Health
Fact-checked

At TheHealthBoard, we're committed to delivering accurate, trustworthy information. Our expert-authored content is rigorously fact-checked and sourced from credible authorities. Discover how we uphold the highest standards in providing you with reliable knowledge.

Learn more...

What Is Intellectual Impairment?

Wanda Marie Thibodeaux
Wanda Marie Thibodeaux

Intellectual impairment, also known as mental or cognitive impairment, is cognitive functioning that is below normal and which impacts everyday life. The internationally accepted definition according to the American Association on Intellectual & Developmental Disabilities (AAIDD) is that intellectual impairment is demonstrated when a person's intellectual function and the ability to adapt is shown to have dramatic limitations, as demonstrated by their social and practical skills. The impairment must also originate before the age of 18. Cognitive impairment typically means that a person needs adjustments in educational approaches, and in some cases, assistance in living. It does not necessarily mean a person cannot be a positive contributor to society.

When a person has mental impairment, their capacity for performing mental tasks and problem solving is lower than average. At the very least, this usually means the individual needs some additional time to complete what he is doing. In the worst case, it means the individual becomes completely dependent on other individuals and needs supervision throughout the entire day. Thus, a broad range of intellectual impairment exists.

A child who is malnourished may exhibit a higher level of intellectual impairment when compared to her peers.
A child who is malnourished may exhibit a higher level of intellectual impairment when compared to her peers.

Intellectual impairment is divided into four basic categories that describe the level of impairment. These include mild, moderate, severe and profound. A classification of mild means the individual has an intellectual quotient (IQ) between 51 and 70. Moderate mental impairment means an IQ of 36 to 50. Experts give a designation of severe impairment when an IQ is 21 to 35. With an IQ of 20 or less, an individual is severely impaired.

Memory problems and short attention spans are common signs of an intellectual disability.
Memory problems and short attention spans are common signs of an intellectual disability.

People who are intellectually impaired exhibit symptoms such as disorganization in learning and understanding abstract constructs. The ability to learn is necessary to adapt and change, so another symptom is problems with adaptive skills. Examples of adaptive skill areas include social interaction, work and health and safety.

Intellectual impairment is not always considered a disability, but it can be. In this instance, it might be covered by anti-discrimination laws present in the country in which the person lives. For example, in the United States, intellectual impairment is covered by the Americans With Disabilities Act (ADA). This law considers intellectual impairment a disability if a) the impairment limits one or more major life activities such as caring for oneself or working, b) the intellectual impairment combined with another impairment limits one or more major life activities, c) the individual has a history of substantial intellectual impairment or d) no mental impairment is present but others treat the individual as if it is.

Intellectual impairment is considered a disability if an individual has a history of substantial intellectual impairment.
Intellectual impairment is considered a disability if an individual has a history of substantial intellectual impairment.

Doctors and scientists believe some cases of intellectual impairment are purely genetic in origin. Other cases are related to controllable factors such as maternal drug use — including some prescription medications — that causes problems in fetal brain development. Cases of brain injury also can cause issues with mental functioning, but because brain injury and subsequent cognitive problems don't always result prior to age 18, not all of these cases technically can be classed as an intellectual impairment according to the definition set by AAIDD.

Discuss this Article

Post your comments
Login:
Forgot password?
Register:
    • A child who is malnourished may exhibit a higher level of intellectual impairment when compared to her peers.
      By: Tatyana Gladskih
      A child who is malnourished may exhibit a higher level of intellectual impairment when compared to her peers.
    • Memory problems and short attention spans are common signs of an intellectual disability.
      By: kmiragaya
      Memory problems and short attention spans are common signs of an intellectual disability.
    • Intellectual impairment is considered a disability if an individual has a history of substantial intellectual impairment.
      By: Miriam Dörr
      Intellectual impairment is considered a disability if an individual has a history of substantial intellectual impairment.
    • It's estimated that about 6.5 million Americans have some type of intellectual disability.
      By: Monkey Business
      It's estimated that about 6.5 million Americans have some type of intellectual disability.
    • Intellectual impairment may occur as a result of a head injury.
      By: william87
      Intellectual impairment may occur as a result of a head injury.
    • Medication may be used to treat some cases of impaired cognition.
      By: Andy Dean
      Medication may be used to treat some cases of impaired cognition.