Gow David W, Keller Corey J, Eskandar Emad, Meng Nate, Cash Sydney S
Department of Neurology, Cognitive/Behavioral Neurology Group, Massachusetts General Hospital, 175 Cambridge Street, Suite S340, Boston, MA 02114, United States.
Brain Lang. 2009 Jul;110(1):43-8. doi: 10.1016/j.bandl.2009.02.004. Epub 2009 Apr 7.
In this work, we apply Granger causality analysis to high spatiotemporal resolution intracranial EEG (iEEG) data to examine how different components of the left perisylvian language network interact during spoken language perception. The specific focus is on the characterization of serial versus parallel processing dependencies in the dominant hemisphere dorsal and ventral speech processing streams. Analysis of iEEG data from a large, 64-electrode grid implanted over the left perisylvian region in a single right-handed patient showed a consistent pattern of direct posterior superior temporal gyrus influence over sites distributed over the entire ventral pathway for words, non-words, and phonetically ambiguous items that could be interpreted either as words or non-words. For the phonetically ambiguous items, this pattern was overlayed by additional dependencies involving the inferior frontal gyrus, which influenced activation measured at electrodes located in both ventral and dorsal stream speech structures. Implications of these results for understanding the functional architecture of spoken language processing and interpreting the role of the posterior superior temporal gyrus in speech perception are discussed.
在这项研究中，我们将格兰杰因果分析应用于高时空分辨率的颅内脑电图（iEEG）数据，以研究左外侧裂周语言网络的不同组成部分在口语感知过程中是如何相互作用的。具体关注点在于优势半球背侧和腹侧言语处理流中串行与并行处理依赖性的特征。对一名右利手患者左外侧裂周区域植入的大型64电极网格采集的iEEG数据进行分析，结果显示，后颞上回对分布于整个腹侧通路的部位存在一致的直接影响模式，这些部位涉及单词、非单词以及在语音上模棱两可、既可以解释为单词也可以解释为非单词的项目。对于语音上模棱两可的项目，这种模式被涉及额下回的额外依赖性所叠加，额下回影响了在腹侧和背侧流言语结构中电极处测得的激活。本文讨论了这些结果对于理解口语处理功能结构以及解释后颞上回在言语感知中作用的意义。
