Word Reading and Attention-Deficit/Hyperactivity Disorder in Children With Developmental Language Disorder

Area of Science:

• Child Psychology
• Neurodevelopmental Disorders
• Educational Psychology

Background:

• Developmental Language Disorder (DLD) affects language acquisition and is often comorbid with other neurodevelopmental conditions.
• Attention-deficit/hyperactivity disorder (ADHD) is characterized by inattention and/or hyperactivity-impulsivity, frequently co-occurring with learning difficulties.
• Dyslexia, a specific learning difficulty in reading, shares some cognitive-linguistic mechanisms with DLD and ADHD, necessitating a nuanced understanding of their interplay.

Purpose of the Study:

• To investigate the relationship between word reading and ADHD symptoms in school-aged children with and without DLD.
• To examine the mediating roles of phonological memory (associated with dyslexia) and working memory (associated with ADHD) in this relationship.
• To develop and test a novel model (RE.A.L. Comorbidity Model) for understanding these complex associations.

Main Methods:

• A sample of 420 second and third graders was screened, with 46 confirmed DLD cases and 76 typically developing children identified.
• Participants underwent assessments for language abilities, word reading, ADHD symptoms, nonverbal intelligence, working memory, and phonological memory.
• Statistical models were employed to analyze the associations and mediations between these variables, including a novel comorbidity model.

Main Results:

• Phonological memory was consistently associated with word reading across all models.
• Working memory was uniquely associated with ADHD symptoms.
• The RE.A.L. Comorbidity Model demonstrated that phonological memory uniquely mediated the relationship between DLD and word reading difficulties, independent of ADHD symptoms.

Conclusions:

• Cognitive-linguistic indices, specifically phonological memory, play a unique and crucial role in word reading abilities among children with DLD.
• ADHD symptoms, while associated with working memory deficits, did not directly predict poor word reading in this population.
• These findings underscore the importance of assessing cognitive-linguistic profiles, including dyslexia- and ADHD-associated mechanisms, when evaluating word reading and ADHD symptoms in children with DLD.