Abstract Evidence shows that second language (L2) processing depends on the Age of Acquisition (AoA), proficiency and differences between L1 and L2 grammar. Here we focus on the influence of the latter factor on L2 processing. To this end, we tested early (AoA = 3 years) and highly proficient Spanish-Basque and Basque-Spanish bilinguals by means of Event-Related Potentials (ERPs) while processing noun morphology in Basque (Experiments 1 and 2) and Spanish (Experiments 3 and 4). Both behavioral and electrophysiological results revealed significant differences between L1 and L2 speakers: non-natives made more errors and elicited a smaller P600 for violations than natives when processing ergative and allative morphology in Basque and accusative, dative and allative in Spanish. These findings reveal that, even for early and highly proficient bilinguals, (a) L2 processing is modulated by L1 grammar and (b) native vs. non-native differences obtain only when L1 and L2 morphological categories differ but not otherwise.

中文翻译：

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双语者处理名词形态：来自事件相关电位的语言距离假设的证据

摘要 证据表明，第二语言 (L2) 的处理取决于习得年龄 (AoA)、熟练程度以及 L1 和 L2 语法之间的差异。这里我们重点讨论后一个因素对 L2 处理的影响。为此，我们在处理巴斯克语（实验 1 和 2）和西班牙语（实验 1 和 2）的名词形态时，通过事件相关电位（ERP）测试了早期（AoA = 3 年）和高度熟练的西班牙语-巴斯克语和巴斯克语-西班牙语双语者3 和 4）。行为和电生理结果都揭示了 L1 和 L2 说话者之间的显着差异：在处理巴斯克语的作格和变格形态以及西班牙语的宾格、与格和变格形态时，非母语者比母语者犯了更多的错误并引发了更小的 P600 违规行为。这些发现表明，