Departments of Neurology, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520, United States; MOE Key Lab for Neuroinformation, High-Field Magnetic Resonance Brain Imaging Key Laboratory of Sichuan Province, School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu 610054, P R China.
Departments of Neurology, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520, United States.
Neuroimage. 2021 May 15;232:117873. doi: 10.1016/j.neuroimage.2021.117873. Epub 2021 Feb 27.
Studies of attention emphasize cortical circuits for salience monitoring and top-down control. However, subcortical arousal systems have a major influence on dynamic cortical state. We hypothesize that task-related increases in attention begin with a "pulse" in subcortical arousal and cortical attention networks, which are reflected indirectly through transient fMRI signals. We conducted general linear model and model-free analyses of fMRI data from two cohorts and tasks with mixed block and event-related design. 46 adolescent subjects at our center and 362 normal adults from the Human Connectome Project participated. We identified a core shared network of transient fMRI increases in subcortical arousal and cortical salience/attention networks across cohorts and tasks. Specifically, we observed a transient pulse of fMRI increases both at task block onset and with individual task events in subcortical arousal areas including midbrain tegmentum, thalamus, nucleus basalis and striatum; cortical-subcortical salience network regions including the anterior insula/claustrum and anterior cingulate cortex/supplementary motor area; in dorsal attention network regions including dorsolateral frontal cortex and inferior parietal lobule; as well as in motor regions including cerebellum, and left hemisphere hand primary motor cortex. The transient pulse of fMRI increases in subcortical and cortical arousal and attention networks was consistent across tasks and study populations, whereas sustained activity in these same networks was more variable. The function of the transient pulse in these networks is unknown. However, given its anatomical distribution, it could participate in a neuromodulatory surge of activity in multiple parallel neurotransmitter systems facilitating dynamic changes in conscious attention.
注意的研究强调了用于突显监测和自上而下控制的皮质回路。然而，皮质下唤醒系统对动态皮质状态有重大影响。我们假设与任务相关的注意力增加始于皮质下唤醒和皮质注意力网络的“脉冲”，这通过瞬态 fMRI 信号间接反映。我们对来自两个队列和具有混合块和事件相关设计的任务的 fMRI 数据进行了广义线性模型和无模型分析。我们中心的 46 名青少年受试者和人类连接组计划中的 362 名正常成年人参加了研究。我们确定了在队列和任务中，皮质下唤醒和皮质突显/注意力网络的瞬态 fMRI 增加的核心共享网络。具体来说，我们观察到在皮质下唤醒区域（包括中脑脑桥、丘脑、基底核和纹状体）以及皮质下-皮质突显网络区域（包括前岛叶/屏状核和前扣带皮层/辅助运动区）中，无论是在任务块开始时还是在单个任务事件中，都存在 fMRI 增加的瞬态脉冲；在背侧注意力网络区域（包括背外侧额皮质和下顶叶）以及运动区域（包括小脑和左手初级运动皮质）中也存在 fMRI 增加的瞬态脉冲。在跨任务和研究人群中，皮质下和皮质唤醒和注意力网络的 fMRI 增加的瞬态脉冲是一致的，而这些相同网络中的持续活动则更加多变。这些网络中瞬态脉冲的功能尚不清楚。然而，鉴于其解剖分布，它可能参与多个平行神经递质系统的活动的神经调节激增，从而促进意识注意力的动态变化。
