Low IQ

Introduction to mental retardation Mental retardation (MR) is a group of diseases in which the general intellectual function is significantly lower than the same age level and the same amount is accompanied by adaptive behavioral defects. IQ (IQ) is lower than the population mean of 2.0 standard deviation (the IQ of the population is set at 100, the IQ value of a standard deviation is 15), and the general IQ below 70 (or 75) is that the intelligence is significantly lower than the average. Adaptive behavior includes both personal life ability and social responsibility. Developmental period generally refers to under 18 years of age. Mental retardation Psychiatry is also known as "mental retardation", "mental hypoplasia", and "mental defects." Education and psychology are called "intellectual backwardness" and "intellectual defects." Pediatrics is called "intellectual depression," "smart retardation," and "intellectual developmental disorders." Special education schools are called mental disability and intellectual disability. basic knowledge The proportion of illness: 0.001% Susceptible people: no specific population Mode of infection: non-infectious Complications: epilepsy

Mental retardation

Infection (20%):

Poisoning accounted for 12.3%, infection pointed to brain infections before and after life, such as rubella, cytomegalovirus, toxoplasma, herpes simplex virus and many other viral infections, including hyperbilirubinemia, toxemia, lead poisoning , alcoholism and long-term use of excessive amounts of phenytoin or phenobarbital.

Injury and hypoxia (10%):

Brain injury can occur due to physical or mechanical factors during childbirth, such as birth injury, craniocerebral trauma, perinatal or postnatal hypoxia can also damage brain tissue, such as severe blood loss, anemia, heart failure, lung disease And neonatal asphyxia, intracranial hemorrhage, etc., as well as drowning, anesthesia accident, cerebral hypoxia after epileptic seizures.

Metabolism (10%):

Nutrition and endocrine diseases account for 5.8%. The metabolism of amino acids, carbohydrates, fats, mucopolysaccharides, sputum and other substances in the body can affect the development and function of nerve cells, such as phenylketonuria, galactosemia, during and after birth. Insufficient nutrition, especially protein, iron and other substances will reduce the number of brain cells in the fetus, infants, or hypofunction. Endocrine disorders also affect mental development, such as hypothyroidism.

Chromosomal aberrations (10%):

Chromosomal aberrations include changes in the number or structure of autosomes or sex chromosomes, such as congenital, trisomy 18, trisomy C, meow syndrome, fragile X syndrome, congenital testicular hypoplasia syndrome, Congenital ovarian hypoplasia syndrome.

Psychosocial factors (10%):

Children with no organic lesions of the brain are mainly caused by adverse environmental factors such as neuropsychological damage and sensory deprivation, such as severe lack of early appropriate stimulation and education.

Mental retardation prevention

The prevalence of MR varies according to the definition of MR, the diagnostic criteria, the sampling method and the method of psychological testing prescribed by each survey. According to the American Association of Mental Retardation (AAMD) and WHO, the prevalence of MR in children is 1%. 2%, the National Collaborative Group conducted a survey of 85,170 children in the administrative regions of North China, Northeast China, Northeast China, East China, Southwest China, and the administrative divisions on May 1, 1988. The prevalence rate was 1.20%; the total prevalence rate was 0.70% in urban areas, 1.41% in rural areas; the total prevalence rate of boys was 1.24%, and that of girls was 1.16%; the total prevalence rate of children under 3 years old was 0.76%, children aged 3-7 years old. 1.10%, 1.44% of children aged 7 to 11 years old, 1.50% of children aged 11-14 years, the prevalence rate increased with age; the prevalence of MR was different under different neuroeconomic and cultural conditions, the city was 0.78%. The rural area is 2.41%, the mountain area is 3.84%, and the minority is 3.60%.

1, primary prevention

Including the following: 1 health education and nutrition guidance; 2 prenatal and perinatal care (high-risk pregnancy management, neonatal intensive care, discourage pregnant women from drinking alcohol, avoid or stop drugs that have adverse effects on fetal development); 3 infection Immunization of diseases (viruses, bacteria, protozoa); 4 genetic metabolism examination and consultation (avoiding close relatives marriage, found carriers); 5 environmental protection (preventing physical and chemical pollution, poisoning and noise damage); 6 reducing craniocerebral trauma and accidents Correctly treat brain diseases and control seizures; 7 strengthen preschool education and early training; 8 prohibit neglect and abuse of children, and take the above measures to prevent the occurrence of MR.

