INSERM 1028, CNRS UMR 5292, Brain Dynamics and Cognition Team, Lyon Neuroscience Research Center, University Claude Bernard Lyon 1, F-69500 Bron, France.
J Neurosci. 2012 May 9;32(19):6421-34. doi: 10.1523/JNEUROSCI.4363-11.2012.
Reading sentences involves a distributed network of brain regions acting in concert surrounding the left sylvian fissure. The mechanisms of neural communication underlying the extraction and integration of verbal information across subcomponents of this reading network are still largely unknown. We recorded intracranial EEG activity in 12 epileptic human patients performing natural sentence reading and analyzed long-range corticocortical interactions between local neural activations. During a simple task contrasting semantic, phonological, and purely visual processes, we found process-specific neural activity elicited at the single-trial level, characterized by energy increases in a broad gamma band (40-150 Hz). Correlation analysis between task-induced gamma-band activations revealed a selective fragmentation of the network into specialized subnetworks supporting sentence-level semantic analysis and phonological processing. We extend the implications of our results beyond reading, to propose that gamma-band amplitude correlations might constitute a fundamental mechanism for large-scale neural integration during high-level cognition.
阅读句子涉及到左大脑外侧裂周围协同作用的大脑区域的分布式网络。阅读网络子成分之间提取和整合言语信息的神经通讯机制在很大程度上仍然未知。我们在 12 名进行自然句子阅读的癫痫患者中记录了颅内 EEG 活动，并分析了长程皮质间相互作用。在一个简单的任务中对比语义、语音和纯粹的视觉过程中，我们发现了在单试水平上引起的特定于过程的神经活动，其特征是在一个广泛的伽马频带（40-150Hz）中能量增加。任务诱导的伽马带激活之间的相关分析揭示了网络的选择性碎片化，形成支持句子级语义分析和语音处理的专门子网。我们将我们结果的意义扩展到阅读之外，提出伽马带幅度相关可能是高级认知中大规模神经整合的基本机制。
