Down Syndrome is an Intellectual Disability. But did you know?

Today, 21st March is observed globally as World Down Syndrome Day! Down Syndrome is a genetic disorder caused by the presence of all or part of an extra copy of chromosome 21. It is generally associated with physical growth delays, characteristic facial features, and mild to moderate intellectual disability.

I find it quite interesting that in many societies, including Nigeria where I live, there exists a significant number of individuals living with intellectual disabilities, yet very little is understood about them. Oftentimes, they have erroneously been tagged as "imbecile," or "mentally retarded."

Definition

The American Association on Intellectual and Developmental Disabilities (AAIDD) defines intellectual disability as, 

"a disability characterized by significant limitations both in intellectual functioning and in adaptive behaviour as expressed in conceptual, social, and practical adaptive skills. This disability originates before age 18."

From the definition, 2 deductions can be made as follows:

a.      Intellectual disability involves problems in adaptive behaviour, not just intellectual functioning.

b.     Persons with intellectual disability can improve (particularly,  those with mild intellectual disability).

Persons with intellectual disabilities are professionally classified as follows:

        a.      Mild (IQ of about 50 to 70)

        b.     Moderate (IQ of about 35 to 50)

        c.      Severe (IQ of about 20 to 35)

        d.     Profound (IQ below 20)

Causes and Identification

Some of the causes of intellectual disabilities are as follows:

a.      Chromosomal disorders such as in Down Syndrome.

b.     Disorders of brain formation.

c.      Maternal malnutrition during gestation.

d.     Fetal alcohol syndrome.

e.      Traumatic brain injury.

f.      Possible hereditary causes.

g.    Unstimulating adult-child interactions can also lead to mild intellectual disabilities.

Individuals with intellectual disabilities can be identified by assessments which combine individual IQ tests and adaptive behaviour measures. The IQ tests are used to assess intelligence while the adaptive behaviour usually involve the parents, teacher or other professional answering questions related to the individuals independence and daily living skills and maladaptive behaviour. (Hallahan, Kauffman, & Pullen, 2012).

Special Education for Learners with Intellectual Disabilities

Special education considerations for these individuals will be such that if the learner has a lower degree of intellectual disability, the teacher should emphasize academic skills. However, if the individual displays a higher degree of intellectual disability, emphasis should be on self-help, community living and vocational skills development.

When the intellectually disabled student is included in a regular classroom, teachers should plan creative ways to prevent the student from feeling socially isolated and becoming inattentive. Peer assisted learning (PAL) is a great way to achieve this goal.

As in most cases of developmental disabilities, early intervention programs can successfully improve the development of children with intellectual disabilities.