What Are Borderline Developmental Disabilities?

Alfred Binet developed the first test that quantified intelligence. His idea of intelligence quotient (IQ) represented a ratio of mental age to chronological age. Today, IQ scores are measured in relationship to an average. Those with borderline developmental disabilities fall well below this average level of intelligence.

History

The first categories of low intelligence were "borderline deficient," "imbecile," and "idiot." Today's terms are more sensitive.

Caution

The term "borderline developmental disabilities" is considered pejorative. The existence of borderline personality disorder also makes the term unclear. The term "well below average" best describes this intelligence level.

Description

Those with well below average intelligence, or borderline developmental disabilities, have IQs between 70 and 80 points. They can perform activities of daily living (ADLs), such as hygiene upkeep tasks. Those with borderline developmental disabilities are separated from those with mental retardation by their IQ points and their levels of adaptive function. Individuals with well-below average intelligence live normal and independent lives.

Causes

Developmental disorders, such as autism, fetal alcohol syndrome, or Down syndrome can cause low intelligence and borderline developmental disabilities.

Treatments

Appropriate early intervention and special education are important keys that will raise the intelligence of a person who is well below average.

References

• Handbook of Psychological Assessment, Fifth Edition; Gary Groth-Marnet, Ph.D.; 2009
• IQ Testing