Screening of early intellectual development

The incidence of mental retardation is based on the above discussion, and the incidence of mental retardation depends on the definition, diagnosis method and research population. According to the classic definition, statistics show that 2.5% people in the population suffer from mental retardation, while the other 2.5% people have superhuman IQ (figure 16. 1). Among people with mental retardation, 85% have IQ lower than 2 ~ 3 standard deviations of the average, that is, within the range of mental retardation that requires intermittent nursing. If some people get low scores in the IQ test because of cultural and social factors, they will be excluded from the "mild" mental retardation, then the incidence just predicted will be reduced by half, about 0.8% and 1.2% (McLaren & Bryson, 1987). No matter what the incidence rate is, it reaches its peak at the age of 10 ~ 14, and it is found that mentally retarded children who need intermittent nursing are diagnosed later than those with mental retardation. Since the 1940s, the incidence of mental retardation requiring extensive nursing has not changed. This may be a natural balance between the improvement of medical level and the emergence of new diseases. For example, the mortality rate of premature infants with weight1500 ~ 2,500 g decreased significantly, and the survival rate of some smaller premature infants decreased significantly, some of which were below 1000g, and the incidence of these premature infants was relatively high (see Chapter 7) (Wolke, Ratschi ki, Ohrt et al. 1994) prenatal diagnosis reduces the birth rate of children with down syndrome, neonatal screening and early diet therapy reduce mental retardation caused by phenyl. These two preventive measures help to balance, because prenatal drug abuse (including alcohol) and congenital human immunodeficiency virus infection (see Chapters 8 and 9) increase the incidence. In addition, many mentally retarded patients who need extensive care are caused by hereditary or congenital brain malformations, which cannot be found or prevented in advance. Generally speaking, if there is already a mentally retarded child who needs extensive care and the cause is unclear, the probability of mental retardation in this family is 3% ~ 9% (Costeff & Weller,1998; Lonhiala, 1995). If a child in the family suffers from mental retardation due to neonatal meningitis, the risk of mental retardation will increase significantly. However, if the mother once had a child with fetal alcohol syndrome (FAS), the next child may have 30% ~ 50% if she does not give up drinking. In Down syndrome, the chances of the next child having the same situation again may be different. If it is 2 1- trisomy, the probability is1%; If it is a balanced translocation, the probability is greater than 10% (see Chapter 1) (Mikkelsen, Ponlsen and Tommerup,1989; Wolff, Back, Arleth et al., 1989). If the cause of mental retardation is genetic abnormality, such as neurofibromatosis (autosomal dominant inheritance), Huler syndrome (autosomal recessive inheritance) or fragile X syndrome (X chromosome related inheritance), the risk of the next child varies from 0 to 50%, depending on the type of genetic abnormality. Children with mental retardation who only need intermittent care are usually just mentally retarded, but children with mental retardation who need extensive care often have other dysfunction, which further limits their adaptability and causes other adverse reactions. Complication disorder is related to the severity of mental retardation (Kiely,1987; Pollack,1993; Stef Egger, Hagburg and Kellerman,1995; Steffe urg, Hagberg, Viggedal et al., 1995). These complications include cerebral palsy, visual impairment, convulsion, communication disorder, feeding difficulty, psychological disorder and attention deficit/hyperactivity disorder (ADHD) (table 16.3). More than half of the mentally retarded children who need extensive care and one quarter of the children who need intermittent care have sensory impairment, among which visual impairment, especially strabismus and ametropia, is the most common. Language barriers (more than other cognitive barriers) are also common. About 20% children who need extensive care will have cerebral palsy, which may be related to feeding difficulties or dysplasia. At the same time, 20% of mentally retarded children have convulsions. In addition, about half of children may have psychological disorders (such as severe developmental disorders) and behavioral disorders (such as self-injury behaviors). While considering treatment, we also need to diagnose and treat these complications. Table 16.3 The proportion of children with mental retardation comes from: Kiely. M( 1987)。 Incidence of mental retardation. Epidemiological review shows that 9 194 combined disorder makes it difficult to distinguish mental retardation from other developmental disorders. However, some points that are helpful for identification still exist. In the aspect of pure intellectual development, the verbal and non-verbal thinking ability is obviously backward, while the motor function is relatively good. On the contrary, in children with cerebral palsy, dyskinesia is more prominent than cognitive impairment. Children with communication disabilities, language expression and acceptance ability obviously lag behind the motor and non-verbal thinking ability. Social dysfunction, abnormal behavior and cognitive (especially communication) obstacles are more obvious in children with severe developmental disabilities. In some cases, multiple assessments can be made to confirm the primary developmental disorder. Etiology of mental retardation Epidemiological data of mental retardation show that there are two overlapping groups. Most patients with mental retardation who need intermittent nursing have low social and economic status and have not received a good educational environment; The incidence of patients who need extensive care is mostly related to biological