• EEG
• ERP
• memory
• metaphor
• multimodality
• neurolinguistics
• neuroscience

Within the field of neurolinguistics and cognitive neuroscience of language, the study of metaphor through electrophysiological techniques plays a special role, as understanding how such a quintessential figure of speech is processed gives precious insight on the elaboration of inferential processes by the brain. Electrophysiological studies of metaphor have underlined two crucial components of the Event-Related Potentials: the N400 component, a centro-parietal negative deflection at 250-500ms that reflect semantic comprehension and context integration; the P600 component, a positive peak in activity at around 600ms that indexes syntactic framing and sentence revision. While cognitive linguistics accounts have explored the nature of the visual metaphor as a favorable mode of communication, studies in neurolinguistics have never thoroughly investigated the role of multimodality in metaphors. With the development of social communication and advertising, the use of metaphoric pictures has gained more and more interest, as the neuroscientific community still does not know to what extent this use facilitates communication or increases its effectiveness. Therefore, there is the need of a new study that incorporates a tight set of stimuli in a rigorous experimental paradigm. We designed a set of stimuli comprising metaphorical and literal noun pairs in either monomodal (verbal) or multimodal (verbo-pictorial) conditions. A cued memory recall on-line task followed each experimental block to verify the effects on memory of all conditions. ERPs were computed and compared through cluster mass permutation tests. Preliminary results show that, compared to verbal metaphors, verbo-pictorial metaphors elicited an N400 effect that was sustained in time and more broadly distributed. This supports the idea that multimodal metaphors recruit a non-overlapping set of neural sources compared to verbal ones, and they may engage the cognitive system longer. Word-picture pairs were remembered better than word-word pairs, but this advantage was slightly larger for literal than metaphorical pairs, suggesting that the benefits possibly associated with multi-modal metaphors did here not particularly concern memory.