Intellectual Development Disability is a condition of subnormal intellectual and social development. A mentally challenged person’s intelligence ranks significantly below average, and the social functioning of such a person is less competent than of other people of the same age and cultural group. Many mildly handicapped children are not recognized as handicapped until they start school and fail to learn well. Most of these youngsters are not at all unusual in appearance. On the other hand, some seriously handicapped youngsters are identified early in life because they are slow to sit up, walk or talk, or because they have physical handicaps.
In the past, doctors and social workers commonly advised parents to place their handicapped child in a custodial institution, but today, experts believe that all but the most seriously handicapped can benefit more by living in a community. Caring for the handicapped at home requires great patience and understanding. Many parents have difficulty adjusting to the fact that their child has below average mental ability. Counseling has helped many parents accept the situation and learn how to help their children.
Degrees of Mental Handicap
Mental ability can be measured by IQ- that is, a person’s score on an intelligence test. People of average intelligence score from 90 to 109 on such a test. An IQ of below 70 signifies one of our four degrees of mental schools. By the time the mildly handicapped reach their late teens, they may be able to do simple schoolwork. Many mildly handicapped adults can support themselves as unskilled or semiskilled workers.
Moderately handicapped people have IQs of 35 to 50. They can make little of no progress in such subject as reading, writing, and arithmetic. Most require special schools. They can learn to care for themselves and perform useful tasks at home or I sheltered workshops. Severely handicapped people have IQs of 20 to 35. They require training in language, personal hygiene and getting along with others. Severely handicapped individuals must be cared for throughout life.
Profoundly handicapped people have IQs below 20 and never advance beyond the mental age of a baby or toddler. Many need total care to survive, though they may learn to walk and to recognize familiar faces.
Causes
Mental handicap may result from many different factors. The normal development of a human being is so complex that almost anything that interferes with it may contribute to handicap.
Multiple causes
Many mentally challenged individuals seem to be handicapped by a combination of factors, no one of which by itself could have produced the handicap. Many mildly handicapped children, for example, come from families with little money, poor health, low educational achievement, poor nutrition and other disadvantages. Some parents are too discouraged or too overworked to provide a good learning environment for their children. Furthermore, many different genes contribute to intelligence, and a child may inherit an unlucky combination of many genes.
Single causes
In a small number of cases, a single cause accounts for most of the handicap. These causes have such overwhelming effects that normal development is impossible. Single cause may be genetic (inherited) or environmental. Genetic conditions causing mental handicap include the presence of an extra chromosome or an abnormal chromosomes are cellular chromosomes that contain the heredity controlling genes. Chromosomes are cellular structures that contain the heredity controlling fragile-X syndrome involves an abnormality of the X chromosome, one of the chromosomes that determines a person’s sex. This condition affects mostly males. More rarely, handicap may be caused by the absence of a necessary chromosome. Handicap may also result from the effects of a dominant gene or a pair of recessive genes that interfere with normal growth or metabolism. Phenylketonuria (PKU), a condition in which a person cannot pair of recessive genes. PKU causes brain damage if the diet is not controlled.
Environmental causes of mental handicap may occur before, during, or after birth. A child may be handicapped if the mother contracts such a disease as rubella German measles or syphilis during pregnancy. The mental development of a child may also be affected by other factors concerning the mother’s health during her youth or while she is pregnant. These factors include her nutrition, her age and general health, and her use of drugs. Events at birth can also cause handicap. They include premature birth, injury during prolonged high fever, swallowing concentrated poisonous substances, or breathing such substances from polluted air.
Prevention
Proper care of the mother before and during pregnancy can prevent many cases of mental handicap. Proper delivery and care of sick or premature infants also help reduce the number of cases. Damage resulting from PKU and a few other disorders can be controlled after birth by a special diet or treatment with drugs.
Doctors can identify through tests some couples for whom having children would involve child. Other tests can reveal certain kinds of genetic conditions in an unborn baby. The parents may then decide to discontinue the pregnancy.
Handicap produced by multiple causes is more difficult to prevent. Many experts believe the number of such cases could best be reduced by improving the living conditions, health, education and economic level of the poor.
Treatment
The mentally challenged cannot be “cured." But in most cases a great deal can be done to help their intellectual and social development. Much of this treatment consists of appropriate education or training. In many countries, it is the legal right of every handicapped person to function to the best of his or his or her ability. In some cases, training can begin in infancy. It may continue until the individual is well established in an adult role.
As handicapped children grow up, their education tends to centre more and more on the skills they will need as adults. Many mildly handicapped adults become good workers and good citizens. Mildly handicapped adults who cannot hold a job, and moderately to severely handicapped adults may work in sheltered workshops- a centre that employs the handicapped. These men and woman live with their families or in homes for the handicapped in the community, with qualified careers. Only the most severely handicapped, who require total care, are likely to live permanently in residential facilities without doing any productive work.
