An ERP analysis of iconic language and iconic thinking. The case of metaphor

Objective: The present study intends to compare the comprehension of iconic language and the visualization strategy by and ERP analysis applied to metaphor. Several studies investigated metaphor from semantic, cognitive and communicative points of view, but only few were interested in explaining the representational form of figurative language. Participants and Methods: 320 sentences (equally shared in literal and familiar metaphorical endings), were presented to 36 subjects, grouped into three different categories: low-, medium and high-visualizers. An ERPs analysis was applied to the comprehension process, taking into account the temporal window of 250-350 ms post-stimulus. Results: ERP analysis showed a negative peak around 340 msec (N3) for both the literal and metaphorical endings, with an increased amplitude for the last one. The methaphorical endings revealed the presence of an higher negative deflection in comparison with the literal endings. Moreover, high-visualizers showed an ampler N3 than the medium- and low- ones for the metaphorical endings. Finally, the occipital area were more activated than the others as a function of the metaphorical sentences and the visualization strategy. Conclusions: These results suggest that metaphor involves an iconic representation, more posteriorly distribuited on the brain, than the literal condition. Moreover, visualizers may increase the iconic way of representation, by using images to comprehend the metaphorical meaning of a sentence.