Reading Disabilities With and Without Co-Occurring ADHD: No Evidence for Additive Impact on Reading Skills

Area of Science:

• Neuroscience
• Developmental Psychology
• Educational Psychology

Background:

• Reading disabilities (RD) and attention deficit/hyperactivity disorder (ADHD) frequently co-occur in children.
• Understanding the impact of this co-occurrence on reading outcomes and neural mechanisms is crucial for targeted interventions.

Purpose of the Study:

• To investigate if children with co-occurring RD and ADHD exhibit different reading outcomes compared to children with RD alone.
• To examine if the brain basis of word reading differs between children with RD and those with co-occurring RD and ADHD.

Main Methods:

• Two studies were conducted involving children aged 7-13.
• Study 1 included 175 children (RD, RD+ADHD, students without disabilities) who underwent literacy assessments and fMRI during a reading task.
• Study 2 replicated behavioral findings in a larger independent sample of over 2,100 children.

Main Results:

• Students without disabilities performed significantly better on all reading measures than groups with RD.
• No significant behavioral or functional brain activation differences were found between children with RD and those with RD+ADHD.
• Study 2 confirmed these behavioral findings, and children with ADHD only showed typical reading scores.

Conclusions:

• Co-occurring RD and ADHD is not associated with significantly greater reading impairment than RD alone.
• The neural underpinnings of word reading do not appear to be substantially different between these groups.
• These findings suggest that interventions for RD may be effective regardless of ADHD comorbidity.