Organic dementia: main forms
The organic type of dementia develops as a result of structural brain damage and is subdivided into three key forms differing in the severity of the cognitive defect.
Total dementia Develops as a result of focal lesions of the frontal lobes, as well as diffuse inflammatory or atrophic processes in the brain.
- Cognitive sphere: Characterized by memory disorders of varying severity (from minimal to extremely severe). Patients completely lose the ability to think logically and comprehend the surrounding situation, leading to absurd, meaningless actions.
- Emotions and personality: Insight into their defect is completely absent. Mood is most often expressed as indifference or inadequate euphoria. The core of personality is completely destroyed.
Concentric dementia Arises as a consequence of traumatic encephalopathy or epilepsy.
- Cognitive sphere: Memory is strictly selective—patients easily absorb only the information that has practical significance for them. Thinking is characterized by pathologically increased viscosity and oligophasia. Patients are unable to comprehend abstract concepts, although they generally assess what is happening correctly.
- Emotions and personality: Critical attitude toward the illness is reduced: patients adapt to their status and treat it without anxiety. Extreme forms of egocentrism come to the fore.
Detailed profile of lacunar (dysmnestic) dementia
Lacunar dementia occurs against the background of diffuse vascular diseases. This is a milder variant of dementia in which the core of the personality remains intact (previous beliefs, attachments, and basic forms of behavior are preserved).
Intellect and memory The clinical core of this condition is a pronounced memory disorder, while the ability to form judgments and operate with concepts suffers to a significantly lesser degree. Logical abilities decline compared to the pre-morbid level, understanding of complex ideas becomes difficult, but the overall assessment of the situation remains adequate. Patients do not commit absurd actions.
Activity and skills Acquiring any new information is difficult. At the same time, old professional knowledge and automated skills can be preserved for a long time. In a complex work environment, patients look helpless, but cope with everyday tasks without problems.
Insight and emotional background A key feature of lacunar dementia is preserved insight.
- Patients are aware of their pathological condition, feel embarrassed by their forgetfulness, and apologize for it.
- Patients try to compensate for memory deficits (e.g., keeping notebooks for important notes).
- In communication with the physician, they are frank and actively complain about their health.
- The emotional sphere is dominated by depression, deep distress over their helplessness, tearfulness, and excessive sentimentality (emotional lability). There is "caricaturing"—a marked accentuation of character traits that were inherent to the person before the illness.
Schizophrenic dementia
This form represents a manifestation of terminal states in schizophrenia and differs cardinally from organic dementia in its clinical characteristics.
- Memory and comprehension: Unlike organic forms, memory retention processes are not impaired here. Comprehension of current events is also formally preserved, but this does not help the patient with social adaptation.
- Thinking: Deeply distorted. Paralogia, symbolism, loosening of associations, and a tendency toward fruitless philosophizing (over-inclusiveness/zerressen) are observed. Behavior becomes alogical and extremely passive.
- Emotions and personality: Critical attitude toward one's own condition is sharply reduced. Complacency and total indifference to the surroundings dominate. Personality changes manifest as autism, profound indifference, and abulia.
Briefly: answers to topical questions
What is the fundamental difference between acquired dementia and developmental delay (oligophrenia)?
Dementia is an acquired psychiatric defect with the loss of previously acquired knowledge and abilities, whereas oligophrenia is congenital mental deficiency characterized by general underdevelopment of the intellectual sphere. Developmental delay (DD) is a heterogeneous concept combining developmental lags of various etiologies; with proper training and correction, compensation is possible. If compensation does not occur and vital intellectual functions fail to form by the end of development, the diagnosis of mental retardation (oligophrenia) is established.
In which specific atrophic brain diseases does total dementia develop?
Total dementia develops in the following diffuse atrophic brain processes:
- Alzheimer's disease — accompanied by diffuse primary cortical atrophy (predominantly of the parietal and temporal lobes) and manifests as total dementia with gross impairment of practical skills.
- Senile dementia — an active atrophic process starting at ages 70–80, in which the psychiatric defect is more pronounced than in Alzheimer's disease.
Which specific diffuse vascular diseases lead to the development of lacunar dementia?
Among the specific diffuse vascular diseases leading to lacunar dementia, cerebrovascular atherosclerosis is prominent.
- Cerebrovascular atherosclerosis — a disease of the elderly with a chronic, undulating and progressive course. Its clinical picture includes memory impairment with preserved insight, and its outcome is lacunar dementia.
Overall, lacunar dementia is a characteristic manifestation in patients with vascular dementia.
What scales and tests are used for clinical assessment of dementia severity?
The following tools are used for clinical assessment of the severity of dementia and cognitive impairment:
- MMSE scale — used as a screening diagnostic method. Scores on this scale reflect the severity of disorders only approximately (maximum score is 30 points).
For detailed investigation of cognitive functions, neuropsychological tests are used:
- "100 minus 7" test (serial subtraction).
- Verbal fluency test (naming words in 1 minute).
- Constructive tests (copying figures).
- Trail Making Test.
Class and exam questions
In lacunar dementia, insight into one's condition and the core personality are preserved, and patients are capable of compensating for deficits. In total dementia, insight completely disappears and the personality disintegrates.
In lacunar dementia, insight into one's condition and the core personality are preserved, and patients are capable of compensating for deficits. In total dementia, insight completely disappears and the personality disintegrates.
Is memory impaired in schizophrenic dementia?
No, in the schizophrenic type of dementia, the ability to memorize information is not impaired. Disorders of thinking (over-inclusiveness, loosening of associations) and the emotional-volitional sphere come to the fore.
What does the term "caricaturing" mean in the context of dementia?
This is the accentuation of personality traits already present in the patient before the illness, characteristic of lacunar dementia (e.g., a thrifty person becomes miserly, and a neat person becomes pedantic).
What else to study on this topic
- Mechanisms of compensation for dysmnestic disorders
- Oligophasia and thinking viscosity in epilepsy
- Symbolism and paralogia in the structure of the schizophrenic defect
- Differential diagnosis of vascular and atrophic processes
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