Definiton of Mental Retardation,Description, and Treatment

Mental retardation: A term used when a person has certain limitations in mental functioning and in skills such as communicating, taking care of him or herself, and social skills. These limitations will cause a child to learn and develop more slowly than a typical child.

Children with mental retardation may take longer to learn to speak, walk, and take care of their personal needs such as dressing or eating. They are likely to have trouble learning in school. They will learn, but it will take them longer. There may be some things they cannot learn. As many as 3 out of every 100 people have mental retardation. In fact, 1 out of every 10 children who need special education has some form of mental retardation.

There are many causes of mental retardation. The most common causes are:
Genetic conditions -- Abnormalities of chromosomes and genes. Examples of genetic conditions are Down syndrome (trisomy 21), fragile X syndrome, and phenylketonuria (PKU).

Problems during pregnancy -- When the baby does not develop normally inside the mother. For example, a woman who drinks alcohol or gets an infection like rubella during pregnancy may have a baby with mental retardation.

Perinatal problems -- Problems during labor and birth, such as not getting enough oxygen.

Health problems -- Diseases like whooping cough, the measles, or meningitis. Mental retardation can also be caused by extreme malnutrition or being exposed to poisons like lead or mercury.

The diagnosis of mental retardation is made by looking at two main things. These are (1) the ability of a person's brain to learn, think, solve problems, and make sense of the world (intellectual functioning or IQ); and (2) whether the person has the skills he or she needs to live independently (called adaptive behavior, or adaptive functioning).

Description
Mental retardation occurs in 2.5-3% of the general population. About 6-7.5 million mentally retarded individuals live in the United States alone. Mental retardation begins in childhood or adolescence before the age of 18. In most cases, it persists throughout adulthood.

A diagnosis of mental retardation is made if an individual has an intellectual functioning level well below average and significant limitations in two or more adaptive skill areas. Intellectual functioning level is defined by standardized tests that measure the ability to reason in terms of mental age (intelligence quotient or IQ).

Mental retardation is defined as IQ score below 70-75. Adaptive skills are the skills needed for daily life. Such skills include the ability to produce and understand language (communication); home-living skills; use of community resources; health, safety, leisure, self-care, and social skills; self-direction; functional academic skills (reading, writing, and arithmetic); and work skills.

In general, mentally retarded children reach developmental milestones such as walking and talking much later than the general population. Symptoms of mental retardation may appear at birth or later in childhood.

Time of onset depends on the suspected cause of the disability. Some cases of mild mental retardation are not diagnosed before the child enters preschool. These children typically have difficulties with social, communication, and functional academic skills.

Children who have a neurological disorder or illness such as encephalitis or meningitis may suddenly show signs of cognitive impairment and adaptive difficulties.
Mental retardation varies in severity. The Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) is the diagnostic standard for mental healthcare professionals in the United States.

The DSM-IV classifies four different degrees of mental retardation: mild, moderate, severe, and profound. These categories are based on the functioning level of the individual.

Mild mental retardation
Approximately 85% of the mentally retarded population is in the mildly retarded category. Their IQ score ranges from 50-75, and they can often acquire academic skills up to the 6th grade level. They can become fairly self-sufficient and in some cases live independently, with community and social support.

Moderate mental retardation
About 10% of the mentally retarded population is considered moderately retarded. Moderately retarded individuals have IQ scores ranging from 35-55. They can carry out work and self-care tasks with moderate supervision. They typically acquire communication skills in childhood and are able to live and function successfully within the community in a supervised environment such as a group home.

Severe mental retardation
About 3-4% of the mentally retarded population is severely retarded. Severely retarded individuals have IQ scores of 20-40. They may master very basic self-care skills and some communication skills. Many severely retarded individuals are able to live in a group home.

Profound mental retardation
Only 1-2% of the mentally retarded population is classified as profoundly retarded. Profoundly retarded individuals have IQ scores under 20-25. They may be able to develop basic self-care and communication skills with appropriate support and training. Their retardation is often caused by an accompanying neurological disorder. The profoundly retarded need a high level of structure and supervision.

The American Association on Mental Retardation (AAMR) has developed another widely accepted diagnostic classification system for mental retardation. The AAMR classification system focuses on the capabilities of the retarded individual rather than on the limitations.

