What is an intellectual disability?

An intellectual disability is a condition and not an illness. People do not suffer from an intellectual disability; they present or have an intellectual disability. They live with this condition.

Three equally important criteria must be present for a diagnosis of intellectual disability to be made:

  • Significant limitations in intellectual functioning, for example, when the person has a hard time understanding abstract concepts or anticipating the consequences of an action.
  • Limitations in adaptive behaviour that can result in shortfalls in terms of conceptual, social and practical skills:
    • handling concepts related to money
    • engaging in social interactions
    • performing day-to-day activities and personal care (meals, domestic tasks, transportation, getting dressed, etc.)
  • These limitations must be observed before age 18.

Only specialists who are members of a professional order (psychologists, neuro-psychologists) can diagnose an intellectual disability, using recognized standardized tests, according to applicable standards of practice.

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What are the characteristics of an intellectual disability?

Everyone with an intellectual disability is different, but certain common characteristics can be present. These can include difficulties with:

  • Locating themselves in time and space
  • Short-term memory
  • Language development
  • Concentration
  • Problem solving
  • Maintaining and generalizing newly acquired strategies
  • Logical connections between things or events
How many people have an intellectual disability?

Intellectual disability is the most widespread developmental disorder among the general population. In Quebec, around 82,000 people (2014 data) have an intellectual disability, or close to 1% of the population.

What are the causes of intellectual disability?

An intellectual disability can occur following an attack on the central nervous system. But intellectual disabilities do not always have a single cause. Causes include genetic conditions and heredity. In addition to these biological factors, there are also psycho-affective and environmental factors.

  • Genetic factors
    • Trisomy 13, 18, 21
    • Prader-Willi syndrome
    • Fragile X syndrome
  • Environmental factors
    • Congenital infections
    • Fetal alcoholism
    • Exposure to drugs and toxins
    • Placental insufficiency
    • Problems during childbirth, such as a lack of oxygen, infection (meningitis) and poisoning (lead)
When does an intellectual disability occur?

Conditions that result in an intellectual disability can occur at conception, at birth or during childhood. An intellectual disability always appears before age 18.

Can an intellectual disability be cured?

Intellectual disability is not an illness, so it cannot be cured. However, with support, stimulation and an adapted environment, people can become more autonomous.

Is intellectual disability a mental health problem?

These two conditions should not be confused, although they may coexist in certain people. Just like anyone else, people with an intellectual disability can be affected by psychological problems such as emotional, behavioural, affective, anxiety-related or personality problems. However, this coexistence is not found systematically in people with an intellectual disability.

How should I act around someone with an intellectual disability?

Less is generally more. Act as you would with anyone else. Also keep in mind that simple gestures that show kindness and composure are often a good starting point.

Communicate with the person. Speak to the person directly rather than the person accompanying him or her, if anyone is. Speak normally without infantilizing the person. Use short sentences to maximize understanding. As needed, use visual tools and gestures. Ask closed questions, which can be answered with a yes or no.

Be patient. Give the person time to assimilate the information and answer. As needed, reword or speak more slowly and ask whether the person understood.

Encourage autonomy. Don’t do things for the person, but offer your help.

Don’t judge. Don’t make assumptions about the person’s abilities or inabilities. Don’t pass judgement on choices that may not reflect the person’s age group, for example, if an adult with an intellectual disability wears a shirt that would typically be for a child.

Follow the person’s pace, whether in getting around or in conversation.

And, lastly, always be respectful.

People have strengths and limitations. Not seeing strengths means not seeing the flip side of the coin.

How can I help people with an intellectual disability thrive?
  • Introduce yourself.
  • Introduce the people around you.
  • Ask about the person’s interests.
  • Suggest activities or tasks that interest the person and that tap into his or her strengths and abilities.
  • Talk time to talk to the person.
  • Use positive reinforcement.