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Education of Individuals With Mental Retardation - Definition and Prevalence of Mental Retardation, Brief History of Education

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Throughout history, the definition, diagnosis, terminology, and etiology of mental retardation have changed, influencing services, policy, education, and prevalence.

Definition and Prevalence of Mental Retardation

Mental retardation is a condition of substantial limitations in intellectual functioning that impacts performance in daily life. Its diagnosis includes three criteria: concurrent, significant limitations in both intelligence and adaptive skills that begin in childhood (birth to age eighteen). The American Association on Mental Retardation's (AAMR's) 1992 definition specifies limitations of two or more standard deviations in intelligence (IQ of 70 to 75 or less) with coexisting deficiencies in two or more of ten adaptive skills: communication, self-care, home living, social skills, community use, self-direction, health and safety, functional academics, leisure, and work. These individuals range broadly in functioning, depending in part on the degree of limitations but also on the services and support received. Individuals with severe and multiple disabilities are considered a small subset of this population. Most persons with mental retardation are capable of achieving self-sufficiency. A 1998 study indicates that prevalence estimates cluster around 1 percent, with a high of 2 percent.

Brief History of Education

Prior to the 1700s, those with mental retardation suffered greatly. In the 1700s to the late 1800s, they entered an optimistic period when French educational methods spread to other Western countries. These methods derived mainly from Edward Seguin and less so from his predecessor Jean-Marc Itard in the first half of the nineteenth century. Seguin called his educational methods physiological education, which consisted of three components: muscular or physical education, education of the senses, and moral treatment. The goal of Seguin's method was independence grounded in relationships with other citizens, not isolation from society. These educational methods produced uneven results and were followed by disillusionment.

In the late 1800s to the 1960s there was widespread building of institutions to house individuals with mental retardation. Intelligence tests, developed in the early 1900s, became the tools of the eugenic movement–a period when many people with low intelligence were sterilized under the assumption that the population would be improved. Starting in the 1970s the institutional population in the United States was gradually reduced, primarily because of a reduction in admissions. Many former residents were relocated to smaller community-based settings, but others remained in their natural homes with services and supports provided. Of those remaining in state institutions at the end of the twentieth century, persons over forty with profound mental retardation and multiple disabilities dominated the population.

Schools' Responses and Goals and Methods of Teaching

Before 1975 when the Education of All Handicapped Children Act was passed (Pub. L. 94-142) and special education was required, some students with milder mental retardation attended school until they failed or quit, but others with greater support needs attended parent-operated schools or remained at home. The number of individuals with mental retardation in institutions reached its peak in the mid-1960s, where educational services of widely varying quality sometimes existed. According to the U.S. Department of Education's statistics, at the end of the twentieth century students with labels of mental retardation who were enrolled in U.S. public schools constituted 11 percent of all students with disabilities. The number of students classified as having mental retardation declined substantially since the 1970s, in part because of the label's stigma and recognition of intelligence test inaccuracy. Minority children were overrepresented in school programs serving those with mental retardation, a fact often accounted for by inaccurate testing.

The primary goal of education for this group is to increase self-sufficiency by teaching functional academics and other skills needed in everyday life across home, community, work, and leisure domains. Depending on the student's abilities (conceptual, social, and practical), needs for support (intermittent to pervasive), and school placement, the educational focus and methods will vary. The socioeconomic level of the community influences the quality of special education and the amount of support an individual receives in school and during adult life.

Issues Trends and Controversies

Although the label of mental retardation brings services, it also brings stigma and low expectations. The reduction in students labeled as mentally retarded (with a corresponding increase in those with learning disabilities) from the 1970s to the 1990s serves as evidence. Parents and educators have grappled with this issue. Some believe the label should be reserved for those with organic etiologies, assuming the smaller group would be more homogeneous. Others propose a change in the label and improved education of the public.

Current law requires education in the least restrictive environment with appropriate services and support. Students with mental retardation have a poor record for being served in general education classrooms: 46 percent of all students with disabilities are so served compared with 12 percent of those with mental retardation. Many believe that educators need to understand better how to serve these students in the mainstream and also equip them for the transition to adult life.


ANDERSON, LYNDA L., et al. 1998. "State Institutions: Thirty Years of Depopulation and Closure." Mental Retardation 36:431–443.

BEIRNE-SMITH, MARY; ITTENBACK, RICHARD F.; and PATTON, JAMES R. 1998. Mental Retardation, 5th edition. Upper Saddle River, NJ: Merrill/Prentice-Hall.

Education of All Handicapped Children Act of 1975. U.S. Public Law 94-142. U.S. Code. Vol. 20, secs. 1401 et seq.

GRESHAM, FRANK M.; MACMILLAN, DONALD L.; and SIPERSTEIN, GARY N. 1995. "Critical Analysis of the 1992 AAMR Definition: Implications for School Psychology." School Psychology Quarterly 10:1–19.

Individuals with Disabilities Education Act Amendments of 1997. U.S. Public Law 105-12. U.S. Code. Vol. 20, secs. 1400 et seq.

LUCKASSON, RUTH, et al. 1992. Mental Retardation: Definition, Classification and Systems of Supports, 9th edition. Washington, DC: American Association on Mental Retardation.

TRENT, JAMESW., JR. 1994. Inventing the Feeble Mind: A History of Mental Retardation in the United States. Berkeley: University of California Press.

U.S. DEPARTMENT OF EDUCATION. 2000. Twenty-Second Annual Report to Congress on the Implementation of the Individuals with Disabilities Education Act. Washington, DC: Office of Special Education Programs, U.S. Department of Education.


Mentoring - Rationale for Mentoring, Extensiveness of Mentoring Programs, Issues and Controversies [next] [back] Mental Health Services and Children - Who Receives Mental Health Services?, Use of Services, Where Do Children Receive Mental Health Services?

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about 6 years ago

Dear Sir / Madam
My 10 yrs old son is Mental Retardation due to ADD / ADHD and (Slow learner) in Special School ,

and there is no any particular school here,

any way, have you any solution, therapy,/ medication


Special Education to make him a normal person, Believe me I am very worried about him, and ready to go any aboard for his best future,

Best & Regards
Arshad Ali