The role of executive control ability in second language metaphor comprehension: Evidence from ERPs and sLORETA

Previous research suggests that executive control ability may contribute to second language (L2) metaphor comprehension, and this relationship may be modulated by metaphor familiarity. However, so far most studies have been done with behavioral experiments. Using the event-related potential (ERP) and standardized low-resolution brain electromagnetic tomography analysis (sLORETA), this study adopted the semantic priming paradigm to examine the role of executive control ability in L2 metaphor comprehension with different degrees of familiarity. The Stroop task was used to measure executive control ability and differentiate the two groups of participants who were presented with three types of word-pair expressions: familiar metaphoric expressions, unfamiliar metaphoric expressions and literal expressions. They were then asked to perform a semantic judgment task. Results revealed more negative amplitudes of N400 and P600 components in participants of low executive control compared with those of high executive control. Metaphor familiarity modulated N400 of both groups of high and low executive control, whereas it only affected P600 of participants of low executive control. sLORETA analysis of both N400 and P600 revealed stronger activation for the low versus high executive control group in the right superior frontal gyrus and middle frontal gyrus during low familiar metaphor comprehension. These results suggest that executive control plays a role in L2 metaphor comprehension, while it is modulated by metaphor familiarity.