Perceived language competence modulates criteria for speech error processing: evidence from event-related potentials

With event-related potentials we examined how speaker identity affects the processing of speech errors. In two experiments with probe verification and sentence correctness judgement tasks, respectively, grammatical agreement violations and slips of the tongue were embedded in German sentences spoken in native or Chinese accent. Portraits of European or Asian persons served as cues for speaker's identity. In Experiment 1, only a P600 was elicited by grammatical agreement errors in native speech in the second presentations. In Experiment 2, grammatical errors again elicited a P600 only in native speech. Slips of the tongue, however, elicited a P600 in both native and non-native speech and a N400 for native speech. Hence, perceived speaker nativeness seems to modulate the integration of grammatical agreement violations into the utterance. Slips of the tongue induced (re)interpretation processes (P600) for both native and non-native speech, whereas retrieval of lexico-semantic information (N400) is reduced in non-native speech.

本研究借助事件相关电位（event-related potentials）技术，探究了说话者身份对言语错误加工过程的影响。本研究设置两项实验，分别采用探测验证任务与句子正确性判断范式，实验材料为带有德语母语口音或汉语口音的德语语句，其中分别嵌入了语法一致性违例与口误两类言语错误，并以欧洲或亚洲人物肖像作为说话者身份的提示线索。实验1中，仅母语口音语句中的语法一致性违例在第二次呈现时，方可诱发出P600脑电成分。实验2中，语法错误仍仅在母语口音语句中诱发出P600脑电成分。但口误在母语与非母语口音语句中均能诱发出P600脑电成分，且在母语口音语句中还会额外诱发出N400脑电成分。由此可知，个体感知到的说话者母语熟练度，可调节语法一致性违例在语句中的整合过程。口误可在母语与非母语口音语句中引发（重新）解读过程（对应P600脑电成分）；而在非母语口音语句中，词汇语义信息的提取过程（对应N400脑电成分）则会受到削弱。