Mental Retardation

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Mental Retardation Definition Symptoms Cause Diet Regimen Homeopathic Medicine Homeopath Treatment In Rajkot India

The Mental Retardation:

Mental Retardation (MR)


Mental retardation is a term for a pattern of persistently slow learning of basic motor and language skills (milestones) during childhood, and a significantly below-normal global intellectual capacity as an adult. [2]

Mental retardation is defined as significantly sub average general intellectual functioning, associated with significant deficit or impairment in adaptive functioning, which manifests during the developmental period (before 18 years of age). [1]

Generally, One common criteria for diagnosis of mental retardation is a tested intelligence quotient (IQ) of 70 or below and deficits in adaptive functioning.

Moreover, People with mental retardation may be described as having developmental disabilities, global developmental delay, or learning difficulties. [2]

All in all, General intellectual functioning is usually assessed on a standardised intelligence test with significantly sub average intelligence as two standard deviations below the mean (usually an IQ of below 70), whilst adaptive behaviour is the person’s ability to meet responsibilities of social, personal, occupational and interpersonal areas of life, appropriate to age, sociocultural also educational background. [1]

Adaptive behaviors:

These are skills necessary for day-to-day life, such as being able to communicate effectively, interact with others, and take care of oneself.

Adaptive behaviour is measured by clinical interview and standardised assessment scales.

A classification of mental retardation on the basis of IQ ( Intelligence Quotient, which is equal to mental age, i.e. MA, divided by chronological age, i.e. CA, multiplied by 100; i.e. IQ = MA/CA × 100).

1. Mild Mental Retardation:

  • This is the commonest type of mental retardation, accounting for 85-90% of all cases.
  • The diagnosis is made usually later than in other types of mental retardation.
  • In the preschool period (before 5 years of age), these children often develop like other normal children, with very little deficit.
  • Later, they often progress up to the 6th class (grade) in school and can achieve vocational and social self sufficiency with a little support.
  • Only under stressful conditions or in the presence of an associated disease, supervised care may be needed.
  • This group has been referred to as ‘educable’ in a previous educational classification of mental retardation. [1]

Some of the following symptoms of mild MR include:

  • taking longer to learn to talk, but communicating well once they know how
  • being fully independent in self-care when they get older
  • having problems with reading and writing
  • social immaturity
  • inability to deal with the responsibilities of marriage or parenting
  • benefiting from specialized education plans
  • having an IQ range of 50 to 69 [3]

2. Moderate Mental Retardation:

  • About 10% of all persons with mental retardation have an IQ between 35 and 50.
  • In the educational classification, this group was earlier called as ‘trainable’, although many of these persons can also be educated.
  • In the early years, despite a poor social awareness, these children can learn to speak.
  • Often, they drop out of school after the 2nd class (grade).
  • They can be trained to support themselves by performing semiskilled or unskilled work under supervision.
  • A mild stress may destabilise them from their adaptation; thus they work best in supervised occupational settings. [1]

If your child has moderate MR, they may exhibit some of the following symptoms:

  • are slow in understanding also using language
  • may have some difficulties with communication
  • can learn basic reading, writing, and counting skills
  • are generally unable to live alone
  • can often get around on their own to familiar places
  • can take part in various types of social activities
  • generally have an IQ range of 35 to 49 [3]

3. Severe Mental Retardation:

  • Severe mental retardation is often recognised early in life with poor motor development (significantly delayed developmental milestones) also absent or markedly delayed speech and other communication skills.
  • Later in life, elementary training in personal health care can be given and they can be taught to talk.
  • At best, they can perform simple tasks under close supervision. In the earlier educational classification, they were called as ‘dependent’. [1]

Symptoms include:

  • noticeable motor impairment
  • severe damage to, or abnormal development of, their central nervous system
  • generally have an IQ range of 20 to 34 [3]

4. Profound Mental Retardation:

  • This group accounts for about 1-2% of all persons with mental retardation.
  • The associated physical disorders, which often contribute to mental retardation, are common in this subtype.
  • The achievement of developmental milestones is markedly delayed.
  • They often need nursing care or ‘life support’ under a carefully planned and structured environment (such as group homes or residential placements). [1]

