N400 ERPs for actions: building meaning in context

TLDR

Neuroscience links language and sensorimotor cognition, showing that during action comprehension the brain recruits semantic operations similar to those used for language and that the N400 component, traditionally tied to linguistic semantics, is also elicited by action-related material. This review surveys recent N400 studies on action comprehension and proposes a testable contextual fronto‑temporo‑parietal model to explain how the brain constructs meaning from action events. The authors examine action comprehension across everyday actions, co‑speech gestures, and motor planning semantics, and propose a contextual fronto‑temporo‑parietal model of meaning construction. The reviewed evidence indicates that both the N400 and action‑N400 reflect a shared neurocognitive mechanism that builds meaning through expectations derived from prior experience and current context.

Abstract

Converging neuroscientific evidence suggests the existence of close links between language and sensorimotor cognition. Accordingly, during the comprehension of meaningful actions, our brain would recruit semantic-related operations similar to those associated with the processing of language information. Consistent with this view, electrophysiological findings show that the N400 component, traditionally linked to the semantic processing of linguistic material, can also be elicited by action-related material. This review outlines recent data from N400 studies that examine the understanding of action events. We focus on three specific domains, including everyday action comprehension, co-speech gesture integration, and the semantics involved in motor planning and execution. Based on the reviewed findings, we suggest that both negativities (the N400 and the action-N400) reflect a common neurocognitive mechanism involved in the construction of meaning through the expectancies created by previous experiences and current contextual information. To shed light on how this process is instantiated in the brain, a testable contextual fronto-temporo-parietal model is proposed.