Definitions of Intellectual Disabilities/Mental Retardation - Worksheet

1. Mental retardation refers to significantly subaverage general intellectual functioning which originates during the developmental period and is associated with impairment in adaptive behavior.

Subaverage Intellectual Functioning: one or more standard deviations (SD's) below the mean. (An IQ score of 85 or below)

Adaptive Behavior: adaptation to the demands of the environment.


2. Mental retardation refers to significantly subaverage general intellectual functioning existing concurrently with deficits in adaptive behavior and manifested during the developmental period.

Subaverage Intellectual Functioning: at least two standard deviations below the mean (current functioning - not permanent status). (An IQ of 70 score or below)

Adaptive Behavior: ability to meet the standards of personal independence and social responsibility expected of his/her age level and cultural group.

Dev. Period: birth to age 18.



3. Mental retardation refers to significantly subaverage general intellectual functioning existing concurrently with deficits in adaptive behavior and manifested during the developmental period.

Subaverage Intellectual Functioning: two or more standard deviations below average--but a small number of persons with scores up to 10 points above the guideline ceiling may be classified as mildly mentally retarded if their adaptive behavior is significantly impaired (current functioning - not permanent status) (An IQ score of 70 - 80 or below).

Adaptive Behavior: same as 2.

Dev. Period: same as 2.



4. Mental retardation refers to substantial limitations in present functioning. It is characterized by significantly subaverage general intellectual functioning existing concurrently with related limitations in two or more of the following applicable adaptive skills areas: communication, self-care, home living, social skills, self-direction, health and safety, functional academics, leisure, and work. Mental retardation manifests before age 18.

Significantly Subaverage Intellectual Functioning: same as 3 (An IQ score of 70 - 75 or below)


5. Mental Retardation is a disability characterized by significant limitations both in intellectual functioning and in adaptive behavior as expressed in conceptual, social, and practical adaptive skills. This disability originates before the age of 18.

Significant Limitations in Intellectual Functioning: same as 3 (An IQ score of 70 - 75 or below)

Adaptive Behavior: “The collection of conceptual, social, and practical skills people have learned so they can function in their lives. Significant limitations . . .  impact a person’s daily life and affect the ability to respond to . . . the environment.” In order to meet this criterion, the person must perform at a level two or more standard deviations below the mean (average) in one of the three areas (conceptual, social, or practical) or have an overall score that is two or more standard deviations below average on a standardized measure of adaptive behavior.


6.  Intellectual Disability is a disability characterized by significant limitations both in intellectual functioning and in adaptive behavior as expressed in conceptual, social, and practical adaptive skills. This disability originates before the age of 18. 

Significant Limitations in Intellectual Functioning: same as 3 (An IQ score of 70 - 75 or below)

Adaptive Behavior: Same as 5.
 


7. Mental Deficiency: A state of incomplete mental development of such a kind and degree that the individual is incapable of adapting himself to the normal environment of his fellows in such a way to maintain existence independently of supervision, control or external support.


8. Six criteria are necessary for the diagnosis of mental deficiency : 1) social incompetence; 2) mental subnormality; 3) which has been developmentally arrested; 4) which obtains at maturity 5) is of constitutional origin; and 6) is essentially incurable.


9. An idiot is one who hath no understanding from his nativity.


10. An idiot is such a person who cannot account or number, nor can tell who was his father or mother, nor how old he is, so as it may appear he has not understanding or reason of what shall be his profit or his loss.


11. Idiocy (involves) deficiency in the ordinary mental powers, due to disease or failure of development of the central nervous system. More especially, idiocy often relates to the severer forms of such mental deficiency , while children of subnormal capacity or backward development are spoken of as feeble-minded, or mentally deficient children. There is some tendency to use the term feeble-minded to include all degrees of defect from the slightest to the most severe.


12. Idiocy is a specific infirmity of the cranio-spinal axis, produced by deficiency of nutrition in utero and neo-nati. It incapacitates mostly the functions which give rise to the reflex, instinctive, and conscious phenomena of life; consequently, the idiot moves, feels, understands, wills, but imperfectly; does nothing, thinks of nothing, cares for nothing (extreme cases), he is legally irresponsible; isolated, without associations; a soul shut up in imperfect organs, an innocent.


13. Intellectual Disability is a disability characterized by significant limitations both in intellectual functioning and in adaptive behavior as expressed in conceptual, social, and practical adaptive skills. This disability originates before the age of 18. 
 

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