Institute for Brain and Psychological Sciences, Sichuan Normal University, Chengdu 610066, China.
The Clinical Hospital of Chengdu Brain Science Institute, MOE Key Lab for Neuroinformation, School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu 611731, China.
Neuroscience. 2019 Dec 1;422:172-183. doi: 10.1016/j.neuroscience.2019.10.024. Epub 2019 Nov 6.
Low frequency phase synchronization is an essential mechanism of information communication among brain regions. In the infra-slow frequency range (<0.1 Hz), inter-regional phase lag is of importance for brain function (e.g., anti-phase between the default mode network and task positive network). However, the role of phase lag in cognitive processing remains unclear. Based on the frequency tagging experimental paradigm and functional magnetic resonance imaging (fMRI) technique, we investigated inter-regional phase lag and phase coherence using a face recognition task (n = 30, 15 males/15 females). Phase coherence within the face processing system was significantly increased during task state, highlighting the importance of regular inter-regional phase relationship for face recognition. Moreover, results showed decreased phase lag within the core and extended face areas (face processing system) and increased phase lag between the face processing system and frontoparietal network, indicating a reorganization of inter-regional relationships of the two systems. Inter-regional phase lag was modulated by the task at ascending and descending phases of the fMRI signal, suggesting a phase-dependent inter-regional relationship. Furthermore, phase lags between visual cortex and amygdala and between visual cortex and motor area were positively related to reaction time, indicating better task performance depends on both rapid emotional detection pathway and visual-motor pathway. Overall, inter-regional phase synchronization in the infra-slow frequency range is of important for effective information communication and cognitive performance.
低频相位同步是大脑区域之间信息交流的一个基本机制。在亚慢频率范围内（<0.1 Hz），区域间的相位滞后对于大脑功能很重要（例如，默认模式网络和任务正网络之间的反相）。然而，相位滞后在认知处理中的作用仍不清楚。基于频率标记实验范式和功能磁共振成像（fMRI）技术，我们使用面孔识别任务（n=30，15 名男性/15 名女性）研究了区域间的相位滞后和相位相干性。在任务状态下，面孔处理系统内的相位相干性显著增加，突出了区域间规则相位关系对面孔识别的重要性。此外，结果显示核心和扩展的面孔区域（面孔处理系统）内的相位滞后减小，面孔处理系统和额顶网络之间的相位滞后增加，表明两个系统的区域间关系发生了重新组织。区域间相位滞后受到 fMRI 信号上升和下降阶段任务的调节，表明存在与相位相关的区域间关系。此外，视皮层和杏仁核之间以及视皮层和运动区之间的相位滞后与反应时间呈正相关，表明更好的任务表现取决于快速的情绪检测通路和视觉-运动通路。总的来说，亚慢频率范围内的区域间相位同步对于有效的信息交流和认知表现很重要。
