Hirvonen Jonni, Monto Simo, Wang Sheng H, Palva J Matias, Palva Satu
Helsinki Institute for Life Sciences, Neuroscience Center, University of Helsinki, Finland.
Netw Neurosci. 2018 Oct 1;2(4):442-463. doi: 10.1162/netn_a_00039. eCollection 2018.
Sensory-guided actions entail the processing of sensory information, generation of perceptual decisions, and the generation of appropriate actions. Neuronal activity underlying these processes is distributed into sensory, fronto-parietal, and motor brain areas, respectively. How the neuronal processing is coordinated across these brain areas to support functions from perception to action remains unknown. We investigated whether phase synchronization in large-scale networks coordinate these processes. We recorded human cortical activity with magnetoencephalography (MEG) during a task in which weak somatosensory stimuli remained unperceived or were perceived. We then assessed dynamic evolution of phase synchronization in large-scale networks from source-reconstructed MEG data by using advanced analysis approaches combined with graph theory. Here we show that perceiving and reporting of weak somatosensory stimuli is correlated with sustained strengthening of large-scale synchrony concurrently in delta/theta (3-7 Hz) and gamma (40-60 Hz) frequency bands. In a data-driven network localization, we found this synchronization to dynamically connect the task-relevant, that is, the fronto-parietal, sensory, and motor systems. The strength and temporal pattern of interareal synchronization were also correlated with the response times. These data thus show that key brain areas underlying perception, decision-making, and actions are transiently connected by large-scale dynamic phase synchronization in the delta/theta and gamma bands.
感觉引导的行为需要对感觉信息进行处理、做出感知决策并产生适当的行动。这些过程背后的神经元活动分别分布在感觉、额顶叶和运动脑区。神经元处理如何在这些脑区之间进行协调以支持从感知到行动的功能仍然未知。我们研究了大规模网络中的相位同步是否协调这些过程。在一项任务中，我们用脑磁图（MEG）记录了人类皮层活动，在该任务中，微弱的体感刺激要么未被感知到，要么被感知到。然后，我们通过使用结合图论的先进分析方法，从源重建的MEG数据评估大规模网络中相位同步的动态演变。在此我们表明，对微弱体感刺激的感知和报告与δ/θ（3 - 7赫兹）和γ（40 - 60赫兹）频段中大规模同步的持续增强相关。在数据驱动的网络定位中，我们发现这种同步动态地连接了与任务相关的额顶叶、感觉和运动系统。区域间同步的强度和时间模式也与反应时间相关。因此，这些数据表明，感知、决策和行动背后的关键脑区通过δ/θ和γ频段中的大规模动态相位同步短暂连接。
