Rapport Mark D, Bolden Jennifer, Kofler Michael J, Sarver Dustin E, Raiker Joseph S, Alderson R Matt
Department of Psychology, University of Central Florida, Orlando, FL, USA.
J Abnorm Child Psychol. 2009 May;37(4):521-34. doi: 10.1007/s10802-008-9287-8.
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.
多动目前被认为是注意力缺陷多动障碍（ADHD）的一个核心且普遍存在的特征；然而，另一种模型对这一前提提出了挑战，并假设工作记忆（WM）与活动水平之间存在功能关系。本研究使用基于巴德利（《工作记忆、思维与行动》。纽约：牛津大学出版社，2007年）WM模型的任务，调查了儿童的活动水平是否与与领域通用的中央执行系统及辅助存储/复述组件相关的WM需求存在功能关系。使用佩戴在手腕和脚踝上的活动记录仪每秒客观测量16次活动水平，同时23名8至12岁的男孩完成了控制任务以及记忆需求不断增加的视觉空间/语音WM任务。与控制条件相比，所有儿童在所有WM条件下的活动率均显著更高，并且患有ADHD的儿童（n = 12）在所有条件下的活动量均显著多于发育正常的儿童（n = 11）。所有儿童的活动水平与中央执行系统功能相关，但与存储/复述功能无关，并且通过去除与中央执行过程直接相关的方差，患有ADHD的儿童在控制条件下表现出的较高活动率完全减弱。
