Mental retardation is a disability that is characterized by significant limitations that are both intellectual functioning and in adaptive behavior that are expressed in conceptual, social and practical skills. This will mean that such a problem will be from the age of about 18 years of age. This problem can occur to people from all races; ethnic, educational and social background meaning this problem is not made to a certain ethnic group but can occur to all in a country.
Read more on Mental Retardation Disability here...