Home » Diseases and Conditions » Mental Retardation

Mental Retardation

Written by Dr.Mary

What is Mental Retardation?

Mental retardation is a cognitive disability that is termed as sub average intelligence and impaired mental and adaptive functioning. This intellectual disability may start to arise and progress to those aged below 18 years. This neurodevelopmental disability is common to pediatric patients. As regarding with the term mental retardation, social stigma has been quite the problem of those affected and of the parents, close relatives of the mentally challenged individual. The term “mentally retarded” is placed to avoiding of its use as for intellectually disabled is a much more suitable terminology of the mental condition.

According to studies, mental retardation is manifested among 3% of children and an approximately 10% of children has some learning impairment, but shouldn’t be compared with MR/ID. In order to diagnose such condition, the use f the DSM – IV is essential in the process. It has been noted that one can be diagnosed of such condition if the child has an intelligence deficit of at least 2 standard deviations below the mean IQ. A mean score of 100 of an IQ test is the standard average of an individual. In case of mental retardation, an intelligence quotient score of 70-75 and below is mentally retarded. The functional skills of a person affected of intellectually disabled are skills of communication, self-care, home living and daily living, social and interpersonal skills, use of community resources, self-directions, academic skills, work, leisure, health and safety. In general, the domains affected of mental retardation are conceptual skills, social skills and practical skills. In terms of epidemiological reports, the frequency of MR of all degrees ranges from 1.6 to 3% of all population in the US. A particular race is not associated with this mental disability, as well in gender.

Mental retardation does not necessarily present death to the affected, however cases of severe and profound mental retardation has provided a decreased life expectancy to the affected for complications may arise such as neurologic disorders. Respiratory complications are also presented in some cases of profound ID. Some psychiatric conditions are associated with this condition and these include ADHD (attention deficit/hyperactivity disorder), self-injury and mood disorders.

Mental Retardation Types

The types of mental retardation are basically the same with the levels of mental retardation. The condition is classified according to these:

  • Mild – The person is educable.
  • Moderate – The person can be trained but cannot learn academic subjects at school.
  • Severe – Confinement may be necessary.

Mental Retardation Causes

The causes of this condition would generally conclude to genetics. There is some alteration in the DNA structure of the affected. Here are the following prenatal conditions associated with mental retardation:

Genetic irregularities

Trisomy 21 or Down syndrome

Those who are accounted to have Down syndrome have mental retardation. An approximate 1 per 800 live births have Down syndrome. About 25 to 50% of all cases have severe mental retardation. The condition is referred as trisomy 21 for the chromosome 21 of the affected is increased in fashion.

Fragile X syndrome

The prevalence of this disorder is approximately 1 in 3500 males. According to studies, mental retardation from fragile X patients is accounted about 5.9% of cases in males while only 0.3% in females.

Contagious gene deletion syndromes

This is a less common cause of mental retardation.

Birth problems

Premature birth may be a cause of this condition as the brain is not well developed at this time.

Environmental factors

  • Fetal alcohol syndrome and fetal alcohol effect – Alcohol has a great influence in teratogenic effects. Mental retardation is one of the common adverse effects of alcohol abuse while a woman is pregnant.
  • Congenital hypothyroidism – This neurologic syndrome can result to severe thyroid hormone deficiency during the fetal period. As the infant is growing; he or she may have a compromised speech resulting to mutism-deaf, moderate to severe MR, spasticity and strabismus.
  • Congenital rubella – Pregnant mothers who have contracted rubella may compromise the health of the child.
  • Meningitis, neurodegenerative disorders and shaken baby syndrome are said to be possible causes of mental retardation.

Mental Retardation Characteristics

The presenting characteristic of mental retardation truly depends on the type and level of intellectual incapacity. A person’s developmental progress truly depends on the etiology of the condition and its level. Here are the following characteristic presentations of mental retardation:


Language delay is one of the first signs of MR/ID. Speech as in expression is altered and the receptive language or the response of a mentally retarded patient is altered. Understanding is not entirely attained as to taking response to a communication.

