Metin Baris, Krebs Ruth M, Wiersema Jan R, Verguts Tom, Gasthuys Roos, van der Meere Jacob J, Achten Eric, Roeyers Herbert, Sonuga-Barke Edmund
Department of Experimental-Clinical and Health Psychology, Ghent University.
Department of Experimental Psychology, Ghent University.
J Abnorm Psychol. 2015 Feb;124(1):208-214. doi: 10.1037/abn0000013. Epub 2014 Oct 13.
The state regulation deficit model posits that individuals with attention-deficit/hyperactivity disorder (ADHD) have difficulty applying mental effort effectively under suboptimal conditions such as very fast and very slow event rates (ERs). ADHD is also associated with diminished suppression of default mode network (DMN) activity and related performance deficits on tasks requiring effortful engagement. The current study builds on these 2 literatures to test the hypothesis that failure to modulate DMN activity in ADHD might be especially pronounced at ER extremes. Nineteen adults with ADHD and 20 individuals without any neuropsychiatric condition successfully completed a simple target detection task under 3 ER conditions (2-, 4-, and 8-s interstimulus intervals) inside the scanner. Task-related DMN deactivations were compared between 2 groups. There was a differential effect of ER on DMN activity for individuals with ADHD compared to controls. Individuals with ADHD displayed excessive DMN activity at the fast and slow, but not at the moderate ER. The results indicate that DMN attenuation in ADHD is disrupted in suboptimal energetic states where additional effort is required to optimize task engagement. DMN dysregulation may be an important element of the neurobiological underpinnings of state regulation deficits in ADHD.
状态调节缺陷模型认为，患有注意力缺陷多动障碍（ADHD）的个体在诸如非常快和非常慢的事件发生率（ERs）等非最佳条件下难以有效地运用心理努力。ADHD还与默认模式网络（DMN）活动抑制减弱以及在需要努力参与的任务上相关的表现缺陷有关。当前的研究基于这两方面的文献来检验以下假设：在ADHD中，未能调节DMN活动在ER极端情况下可能尤为明显。19名患有ADHD的成年人和20名没有任何神经精神疾病的个体在扫描仪内的3种ER条件下（刺激间隔为2秒、4秒和8秒）成功完成了一项简单的目标检测任务。对两组之间与任务相关的DMN失活进行了比较。与对照组相比，ER对患有ADHD的个体的DMN活动有不同的影响。患有ADHD的个体在快速和慢速ER时表现出过度的DMN活动，但在中等ER时则没有。结果表明，在需要额外努力来优化任务参与的非最佳能量状态下，ADHD中DMN的减弱受到干扰。DMN失调可能是ADHD状态调节缺陷的神经生物学基础的一个重要因素。
