Giving a correct definition of the concept of "mental retardation" (oligophrenia, dementia) is not easy, but in general, it represents an incomplete development of the psyche, accompanied by a manifestation of pronounced intellectual deficiency, difficulties or asocial development of the personality. It is a complex of pathological conditions congenital or acquired in childhood. The course of this disease is characteristically diverse, it has different degrees of severity. It is not possible to recover from mental deficiency. The author of the concepts of amentia, dementia and mental retardation is Philippe Pinel. This is a French psychiatrist who lived back in the 17th century.
The concept and signs of mental retardation
The symptoms of mental retardation have a different course depending on the severity and stage of development. In medicine, it is customary to distinguish several degrees of the disease. According to the concept of "mental retardation" and its classification, pathology is divided into three degrees depending on the ability of patients to learn and work:
- Moronity is a mild manifestation of the disease. The severity of underdevelopment is the weakest. Those suffering from the disease of this stage are characterized by a lack of the ability to form a complex conceptual apparatus and a slowdown in the development of thinking of an abstract type. Often the thoughts of such patients are possible only in a simplified form. As a result, the individual does not have the possibility of a holistic perception of the situation and the inner essence of events.
- A moderate degree of mental retardation corresponds to the concept of "imbecility". Patients are deprived of the ability to form a concept, only the formation of an idea is available to them. The possibility of abstract thinking and generalization is completely absent. However, despite this, imbeciles retain the ability to self-service. It is also possible to accustom them to light work, such as cleaning the premises, packing, etc. The vocabulary possessed by such patients is limited. Only speech of an elementary nature is accessible to their perception and understanding. In turn, the speech they possess consists exclusively of standard phrases, often without adjectives. Imbeciles have the ability to adapt only in the environment and environment that is familiar and standard for them. They are characterized by such traits as slovenliness, primitive interests, suggestibility.
- The most profound and severe of the degrees of mental retardation is idiocy. Patients susceptible to the disease of this phase are deprived of cognitive activity, the ability to respond to the environment, includingloud sounds and bright lights. There is no possibility of acquiring any self-service skills. The predominant part of such patients is characterized by a reduced degree of sensitivity, the expression of emotions of only a primitive nature, which most often includes anger and anger. They are deprived of the ability to rejoice and laugh, as well as cry. Their motor reactions are also primitive, chaotic and inconsistent.
Revealed the concepts of mental retardation in psychiatry Philippe Pinel. Further, it was supplemented by Soviet scientists.
Causes of mental retardation
The study of the concept of causes and forms of mental retardation has been going on for more than 100 years, but often, when considering an individual case, it is impossible to determine specific factors. A wide range of harmful effects can cause mental disorders and mental retardation.
Internal Causes
It is customary to refer to internal causes according to the works of F. Pinel (the one who introduced the concept of "mental retardation"):
- Mutational changes in the structure of chromosomes. Changes in the quantitative set and structure of chromosomes are a common cause of mental retardation. The manifestation of mutations during life is a natural and constant process. In addition, mutations can be caused by the harmful effects of chemicals (antitumor drugs, etc.) or by physical effects (X-rays, electromagnetic radiation). Also providefactors such as predisposition to impaired control of cell division at the gene level, as well as the age of the parents, are capable of influencing the appearance of mutations.
- Unfavorable, painful heredity. Such reasons include diseases of the endocrine system or defects in metabolic processes. The reason for the mental retardation of the child may be the diabetes of the mother. When the content of phenylalanine in the blood of the mother exceeds the norm (phenylketonuria), phenylalanine embryopathy occurs. Complex changes in spermatozoa and eggs, occurring from the beginning of their maturation to the formation of a zygote, indicate that the germ cells have become overripe. Such phenomena can be triggered by a hormonal disorder, but most often by an increase in the length of the period between ovulation and the fertilization of the egg.
Such changes can also cause mental retardation. The birth rate of children with trisomy 13, 18, 21 increases depending on the age of the parents. In this connection, such a factor as the age of the parents can provoke the development of mental retardation. This possibility is due to the aging that germ cells undergo, as well as an increase in the frequency of mutations, which can be caused by a decrease in enzyme activity, impaired chromosome resistance to harmful effects, and hormonal disruptions.
