If your child has an intellectual disability (ID), their brain hasn’t developed properly or has been injured in some way. Their brain may also not function within the normal range of both intellectual and adaptive functioning. In the past, medical professionals called this condition “mental retardation.”
There are four levels of ID:
Sometimes, ID may be classified as:
ID involves both a low IQ and problems adjusting to everyday life. There may also be learning, speech, social, and physical disabilities.
Severe cases of ID may be diagnosed soon after birth. However, you might not realize your child has a milder form of ID until they fail to meet common developmental goals. Almost all cases of ID are diagnosed by the time a child reaches 18 years of age.
Symptoms of ID will vary based on your child’s level of disability and may include:
- failure to meet intellectual milestones
- sitting, crawling, or walking later than other children
- problems learning to talk or trouble speaking clearly
- memory problems
- inability to understand the consequences of actions
- inability to think logically
- childish behavior inconsistent with the child’s age
- lack of curiosity
- learning difficulties
- IQ below 70
- inability to lead a fully independent life due to challenges communicating, taking care of themselves, or interacting with others
If your child has ID, they may experience some of the following behavioral issues:
- withdrawal from social activities
- attention-seeking behavior
- depression during adolescent and teen years
- lack of impulse control
- tendency toward self-injury
- low self-esteem
- low tolerance for frustration
- psychotic disorders
- difficulty paying attention
Some people with ID may also have specific physical characteristics. These can include having a short stature or facial abnormalities.
ID is divided into four levels, based on your child’s IQ and degree of social adjustment.
Mild intellectual disability
Some of the symptoms of mild intellectual disability include:
- taking longer to learn to talk, but communicating well once they know how
- being fully independent in self-care when they get older
- having problems with reading and writing
- social immaturity
- increased difficulty with the responsibilities of marriage or parenting
- benefiting from specialized education plans
- having an IQ range of 50 to 69
Moderate intellectual disability
If your child has moderate ID, they may exhibit some of the following symptoms:
- are slow in understanding and using language
- may have some difficulties with communication
- can learn basic reading, writing, and counting skills
- are generally unable to live alone
- can often get around on their own to familiar places
- can take part in various types of social activities
- generally having an IQ range of 35 to 49
Severe intellectual disability
Symptoms of severe ID include:
- noticeable motor impairment
- severe damage to, or abnormal development of, their central nervous system
- generally having an IQ range of 20 to 34
Profound intellectual disability
Symptoms of profound ID include:
- inability to understand or comply with requests or instructions
- possible immobility
- very basic nonverbal communication
- inability to care for their own needs independently
- the need of constant help and supervision
- having an IQ of less than 20
Other intellectual disability
People in this category are often physically impaired, have hearing loss, are nonverbal, or have a physical disability. These factors may prevent your child’s doctor from conducting screening tests.
Unspecified intellectual disability
If your child has an unspecified ID, they will show symptoms of ID, but their doctor doesn’t have enough information to determine their level of disability.
Doctors can’t always identify a specific cause of ID, but causes of ID can include:
- trauma before birth, such as an infection or exposure to alcohol, drugs, or other toxins
- trauma during birth, such as oxygen deprivation or premature delivery
- inherited disorders, such as phenylketonuria (PKU) or Tay-Sachs disease
- chromosome abnormalities, such as Down syndrome
- lead or mercury poisoning
- severe malnutrition or other dietary issues
- severe cases of early childhood illness, such as whooping cough, measles, or meningitis
- brain injury
To be diagnosed with ID, your child must have below-average intellectual and adaptive skills. Your child’s doctor will perform a three-part evaluation that includes:
- interviews with you
- observations of your child
- standard tests
Your child will be given standard intelligence tests, such as the Stanford-Binet Intelligence Test. This will help the doctor determine your child’s IQ.
The doctor may also administer other tests such as the Vineland Adaptive Behavior Scales. This test provides an assessment of your child’s daily living skills and social abilities, compared to other children in the same age group.
It’s important to remember that children from different cultures and socioeconomic statuses may perform differently on these tests. To form a diagnosis, your child’s doctor will consider the test results, interviews with you, and observations of your child.
Your child’s evaluation process might include visits to specialists, who may include a:
- speech pathologist
- social worker
- pediatric neurologist
- developmental pediatrician
- physical therapist
Laboratory and imaging tests may also be performed. These can help your child’s doctor detect metabolic and genetic disorders, as well as structural problems with your child’s brain.
Other conditions, such as hearing loss, learning disorders, neurological disorders, and emotional problems can also cause delayed development. Your child’s doctor should rule these conditions out before diagnosing your child with ID.
You, your child’s school, and your doctor will use the results of these tests and evaluations to develop a treatment and education plan for your child.
Your child will probably need ongoing counseling to help them cope with their disability.
You will get a family service plan that describes your child’s needs. The plan will also detail the services that your child will need to help them with normal development. Your family needs will also be addressed in the plan.
When your child is ready to attend school, an Individualized Education Program (IEP) will be put in place to help them with their educational needs. All children with ID benefit from special education.
The federal Individuals with Disabilities Act (IDEA) requires that public schools provide free and appropriate education to children with ID and other developmental disabilities.
The main goal of treatment is to help your child reach their full potential in terms of:
- social skills
- life skills
Treatment may include:
- behavior therapy
- occupational therapy
- medication, in some cases
When ID occurs with other serious physical problems, your child may have a below-average life expectancy. However, if your child has mild to moderate ID, they will probably have a fairly normal life expectancy.
When your child grows up, they may be able to work a job that complements their level of ID, live independently, and support themselves.
Support services are available to help adults with ID live independent and fulfilling lives.