American Board of Psychiatry and Neurology (ABPN) Practice Exam 2026 - Free ABPN Practice Questions and Study Guide

Intellectual disability is primarily characterized by significant limitations in both intellectual functioning and adaptive behaviors, which are necessary for daily living. The key features include:

- Deficits in reasoning (first option) is a hallmark of intellectual disability, as individuals typically exhibit lower intellectual functioning that affects their ability to think, reason, and solve problems.

- Deficits in adaptive functioning (second option) is also a core component. This refers to challenges in everyday skills, including communication, self-care, and social skills that are necessary for participation in typical daily life.

- Onset during childhood development (fourth option) is another defining characteristic, as intellectual disabilities are recognized to emerge during the developmental period, meaning that symptoms become evident before the age of 18.

In contrast, deficits in social-emotional reciprocity (third option) are not universally required for diagnosing intellectual disability. While individuals with intellectual disabilities may experience challenges in social interactions, these challenges do not necessarily involve social-emotional reciprocity as defined in conditions such as autism spectrum disorder. Therefore, this aspect does not characterize all individuals with intellectual disability and can vary widely among those affected, making it the correct answer.