External causes (exogenous)
Define the concept of "mental retardation", "mental retardation"You can after familiarizing yourself with the causes and symptoms of these pathologies. There are many external factors that can affect the maturation of the fetus, causing damage. During the development of the fetus in the womb, its central nervous system has a special sensitivity, and therefore frequent damage is possible, resulting in mental underdevelopment. In addition, disorders in the development of the child's psyche may be due to harmful effects that affect the embryo in utero (in the prenatal period), as well as during childbirth (in the natal period) and in the early stages of the postnatal period.
Prenatal exposure
When mental retardation occurs, a high degree of importance is at what point in the development of the fetus the lesion occurs, how well its development proceeds, as well as the presence of tissues that are not damaged, capable of compensating for damage, as well as slowing down the development that were provoked infectious agent.
The earlier the harmful effect on the embryo in the first trimester is, the faster the malformations, pregnancy fading or miscarriage will occur. The most common causes of an underdeveloped psyche in the prenatal period are the reasons given below.
Fetal hypoxia is strongly associated with a high risk of having a baby with MR in mothers who suffer from the following serious illnesses:
- cardiovascular system;
- liver;
- thyroid;
- kidney;
- as well as diabetes.
Such painful conditions can be a provoking factor for the occurrence of prematurity or the manifestation of complications during childbirth.
Rhesus conflict
Incompatibility of ABO blood factors or Rh-factor incompatibility can serve as the cause of mental retardation. Approximately one in eight women does not have the Rh factor in their blood. Accordingly, the child is at risk of suffering from Rh incompatibility, in the case when such a factor is present in the blood of the father of the child. The Rh-positive fetus, which received this factor from the father, produces antibodies in the blood of the pregnant woman, when they enter the child's bloodstream, the destruction of erythrocytes occurs.
Infections
Erythroblastosis, which results from this, can lead to disruption of the development of the central nervous system. This, in turn, can later manifest itself in neurological diseases and mental retardation. Roughly 1 in 170 babies have erythroblastosis.
Many infections have the ability to be transmitted in utero from mother to fetus. But only a small percentage of them lead to the onset of mental retardation. Such infections cause damage to the central nervous system of the embryo in 5% of cases with severe MR and only 1% of mild cases.
Viruses
Among the microorganisms capable of causing mental retardation, the mostProtozoa and spirochete viruses are common. Viruses become the causative agent of infectious lesions of the fetus in 5% of pregnant women. Once in the mother's body, the infection may not have external manifestations and signs, but the fetus is still affected, which may be due to a lack of oxygen, malnutrition, or insufficiency of the blood-brain barrier. This, in turn, makes the fetal central nervous system an environment conducive to the development of microorganisms.
The main mechanism of damage to the nervous system of the fetus is a lack of oxygen (anoxia), leading to a h alt in cell division, resulting in deformities or limited organ growth. Another factor in the defeat of the fetus is the placenta, which provides a barrier for it, through which it is impossible to pass the pathogens of many acute infections. The effectiveness of such protection has a different degree for various pathogens of the virus.
The causative agents of toxoplasmosis and syphilis are able to penetrate the placental barrier, and also reach the fetus, getting to it from the amniotic fluid. Syphilis, which is congenital in nature, also causes the development of fetal MR. A mother infected during pregnancy is capable of transmitting syphilitic spirochete through the placenta. Spirochete enters the fetus only after the 5th month of pregnancy.
Reduce the degree of damage to the fetus allows the use of antibiotics. Maternal antibodies also protect the embryo from infections, but thismechanism is not effective in all situations. Having immunity to any disease, a pregnant woman can transmit the pathogen to the embryo. Listeria bacteria are able to bypass the barrier created by the placenta and damage the nervous tissues of the fetus, which can lead to meningoencephalitis, accompanied by severe organic lesions of the central nervous system, or death of the embryo.
Mother's illnesses
Thus, a disease such as listeriosis is another cause of severe mental retardation. Infrequent cases of the occurrence of VR in congenital fetal tuberculosis are noted. The causative agent of mental retardation can also be the influenza virus in the case of intrauterine infection.
