There are many causes of intellectual disability, factors include physical, genetic and/or social. The most common syndromes associated with intellectual disability are autism, Down syndrome, Fragile X syndrome and Fetal Alcohol Spectrum Disorder (FASD).
In this manner, what are the different types of intellectual disability?
There are many types of intellectual disability which can involve difficulty communicating, learning, and retaining information.
- Fragile X syndrome (FXS) FXS is the most common known cause of an inherited intellectual disability worldwide.
- Developmental delay.
- Fetal alcohol spectrum disorder (FASD)
What is meant by the term intellectual disability?
Definition of Intellectual Disability. 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.
Levels of Intellectual Disability
|Profound||IQ 19 or below|
An intellectual disability, which used to be called mental retardation, is a psychological term for people with a very low IQ and problems with daily functioning. There are four levels of intellectual disability: mild, moderate, severe and profound.
Intellectual disability is a disability characterized by significant limitations both in intellectual functioning (reasoning, learning, problem solving) and in adaptive behavior, which covers a range of everyday social and practical skills. This disability originates before the age of 18.
Fragile X syndrome (FXS) is the most common inherited cause of intellectual disability worldwide. It is caused by a mutation of the FMR-1 (fragile-X mental retardation) gene located on the X chromosome.
Intellectual disability (ID), once called mental retardation, is characterized by below-average intelligence or mental ability and a lack of skills necessary for day-to-day living. People with intellectual disabilities can and do learn new skills, but they learn them more slowly.
Causes of intellectual disability can include:
- Infections (present at birth or occurring after birth)
- Chromosomal abnormalities (such as Down syndrome)
- Metabolic (such as hyperbilirubinemia, or very high bilirubin levels in babies)
- Nutritional (such as malnutrition)
An intellectual disability describes below-average IQ and a lack of skills needed for daily living. This condition used to be called “mental retardation.” A learning disability refers to weaknesses in certain academic skills. Reading, writing and math are the main ones.
Mild Intellectual Disability (MID) or Mild Mental Retardation. Intellectual Disability (formerly termed Mental Retardation) is an impairment of cognitive skills, adaptive life skills, and social skills. Individuals with IQs of less than 70-75 are considered Intellectually Disabled.
Many intellectual disabilities (ID, formerly mental retardation) are caused by genetic abnormalities. The two most common genetic causes of intellectual disabilities are Down syndrome and Fragile X syndrome. Down syndrome is the most common genetic origin of intellectual disabilities (ID, formerly mental retardation).
5 Most Common Learning Disabilities
- Dyslexia. Dyslexia is perhaps the best known learning disability.
- ADHD. Attention Deficit/Hyperactivity Disorder has affected more than 6.4 million children at some point.
- Dyscalculia. Math is another major area of concern when it comes to learning disabilities.
- Processing Deficits.
ASD stands for Autism Spectrum Disorder and can sometimes be referred to as Autistic Spectrum Disorder. In this text Autism and ASD mean the same. ASDs are any developmental disabilities that have been caused by a brain abnormality. A person with an ASD typically has difficulty with social and communication skills.
1 in 2 people with cerebral palsy have an intellectual disability. 1 in 5 people have a moderate to severe intellectual disability. Generally, the greater the level of a person's physical impairment, the more likely it is that they will have an intellectual disability.
Another distinction between Asperger's Disorder and autism concerns cognitive ability. While some individuals with autism have intellectual disabilities, by definition, a person with Asperger's Disorder cannot have a “clinically significant” cognitive delay, and most possess average to above-average intelligence.
It is not unusual for people with this disorder to become psychotic during depressive or manic episodes. Changes in a person's emotional or behavioural state are classic signs/symptoms of bipolar disorder. Refer to our information on 'Intellectual disability and depression'.
Common Conditions That Cause Disability
- Arthritis and other musculoskeletal problems. These are the most common causes of long-term disability.
- Heart disease and stroke. People may live with heart disease for years or decades.
- Mental health problems.
Some examples of common disabilities you may find are:
- vision Impairment.
- deaf or hard of hearing.
- mental health conditions.
- intellectual disability.
- acquired brain injury.
- autism spectrum disorder.
- physical disability.
Other disorders that may occur along with intellectual disabilities include attention deficit hyperactivity disorder (ADHD) and autism. Both of these disorders make can make learning and day-to-day life difficult, especially if compounded with intellectual disabilities.
The epidemiology of intellectual disability co-occurring with schizophrenia and other psychiatric illness is poorly understood. None the less, pervasive developmental disorder was more common among people with a dual diagnosis than among individuals with intellectual disability alone.
Some examples are below:
- Fragile X Syndrome. Fragile X is a genetic condition that affects a person's development, especially behavior and the ability to learn.
- Down Syndrome.
- Autism Spectrum Disorders.
- Other Intellectual Disabilities.
Sometimes intellectual disability is also referred to as developmental disability which is a broader term that includes ASD (autism spectrum disorders), epilepsy, cerebral palsy, developmental delay, fetal alcohol syndrome (or FASD) and other disorders that occur during the developmental period (birth to age 18).