Data_Sheet_1_ERP Evidences of Rapid Semantic Learning in Foreign Language Word Comprehension.pdf

The event-related potential (ERP) of electroencephalography (EEG) signals has been well studied in the case of native language speech comprehension using semantically matched and mis-matched end-words. The presence of semantic incongruity in the audio stimulus elicits a N400 component in the ERP waveform. However, it is unclear whether the semantic dissimilarity effects in ERP also appear for foreign language words that were learned in a rapid language learning task. In this study, we introduced the semantics of Japanese words to subjects who had no prior exposure to Japanese language. Following this language learning task, we performed ERP analysis using English sentences of semantically matched and mis-matched nature where the end-words were replaced with their Japanese counterparts. The ERP analysis revealed that, even with a short learning cycle, the semantically matched and mis-matched end-words elicited different EEG patterns (similar to the native language case). However, the patterns seen for the newly learnt word stimuli showed the presence of P600 component (delayed and opposite in polarity to those seen in the known language). A topographical analysis revealed that P600 responses were pre-dominantly observed in the parietal region and in the left hemisphere. The absence of N400 component in this rapid learning task can be considered as evidence for its association with long-term memory processing. Further, the ERP waveform for the Japanese end-words, prior to semantic learning, showed a P3a component owing to the subject's reaction to a novel stimulus. These differences were more pronounced in the centro-parietal scalp electrodes.

脑电图（electroencephalography, EEG）信号的事件相关电位（event-related potential, ERP）在采用语义匹配与不匹配尾词的母语语音理解研究中已得到充分探究。当听觉刺激存在语义不协调时，会在ERP波形中诱发出N400成分（N400 component）。然而，目前尚不清楚ERP中的语义差异效应是否也会出现在通过快速语言学习任务习得的外语词汇中。本研究向无日语学习经历的受试者教授日语词汇的语义知识，完成该语言学习任务后，我们采用语义匹配与不匹配的英语句子开展ERP分析，将句尾词替换为对应的日语词汇。ERP分析结果表明，即便仅经过短暂学习周期，语义匹配与不匹配的尾词仍能诱发出不同的脑电图模式，这与母语场景下的结果类似。但针对新习得词汇刺激的脑电模式显示存在P600成分（P600 component），其极性与已知语言中观察到的P600相反且出现延迟。脑电地形分析显示，P600反应主要出现在顶叶区域与左半球。本次快速学习任务中未检测到N400成分，这可作为其与长期记忆加工相关的佐证。此外，在语义学习前，针对日语尾词的ERP波形显示存在P3a成分（P3a component），该成分源于受试者对新异刺激的响应，此类差异在中央顶区头皮电极上表现更为显著。