MENTAL RETARDATION

MENTAL RETARDATION

Mental retardation is the state of arrested or incomplete development of intellectual functions characterized by impairment in cognitive, language, motor and social skills, manifested at birth or early childhood.

In a normal child the Chronological Age (CA) equals the Mental Age (MA).

Intelligent Quotient (IQ) = Mental Age (MA) divided by Chronological age (CA), the whole multiplied by 100.

IQ provides a rough measure of a child’s level of intellectual functioning and is used to screen those suspected to have mental retardation. But IQ does not reveal the capacity for adaptive behaviour of the child which is also a measure of intelligence. Milestones are delayed in Mental retardation.

Developmental Milestones

Age	Motor Activity	Social Activity	Mental Activity
1-2 months	Sleeps most of the time but while awake waves both his arms and legs Grasps things when put in hand. Holds head for a few seconds.	---	Cries differently
2-3 months	Eyes follow bright light. Fixes eyes on mother	Smiles at mother	---
4-5 months	Holds head steadily. Tries to roll over. Plays with fingers. Eyes follow moving objects. Sleeps for 20 hours a day.	Makes cooing sounds. Recognizes mother	Recognizes mother.
6 months	Sits without support. Plays with toes. Reaches and grasps things. Sleeps for 18 hours a day	Recognizes friends. Smiles and laughs	Shows pleasure by smiling and displeasure by crying.
9 months	Sits up alone. Crawls towards objects. Tries to pull himself      up. Sleeps 16-17 hours a day.	---	Says one or two syllables
12 months	Stands alone. Walk with support. Feeds himself with fingers. Sleeps for 16 hours a day	Understands the meaning of yes  and no.	Says 2-3 words. Gazes at simple pictures and mirror.
18 months	Throws a ball. Walks easily. Plays with toys. Drinks from glass or cup.	Prefers to play Alone	Says a few words
2 yrs	Runs. Climbs on stools. Balances on one foot. Sleeps for 14 hours a day.	Helps to wash and dress himself	Talks well. Says short sentences, names, familiar things. Copies a circle.
3 yrs	Runs quickly, jumps, rides a bicycle, attains bladder control, Buttons and unbuttons clothes.	Plays simple  games with other   children	Points to all familiar things
4-5 yrs	Hope on one foot. Sleeps 12 hours a day. Dresses and undresses without support	Plays with other children	Counts objects and up to 10 or more, Makes simple drawings with crayons, knows names of colours, knows right or left and morning and evening

CLASSIFICATION

1. Mild mental retardation                   IQ 50-69
2. Moderate Mental retardation          IQ 35-49
3. Severe Mental Retardation              IQ 20-34
4. Profound Mental Retardation         IQ less than 20

Mild Mental Retardation (IQ 50-69)

In preschool years they are usually indistinguishable from children with normal intelligence and problems of learning are only defected once they enter school. Sensory and motor impairment is minimal and non conspicuous. They can develop social and communication skills adequate for a self supportive life in adulthood. They are able to achieve academic skills of about 6^th grade by late teens. As adults they have a mental age of 9-12 yrs. They can lead to a successful and independent life ordinarily, but may need help under stressful social and economic situations. Marriage and child rearing may pose problems. They used to be referred to as the educable group of the mentally retarded. Unskilled or semi skilled manual work is accomplished with no difficulty.

Moderate Mental Retardation (IQ 35-49)

As adults they reach a mental age of 6-8 years and 2^nd grade level of academic skills. Most can talk and engage in simple instructions. Social and interpersonal skills are poor. They need training in self help and social and occupational skill from which they can profit. Simple routine work could be undertaken by them in familiar surroundings. They need supervision and guidance and leading an independent life is not possible. They may undertake skilled and semiskilled work under sheltered conditions. They usually referred as the ‘trainable group’.

Severe Mental Retardation (IQ 20-34)

As adults their mental age corresponds to 3-6 years. There is a marked motor impairment and in the preschool years their development milestones are delayed. Associated handicaps are often seen and need to be attended too. Speech is minimal and communication skills are very poor. With training they are able to develop self protective skills and simple skills can be performed under supervision.

Profound Mental Retardation (IQ below 20)

They attain the mental age of less than 3 years as adults. Their communication skills are limited to very simple commands and requests. They need a highly structured protective environment and require continuous supervision and nursing care.

Causes of Mental Retardation

                                                                                   Psycho-social Causes

            

                                                                                                * Poverty and Malnutrition

                                                                                                                    * Familial retardation

Biological Causes 

Prenatal Factors       Prenatal Factors        Postnatal Factors                           

* Genetic and                                * Birth injury                             * Infections

   chromosomal                                                                                                        

   aberration                                     * Kernicterus                              * Cerebral Palsy                   

* Prematurely                                                                       

* Congenital anomalies                                                                               * Trauma

                                                                                                                              

* Meternal infections,                                                                                        * Intoxications

   intoxications and

   teratogens during

   pregnancy                                                                                            

                           

 * Complications of

    Pregnancy