Rommers, J. 1 , Bastiaansen, M. C. 1, 2 & Dijkstra, T. 1, 2
1 Max Planck Institute for Psycholinguistics, Nijmegen.
2 Radboud University, Donders Centre for Brain, Cognition and Behaviour, Nijmegen.
Evidence from literal sentence comprehension suggests that sufficiently constraining sentence contexts can lead to semantically specified expectations for upcoming words. In an EEG experiment, we investigated whether this semantic expectancy extends to the case of predictable words in opaque idiomatic expressions, in which the literal word meanings are unrelated to the figurative meaning of the expression as a whole (e.g., Dutch "walk against the lamp", meaning "to get caught"). Dutch participants were presented with two types of predictable sentence contexts: literal (e.g., transl. "After lunch the electrician screwed the light bulb into the...") and idiomatic (e.g., transl. "After many transactions the fraud eventually walked against the..."). In both contexts the critical word was (1) a correct and expected word (e.g., "lamp"), (2) a word that was semantically related to the expected word (e.g., "candle"), or (3) a semantically unrelated word (e.g., "fish"). Both (2) and (3) were semantic violations. In literal contexts previous findings were replicated: a graded N400 was observed, being largest for the semantically unrelated words, intermediate for semantically related words, and smallest for correct words. In contrast, in idiomatic contexts the N400s to semantically related and unrelated words were indistinguishable. These results suggest that idiomatic contexts do not lead to activation of the semantics of the predictable words. Furthermore, in idiomatic contexts only, the violations elicited a late positivity which was independent of semantic relatedness, suggesting that the semantic violations were treated as form violations instead. The results highlight the context-dependency of semantic processing and have consequences for theories of idiom comprehension.