Irony is more cognitively taxing than literalness in the second language and more effective in the first: Evidence from event-related potentials.

Irony tends to be processed with greater cognitive effort than literalness. It remains unclear, however, whether bilinguals process irony differently in the native (L1) and second (L2) language. Here, we investigated the neurophysiological correlates of irony comprehension in highly proficient late Polish-English bilinguals reading praise and criticism that were either literal or ironic in both languages. We found an interaction between ironicity and language on the N400, an index of semantic integration effort and processing depth, with ironic statements eliciting greater amplitudes than literal statements in L2, when no such difference was observed in L1. At the stage of semantic reevaluation, indexed by the late positive potential (LPP), amplitudes increased for ironic as compared to literal statements in L1, but not in L2. A follow-up peak-to-peak analysis using the N400 as baseline, however, pointed to comparable reevaluation processes across languages, suggesting that the LPP modulation may partly reflect earlier differences in semantic processing rather than differential reevaluation per se. We interpret the N400 modulation in L2 as an indication that ironic statements are more cognitively taxing than literal statements in L2. The LPP modulation tentatively suggests that irony prompts more reevaluation in L1 than L2, though this interpretation warrants caution in light of the peak-to-peak findings. Our findings provide novel evidence that bilinguals exert greater cognitive effort when processing irony in their second language and that ironic meaning may resonate more strongly in the native language.