reasons. There is often a * * * interaction between nature and nutrition. For example, a child may initially have biological damage (such as intrauterine growth retardation), which is usually combined with environmental factors (such as malnutrition and mother's negligence). Mothers without higher education are four times more likely to give birth to children who need intermittent care than mothers with higher education (Cap Tue & Accaro,1996; Drews, Yeargin-Allso, Decoufle et al., 1995) The reasons for this situation are not very clear, but it is likely that there are genetic factors (that is, children have cognitive impairment) and socio-economic factors (that is, poverty, negligence and malnutrition). African children are twice as likely as Soviet children to suffer from mental retardation requiring intermittent care, and at least half of them are caused by poverty or other social unfavorable factors (Yeargin-Allo, Decoufle et al., 1995). The interaction between nature and nutrition is also one of the reasons. For example, early treatment of high-risk children can improve their cognitive ability. Two-thirds of mental retardation requiring extensive care can be diagnosed as biological reasons. Among them, the most common diagnoses are fragile X syndrome (see chapter 18), Down syndrome (see chapter 17) and fetal alcohol syndrome (FAS), which are almost13 of mental retardation cases requiring extensive nursing (Stanley16.4). Table 16.4 diagnosable causes of mental retardation requiring extensive care (%) One of the ways to distinguish the biological causes of mental retardation is according to their different onset times in the development process (Crocker, 1989). Generally speaking, the earlier the problem appears, the more serious the consequences will be. Chromosome diseases (such as Down syndrome) and hereditary malformations (such as Deron syndrome) will affect the development of early embryos, which is the most common (accounting for half of the diagnosable causes) and the most serious (see chapter 1). Accidents in the first trimester and the third trimester account for 10% of cases, including drug-induced (such as FAS, that is, fetal alcohol syndrome), infectious (such as cytomegalovirus infection) and other problems during pregnancy (such as intrauterine growth retardation) (see Chapter 4). Mental retardation caused by late pregnancy and perinatal complications accounts for less than 10% of cases requiring extensive care. Another 10% is due to single gene defect (such as congenital metabolic disorder) (see chapter 19). Another 5% is caused by perinatal brain injury, mostly because of brain infection or trauma. Contrary to mental retardation requiring extensive care, the etiology of mental retardation requiring intermittent care is currently less than 20%(Akeon, 1986). The most common biological causes are perinatal injury, drug abuse (especially alcohol) and sex chromosome abnormality (Matilainen, Airaksinen, Mononen et al., 1995). No single clinical diagnosis and examination method can detect all the causes of mental retardation. Therefore, the basis of diagnosis and examination is medical history and physical examination (Majnemer & Shevell, 1995). For example, a child with a special face and various congenital malformations should have a chromosome examination. Children with autism and/or family history of mental retardation should be examined for fragile X syndrome. If the child has progressive neurological dysfunction, multiple metabolic tests should be performed, if the child has convulsion-like seizures, EEG should be performed, and if the child has head malformation or asymmetric neurological abnormalities, neuroimaging should be performed (Levy & Hyman, 1993). Although the above are the most common reasons for diagnostic examination, it is now believed that some children may have biological reasons if they have obvious signs or abnormal nervous system examination. It is reported that 6% of mental retardation of unknown cause is caused by chromosome abnormality, and further examination is needed to clarify the cause (Flint, Wilkie, Buckle et al., 1995). Some children have no obvious abnormal signs, and ordinary examination may not rule out abnormalities (for example, neuroimaging examination is not sensitive to detecting abnormalities in the developing brain) (Huttenlocher, 199 1). The depth of the doctor's investigation of the child's etiology should depend on the following questions: First, the degree of mental retardation? For children who need intermittent care, it is less likely to find the cause. Second, is there a specific diagnosis method? If the medical history, family history or physical examination all suggest a specific cause, it is easier to diagnose; On the contrary, without these indicators, it is difficult to choose a test to diagnose. Third, do parents intend to have another child? If so, it is necessary to find the cause so as to make prenatal diagnosis or make a treatment plan. Finally, what are the parents' requirements? Some parents of children are not interested in the cause and focus on treatment; Other parents emphasize the definition of the cause, and they don't agree to the treatment if they can't find the cause. We should respect all opinions, but at the same time, we should give parents reasonable guidance. Infant development test ID is used to evaluate the fine movements, rough movements, language, ability to understand problems and behavior of children aged 1 month to 3.5 years old. The evaluation results are MDI (intelligence development score) and PDI (psychomotor development index score). The infant test also includes Bater and Mullen's Early Language Scale. Repeated cognitive ability tests for normal-developing babies will have very different results. Therefore, the accuracy of the prediction is relatively poor, and the situation did not improve until 10 years old. The predictive value of infant tests is more limited, because their tests are limited to topics that are not expressed in words, and language