Electrophysiological insights into the role of proficiency in bilingual novel and conventional metaphor processing

While novel and conventional metaphor comprehension has received much attention in the monolingual context, thus far little electrophysiological research has been conducted with a view to examining how bilingual speakers process metaphors in their non-native language (L2) as well as how L2 proficiency level might modulate such processes. The present study aims to investigate the electrophysiological correlates of novel and conventional metaphor comprehension in intermediate and advanced Chinese-English bilingual speakers. The participants performed a semantic decision task to English (L2) novel metaphoric, conventional metaphoric, literal, and anomalous word pairs. The results showed a graded N400 effect from literal utterances, to conventional metaphors, novel metaphors, and finally to anomalous utterances in both groups of participants, indicating that both types of metaphors were more cognitively taxing than literal utterances, irrespectively of L2 proficiency level. Additionally, between-group differences that were irrespective of utterance type were found in the N400 time frame, indicating more extended lexico-semantic access in the intermediate relative to the advanced group. Finally, in both groups of participants, an anterior sustained negativity was found in response to anomalous, novel metaphoric, and conventional metaphoric word pairs, thus suggesting a continuing difficulty of meaning integration.