2, secondary prevention

The measures include: 1 Follow-up of high-risk newborns, early detection of diseases, treatment, especially attention, early nutrition (protein and iron, zinc and other trace elements) supply and appropriate environmental stimulation have a good effect on mental development; 2 pairs of school age Pre-school children undergo regular health checks (physical, nutritional, mental and psychological development, visual and auditory); 3 neonatal metabolic diseases (such as hypothyroidism, phenylketonuria) screening; 4 prenatal diagnosis, amniocentesis (chromosome disease, Neural tube defects, metabolic diseases), secondary prevention mainly lies in early diagnosis and special treatment.

3, three levels of prevention

It is necessary for society, schools, and families to cooperate in comprehensive prevention, early detection of MR, early intervention and stimulation; effective help to families, maintain family structure, and improve the function of MR children.

The fundamental way of prevention is to continuously deepen the study of the etiology of MR. Only by taking measures against the cause can prevention be more effective.

Mental retardation Complications

If the condition is extremely serious, the patient's feelings and perceptions are obviously reduced, the motor function is significantly impaired, the hands and feet are inflexible or can not walk for a lifetime, and there are often multiple disability and epileptic seizures, personal life can not be dealt with, most of the early deaths, survivors' skills on the feet Training can be responsive.

Mental retardation symptoms common symptoms brain developmental disorders infants speak late convulsions

MR is generally classified into four grades of mild, moderate, severe, and extremely severe according to IQ and adaptive behavioral defects.

1. Mild MR psychiatry is also called stupid

The IQ is 50 to 70, and the adaptive behavior is mildly defective. Early development is slightly slower than normal, and not as lively as normal children, lacking interest in things around. Do things or follow the rules, or act rudely. Speech development is slightly late, and abstract vocabulary is less. Poor analytical skills and superficial problems. The academic performance is worse than that of the average child. It can recite the text, but it cannot be used correctly. It is difficult to complete the arithmetic application. Practical skills and practical reading and billboard capabilities are available through special education. When grown up, you can do general housework and simple specific work. There is a lack of opinion and dependence, and it is not good at coping with changes in the outside world. It is vulnerable to the influence and control of others. Can adapt to society under the guidance.

2. Moderate MR is also called ignorance

The IQ is 35 to 49, and the adaptive behavior is moderately defective. The whole development is slower than normal children. The language function is incomplete, the words are unclear, the vocabulary is lacking, and only simple concrete thinking can be carried out. The abstract concept is not easy to establish. The ability to distinguish the surrounding environment is poor, and only the surface and fragmentation of things can be recognized. No progress can be made in reading and computing. After long-term education and training, you can learn simple interpersonal effects, basic hygiene habits, safe habits and simple manual skills.

3. Severe MR, also known as ignorance

The IQ is 20 to 34, and the adaptive behavior is severely deficient. All aspects of development were slow in early years. The pronunciation is vague, the speech is very small, and the self-expression ability is extremely poor. Lack of abstract concepts and low understanding. Emotional childishness. The action is very clumsy. Have a certain degree of defense ability, can avoid obvious danger. After systematic training, you can develop simple living and hygiene habits, but life needs the care of others. When you grow up, you can do some fixed and simple physical labor under supervision.

4. Extremely heavy MR, also known as idiot

IQ is below 20 and the adaptive behavior is extremely flawed. Do not understand everything around. Lack of language function, at most will call "dad", "mother", etc., but can not really identify parents, often unconscious screaming. Lack of self-protection instinct, do not know to avoid obvious dangers. The emotional response is primitive. Feelings and perceptions are significantly reduced. The motor function is significantly impeded, the hands and feet are not flexible or can not walk for life. There are often multiple disability and epileptic seizures. Personal life can't be dealt with, and most of them die early. Survivors can react to the skill training of their opponent's feet.

Inferiority check

First, neuropsychiatric examination

Second, laboratory inspection

Laboratory tests including blood, urine, brain, spinal biochemical examination, cranial X-ray and CT examination, cerebral angiography, electroencephalogram, evoked potential, audiometry, chromosome analysis, pituitary, thyroid, gonad, adrenal function measurement, virus (such as cytomegalovirus, rubella virus), protozoa (such as toxoplasma) and antibody testing, etc., should be selected according to the needs of the diagnosis.

Third, intelligence test and behavior judgment

Mild MR multi-use intelligence test, severe MR above is often difficult to use the intelligence test method, must rely on the behavior rating scale, and the rating scale is not as reliable as the intelligence test when identifying mild MR, so the two methods should be used together. The results of the inspection must be comprehensively analyzed.

Intelligence test method

(1) Screening method According to the general intelligence test method, it often takes a long time, sometimes it takes 1~2 hours or more, which is not suitable for general pediatrician or pediatric health screening. Therefore, some simple screening methods are used. Most of the contents are selected from various classic intelligence test methods. The test takes only a short time, and the suspicious cases can be initially screened. The screening results can only be used as a basis for further examination. Therefore, the diagnosis is made. At present, the commonly used screening methods in China are as follows.