topics are the best for future IQ scores (Bayley, 1958). These tests can distinguish between mentally retarded children who need extensive care and normal infants, but it is difficult to distinguish between normal infants and mentally retarded children who need intermittent care (Maisto & German, 1986). But generally speaking, in terms of cognitive ability, the variation of mentally retarded children is smaller than that of normal infants, which is helpful to enhance the accuracy of prediction. Infant Intelligence Test Among many psychological tests used for infants over 18 months old, one is Stanford -Bi 163.com Intelligence Scale (Terman & Merrill, 1985). Including 15 to evaluate intelligence from four aspects: language function, abstract thinking function, quantitative concept and short-term memory. This enables the evaluator to carefully analyze the advantages and disadvantages of the child. However, this scale is long and not easy to use, so it is not the first choice. And it is not enough to diagnose mental retardation (Wodrich, 1997). Wechsler scale is the most commonly used psychological test for children over 3 years old. Wechsler Preschool Intelligence Scale (W I-R) (Wechsler, 1989) was revised in 1989, and was used for children aged 3-7 years. Wechsler intelligence scale for children (WISC-Ⅲ, 199 1 revised edition) is used for children with intelligence over 6 years old. Both scales have many parts to evaluate language and operational ability. Although the average scores of children with mental retardation are low, some of them can score within the normal range in one or two aspects. Generally speaking, Stanford -Bi 163.com and Wechsler Scale are more accurate in predicting the IQ of school-age children in adulthood. But the evaluator must ensure that the situation that leads to false low IQ is not confused with the final result of the test. Such as dyskinesia, communication disorder, sensory disorder, using languages other than English, extremely low birth weight or poor social and cultural conditions, will make some intelligence tests invalid and need to be corrected by other tests and explained in detail. Adaptive function test According to DSM-IV's definition of mental retardation, besides intelligence test, adaptive function should also be evaluated. The most commonly used adaptive behavior test is VA, which includes the evaluation of parents' and/or nanny/teacher's semi-structured conversation to adapt to four aspects of behavior: communication, daily life skills, social interaction and motor skills. There are three kinds of questionnaires, 244 ~ 577 questions. Other tests of adaptive behavior include Woodcock-John Independent Behavior Scale (Bruinicks, Woodcock, Weatherman et al., 1996) and Adaptive Behavior Scale of the American Association for Mental Retardation (A )(Wodrich, 1997). Generally speaking (but not absolutely), the scores in intelligence and adaptation scale are related (Bloom & Zelko, 1994). But adjustment disorder's therapeutic effect is better than IQ. The most effective treatment for children with mental retardation is training in all aspects of children's life-including education, social and recreational activities; Behavioral problems and merger obstacles (Colozzi & Pollow, 1984). You also need to discuss with your child's parents, brothers and sisters. Education service education is the most important training for the treatment of mentally retarded children. Good results depend on the joint efforts of teachers and students. Educational plans must meet the needs of children and be formulated according to their strengths and weaknesses. The level of a child's development, the degree of care he or she needs, and independent goals provide the basis for making an education plan. Generally speaking, children with mental retardation who need intermittent nursing need to learn technical and professional skills in order to live independently in the future, while children with mental retardation who need partial and extensive nursing need to learn "survival" skills, which are useful in nursing work environment and changing living environment. Besides education, children's social and recreational needs should also be paid attention to (Dattilo & Schleien, 1994). In an ideal world, mentally retarded children participate in recreational activities as much as they do. In reality, although children will not be excluded from participating in activities, young patients often do not have the opportunity to engage in appropriate social interaction, and they are not prominent in extracurricular sports activities. In fact, participation in sports activities should be encouraged, because it is very beneficial, including regulating weight, coordinating physical development, promoting cardiovascular activities and improving self-image (Eichstaedt & Laray, 1992). Social activities are equally important. This includes dancing, traveling, dating and other normal social and entertainment activities. In order to promote children's socialization, some obvious behavior problems must be pointed out (Walker, 1993). Although most children with mental retardation have no behavioral disorders, the incidence of behavioral disorders in this group is higher than that of children with normal development (Fraser & Rao, 199 1). Behavioral problems may be related to parents' high expectations, physical problems and family environment. Behavioral problems can be manifested in the hope of getting others' attention or avoiding setbacks. When evaluating this behavior, we must consider whether it is reasonable for the child's age, and sometimes it does not need special treatment. If you need treatment, you can consider changing the environment, such as a more suitable classroom environment, or help improve behavior problems. For some children, behavior control (Chapter 30) or medication is sometimes necessary. Drug therapy is not very effective in treating the main symptoms of mental retardation; No drugs have been found to improve intelligence. However, medication