RD, ADHD, and their comorbidity from a dual route perspective.

In order to achieve further insight into the comorbidity of reading disorder (RD) and attention deficit/hyperactivity disorder (ADHD), lexical processing and rapid naming were studied in RD and ADHD. The Dual Route Cascaded model postulates that lexical processing contains two parallel processes: lexical route processing and sublexical route processing. An orthographic decision task and a phonological decision task were used to measure lexical and sublexical route processing, respectively.

Differential effects of atomoxetine on executive functioning and lexical decision in attention-deficit/hyperactivity disorder and reading disorder.

Objective: The effects of a promising pharmacological treatment for attention-deficit/hyperactivity disorder (ADHD), atomoxetine, were studied on executive functions in both ADHD and reading disorder (RD) because earlier research demonstrated an overlap in executive functioning deficits in both disorders. In addition, the effects of atomoxetine were explored on lexical decision.

Methods: Sixteen children with ADHD, 20 children with ADHD + RD, 21 children with RD, and 26 normal controls were enrolled in a randomized placebo-controlled crossover study.

How distinctive are ADHD and RD? Results of a double dissociation study.

The nature of the comorbidity between Attention-Deficit/Hyperactivity Disorder (ADHD) and Reading Disability (RD) was examined using a double dissociation design. Children were between 8 and 12 years of age and entered into four groups: ADHD only (n = 24), ADHD+RD (n = 29), RD only (n = 41) and normal controls (n = 26). In total, 120 children participated in the study; 38 girls and 82 boys.