Symptoms of profound MR include:

  • inability to understand or comply with requests or instructions
  • possible immobility
  • incontinence
  • very basic nonverbal communication
  • inability to care for their own needs independently
  • the need of constant help and supervision
  • having an IQ of less than 20 [3]

There are many signs:

  1. Children with developmental disabilities may learn to sit up, to crawl, or to walk later than other children, or they may learn to talk later.
  2. Both adults and children with intellectual disabilities may also have trouble in speaking, find it hard to remember things, have trouble understanding social rules.
  3. Have trouble discerning cause and effect.
  4. Trouble solving problems.
  5. Have trouble thinking logically.
  6. In early childhood mild disability (IQ 60-70) may not be obvious, and may not be diagnosed until they begin school.
  7. Even when poor academic performance is recognized, it may take expert assessment to distinguish mild mental disability from learning disability or behaviour problems.
  8. As they become adults, many people can live independently and may be considered by others in their community as “slow” rather than foolish.
  9. Moderate disability (IQ 50-60) is nearly always obvious within the first years of life.
  10. These people will encounter difficulty in school, at home, and in the community.
  11. In many cases they will need to join special, usually separate, classes in school, but they can still progress to become functioning members of society.

Other symptoms:

  1. As adults they may live with their parents, in a supportive group home, or even semi-independently with significant supportive services to help them, for example, manage their finances.
  2. Among people with intellectual disabilities, only about one in eight will score below 50 on IQ tests.
  3. A person with a more severe disability will need more intensive support and supervision in his or her entire life.
  4. The limitations of cognitive function will cause a child to learn and develop more slowly than a typical child.
  5. Children may take longer to learn to speak, walk, and take care of their personal needs such as dressing or eating.
  6. Learning will take them longer, require more repetition, and there may be some things they cannot learn.
  7. The extent of the limits of learning is a function of the severity of the disability.
  8. Nevertheless, virtually every child is able to learn, develop, and grow to some extent. [2]

1. Genetic (probably in 5% of cases):

i. Chromosomal abnormalities (such as Down’s syndrome, Fragile-X syndrome, Turner’s syndrome, Klinefelter’s syndrome)

ii. Inborn errors of metabolism, involving amino acids, lipids, carbohydrates, purines, and mucopolysaccharides.

iii. Single-gene disorders (such as tuberous sclerosis, neurofibromatosis, dystrophia myotonica)

iv. Cranial anomalies (such as microcephaly)

2. Perinatal causes (probably in 10% of cases):

i. Infections (such as rubella, syphilis, toxoplasmosis, cytomegalo-inclusion body disease)

ii. Prematurity

iii. Birth trauma

iv. Hypoxia

v. Intrauterine growth retardation (IUGR)

vi. Kernicterus

vii. Placental abnormalities

viii. Drugs during first trimester.

3. Acquired physical disorders in childhood (probably in 2-5% of cases):

i. Infections, especially encephalopathies

ii. Cretinism

iii. Trauma

iv. Lead poisoning

v. Cerebral palsy.

4. Sociocultural causes (probably in 15% of cases):

i. Deprivation of sociocultural stimulation.

5. Psychiatric disorders (probably in 1-2% of cases):

i. Pervasive developmental disorders (such as Infantile autism)

ii. Childhood onset schizophrenia. [1]

4. Health problems:

Diseases like whooping cough, measles, or meningitis can cause mental disability. It can also be caused by not getting enough medical care, or by being exposed to poisons like lead or mercury.

5. Iodine deficiency:

It affecting approximately 2 billion people worldwide, is the leading preventable cause of mental disability in areas of the developing world where iodine deficiency is endemic.

Iodine deficiency also causes goiter, an enlargement of the thyroid gland. [2]

According to the latest edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM IV), there are three criteria before a person is considered to have a developmental disability.

An IQ below 70, significant limitations in two or more areas of adaptive behaviour (i.e, ability to function at age level in an ordinary environment), and evidence that the limitations became apparent in childhood.

