Ambiguous words in sentences: brain indices for native and non-native disambiguation.

In the present study, we compare how native speakers and second language learners process homonyms (such as bank and jam) in sentence context during a late processing phase that involves selection of the appropriate meaning. With both participant groups, we conducted a combined reaction time (RT)/event-related brain potential (ERP) lexical decision experiment with a long stimulus-onset asynchrony (SOA) of 800 ms. Related primes were homonyms at the end of sentences with a context biasing one of the homonym meanings, and targets reflected the contextually appropriate or inappropriate meaning. Both RT and ERP semantic priming in the N400 component revealed that for both natives and learners, only contextually appropriate meanings were primed, or still active, late in processing. The results indicate that L2 learners show similar, though slower, homonym processing mechanisms to those of native speakers of a language, and that both groups can achieve disambiguation based on semantic context.