Journal of Abnormal Child Psychology

, Volume 37, Issue 4, pp 521–534

Hyperactivity in Boys with Attention-Deficit/Hyperactivity Disorder (ADHD): A Ubiquitous Core Symptom or Manifestation of Working Memory Deficits?

  • Mark D. Rapport
  • Jennifer Bolden
  • Michael J. Kofler
  • Dustin E. Sarver
  • Joseph S. Raiker
  • R. Matt Alderson
Article

Abstract

Hyperactivity is currently considered a core and ubiquitous feature of attention-deficit/hyperactivity disorder (ADHD); however, an alternative model challenges this premise and hypothesizes a functional relationship between working memory (WM) and activity level. The current study investigated whether children’s activity level is functionally related to WM demands associated with the domain-general central executive and subsidiary storage/rehearsal components using tasks based on Baddeley’s (Working memory, thought, and action. New York: Oxford University Press 2007) WM model. Activity level was objectively measured 16 times per second using wrist- and ankle-worn actigraphs while 23 boys between 8 and 12 years of age completed control tasks and visuospatial/phonological WM tasks of increasing memory demands. All children exhibited significantly higher activity rates under all WM relative to control conditions, and children with ADHD (n = 12) moved significantly more than typically developing children (n = 11) under all conditions. Activity level in all children was associated with central executive but not storage/rehearsal functioning, and higher activity rates exhibited by children with ADHD under control conditions were fully attenuated by removing variance directly related to central executive processes.

Keywords

ADHD Working memory Hyperactivity Activity level Attention-deficit/hyperactivity disorder 

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Copyright information

© Springer Science+Business Media, LLC 2008

Authors and Affiliations

  • Mark D. Rapport
    • 1
  • Jennifer Bolden
    • 1
  • Michael J. Kofler
    • 1
  • Dustin E. Sarver
    • 1
  • Joseph S. Raiker
    • 1
  • R. Matt Alderson
    • 2
  1. 1.Department of PsychologyUniversity of Central FloridaOrlandoUSA
  2. 2.Department of PsychologyOklahoma State UniversityStillwaterUSA

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