摘要目的 通过事件相关电位(ERP)的时空模式评估汉语句子理解中的神经机制. 方法 自2011年至2012年应用多通道ERP技术,采用汉语句子为刺激材料,观察15名受试者在阅读判断汉语句子结尾词语义匹配及结尾词语义不匹配时诱发的ERP的变化过程,记录刺激后100～580 ms时段的19通道ERP总平均图;同时利用上述语义匹配和语义不匹配的ERP数据,采用配对t检验形成t值的统计参数映像[SPM(t)]呈现地形图,对其时空模式进行分析. 结果 在结尾词语义匹配和不匹配两种条件下,19通道ER总平均图均可见N200、N400和P600成分:N200分布在双侧枕区及颞后区,N400、P600广泛分布于双顶中央枕区颞区;SPM(t)显示出3个阶段中多脑区域的差异:(1)在100～300 ms阶段,240ms时早期左颞枕-左额中区呈现显著正向效应;(2)在300～400 ms阶段N400成分,右颞后区、双中央顶区、左侧额叶的活动呈现负向效应;(3)在440～580ms阶段P600成分,双侧枕-顶-右颞广泛的活动呈现显著的正向效应. 结论 左颞枕-左额中区分布的正向效应反映了视觉词形的处理过程和初始句法过程;右颞后区、双中央顶区、左侧额叶分布的负向效应反映了语义的综合加工过程;双侧顶-枕-右颞分布的正向效应反映了整个句子理解意义上词语和句法的再整合分析.

abstractsObjective To elucidate the neuromechanism of Chinese words comprehension with spatiotemporal pattern of event-related potential (ERP).Methods Fifteen people were recruited during 2011 and 2012.After using Chinese words as stimulating materials,each subject was required to judge whether a target Chinese word belongs to the same class as semantic match or mismatch.EEG was recorded using an ERP system of 19 channels developed.Statistical parametric mapping of t-valus [SPM (t)] was gained from interpolation calculated by each channel's t-value.Results Under two classes,the ERP of 19 channels showed N200,N400 and P600 elements:N200 might be distributed in the bilateral occipital and post-temporal areas,and N400 and P600 might be widely distributed in the double top central-occipital and temporal region.SPM(t) presented differences in multiple regions in 3 stages:during 100-300 ms,the early left hemispheric significant positive deflections 240 ms in left temporoccipital and left frontal regions; during 300-400 ms (the N400 stage),negative deflections in right post-temporal,and both centroparietal and left frontal regions; during 440-580 ms (P600 stage),significant positive deflections in both occipitaloparietal and right temporal regions.Conclusion The positive effects within left temporoccipital and left frontal regions seem to reflect visual word processing and initial syntactic processing; the N400 effects within right post-temporal,both centroparietal and left frontal regions seem to reflect integrate semantic analysis processing,and P600 effects within occipitaloparietal and right temporal regions seem to reflect reanalysis and the integration of semantic and syntactic to obtain the overall meanings of Chinese sentences