Department of Psychology, Children's National Medical Center, Washington, DC.
Department of Psychology, Children's National Medical Center, Washington, DC; Interdisciplinary Program in Neuroscience, Georgetown University, Children's National Medical Center, Washington, DC.
Biol Psychiatry Cogn Neurosci Neuroimaging. 2017 Sep;2(6):537-545. doi: 10.1016/j.bpsc.2017.03.008. Epub 2017 Mar 18.
Comorbid executive dysfunction in autism spectrum disorder (ASD) is a barrier to adaptive functioning, despite remittance of core social-communication symptoms. Network models of ASD address core symptoms but not comorbid executive dysfunction. Following recent demonstrations in healthy adults that, with increasing executive demands, hubs embedded within frontoparietal-insular control networks interact with a more diverse set of networks, we hypothesized that the capability of hubs to do so is perturbed in ASD and predicts executive behavior.
Seventy-five 7- to 13-year-old children with ASD (n = 35) and age- and IQ-matched typically developing control subjects (n = 40) completed both a resting-state and a selective attention task functional magnetic resonance imaging session. We assessed changes in the participation coefficient, a graph theory metric indexing hubness, of 264 brain regions comprising 12 functional networks between the two sessions. Parent reported executive impairment in everyday life was measured using the Behavior Rating Inventory of Executive Function.
The participation coefficient of the frontoparietal-insular cortex, including core nodes of the frontoparietal control and salience networks, significantly increased in typically developing children but not in children with ASD during the task relative to rest. Change in frontoparietal-insular participation coefficient predicted Behavior Rating Inventory of Executive Function scores indexing the ability to attend to task-oriented output, plan and organize, and sustain working memory.
Our results suggest that executive impairments in ASD emerge from a failure of frontoparietal-insular control regions to function as adaptive and integrative hubs in the brain's functional network architecture. Our results also demonstrate the utility of examining dynamic network function for elucidating potential biomarkers for disorders with comorbid executive dysfunction.
自闭症谱系障碍（ASD）中合并存在的执行功能障碍是适应功能的障碍，尽管核心社交-沟通症状已经缓解。ASD 的网络模型解决了核心症状，但没有解决合并存在的执行功能障碍。最近在健康成年人中证明，随着执行需求的增加，额顶-岛叶-扣带回控制网络内的枢纽与更多不同的网络相互作用，我们假设，这种枢纽的能力在 ASD 中受到干扰，并预测执行行为。
75 名 7 至 13 岁的 ASD 儿童（n = 35）和年龄和智商匹配的典型发育对照组儿童（n = 40）完成了静息态和选择性注意任务功能磁共振成像（fMRI）扫描。我们评估了两个时间段之间 12 个功能网络中包含的 264 个脑区的参与系数（一种度量网络枢纽度的图论指标）的变化。使用行为评定量表评估了日常生活中的执行功能损害。
与静息状态相比，在任务期间，典型发育儿童的额顶-岛叶-扣带回皮层的参与系数显著增加，包括额顶控制和突显网络的核心节点，而 ASD 儿童则没有增加。额顶-岛叶参与系数的变化预测了行为评定量表中索引任务导向输出、计划和组织以及维持工作记忆的执行功能评分。
我们的结果表明，ASD 中的执行功能障碍是由于额顶-岛叶-扣带回控制区域无法作为大脑功能网络架构中的适应性和整合枢纽而出现的。我们的结果还表明，检查动态网络功能对于阐明具有合并执行功能障碍的疾病的潜在生物标志物具有实用价值。
