Date of Award


Degree Name

Master of Arts



First Advisor

Kibby, Michelle


The purposes of the present study were to determine which aspects of processing speed are affected in Attention-Deficit/Hyperactivity Disorder (ADHD) and which cognitive and motoric skills predict processing speed performance. Results indicated that children with ADHD performed slower than controls on perceptual and visual-motor speed measures (Symbol Search and Coding) but not on reaction time or cognitive speed measures (Simple Reaction Time and Decision Speed). Those with ADHD-PI were particularly affected. Verbal working memory predicted Symbol Search, Coding and Decision Speed performance, while graphomotor speed predicted Coding, and fine motor dexterity predicted Decision Speed. Thus, children with ADHD may struggle on tasks with greater perceptual and visual-motor demands, which may be related to the inattention dimension. Furthermore, this study provides further evidence for the relationship between working memory and processing speed, especially central executive involvement in processing speed. Other theoretical and clinical implications are discussed for classroom and clinic interventions.




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