The causes can be generally categorised under:
- Genetic conditions
- Problems during pregnancy
- Prenatal problems
- Postnatal problems
- Poverty and cultural deprivation
The extent of retardation can be further divided into:
- Severely / profoundly impaired
- Trainable mentally retarded
- Educable mentally retarded
People with severe retardation have had very limited experiences and hence require a lot of inputs and stimulus.Characteristically, profoundly retarded people:
- Require one step directions. All instructions and steps should be broken down as understanding and following more than one thing at a time is very difficult.
- Require demonstration in concrete.
- Have poor motor and speech development.
- May have a problem using one or more parts of the body in a functional way.
- Require constant verbal cues through any activity.
- May “rock”, make noises and gestures that are incongruous.
- May exhibit “blindism” – rocking, flicking fingers in front of face, banging etc.
- May have distinguishing physical feature as in the case of people with Down syndrome.
- The IQ range is 10 to 34.
Trainable mentally retarded
The level of cognitive development and adaptive behaviour is severely below age expectations. The rate of learning as compared to the age would be one fourth to half.Characteristically, a trainable mental retarded is:
- Capable of being trained in socialisation and self help skills.
- Can communicate basic needs.
- Can carry on repetitive routine tasks.
- Can handle academics till class two level normally.
- Is usually passive slow moving and has gross and fine motor problems.
- Has difficulty relating self to space.
- Has a problem with abstractions.
- Has a short attention span and poor memory recall.
- Tends to be stubborn.
- May have other associated handicaps.
- The IQ range is 35 to 49.
Educable mentally retarded
At times children inflicted with this problem are also referred to as slow learners. These people learn at the rate of about half to three-fourths the rate of other people their age. At the elementary school level there is a two or three year maturation gap academically and a one or two year gap socially. At the junior school level this gap widens to three or four years and the gap continues to widen with age.A child with educable mental retardation:
- Is capable of being educated in all aspects of a regular curriculum.
- Can follow a series of instructions.
- Has various social skills.
- Has problems with abstract thought but can work around them in certain cases.
- Learns better in the concrete form.
- Has limited transfer skills.
- Needs repetitive directions.
- Has a relatively short attention span and impaired recall skills.
- Has no distinguishing physical characters.
- The IQ range is 50 to 69.