The Role of Syntactic and Semantic Cues in Preventing Temporary Illusions of Plausibility

Unexpected words within a context elicit large N400 brain potentials. However, sometimes the N400 at an unexpected word is small when stereotypical agent and patient roles are reversed, such as at "arrested" in "the cop that the thief arrested." In a study of 74 native German speakers, we demonstrate evidence that readers can avoid this so-called N400 semantic illusion if the verb is delayed with neutral information such as "that evening," but are less able to do so if the delay contains cues that could further strengthen the canonical interpretation, such as "with handcuffs." In doing so, we provide a conceptual replication of a relatively new finding and extend previous research by showing that the semantic content of the delay is important. Moreover, we demonstrate evidence that the effect of only the neutral delay increases as the experiment progresses. We propose an interpretation of these findings with reference to the Sentence Gestalt model [Rabovsky, M., Hansen, S. S., & McClelland, J. L. Modelling the N400 brain potential as change in a probabilistic representation of meaning. Nature Human Behaviour, 2, 693, 2018], which accounts for the initial illusion as resulting from uncertainty and an erroneous interpretation based on a strong semantic attractor. Two additional, novel contributions of the work are a demonstration that the illusion can be elicited in German, despite its explicit subject-object case marking, and an exploration of illusion effect among individual readers.