Common Genetic Influences for ADHD and Reading Disability

Author: Elsevier
Published: 2010/12/08 - Updated: 2023/01/04
Peer Reviewed Publication: Yes
Topic: ADHD and ADD - Publications List

Page Content: Synopsis - Introduction - Main

Synopsis: Attention Deficit Hyperactivity Disorder (ADHD) and developmental reading disability (RD) are complex childhood disorders that frequently occur together. The findings showed that both RD and ADHD are complex disorders influenced by many factors; ADHD was associated with a reduced ability to inhibit responses to stimuli, while reading disabilities were related to various weaknesses in language and memory.

Defining Attention Deficit Hyperactivity Disorder (ADHD)

Attention Deficit Hyperactivity Disorder (ADHD): Attention deficit hyperactivity disorder (ADHD) is a neurodevelopmental disorder characterized by excessive inattention, hyperactivity, and impulsivity that are pervasive, impairing in multiple contexts, and otherwise age-inappropriate. ADHD is associated with other neurodevelopmental and mental disorders and some non-psychiatric disorders, which can cause additional impairment, especially in modern society. Adult ADHD can lead to unstable relationships, poor work or school performance, low self-esteem, and other problems. Treatment for adult ADHD is similar to treatment for childhood ADHD. Adult ADHD treatment includes medications, psychological counseling (psychotherapy), and therapy for any mental health conditions that occur along with ADHD.

Introduction

Attention Deficit Hyperactivity Disorder (ADHD) and developmental reading disability (RD) are complex childhood disorders that frequently occur together; if a child is experiencing trouble with reading, symptoms of ADHD are often also present. However, the reason for this correlation remains unknown.

Main Item

A new study reported in the latest special issue of Cortex (www.sciencedirect.com/science/journal/00109452), dedicated to "Developmental Dyslexia and Dysgraphia," has suggested that the disorders have common genetic influences, which may also lead to slow processing speed - the brain taking longer to make sense of the information it receives.

The researchers looked at 457 pairs of twins from the Colorado Learning Disabilities Research Center (CLDRC) twin study - an ongoing study of the causes of reading disabilities, ADHD, and related disorders.

Dr. Erik Willcutt and colleagues compared groups of participants with and without RD and ADHD, using a variety of tests to measure general cognitive ability, processing speed, reading, and language skills, and then analyzed results from pairs of twins within those groups to determine the genetic causes of any correlations.

The use of identical twins, who share all their genes, and non-identical twins, who share only half their genes, allowed the researchers to distinguish between genetic and environmental influences on the participants' cognitive abilities.

The findings showed that both RD and ADHD are complex disorders influenced by many factors; ADHD was associated with a reduced ability to inhibit responses to stimuli while reading disabilities were associated with various weaknesses in language and memory.

However, both disorders were associated with a slow processing speed, and the twin analyses further revealed a significant genetic correlation between RD and ADHD, i.e., a participant with one of the disorders was more likely to show symptoms of the other.

The authors of the study suggest that processing efficiency may be a useful marker in future studies of the connection between the two disorders.

Attribution/Source(s): This peer reviewed publication was selected for publishing by the editors of Disabled World (DW) due to its relevance to the disability community. Originally authored by Elsevier and published on 2010/12/08, this content may have been edited for style, clarity, or brevity. For further details or clarifications, Elsevier can be contacted at elsevier.com NOTE: Disabled World does not provide any warranties or endorsements related to this article.