is very helpful to treat some behavioral and mental problems. These drugs are used for certain behaviors, including ADHD (such as phenylpiperidine methyl acetate [ritalin]); Self-injury behavior (such as haloperidol [Amdo]); Aggressive behavior (such as carbamazepine [Delido]); Depression (such as fluoxetine [Prozac]) (Oman, 1993). These drugs will be discussed in detail in chapters 20 and 22. Short-term trials should be conducted before long-term use of any psychotropic drugs for treatment. The child's teacher had better agree to be an observer and adopt the blind method, that is, the teacher doesn't know how to deal with it, but makes an observation record of the child's attention, behavior and activity level (Coward & Wells, 1986). Even if drug therapy is proved to be effective, it should be re-tested at least once a year to decide whether it is necessary to continue drug therapy. Treatment of combined disorders If there is a combined disorder-cerebral palsy; Visual and hearing impairment; Seizure; Speech disorder; Autism and other language and behavior disorders-these disorders must be treated. This requires continuous physical therapy, professional therapy, speech therapy, adaptive functional equipment, glasses, hearing AIDS, antiepileptic drugs and so on. If not diagnosed and treated in time, these problems will be hidden, leading to difficulties in children's study, family and daily life. Family Counseling Many families can quickly adapt to their children's mental retardation, but some families are not. Family-related factors include marriage stability, parents' age, parents' self-esteem, number of brothers and sisters, socio-economic status, severity of obstacles, parents' expectation and acceptance of diagnosis, support from family members, participation in social activities and care for children. Family counseling is also a part of family holistic treatment for children with mental retardation (see Chapter 34). Regular reassessment Although mental retardation is considered as a chronic disease, after a period of time, the requirements of children and their parents will change. When children grow up, parents should know more, re-evaluate their goals and adjust their plans. Regular review includes the child's physical condition and various abilities at home, school and other environments. Others must take formal psychological or educational tests. Although 1975's Educational Behavior of All Disabled Children (PL94- 142) stipulates that it should be reassessed every three years. However, if the child achieves the expected therapeutic effect or the child is transferred from one treatment institution to another, it should be re-evaluated. Re-evaluation is also necessary, especially during adolescence or transition to adulthood, because the treatment given during these periods will be reduced appropriately. The prognosis of children with mental retardation depends on the etiology, severity, combined developmental disorders and the role of family. Many adults with mental retardation who need intermittent nursing are only equivalent to the fifth grade education (that is, functional illiteracy), but they can be independent in economic and social functions in the future. They may need regular supervision, especially in terms of social and economic pressures. Many people can successfully get married and live in society in an independent or supervised environment (American Psychological Association). Life expectancy is not affected. For mentally retarded children who need partial care, the goal of education is to strengthen their adaptability, "survival" skills and working ability, so that they can survive better in the adult world. They may reach the education level of the second grade. It is in their best interest if they can find a job that can take proper care of them like their peers. The idea of treating a job with proper caution conflicts with the idea that you must learn the "necessary" skills to adapt to the job. The latter believes that patients should learn to do specific work in the working environment under the training of coaches. This view ignores the necessity of accumulating experience in work and the gradual adaptation of many mentally retarded patients to work in communication. The curative effect study also shows that the former has better curative effect. People with mental retardation who need partial care usually live at home or under supervision. Most patients with Down syndrome fall into this category. The mentally retarded who need extensive or close care are still at the level of preschool children's ability. They may be able to complete simple tasks in a closely supervised work environment. However, these patients often suffer from other diseases, such as cerebral palsy and sensory disturbance, which further affects their adaptive function. Most people with mental retardation at this level live in the community and live with their parents. However, if some patients have serious clinical manifestations, behavioral disorders or family breakdown, they have to live in other environments, such as nursing homes, frequent residence changes, group dormitories, nursing homes, boarding schools and charities. The life expectancy of patients with mental retardation who need extensive or close care is shortened (figure 16.2)(Eyman, Gro man, Chanay et al., 1990). The development of summarization is a gradual process, which is related to the maturity of the central nervous system. If you have mental retardation, your development will be affected, and your intelligence and adaptive function will be hindered. In most cases of mental retardation requiring intermittent nursing, the underlying causes are still unclear. However, 2/3 patients with mental retardation have definite causes and need extensive care. Although most mentally retarded children who need intermittent nursing can be independent economically and socially, early diagnosis and timely treatment are helpful to promote children's development and enhance their functions.