What are intellectual and developmental disabilities?
Intellectual disability is a disability characterized by significant limitations in both intellectual functioning and in adaptive behavior, which covers many everyday social and practical skills. This disability originates before the age of 22.
Intellectual Functioning: Intellectual functioning—also called intelligence—refers to general mental capacity, such as learning, reasoning, problem solving, and so on.
One way to measure intellectual functioning is an IQ test. Generally, an IQ test score of around 70 or as high as 75 indicates a limitation in intellectual functioning.
Adaptive Behavior: Adaptive behavior is the collection of conceptual, social, and practical skills that are learned and performed by people in their everyday lives.
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Conceptual skills—language and literacy; money, time, and number concepts; and self-direction.
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Social skills—interpersonal skills, social responsibility, self-esteem, gullibility, naïveté (i.e., wariness), social problem solving, and the ability to follow rules/obey laws and to avoid being victimized.
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Practical skills—activities of daily living (personal care), occupational skills, healthcare, travel/transportation, schedules/routines, safety, use of money, use of the telephone.
Standardized tests can also determine limitations in adaptive behavior.
Age of Onset : This condition is one of several developmental disabilities—that is, there is evidence of the disability during the developmental period, which is defined as before the age of 22.
- From the American Association on Intellectual and Developmental Disabilities (AAIDD)

Intellectual Disability in Children
Intellectual disability can be caused by a problem that starts any time before a child turns 18 years old – even before birth. It can be caused by injury, disease, or a problem in the brain. For many children, the cause of their intellectual disability is not known. Some of the most common known causes of intellectual disability – like Down syndrome, fetal alcohol syndrome, fragile X syndrome, genetic conditions, birth defects, and infections – happen before birth. Others happen while a baby is being born or soon after birth. Still other causes of intellectual disability do not occur until a child is older; these might include serious head injury, stroke, or certain infections.
What are some of the signs of intellectual disability?
Usually, the more severe the degree of intellectual disability, the earlier the signs can be noticed. However, it might still be hard to tell how young children will be affected later in life.
There are many signs of intellectual disability. For example, children with intellectual disability may:
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sit up, crawl, or walk later than other children
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learn to talk later, or have trouble speaking
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find it hard to remember things
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have trouble understanding social rules
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have trouble seeing the results of their actions
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have trouble solving problems
What can I do if I think my child may have intellectual disability?
Talk with your child’s doctor or nurse. If you or your doctor think there could be a problem, you can take your child to see a developmental pediatrician or other specialist, and you can contact your local early intervention agency (for children under 3) or public school (for children 3 and older). Wyoming residents can visit screenforsuccess.org for more resources from the Wyoming Department of Health.
From the Centers for Disease Control and Prevention (CDC). Please visit their website for additional information.