BACKGROUND & AIMS:
:Words forming a continuous story were presented to 9 subjects at frequencies ranging from 5 to 30 Hz, determined individually to render comprehension easy, effortful, or practically impossible. We identified a left-hemisphere neural network sensitive to reading performance directly from the time courses of activation in the brain, derived from magnetoencephalography data. Regardless of the stimulus rate, communication within the long-range neural network occurred at a frequency of 8-13 Hz. Our coherence-based detection of interconnected nodes reproduced several brain regions that have been previously reported as active in reading tasks, based on traditional contrast estimates. Intriguingly, the face motor cortex and the cerebellum, typically associated with speech production, and the orbitofrontal cortex, linked to visual recognition and working memory, additionally emerged as densely connected components of the network. The left inferior occipitotemporal cortex, involved in early letter-string or word-specific processing, and the cerebellum turned out to be the main forward driving nodes of the network. Synchronization within a subset of nodes formed by the left occipitotemporal, the left superior temporal, and orbitofrontal cortex was increased with the subjects' effort to comprehend the text. Our results link long-range neural synchronization and directionality with cognitive performance.
背景与目标:
: 形成连续故事的单词以5至30Hz的频率呈现给9个主题,分别确定以使理解变得容易,费力或几乎不可能。我们从脑磁图数据中直接从大脑激活的时间过程中确定了对阅读性能敏感的左半球神经网络。无论刺激速率如何,远程神经网络内的通信都以8-13Hz的频率发生。基于传统的对比估计,我们对互连节点的基于一致性的检测再现了几个大脑区域,这些区域以前被报道为在阅读任务中处于活动状态。有趣的是,通常与语音产生相关的面部运动皮层和小脑,以及与视觉识别和工作记忆相关的眶额皮层,还成为网络中紧密连接的组件。参与早期字母字符串或特定单词处理的左下枕颞叶皮层和小脑被证明是网络的主要向前驱动节点。随着受试者理解文本的努力,由左枕颞,左上颞和眶额叶皮层形成的节点子集内的同步增加。我们的结果将远程神经同步和方向性与认知表现联系起来。