What is mental retardation?

Mental retardation negatively affects various areas of life; like academics, work life, the inability to form or maintain social relations as well in daily life functioning like taking care of one self and ones hygiene. It is also called as intellectual disability, intellectual development disorder, general learning disability as well as mental retardation. More recently people with mental retardation are called mentally challenged. It is generalized neurological development disorder.

Individuals with mental retardation would score low in intelligence tests. It is considered to be more of a disability than a disease. It is also called Intellectual disability (ID), intellectual development disorder (IDD) or general learning disability. Mental retardation can cause developmental disability i.e. delayed development or difficulties in various areas of life (more than one area of life), especially in language, mobility, learning, self-help, and independent living.

How is mental retardation diagnosed?

To understand mental retardation we need to have an idea of I.Q. (Intelligence Quotient). I.Q. is a standardised procedure for comparing intelligence of individuals. There are various tests that would give us a fair idea about the I.Q. of an individual, i.e. how intelligent an individual is. Individuals scoring in between 70 to 80 on an intelligence test are said to be on the border line of mental retardation, individuals scoring below 70 would be diagnosed with having mental retardation however the severity of mental retardation would depend upon the score on an intelligence test. The chart below would give a clear picture of the scores and the levels of intelligence or mental retardation

I.Q range Classification of intelligence
140 + Genius
130 – 140 Gifted or very superior
120 – 130 Superior intelligence
110 – 119 Above average intelligence
90 – 109 Average intelligence
80 – 89 Below average or dull normal intelligence
70 – 80 Border line intelligence
50 – 70 Mild retardation
49 – 35 Moderate retardation
20 – 34 Severe retardation
20 Profound retardation

What are the causes of mental retardation?

Causes of mental retardation can be prenatal i.e. before birth conditions, perinatal i.e. during birth conditions and postnatal i.e. after birth conditions.

  1. Genetic causes – abnormal genes can be inherited from parents or there can be errors in the combinations of genes or chromosomes. To name a few Down syndrome, Klinefelter’s syndrome, Fragile X syndrome (common among boys), neurofibromatosis, congenital hypothyroidism, Williams syndrome, phenylketonuria (PKU), Prader-Willi syndrome, Phelan-McDermid syndrome, Mowat-Wilson syndrome, genetic ciliopathy and SideriustypeX-linked intellectual disability are the caused by genetic or chromosomal abnormality and causes mental retardation.
  2. Problems during pregnancy – diseases that a mother contracts during pregnancy or consumption of alcohol or drugs during pregnancy can cause problems in the formation of the fetus resulting in mental retardation.
  3. Problems at birth – lack of oxygen, consumption of stool or any other problems during delivery can cause brain damage resulting in mental retardation.
  4. Exposure to certain types of diseases like whooping cough, measles, meningitis, etc or exposure to poisons like lead or mercury may also affect the brain and cause mental retardation.
  5. Iodine deficiency, goiter and cretinism can also cause mental retardation.
  6. Malnutrition is one of the common causes of mental retardation.
  7. Low birth weight – it is associated with poverty, problems during pregnancy, lack of proper development and nutrition during pregnancy all of which can be the cause of mental retardation directly, while low birth weight becomes an indirect indication towards more direct problems leading to mental retardation.
  8. Child abuse and neglect is also an indirect cause of mental retardation as it can lead to malnutrition or physical abuse both holding potential for damage to the bairn.

What are the symptoms of mental retardation?

Mental retardation can be detected in many cases can at a very early age, through these symptoms:

  1. Delays in mile stones like sitting up, crawling, talking, walking can be later than other children.
  2. Delays in oral language development.
  3. Deficits in memory skills.
  4. Difficulty learning social rules.
  5. Difficulty with problem solving skills.
  6. Delays in the development of adaptive behaviours such as self-help or self-care skills.
  7. Learn and grasp things slowly as compared to others

In some cases it may not be very prominent till the child faces difficulties in school or even later in life like college or work. Difficulties in social areas, decision making skills, inability to fulfil work commitments, lacking understanding in general can be found in adults with mental retardations.

What is the prevalence of mental retardation?

2.5 to 3 percent of the general population suffers from mental retardation. A survey done in India shows 27.5% of the child population in India suffers from mental retardation.


Mental retardation is found to be comorbid with the follow disorders –

  1. Epilepsy
  2. ADHD
  3. Pervasive development disorder
  4. Autism
  5. Personality and mood disorders
  6. Affective disorders
  7. Anxiety disorder
  8. Psychosis
  9. Sleep disorder
  10. Delirium

How to treat mental retardation?

  • Behavioural therapy for improvement of daily adjustments and functioning.
  • Remedial education for academic difficulty
  • Medication for any comorbid psychological difficulty.
  • Counselling for accompanying emotional problems like low self-confidence.
  • Familytherapies for helping the family adjust and deal with the individual with the disability.

Treatment depends upon the severity.

We at Mumbai Psychiatry Clinics have a dedicated team of counsellors and clinical psychologists who will help you with your problems, cite interventions and assess the progress on regular intervals. There are experienced psychiatrists who will be guiding you throughout your journey and our Multidisciplinary team will try to assure you with the best help possible.