Variability in native and nonnative language: An ERP study of semantic and grammar processing

Abstract This study examined individual-level variability in N400 and P600 ERP correlates of native and nonnative language sentence processing of semantic and grammar information. Twenty-six native English-speaking learners of Spanish as a second language were tested. Participants completed sentence reading tasks in English and Spanish during EEG recording. The group-level results for grammar showed P600s in the native and nonnative language. For semantics, there was an N400 only in the native language. Individual-level ERP patterns revealed that, for native language semantics, about two thirds of participants showed N400s, but approximately one-third showed P600s. For native language grammar, approximately one third of participants exhibited N400s instead of P600s. Individual-level ERPs showed similar variability in the nonnative language for semantics and grammar, and N400/P600 variability in Spanish related to Spanish verbal fluency and grammar knowledge. This contributes knowledge of how nonnative and native language neurocognition compare regarding the processing routes that individuals use during comprehension.