Mental Retardation is a non-curable intellectual impairment which affects the learning ability of an individual. People with mental retardation are slow learners and may also be impaired in their social adaptation. Impairment is permanent, but can be compensated through development of the person's full potential. In many cases, there is no known cause for mental retardation, though women who drink alcohol during pregnancy increase their risks of having a child born with impairments which may include mental retardation . It is however, one of the most preventable of disabilities.
Mental illnesses are brain diseases, biologically based.
The two are not the same. Early intervention, peer acceptance, special education, having friends, and independent living.