According to the
on Mental Retardation (AAMR), an individual is considered to have
mental retardation based on the following three criteria:
functioning level (IQ) is below 70-75.
Significant limitations exist in two or more adaptive skill areas
and the condition is present from childhood (defined as age 18 or
The person's intellectual functioning is markedly below average (IQ
of 70 or less on a standard, individually administered test).
In 2 or more of the following areas, the patient has more trouble
functioning than would be expected for age and cultural group:
Social and interpersonal skills
Using community resources
Starts before age 18.
Under developed language skills
Under developed self-help skills
Developing at a far slower rate than the child's peers.
Some disorders have similar or even the same symptoms. The clinician,
therefore, in his/her diagnostic attempt, has to differentiate against
the following disorders which need to be ruled out to establish a
Mental retardation can be caused by any condition which impairs
development of the brain before birth, during birth, or in the childhood
years. Several hundred causes have been discovered, but in about one-third
of the people affected, the cause remains unknown. The three major
known causes of mental retardation are the genetic conditions of Down
X, and Fetal
Alcohol Syndrome, the result of alcohol consumption during pregnancy.