Mental retardation is a term that was once commonly used to describe someone who learns and develops more slowly than other kids. But it’s not used as much anymore because it hurts people’s feelings.

Mental retardation affects about 1 – 3% of the population. There are many causes of mental retardation, but doctors find a specific reason in only 25% of cases.The degree of impairment from mental retardation varies widely, from profoundly impaired to mild or borderline retardation. Less emphasis is now placed on the degree of retardation and more on the amount of intervention and care needed for daily life. One can recognize different types of developmental disabilities, depending on what function or functions are affected and how extensive is the limitation.