It is formally diagnosed by professional assessment of intelligence and adaptive behaviour.

The following ranges, based on the Wechsler Adult Intelligence Scale (WAIS), are in standard use today:

  1. Class IQ.
  2. Profound mental retardation below 20.
  3. Severe mental retardation 20-34.
  4. Moderate mental retardation 35-49.
  5. Mild mental retardation 50-69.
  6. Borderline mental retardation 70-79. [2]

The diagnosis is made by the following steps:


General physical examination

Detailed neurological examination

Mental status examination, for the assessment of associated psychiatric disorders and the clinical assessment of the level of intelligence.


i. Routine investigations.

ii. Urine test, e.g. for phenylketonuria, maple syrup urine disease.

iii. EEG, especially in presence of seizures. iv. Blood levels, for inborn errors of metabolism.

v. Chromosomal studies, e.g. in Down’s syndrome, prenatal (by amniocentesis or chorionic villus biopsy) and postnatal.

vi. CT scan or MRI scan of brain, e.g. in tuberous scle ro sis, focal seizures, unexplained neurological syndromes, anomalies of skull confi guration, severe or profound mental retardation without any apparent cause, toxoplasmosis.

vii. Thyroid function tests, particularly when cretinism is suspected.

viii. Liver function tests, e.g. in mucopolysaccharidosis.

Psychological tests:

The commonly used tests for measurement of intelligence i.e.:

i. Seguin form board test.

ii. Stanford-Binet, Binet-Simon or Binet-Kamath tests.

iii. Wechsler Intelligence Scale for Children (WISC) for 6½ to 16 years of age.

iv. Wechsler’s Preschool also Primary Scale of Intelligence (WPPSI) for 4 to 6½ years of age.

v. Bhatia’s battery of performance tests.

vi. Raven’s progressive matrices (e.g. coloured, standard and advanced).

The tests used for the assessment of adaptive behaviour include:

i. Vineland Social Maturity Scale (in other words; VSMS).

ii. Denver Development Screening Test (in other words; DDST).

iii. Gesell’s Development Scale. [1]

Primary Prevention:

This consists of i.e.:

  • In general, Improvement in socioeconomic condition of society at large, aiming at elimination of under-stimulation, malnutrition, prematurity also perinatal factors.
  • Moreover, Education of lay public, aiming at removal of the misconceptions about individuals with mental retardation.
  • Medical measures for good perinatal medical care to prevent infections, trauma, excessive use of medications, malnutrition, obstetric complications, and diseases of pregnancy.
  • Besides this, Universal immunisation of children with BCG, polio, DPT, and MMR.
  • Facilitating research activities to study the causes of mental retardation also their treatment.
  • All in all, Genetic counselling in at risk parents, e.g. in phenylketonuria, Down’s syndrome.

Secondary Prevention:

  • Basically, Early detection and treatment of preventable disorders, e.g. phenylketonuria (low phenylalanine diet), maple syrup urine disease (low branched amino-acid diet) and hypothyroidism (thyroxine).
  • Detection of handicaps in sensory, either motor or behavioural areas with early remedial measures and treatment.
  • Early treatment of correctable disorders, e.g. infections (antibiotics), skull configuration anomalies (surgical correction).
  • Besides this, Early recognition of presence of mental retardation. A delay in diagnosis may cause unfortunate delay in rehabilitation.
  • As far as possible, individuals with mental retardation should be integrated with normal individuals in society, also any kind of segregation or discrimination should be actively avoided.
  • Lastly, They should be provided with facilities to enable them to reach their own full potential. However, there is a role of special schools for those with more severe mental retardation.

Tertiary Prevention:

Adequate treatment of psychological also behavioural problems.

Behaviour modification, using the principles of positive also negative reinforcement.

Rehabilitation in vocational, physical, also social areas, commensurate with the level of disability.

Parental counselling is extremely important to lessen the levels of stress, teaching them to adapt to the situation, enlisting them (especially parents) as co-therapists, and encouraging formation of parents’ or carers’ organisation and self-help groups.

