Department of Psychiatry & Behavioral Sciences, Stanford University School of Medicine, Stanford, California.
Department of Psychiatry & Behavioral Sciences, Stanford University School of Medicine, Stanford, California.
Biol Psychiatry Cogn Neurosci Neuroimaging. 2018 Mar;3(3):263-273. doi: 10.1016/j.bpsc.2017.10.005. Epub 2017 Nov 7.
Attention-deficit/hyperactivity disorder (ADHD) is thought to stem from aberrancies in large-scale cognitive control networks. However, the exact nature of aberrant brain circuit dynamics involving these control networks is poorly understood. Using a saliency-based triple-network model of cognitive control, we tested the hypothesis that dynamic cross-network interactions among the salience, central executive, and default mode networks are dysregulated in children with ADHD, and we investigated how these dysregulations contribute to inattention.
Using functional magnetic resonance imaging data from 140 children with ADHD and typically developing children from two cohorts (primary cohort = 80 children, replication cohort = 60 children) in a case-control design, we examined both time-averaged and dynamic time-varying cross-network interactions in each cohort separately.
Time-averaged measures of salience network-centered cross-network interactions were significantly lower in children with ADHD compared with typically developing children and were correlated with severity of inattention symptoms. Children with ADHD displayed more variable dynamic cross-network interaction patterns, including less persistent brain states, significantly shorter mean lifetimes of brain states, and intermittently weaker cross-network interactions. Importantly, dynamic time-varying measures of cross-network interactions were more strongly correlated with inattention symptoms than with time-averaged measures of functional connectivity. Crucially, we replicated these findings in the two independent cohorts of children with ADHD and typically developing children.
Aberrancies in time-varying engagement of the salience network with the central executive network and default mode network are a robust and clinically relevant neurobiological signature of childhood ADHD symptoms. The triple-network neurocognitive model provides a novel, replicable, and parsimonious dynamical systems neuroscience framework for characterizing childhood ADHD and inattention.
注意力缺陷多动障碍（ADHD）被认为源于大规模认知控制网络的异常。然而，涉及这些控制网络的异常脑回路动力学的具体性质还了解甚少。我们使用基于突显的认知控制三网络模型，检验了 ADHD 儿童的突显、中央执行和默认模式网络之间的跨网络相互作用存在动态失调的假设，并研究了这些失调如何导致注意力不集中。
我们采用病例对照设计，使用来自两个队列的 140 名 ADHD 儿童和发育正常的儿童的功能磁共振成像数据（主要队列=80 名儿童，复制队列=60 名儿童），分别在每个队列中检查了时间平均和动态时变的跨网络相互作用。
与发育正常的儿童相比，ADHD 儿童的突显网络为中心的跨网络相互作用的时间平均测量值明显较低，并且与注意力不集中症状的严重程度相关。ADHD 儿童显示出更可变的动态跨网络相互作用模式，包括更少的持久脑状态、脑状态的平均寿命显著缩短以及间歇性的跨网络相互作用减弱。重要的是，与功能连接的时间平均测量值相比，跨网络相互作用的动态时变测量值与注意力不集中症状的相关性更强。至关重要的是，我们在两个独立的 ADHD 儿童和发育正常的儿童队列中复制了这些发现。
突显网络与中央执行网络和默认模式网络之间时变的参与异常是儿童 ADHD 症状的一种稳健且具有临床意义的神经生物学特征。三网络神经认知模型为描述儿童 ADHD 和注意力不集中提供了一种新颖、可复制和简约的动力系统神经科学框架。
