Functional Disconnection of Frontal Cortex and Visual Cortex in Attention-Deficit/Hyperactivity Disorder
Functional Disconnection of Frontal Cortex and Visual Cortex in Attention-Deficit/Hyperactivity Disorder
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DOI：
10.1016/j.biopsych.2009.11.022
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发表时间：
2010-04-01
影响因子：
10.6
通讯作者：
Corbett, Blythe A.
中科院分区：
文献类型：
--
作者：
Mazaheri, Ali;Coffey-Corina, Sharon;Corbett, Blythe A.
背景：当前注意缺陷/多动障碍（ADHD）的病理生理模型表明，大脑注意网络内功能连接受损可能导致该疾病。在这项脑电图（EEG）研究中，我们分析了交叉频率振幅相关性，以研究线索诱导的功能连接在正常发育儿童和ADHD儿童中的差异。方法：记录25名8 - 12岁儿童（14名ADHD）在执行一项跨模态注意任务时的脑电图活动。（概率）即将到来的目标的形态。计算被试在提示后和目标前1秒的θ (3-5 Hz)和α (8-12 Hz)频段的功率谱。结果：两组被试均表现出预测性注意线索的行为优势，对有效提示目标（视觉前提示预测视觉目标）的反应比无效提示目标（视觉前提示预测听觉目标）的反应更快、更准确；此外，与线索目标效度无关，典型儿童的总体反应速度更快。在发育正常的儿童中，α活动受到两种线索的差异调节，与中额波活动呈负相关；这些与注意力控制相关的脑电图在ADHD儿童中没有观察到。结论：我们的研究结果为ADHD儿童自上而下注意力控制的特定缺陷提供了神经生理学证据，该缺陷表现为额叶和枕叶皮层之间的功能断开。
Background: Current pathophysiologic models of attention-deficit/hyperactivity disorder (ADHD) suggest that impaired functional connectivity within brain attention networks may contribute to the disorder. In this electroencephalographic (EEG) study, we analyzed cross-frequency amplitude correlations to investigate differences in cue-induced functional connectivity in typically developing children and children with ADHD.Methods: Electroencephalographic activity was recorded in 25 children aged 8 to 12 years (14 with ADHD) while they performed a cross-modal attention task in which cues signaled the most likely (.75 probability) modality of an upcoming target. The power spectra of the EEG in the theta (3-5 Hz) and alpha (8-12 Hz) bands were calculated for the 1-sec interval after the cue and before the target while subjects prepared to discriminate the expected target.Results: Both groups showed behavioral benefits of the predictive attentional cues, being faster and more accurate for validly cued targets (e.g., visual target preceded by a cue predicting a visual target) than to invalidly cued targets (e.g., visual target preceded by a cue predicting an auditory target); in addition, independent of cue-target validity, typical children were faster to respond overall. In the typically developing children, the alpha activity was differentially modulated by the two cues and anticorrelated with midfrontal theta activity; these EEG correlates of attentional control were not observed in the children with ADHD.Conclusions: Our findings provide neurophysiological evidence for a specific deficit in top-down attentional control in children with ADHD that is manifested as a functional disconnection between frontal and occipital cortex.