Mental retardation also known as intellectual disability or cognitive deficits occurs due to impaired intellectual function. It can be diagnosed in early childhood when the child shows limited ability to learn and memorize things. If the child’s intellectual ability is below 70 then he/she has cognitive deficits. Often such children cannot meet the daily demands of routine life and have impairment in education and learning skills. Mental retardation can cause serious effect on family relationship and can cause personality disorder.
Often children with MR will show aggressive behavior, impulsive reaction and stubbornness. They will cause self injury without knowing the consequences of their action. Most of them will have mood disorders, psychotic disorders and personality disorders. Some children with Down’s syndrome and autism will have distinctive structure (short) and other physical features marked for MR but others may have normal physical features with intellectual disability.
According to American Psychiatric Association, DSM – IV category divides the individuals according to the range of intellectual disability in varying degrees of severity. They are usually classified as mild, moderate, severe and profound mental retardation. Roughly 5% of the total population has intellectual disability and most of them are categorized in mild range. One should not classify children with learning disability or verbal disorder or attention deficit disorder under cognitive deficit since they have normal intelligence. Psychometric tests are to be administered for checking the intellectual quotient of a child.
The first symptom of mental retardation begins at the age of 3-5. There will be persistent infantile behavior, aggressiveness, learning disability, poor concentration, lack of curiosity and reduced socialization skills. It will start in the form of developmental delay for many children like delayed walking, delayed talking etc. Some parents will notice this delay only when the younger sibling meets up the development like regular children. If the impairment of cognitive deficit is less it will show in the form of difficulty in school when the child becomes incapable to read or remember math tables.
For many cases, there will not be any apparent cause for mental retardation. Reports state that only in 25% of the cases specific cause can be found and in most of the cases there is no clear evidence. The major cause for intellectual disability is yet to be found. Other common causes are chromosomal abnormalities, prenatal trauma like deprivation of oxygen to the brain, metabolic disorders, and congenital infection. Congenital infections like CMV, rubella, HIV and encephalitis and chromosomal abnormalities like deletions, translocations, defective chromosome and error in number of chromosomes can also cause mental retardation.
Deprivation from the home and lacking nutritional food can also contribute for this disorder. Genetic problems like galactosemia, Hunter syndrome, Lesch Nyhan syndrome, Tay Sachs disorder and metabolic disorders like Reye syndrome and hypoglycemia and toxic problems like lead poisoning and substance abuse during pregnancy can also cause this problem.
A series of assessment tests are available for testing the cognitive development. It includes IQ test, Stanford Binet intelligence scale, Bayley scale, and Wechsler intelligence scale. Most of them include questions that test the language development, mathematic reasoning, spatial ability and problem solving skills of the child. Based on the results the child will be categorized as mild, moderate or severely impaired with intelligence.
No treatment is available for mental retardation since it is inherited by birth and is not an acquired disease. Treatment/therapy is available for developing appropriate behaviors and for improving cognitive development of the child. Therapy is given to uncover the child’s potential in full. Special education is given for such children. Nutritional deficiency can be corrected by taking healthy diet plan by the child. Medications are given for treating psychiatric problems, personality disorder and behavior problems.
Specific disability like cardiac problem, endocrine or orthopedic disorders can be repaired through surgery. Behavior therapy with medications is recommended for children with attention deficit disorder, and autism. The treatment should be oriented in developing their overall social skills.
Medications prescribed for correcting attention deficit include methylphenidate or detroamphetamine. For managing aggressive nature and irritability clonidine and antipsychotics like risperidone are given. For controlling anxiety related problems drugs like wellbutrin and fluoxetine are prescribed. Therapies like physiotherapy, speech therapy, recreation therapy and behavioral counseling is provided to the affected child. Special education is needed for such children and they also need help from various training groups for acquiring skills.