The integration between the word and gesture meaning systems: evidence from RTs and ERPs.

Aim of the present study was to assess the relationships between the gesture and language meaning systems with a priming paradigm at both the behavioral and the neurophysiological levels. Fifteen participants watched forty video-clips of different types of iconic gestures followed by words (nouns or verbs), which could be related or unrelated in meaning. Behavioral results showed an interference effect between the meaning of iconic gestures and that of unrelated words. ERPs analyses showed a greater P200 component for nouns than for verbs, which was modulated by the relation with the preceding gesture, and a clear N400 with greater negative values for verbs than for nouns. Although there was evidence for a deep integration between word and gesture in the P200 time window; the lack of interaction between the meaning relation and the grammatical class in the N400 time window suggests that the meaning systems of word and gesture diffe