title: Nonword reading and Stroop interference: what differentiates attention-deficit/hyperactivity disorder and reading disability?
abstract: BACKGROUND
  Attention deficits and impaired reading performance co-occur more often than expected by chance; however, the underlying mechanism of this association still remains rather unexplored.
  
  
  METHODS
  In two consecutive studies, children aged 8 to 12 years with attention-deficit/hyperactivity disorder (ADHD) and children with reading disability (RD) were examined using a 2 (ADHD versus no ADHD) × 2 (RD versus no RD) factorial design. To further delineate deficient interference control from reading processes, we used a newly developed self-paced word/nonword reading task (Experiment 1, n = 68) and a modified computerized Stroop paradigm, including an orthographic phonological neighbor (OPN) condition (Experiment 2, n = 84).
  
  
  RESULTS
  RD (compared to non-RD groups) was associated with impairments in both word and nonword reading, while children with ADHD also showed impaired nonword reading. In the Stroop task, RD, but not ADHD, had a significant impact on task performance. Interestingly, a significant interaction between ADHD, RD, and task condition emerged, which was due to particularly slower reaction times to nonwords in children with RD only, while task performance in children with comorbid ADHD and RD resembled that of ADHD only.
  
  
  CONCLUSIONS
  Thus, our results demonstrate that impairments in nonword reading were not specific to RD but were also present in children with ADHD. In addition, RD and not ADHD was characterized by poor interference control in the Stroop task. These findings question whether unique cognitive deficits are specific to either ADHD or RD.
authors: a Department of Child and Adolescent Mental Health , University of Erlangen , Erlangen , Germany.
authors: Christa
authors: C
authors: Stubenrauch
authors: Juliane
authors: J
authors: Freund
authors: Simone
authors: S
authors: Alecu de Flers
authors: Simone
authors: S
authors: DeFlers
authors: Wolfgang
authors: W
authors: Scharke
authors: Mario
authors: M
authors: Braun
authors: Arthur M
authors: AM
authors: Jacobs
authors: Kerstin
authors: K
authors: Konrad
mesh_terms: D000704:Analysis of Variance; D001289:Attention Deficit Disorder with Hyperactivity / Q000150:complications / Q000175:diagnosis*; D002648:Child; D004410:Dyslexia / Q000150:complications / Q000175:diagnosis*; D005260:Female; D006801:Humans; D008297:Male; D011930:Reaction Time; D011932:Reading; D057190:Stroop Test; D014825:Vocabulary