Mental retardation (MR) occurs as a group of disorders in which general intellectual functioning is significantly lower than that of the same age during the developmental period and is accompanied by adaptive behavior deficits in the same amount. Mental retardation is known by various names. Psychiatry is called mental retardation, mental underdevelopment, and mental deficiency. Education and psychology are called mental retardation and mental deficiency. Pediatrics is called mental retardation, mental retardation, and intellectual developmental disorders. Special education school called mental retardation, intellectual disability.
[Epidemiology
According to the American Association of Mental Retardation (AAMD) and WHO, the prevalence of MR in children is 1% to 2%. The total prevalence of MR in children aged 0-14 years in China is 1.20%; the prevalence tends to increase with age.
Etiology and pathology
There are many factors affecting children’s intelligence, including biological, environmental, psychological, genetic, nutritional, family, social, economic, and geographical factors, and these factors are interrelated and affect each other.
(i) Heredity
(ii) Infection
(iii) Nutrition
(iv) Perinatal factors
(E) Psychosocial factors
(F) Environmental factors
1.Geographical environment
2.Noise
3.Radiation
4.Heavy metals
(vii) Family factors
(H) Unknown etiology
Clinical manifestations
MR is generally classified as mild, moderate, severe and very severe based on IQ and adaptive behavior deficits.
1, mild MR Psychiatry is also known as stupidity.
IQ is 50-70, and adaptive behavior is mildly deficient. Early development is slightly delayed compared to normal children, and is not as active as normal children, and lacks interest in the surrounding things. They may follow the rules or act roughly. Speech development is slightly delayed and abstract vocabulary is poorly acquired. Poor analytical ability and superficial understanding of problems. They can recite texts but cannot use them correctly, and have difficulty completing arithmetic applications. Through special education, they can acquire practical skills and useful reading and billboard abilities. When they grow up, they can do general household chores and simple concrete work. Lack of initiative and dependence in all matters, not good at coping with changes in the outside world, easily influenced and dominated by others. Can adapt to society under guidance.
2.Moderate MR is also called foolishness.
IQ is 35-49, with moderate deficits in adaptive behavior. The whole development is delayed compared with normal children. The language function is not fully developed, the words are unclear, the vocabulary is lacking, only simple concrete thinking can be carried out, and abstract concepts are not easily established. They have poor discrimination of their surroundings and can only recognize superficial and fragmentary phenomena. They cannot make progress in reading and arithmetic. With long-term education and training, they can learn simple interpersonal skills, basic hygiene and safety habits, and simple manual skills.
3.Severe MR is also called demented.
IQ is 20-34, with severe deficits in adaptive behavior. Delayed development in all aspects of early life. Ambiguous pronunciation, minimal speech, and very poor self-expression. Lack of abstract concepts and low comprehension. Emotional naivety. Very clumsy movements. There is some defensive ability to avoid apparently very dangerous. With systematic habit training, they can develop simple living and hygiene habits, but need to be cared for by others. When they grow up, they can do some fixed and minimal physical work under supervision.
4. Very severe MR, also known as idiot.
IQ is below 20 and adaptive behavior is extremely deficient. Does not understand everything around him/her. Lack of language function, at most can call out “Dad”, “Mom”, etc., but can not really identify Mom and Dad, often unconscious howling. Lack of self-protection instincts, not knowing how to avoid obvious dangers. Emotional responses are primitive. Sensation and perception are markedly diminished. Significant motor dysfunction with inflexible arms and legs or lifelong inability to walk. Multiple disabilities and recurrent seizures are often present. Personal life is unmanageable and most die early in life. Survivors can respond to skillful training of the arms and legs.
[Diagnosis
(A) Medical history collection
1. Family history: We should find out whether the parents are inbred, and whether there are blind, mute, epileptic, cerebral palsy, congenital malformation, MR and psychiatric patients in the family.
2. Pregnancy history of the mother: Ask the mother if there is any viral infection, miscarriage, bleeding, injury in early pregnancy, if she is taking chemical drugs, exposed to toxins and rays, if she is suffering from hypothyroidism, diabetes and severe malnutrition, if there are multiple births, excessive amniotic fluid, placental insufficiency, mother-infant blood type incompatibility.
3. Birth history: whether the birth was premature or overdue, whether there was any abnormality in the mode of delivery, whether the birth weight was low, whether there was asphyxia, birth injury, intracranial hemorrhage, severe jaundice and congenital malformation after birth.
4, growth and development history: including neuropsychiatric morbidity, such as the time of the beginning of large movements such as lifting the head, sitting up, walking, the completion of fine movements such as detecting small toys and daily objects with fingers, the developmental status of language functions such as calling out to mom and dad, understanding speech, and other intellectual behavioral performance such as feeding, dressing and controlling urination and defecation.