1 Denver developmental screening test (DDST): suitable for children from birth to 6 years old, the method is simple and easy to operate, it takes less time, the tool is simple, the reliability and validity are good, this method has been widely used all over the world. Adopted, China began to apply this method in the early 1980s. Shanghai, Beijing and other places standardized the DDST according to the characteristics of China's society, economy, language, culture, educational methods and geographical environment, and mapped the screening of children's intellectual development. Scale (DDST-R).

2) Painter's test: According to the drawn human form, the score of mental development is judged, and it is suitable for children's intelligence screening of 5-12 years old. The younger children have higher scores and older children have lower scores. There is a clear correlation between the test and the IQ obtained from other intelligence scale tests.

(2) Diagnostic method

1 Webster's Intelligence Scale for Children (WISC-CR): for children aged 6 to 16 years.

2 China-Wei's Child Intelligence Scale (CWYCSI): for children aged 4-6 years.

3 Infant Developmental Scale (Gessell ScaleR) is suitable for children from 0 to 3 years old.

2. Adaptive behavior assessment

(1) Infant-Children's Social Life Ability Scale is applicable to children from 6 months to 13 years old 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 neonatal NBNA in the country through investigation and research, and its clinical development should be gradually carried out.

Mental retardation diagnosis

diagnosis method

First, according to IQ and adaptive behavior and age of onset, determine whether there is MR, and then further find the cause of MR.

In the process of diagnosis, the child's growth and development history should be collected in detail, and physical and neuropsychiatric examinations should be comprehensively conducted. The growth and development indicators of children of different ages at different developmental stages should be compared and compared with normal children of the same age to determine their intelligence level and adaptability. , making clinical judgments. At the same time, with the appropriate intelligence test method, the diagnosis can be made and the severity of MR can be determined.

1. Collection of medical history

(1) Family history: It is necessary to know whether parents are married to close relatives, and whether there are blind, dumb, epilepsy, cerebral palsy, congenital malformations, MR and mental illness in the family.

(2) History of maternal pregnancy: ask the mother if there is any viral infection, miscarriage, hemorrhage, injury, taking chemical drugs, exposure to poison, radiation, whether there is hypothyroidism, diabetes and severe malnutrition, and whether there are multiple births or amniotic fluid. Excessive, incomplete placental function, maternal and child blood type incompatibility.

(3) Birth history: Whether it is premature or expired, whether there is abnormal production mode, whether the birth weight is low birth weight, whether there is suffocation, birth injury, intracranial hemorrhage, severe jaundice and congenital malformation.

(4) History of growth and development: including neuropsychiatric episodes, such as the time when the big movements such as raising the head, sitting up, walking, etc., the use of fingers to detect the completion of fine movements such as small toys and daily necessities, shouting father and mother, listening to speech, etc. The developmental state of language function, as well as other intellectual behaviors such as feeding, dressing, and controlling bowel movements.

(5) Past and present disease history: whether there is craniocerebral trauma, hemorrhage, central nervous system infection, severe systemic infection, seizures, etc.

2. Physical examination

Physical examination

3. Developmental examination

Developmental examination

4. Neuropsychiatric examination

Neuropsychiatric examination

5. Laboratory inspection

Laboratory tests include blood, urine, brain, spinal fluid biochemical tests, cranial X-ray and CT examination, cerebral angiography, EEG, evoked potentials, audiometry, chromosome analysis, pituitary, thyroid, gonads, adrenal function tests, viruses (such as cytomegalovirus, rubella virus), protozoa (such as toxoplasma) and antibody testing. The relevant items should be selected according to the diagnostic needs.

6. Intelligence test and behavior judgment

Mild MR multi-use intelligence test, severe MR above the use of intelligence test methods are often difficult, must rely on the behavior rating scale, and the rating scale is not as reliable as the intelligence test for the identification of mild MR. Therefore, the two methods should be used together, and the results must be comprehensively analyzed.

Differential diagnosis

1. Children with autism Most children with autism have different levels of intelligence defects, but mainly have social interactions, damage to language communication, stereotypes and repetitive actions, and forced to adhere to the same way and other weird behaviors.

2. Children with schizophrenia mostly start after 7 or 8 years old. They have inconsistent thinking, delusions, hallucinations, and indifference. In addition to the recession, the general mental defects are not obvious.

3. Organic psychosis has infection, poisoning, trauma and other medical history or neurological signs. Although it is accompanied by intelligent defects, it is not as comprehensive as mental retardation, but has fewer obstacles in life skills.

The material in this site is intended to be of general informational use and is not intended to constitute medical advice, probable diagnosis, or recommended treatments.