A mother's illness with rubella in the first trimester of pregnancy leads to a risk of mental retardation in a born child with a probability of up to 20%. Infection of the salivary gland, getting to the fetus from a pregnant woman, contributes to inflammation of the membranes of the brain and cytomegaly, the consequences of which are severe diseases of the embryo and even its death. Other infections can also cause mental retardation. So, with toxoplasmosis, a person is infected with a single-celled microorganism (toxoplasma) by eating infected animal meat. The disease has a low prevalence as a congenital pathology in newborns. Infection is possible both after birth and before birth. Up to 10% of affected children die within 2months. A significant proportion of infants who survive face multiple malformations and mental retardation.
In addition to viral and infectious diseases that affect the fetus, various chemicals that have a harmful effect on the embryo and contribute to the formation of an intellectual defect in the child in the future can serve as causes of UO. Any of the harmful factors, such as drugs, lead, alcohol, can lead to fetal malformations and death.
Poison
Poisons may have a detrimental effect on the central nervous system, which do not affect organs that have already developed normally. Drugs that have a teratogenic effect (disturbing the development of the embryo and leading to various congenital developmental anomalies) include drugs aimed at suppressing metabolism, destroying cancer cells, etc. At the same time, some contraceptives, LSD and smoking abuse.
Also, the lack of vitamins A, B, pantothenic and folic acids, nutrients required for the body of a pregnant woman, can jeopardize the development of the intellectual abilities of a born child. The harmful effects that different substances have are also different:
- Anti-clotting drugs can cause brain hemorrhage and brain damage.
- Antimicrobials (sulfonamides)lead to brain damage due to the development of jaundice in the child.
The damage caused to the fetus by teratogenic drugs is also dependent on the time and method of exposure to a particular substance. Due to the genetic identity of each fetus, one agent is able to cause different reactions.
In addition to chemical factors, harmful effects on the embryo, followed by the onset of mental retardation, can also have factors of physical origin. So, the reason may be the effect of radiation on a woman during pregnancy during any therapeutic, diagnostic or other X-ray exposures.
Providing a teratogenic effect with the subsequent development of UO depends on the ongoing stage of embryo development, as well as on the power and dose of the radiation received and its type. Also, the individual characteristics of the sensitivity of the fetus play a role. The occurrence of defects under the influence of radiation is due to violations of metabolic processes and the degree of permeability of the cell membranes of the pregnant woman, as well as the presence of direct damage to the embryo.
Mental malformations can be caused by mechanical influences, which include:
- Excessive pressure of the uterus on the fetus (with large fibroids and oligohydramnios).
- Amniotic adhesions.
Also, the occurrence of malformations and mental retardation is likely in case of emotional stress during pregnancy, which are acute or chronic.
Influence in the natal period
Oxygen starvation (hypoxia) of the fetus often causes mental retardation of the child. If the process of childbirth is accompanied by oxygen deficiency, which can be caused by serious illnesses of the mother, fetal asphyxia occurs. Often, she is accompanied by birth injuries as a result of breech or facial presentation of the fetus, postmaturity or prematurity, prolonged or too rapid labor.
Postnatal exposure
The most common causes of mental retardation in the first years of life are the following conditions of the body:
- Severe intoxication;
- Clinical death;
- Tranio-cerebral injuries;
- Encephalitis;
- Severe exhaustion of the body.
Socio-cultural factors, in particular the family, have a major impact on the development of a child's personality and intelligence. Creating a favorable atmosphere in the family is a mandatory and extremely important condition for the necessary development of cognitive functions. The occurrence of mental retardation is possible in the absence of proper manifestation of social and psychological factors. The most susceptible to the influence of partial deprivation are children who have had multiple infectious diseases at an early age and who have congenital diseases. Children who have suffered brain injuries are characterized by increased fatigue during mental stress.
It is impossible to define the concept of "mental retardation" 100% correctly. Why? The point is that manyfactors causes any other manifestations that affect the expansion of the concept of mental retardation.
