The format of metaphorical meaning: Neurophysiological evidence for dynamic and flexible image-based representations

Theories of metaphor comprehension have long debated the representational format of metaphorical meaning. While classical accounts describe metaphors as abstract propositional representations, other theories have, to varying degrees, argued that metaphor evokes mental imagery. Yet neurophysiological evidence that speakers construct mental images reflecting the complete figurative interpretation remains scarce. Here, we investigated whether metaphors give rise to mental images resembling those generated during imagery or whether they rely predominantly on propositional representations. We designed a novel picture-matching paradigm in which identical target pictures were preceded by either matching or mismatching stimuli across four tasks: another picture (Physical task), an adjective prompting imagery (Imagery task), a literal sentence (Literal task), or a metaphorical sentence (Metaphorical task). Across multiple levels of analysis of the EEG signal, the Metaphorical task patterned more closely with imagery than with literal language. Metaphors elicited enhanced P300 and attenuated N200 responses, greater recruitment of occipito-temporal visual regions, and stronger upper-alpha/lower-beta desynchronization than literal descriptions, indicating that participants constructed perceptually richer representations. These effects were further modulated by individual differences in imagery and vocabulary. However, at later stages, metaphors also diverged from imagery, which showed more pronounced brain signatures associated with memory retrieval and representational maintenance. These findings indicate that metaphorical meanings yield image-based representations while remaining constrained by propositional content. Collectively, the results confirm that metaphor “sets things before the eyes”, but it does so through the dynamic and flexible interaction of perceptual simulation with propositional information, in line with multiple representation theories of conceptual knowledge.