5. History of past and present diseases: any cranial trauma, hemorrhage, central nervous system infection, serious systemic infection, convulsive seizures, etc.
(B) Physical examination
(C) Developmental examination
(D) Neuropsychiatric examination
(V) Laboratory examination
Laboratory tests include biochemical examination of blood, urine, brain and spinal fluid, cranial X-ray and CT examination, cerebral angiography, electroencephalography, evoked potentials, audiometry, chromosome analysis, determination of pituitary, thyroid, gonadal and adrenal functions, virus (such as cytomegalovirus, rubella virus), protozoa (such as toxoplasmosis) and antibody examination. The relevant items should be selected according to the diagnostic needs.
(vi) Intelligence tests and behavioral evaluation
In mild MR, intelligence tests are often used, but in severe MR, it is often difficult to use intelligence tests and must rely on behavioral assessment scales, which are not as reliable as intelligence tests in identifying mild MR. Therefore, the two methods should be used together, and the results of the examination must be analyzed comprehensively.
Intelligence testing methods
(A) Intelligence test
1.Screening method
(1) Denver developmental screening test (Denver developmental screening test, DDST): applicable to children from birth to 6 years old, the method is easy to operate, spend less time, simple tools, reliability and validity are good.
(2) Human drawing test: The test is used to determine the level of intellectual development by scoring according to the human figure drawn, and is suitable for screening the intelligence of children aged 5 to 12.
2.Diagnostic method
(1) Wechsler Intelligence Scale for Children (WISC-CR): applicable to children aged 6 to 16 years.
(2) China-Wechsler Intelligence Scale for Young Children (CWYCSI): applicable to children aged 4 to 6.5 years.
(3) Gessell ScaleR: applicable to children aged 0 to 3 years.
(B) Adaptive behavior assessment method
(1) Infant and Toddler – Junior High School Student Social Life Ability Scale is applicable to children aged 6 months to 13 to 15 years old. This scale is an indispensable tool for diagnosing MR and grading.
2.Neonatal Behavioral Neurological Scoring (NBNA) The National Association Group has determined the normal range of NBNA for newborns nationwide through investigation and research, and its clinical should be carried out gradually.
[Differential diagnosis
1.Children’s autism Most children with autism have varying degrees of intellectual deficits, but mainly have impairments in social interaction, quality of language communication, stereotyped and repetitive movements, compulsive adherence to the same way and other bizarre behaviors.
2.Children’s schizophrenia Most of them start after the age of 7 or 8, with incoherent thinking, delusions, hallucinations, and emotional indifference, etc. Except for the decline period, the general intellectual defects are not obvious.
3.Organic psychosis With a history of infection, poisoning, trauma, etc. or neurological signs, although accompanied by intellectual deficits, but not as comprehensive as mental retardation, but less impaired in life skills and other aspects.
Treatment
1.Etiology treatment
If the cause has been identified, such as chronic diseases, poisoning, long-term malnutrition, hearing and visual impairment, then we should try to remove the cause as much as possible, so that the intelligence can be partially or completely restored. Children with hypothyroidism, phenylketonuria and other endocrine metabolic abnormalities should be diagnosed early, and thyroid hormone replacement or special diet therapy for phenylketonuria should be used early to improve their intellectual level. For MR caused by psychosocial and cultural reasons, changing environmental conditions, allowing them to live in friendly and harmonious families, and strengthening their upbringing will enable them to make trap progress in intelligence.
2.Training and rehabilitation
In conjunction with the application of medical, social, educational and vocational training measures, patients are trained to achieve the highest possible level of intelligence according to their age and the severity of their MR.
[Prevention
(i) Primary prevention
①Health education and nutritional guidance.
②Prenatal and perinatal health care (management of high-risk pregnancy, neonatal intensive care, discouraging pregnant women from drinking and smoking, avoiding or stopping drugs that adversely affect fetal development);
(iii) Immunization against infectious diseases (viruses, bacteria, protozoa).
(ii) Secondary prevention
(i) follow-up of high-risk newborns, early detection of diseases and treatment, with particular attention to the fact that early nutrition (protein and trace elements such as iron and zinc) supply and appropriate environmental stimulation have a good effect on intellectual development.
(ii) Regular health examinations of preschool children (physical, nutritional, psycho-psychological development, visual and auditory) ;
③ screening for metabolic disorders (e.g. hypothyroidism, phenylketonuria) in newborns
(iv) Prenatal diagnosis and amniotic fluid screening (chromosomal disorders, neural tube abnormalities, metabolic disorders).
(iii) Tertiary prevention
Comprehensive prevention requires the collaboration of society, school and family on each side. Early detection of MR, early intervention and stimulation; effective assistance to the family to keep the family structure intact, resulting in improved functioning of the child with MR.
The fundamental way of prevention is to deepen the research on the etiology of MR, and only by taking measures to address the causes can prevention be more effective.