamic parameters of brain activity toward the predominance of inhibitory processes.
It is characteristic that if this level is defeated, memory impairments appear in a “pure” form without recruiting side elements into the product. The patient either calls a few available words actualization, noting that he forgot the rest, either says that he forgot everything, or amnesizes the fact of memorization preceding the interference. This feature indicates the preservation of control over the activity of reproduction. In addition to the sign of modal non-specificity, the described memory disorders are characterized by the fact that they “capture” various levels of the semantic organization of the material (series of elements, phrases, stories), although semantic constructions are memorized somewhat better and can be reproduced using prompts. In some cases, the story can be reproduced better than a series of words or a phrase, especiallyif the patient understood its meaning well (cf. with impaired hearing-aural memory).
As part of the study of this syndrome, one essential question remains: is it a result of bilateral or unilateral lesion of the medial regions of the temporal region? There is reason to consider it as a consequence of the bilateral pathological process. However, these bases are not completely valid. It can only be recommended not to be limited to the study of mental disorders, but to look for (or exclude) signs of unilateral deficiency in other mental processes.
The most common clinical model of the pathological process in the basal regions of the temporal systems are tumors of the wings of the main bone in the left or right hemispheres of the brain.
Left-sided localization of the lesion in this case leads to the formation of a syndrome of impaired hearing-speech memory, which differs from the similar syndrome in acoustic-mnestic aphasia. This difference concerns two components of the latter: signs of proper speech dysfunction and narrowing of the volume of hearing-speech perception. With the defeat of the temporal-basal parts, the main radical determining the nature of memory disorders is the increased inhibition of verbal traces by interfering influences under conditions of homogeneous interference, i.e. when memorizing and reproducing two "competing" series of words, two phrases and two stories. A noticeable narrowing of the volume of hearing-speech perception is not observed, as well as signs of aphasia.However, in this syndrome there are signs of inertia in the form of repetition when playing the same words. In tests for the reproduction of rhythmic structures, patients hardly switch when moving from one rhythmic structure to another; Perseveratic performance is observed, which, however, is amenable to correction. It cannot be ruled out that pathological inertness in this case is associated with the influence of the pathological process either on the basal parts of the frontal lobes of the brain or on the subcortical structures of the brain, especially since at this localization the tumor can disrupt blood circulation in the system of subcortical zones.amenable to correction. It cannot be ruled out that pathological inertness in this case is associated with the influence of the pathological process either on the basal parts of the frontal lobes of the brain or on the subcortical structures of the brain, especially since at this localization the tumor can disrupt blood circulation in the system of subcortical zones.amenable to correction. It cannot be ruled out that pathological inertness in this case is associated with the influence of the pathological process either on the basal parts of the frontal lobes of the brain or on the subcortical structures of the brain, especially since at this localization the tumor can disrupt blood circulation in the system of subcortical zones.
The defeat of the basal-temporal divisions in the right hemisphere of the brain is manifested in the difficulties of reproducing the order of the elements and corresponds to the (b) disorders described above, which manifest themselves here only in a milder form.
Completing the description of the pathology associated with the lesion of various parts of the temporal systems of the brain, one should dwell on two important moments in the diagnostic aspect.
The depth location of the pathological focus in the temporal regions of the brain reveals itself not so much as primary impairment, but rather as a disorder of the functional state of the systems within the temporal zone, which in a clinical neuropsychological examination situation manifests itself in partial exhaustion of the functions associated with these zones. For example, testing phonemic hearing can detect its safety when performing two or three first differentiations. However, the continuation of this task causes errors in the differentiation of phonemes. In fact, in conditions of exhaustion of function, there are genuine violations of phonemic hearing, which cannot be considered as a result of cortical insufficiency proper,and must be interpreted in connection with the influence of the deeply located focus on the secondary sections of the temporal region of the left hemisphere of the brain. Similarly, with deep tumors, other symptoms characteristic of the described syndromes of focal pathology in the temporal regions of the brain may also appear. Dissociation between the initially available sampling and the appearance of pathological symptoms during the "load" on the function gives grounds for a conclusion about the predominant influence of the deeply located focus on convexital, medial or basal structures in the left or right hemispheres of the temporal regions of the brain.Dissociation between the initially available sampling and the appearance of pathological symptoms during the "load" on the function gives grounds for a conclusion about the predominant influence of the deeply located focus on convexital, medial or basal structures in the left or right hemispheres of the temporal regions of the brain.Dissociation between the initially available sampling and the appearance of pathological symptoms during the "load" on the function gives grounds for a conclusion about the predominant influence of the deeply located focus on convexital, medial or basal structures in the left or right hemispheres of the temporal regions of the brain.
The second important diagnostic point concerns the difficulties of determining the local lesion of the right temporal lobe. It must be borne in mind that, as shown in a number of studies, the right hemisphere compared to the left reveals a less pronounced differentiation of structures in relation to individual components of mental functions and the factors that provide them. In this regard, the interpretation obtained by neuropsychological examination syndromes and their constituent symptoms in a narrowly local sense should be more cautious.
Часть 1 Major neuropsychological syndromes with local brain lesions
Часть 2 - Major neuropsychological syndromes with local brain lesions
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Neuropsychology
Terms: Neuropsychology