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Classification of mental retardation
Last reviewed: 23.04.2024
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There are many authorial classifications of mental retardation, which are presented in the relevant publications. With clinical and pathogenetic differentiation of mental retardation, it is expedient to divide it into the following groups:
- exogenously conditioned, hereditary forms of brain damage that are not primarily associated with the formation of the anatomical and physiological basis of the intellect;
- light forms of mental retardation, due to the genetic variability of intelligence in the norm.
The clinical systematics of mental retardation is based on the widely used concepts of "differentiated" and "undifferentiated" mental retardation.
The group of clinically differentiated mental retardation includes nosologically independent diseases, for which mental retardation is only one of the symptoms, usually the most severe.
Classification of differentiated forms of mental retardation (GS Marincheva, MS Vrono, 1999).
Hereditary forms.
- Syndromes with multiple congenital anomalies.
- Chromosomal diseases.
- Genetic syndromes with an unclear type of inheritance.
- Monogeneously inherited syndromes.
- Hereditary metabolic defects.
- Fakomatosis.
- Neurological and neuromuscular diseases with mental retardation. Exogenously conditioned forms of mental retardation.
- Alcoholic fetopathy (fetal alcohol syndrome).
- Infectious embryofetopathy (ruberolar, toxoplasmosis, cytomegalovirus).
- Hemolytic disease of the newborn.
Mental retardation of mixed (hereditarily-exogenous) nature.
- Microcephaly.
- Hydrocephalus.
- Craniostenosis.
- Congenital hypothyroidism.
Clinically undifferentiated mental retardation is mental retardation, which does not have a specific clinical-psychopathological and somato-neurological picture of the disease. This group includes relatively light forms of intellectual insufficiency arising in families characterized by the accumulation of cases of mental retardation and the presence of microsocial conditions conducive to their occurrence. A mixed genesis, including a hereditarily deterministic low level of intellectual development and additional exogenous-organic effects in the early stages of ontogenetic development, is possible, which leads to an increase in the manifestations of mental retardation.
Many cases of undifferentiated mental retardation, which are mild in their manifestations, are considered in childhood as a retardation of mental development, at an older age as a borderline mental retardation or as an extreme variant of a low intellectual level in biologically valuable individuals.
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