Either Institutionalisation or residential care may be needed for individuals with profound mental retardation.

Legislation: In 1995, the ‘Persons with Disability Act’ came into being in India. This act envisages mandatory support for prevention, early detection, education, employment, and other facilities for the welfare of persons with disabilities in general, and mental retardation in particular.

This Act provides for affirmative action also non-discrimination of persons with disabilities.

In 1999, the ‘National Trust Act’ came in to force. All in all, This Act proposes to involve the parents of mentally challenged persons and voluntary organisations in setting up and running a variety of services and facilities with governmental funding.


Marked emaciation of legs, old looking skin, flabby and hangs loose in folds, cannot hold up the head.

In detail, Sensitive tendency, cross, irritable, depressed peevish, cruel troubling others kills small insects, beats pets. No manners. Additionally, It’s difficult for him to enjoy with others.

Baryta Carbonica:

Dwarfish appearance. Additionally, Mentally deficient and physically weak and short.

Typical picture of cretinism having short stature swollen abdomen, puffy face, enlarged glands, thick lips also idiotic appearance.

Idiotic foolish, with loss of memory, shy, nervous in front of strangers, hides behind the furniture, bashful, timid, easily frightened children do not want to play.

Sits in the corner and throws stones at strangers. Besides this, Inattentive, milestones are delayed, late learning to walk. This could be either due to defects of development or due to premature degeneration.

Calcarea Carbonica:

Children who grow fat chalky look with red face, large belly like inverted saucer with large head also open fontanelles and sutures.

Pale skin, soft bones, who sweat easily especially on the backside and neck, slowness, delayed skills-walking, talking, etc., slow comprehension in school, poor recall, mistakes in reading also writing.

Forgetfulness, forgets what he has read soon after. Fear of dark, spiders’ insects’ animals and ghosts, startles easily. Cannot calculate. Additionally, Cannot do deep thinking. Wants to be magnetized.

Fungi group (Remedies):

It has been seen that the group of fungus remedies is useful in cases of mental retardation. Following are the common symptoms found i.e.:

  •  Absent minded.
  • Confused behaviour.
  • Dullness, difficulty in thinking.
  • Indifference, apathy to everything.
  • Memory weakness.
  • Awkwardness.
  • Concentration difficult.
  • Forgetful.
  • Indolence, aversion to work.
  • Imbecility.


  • Dullness and sluggishness in children.
  • Forgets his own name.
  • Hurry, imbecility, impatient, irritability, difficult concentration.
  • Weakness of memory.
  • Makes mistakes in spelling.
  • Excitement while writing.
  • Confused mind.
  • Delusions, hallucinations, illusions of animals.
  • It has organic brain syndrome which includes delirium, dementia, head excitement, etc.
  • Religious affections, selfishness.
  • Slow learners. [2]

Frequently Asked Questions

What is Mental Retardation?

Mental retardation is a term for a pattern of persistently slow learning of basic motor and language skills (milestones) during childhood, and a significantly below-normal global intellectual capacity as an adult.

Homeopathic Medicines used by Homeopathic Doctors in treatment of Mental Retardation?

  • Abrotanum
  • Baryta Carb
  • Calcarea Carb
  • Medorrhinum

What causes Mental Retardation?

  • Chromosomal abnormalities
  • Inborn errors of metabolism
  • Single-gene disorders
  • Cranial anomalies
  • Perinatal causes (Infections, Prematurity, Birth trauma)
  • Acquired physical disorders in childhood
  • Sociocultural cause
  • Psychiatric disorders
  • Iodine deficiency

Give the types of Mental Retardation?

What are the symptoms of Mental Retardation?

  • Children with developmental disabilities
  • Intellectual disabilities
  • Have trouble discerning cause and effect.
  • Trouble solving problems.
  • Have trouble thinking logically
  • Poor academic performance

A Short Textbook of Psychiatry by Niraj Ahuja / Ch 13.

Homeopathy in treatment of Psychological Disorders by Shilpa Harwani / Ch 20.

Excerpts (Summary)

Table of Contents

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