The categories describe the level of support required. They are: intermittent support, limited support, extensive support, and pervasive support. To some extent, the AAMR classification mirrors the DSM-IV classification. Intermittent support, for example, is support needed only occasionally, perhaps during times of stress or crisis.

It is the type of support typically required for most mildly retarded individuals. At the other end of the spectrum, pervasive support, or life-long, daily support for most adaptive areas, would be required for profoundly retarded individuals.

Causes and symptoms
Low IQ scores and limitations in adaptive skills are the hallmarks of mental retardation. Aggression, self-injury, and mood disorders are sometimes associated with the disability. The severity of the symptoms and the age at which they first appear depend on the cause.

Children who are mentally retarded reach developmental milestones significantly later than expected, if at all. If retardation is caused by chromosomal or other genetic disorders, it is often apparent from infancy.

If retardation is caused by childhood illnesses or injuries, learning and adaptive skills that were once easy may suddenly become difficult or impossible to master.

In about 35% of cases, the cause of mental retardation cannot be found. Biological and environmental factors that can cause mental retardation include:

Intellectual functioning, or IQ, is usually measured by an IQ test. The average IQ score is, by definition, 100. People scoring below 70 to 75 on the IQ test are considered to have mental retardation. To measure adaptive behavior, professionals look at what a child can do in comparison to other children of his or her age.

Certain skills are important to adaptive behavior. These are daily living skills (such as getting dressed, going to the bathroom, and feeding one's self), communication skills (such as understanding what is said and being able to answer) and social skills (interacting with peers, family members, adults, and others).

Treatment
Federal legislation entitles mentally retarded children to free testing and appropriate, individualized education and skills training within the school system from ages three to 21. For children under the age of three, many states have established early intervention programs that assess, recommend, and begin treatment programs.

Many day schools are available to help train retarded children in basic skills such as bathing and feeding themselves. Extracurricular activities and social programs are also important in helping retarded children and adolescents gain self-esteem.

Training in independent living and job skills is often begun in early adulthood. The level of training depends on the degree of retardation. Mildly retarded individuals can often acquire the skills needed to live independently and hold an outside job. Moderate to profoundly retarded individuals usually require supervised community living.

Family therapy can help relatives of the mentally retarded develop coping skills. It can also help parents deal with feelings of guilt or anger. A supportive, warm home environment is essential to help the mentally retarded reach their full potential. However, as of 2004, there is no cure for mental retardation.

A promising but controversial treatment for mental retardation involves stem cell research. In the early 2000s scientists are exploring the potential of adult stem cells in treating mental retardation. They have transplanted bone marrow cells into living embryos in the uteri of animals to approach congenital diseases, birth defects, and mental retardation.

Stem cells are primitive cells that are capable of forming diverse types of tissue. Because of this remarkable quality, human stem cells hold huge promise for the development of therapies to regenerate damaged organs and heal people who are suffering from terrible diseases.
Embryonic stem cells are derived from human embryos.

Their use is controversial because such stem cells cannot be used in research without destroying the living embryo. Other sources of stem cells are available, however, and can be harvested from umbilical cord blood as well as from fat, bone marrow, and other adult tissue without harm to the donor. An enormous amount of research involving adult stem cells is going on as of 2004 in laboratories in the United States.

Prognosis
Individuals with mild to moderate mental retardation are frequently able to achieve some self-sufficiency and to lead happy and fulfilling lives. To reach these goals, they need appropriate and consistent educational, community, social, family, and vocational supports. The outlook is less promising for those with severe to profound retardation.

Studies have shown that these individuals have a shortened life expectancy. The diseases that are usually associated with severe retardation may cause the shorter life span. People with Down syndrome develop in later life the brain changes that characterize Alzheimer's disease and may develop the clinical symptoms of this disease as well.

Prevention
Immunization against diseases such as measles and Hib prevents many of the illnesses that can cause mental retardation. In addition, all children should undergo routine developmental screening as part of their pediatric care. Screening is particularly critical for those children who may be neglected or undernourished or may live in disease-producing conditions.

Newborn screening and immediate treatment for PKU and hyperthyroidism can usually catch these disorders early enough to prevent retardation.

Good prenatal care can also help prevent retardation. Pregnant women should be educated about the risks of drinking and the need to maintain good nutrition during pregnancy. Tests such as amniocentesis and ultrasonography can determine whether a fetus is developing normally in the womb.