Department of Neurosurgery, The University of Tokyo, Tokyo, Japan.
Clin Neurophysiol. 2013 Jan;124(1):91-100. doi: 10.1016/j.clinph.2012.06.006. Epub 2012 Jul 12.
We developed a novel technique of spatial normalization of subdural electrode positions across subjects and assessed the spatial-temporal dynamics of high-gamma activity (HGA) in the dominant hemisphere elicited by three distinct language tasks.
The normalization process was applied to 1512 subdural electrodes implanted in 21 patients with intractable epilepsy. We projected each task-related HGA profile onto a normalized brain.
The word interpretation task initially elicited HGA augmentation in the bilateral fusiform gyri at 100 ms after stimulus onsets, subsequently in the left posterior middle temporal gyrus, in the left ventral premotor cortex at 200 ms and in the left middle and left inferior frontal gyri at 300 ms and after. The picture naming task elicited HGA augmentation in few sites in the left frontal lobe. The verb generation task elicited HGA in the left superior temporal gyrus at 100-600 ms. Common HGA augmentation elicited by all three tasks was noted in the left posterior-middle temporal and left ventral premotor cortices.
The spatial-temporal dynamics of language-related HGA were demonstrated on a spatially-normalized brain template.
This study externally validated the spatial and temporal dynamics of language processing suggested by previous neuroimaging and electrophysiological studies.
我们开发了一种新的技术，用于对不同受试者的硬脑膜下电极位置进行空间归一化，并评估了三种不同语言任务诱发的优势半球高伽马活动（HGA）的时空动力学。
归一化过程应用于 21 名难治性癫痫患者植入的 1512 个硬脑膜下电极。我们将每个与任务相关的 HGA 分布投射到归一化的大脑上。
单词解释任务最初在刺激开始后 100ms 时在双侧梭状回引起 HGA 增强，随后在左后颞中回、左腹侧运动前皮质在 200ms 时和左中回和左下回在 300ms 时以及之后引起 HGA 增强。图片命名任务仅在左额叶的几个部位引起 HGA 增强。动词生成任务在 100-600ms 时在左颞上回引起 HGA。所有三个任务共同引起的 HGA 增强在左后-中颞叶和左腹侧运动前皮质。
在空间归一化的大脑模板上展示了语言相关 HGA 的时空动力学。
这项研究对外验证了先前神经影像学和电生理学研究提出的语言处理的空间和时间动力学。
