Department of Neuropsychology, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany; Department of Psychology, University of Regensburg, Regensburg, Germany.
Department of Neuropsychology, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany.
Cortex. 2019 Jun;115:86-98. doi: 10.1016/j.cortex.2019.01.010. Epub 2019 Jan 28.
Sentence comprehension requires the rapid analysis of semantic and syntactic information. These processes are supported by a left hemispheric dominant fronto-temporal network, including left posterior inferior frontal gyrus (pIFG) and posterior superior temporal gyrus/sulcus (pSTG/STS). Previous electroencephalography (EEG) studies have associated semantic expectancy within a sentence with a modulation of the N400 and syntactic gender violations with increases in the LAN and P600. Here, we combined focal perturbations of neural activity by means of short bursts of transcranial magnetic stimulation (TMS) with simultaneous EEG recordings to probe the functional relevance of pIFG and pSTG/STS for sentence comprehension. We applied 10 Hz TMS bursts of three pulses at verb onset during auditory presentation of short sentences. Verb-based semantic expectancy and article-based syntactic gender requirement were manipulated for the sentence final noun. We did not find any TMS effect at the noun. However, TMS had a short-lasting impact at the mid-sentence verb that differed for the two stimulation sites. Specifically, TMS over pIFG elicited a frontal positivity in the first 200 msec post verb onset whereas TMS over pSTG/STS was limited to a parietal negativity at 200-400 msec post verb onset. This indicates that during verb processing in sentential context, frontal brain areas play an earlier role than temporal areas in predicting the upcoming noun. The short-living perturbation effects at the mid-sentence verb suggest a high degree of online compensation within the language system since the sentence final noun processing was unaffected.
句子理解需要快速分析语义和句法信息。这些过程由一个左半球优势额颞网络支持，包括左侧后下额回（pIFG）和后上颞叶/回（pSTG/STS）。先前的脑电图（EEG）研究表明，句子内的语义预期与 N400 的调制有关，而句法性别违反与 LAN 和 P600 的增加有关。在这里，我们通过短串经颅磁刺激（TMS）结合同时的 EEG 记录来结合神经活动的焦点干扰，以探究 pIFG 和 pSTG/STS 对句子理解的功能相关性。我们在短句子的听觉呈现期间在动词开始时应用三个脉冲的 10 Hz TMS 脉冲串。基于动词的语义预期和基于冠词的句法性别要求被操纵为句子结尾的名词。我们在名词上没有发现任何 TMS 效应。然而，TMS 在中频句子动词上有短暂的影响，两个刺激部位的影响不同。具体来说，pIFG 上的 TMS 在动词开始后 200 毫秒内引发了额部正性，而 pSTG/STS 上的 TMS 仅限于动词开始后 200-400 毫秒的顶负性。这表明在句子语境中处理动词时，额叶脑区比颞叶脑区更早地发挥作用，以预测即将到来的名词。中频句子动词的短暂干扰效应表明语言系统具有高度的在线补偿能力，因为句子结尾名词的处理不受影响。