Fine motor

There is delay in the motor adaptation. Significant delay is noted as to areas of self-care activities. These include self-feeding, toileting and dressing.


Cognitive delay is noted as there is difficulty in memory, problem-solving and logical reasoning.


Communication delay is noted. Social interaction is found ineffective for the affected may present lack of interest in age-appropriate activities and play.

Gross motor


Motor development is said to be altered. The child or person may have difficulty in their fine motor and adaptive skills. Clumsiness is noted among patients with MR.


Behavioral disturbances are noted as they have difficulty in controlling oneself. There is deviance from the normal temperament of behavior. Aggression, self-injury, inattention and hyperactivity are commonly the behaviors observed to patients.


In some cases, neurologic abnormalities are associated with MR. This would include seizure problems, microcephaly, macrocephaly, prematurity and congenital anomalies.

Levels of Mental Retardation

MR/ID is categorized according to the disability:

Mild retardation

An IQ mean score of 50-55 to 70 would indicate for a mild retarded case. The education level that a person is capable of attaining is only about the 6th grade. Mild retardation is also referred as educable.

Moderate retardation

An IQ mean score of 35-40 to 50-55 is moderately retarded. The person affected is capable of attaining 2nd grade level of education. While the person needs supervision. It is also referred as imbecile.

Severe retardation

An IQ mean of 20-35 to 35-40 is categorized as severe. The person affected may learn words, and can adapt to elementary self-care skills and activities. There is need of close supervision in this case of retardation. This level of mental retardation is referred as moron.


An IQ mean of <20 – 25 is profound mental retardation. The child or person has little self-care skills that one needs constant aid and supervision. This condition affects about a small population of MR/ID cases. Profound mental retardation is also referred as “idiot”. This has the greatest degree of intellectual disability.

Severe Mental Retardation

This level of mental retardation needs intensive support and supervision for the rest of his or her life. The child may still be capable of learning activities of daily living but still needs assistance in most times. It is recommended that the person with severe mental retardation has an attendant to avoid self-destructiveness, and injury infliction to oneself.

Mild Mental Retardation

Mild mental retardation is termed to have a cognitive age of about eight to twelve years. Those with mild retardation has a learning disability but is only limited. But the person affected can learn self-care activities and practical skills. They are even capable of living and reaching adulthood and even gain employment.

Mental Retardation in Children

Mental retardation begins in childhood or before the age of 18. In most cases, this condition would persist in the adult life. Mental retardation in childhood does not mean that they cannot attain the developmental milestones of life. Normally, they attain the important milestones in life such as walking and talking. But as the symptoms of mental retardation presents and starts to appear, the child can be diagnosed with the difficulties of social, communication and academic skills.

Mental Retardation Facts

Social stigma should not be placed on people with mental retardation. This has been prevalent but is tried to be lessened by social groups who support those people with intellectual disabilities. A person who is mentally retarded needs love, care and support that one has to offer. One should always put in mind that this condition is not a disease but a mental illness.

Those affected of mental retardation needs more time to adjust compared with people who are intellectually gifted. They may have a slower grasp of ideas in life, and has trouble in adjusting cognitively. Assistance is a must and we need to approach them in a manner that is acceptable to the society.

We need not to pressure those with ID for this can only make them wary of things. Assistance and understanding is a must when one is interacting with a mentally retarded person.


The primary treatment for a person with mental retardation is to develop his or her potential in life. Assist the client in attaining his greatest potential. Providing special education and training should start in an early age. Evaluation of the child’s condition is a must before anything else so that he or she shall receive the recommended assistance that he needs. There is no specific medication for this condition. A health care provider should always have a standing goal of assisting the person with ID to attain his fullest capability.

Leave a Reply

Recent Posts