According to embodied theories, the symbols used by language are meaningful because they are grounded in perception, action, and emotion. In contrast, according to abstract symbol theories, meaning arises from the syntactic combination of abstract, amodal symbols. If language is grounded in internal bodily states, then one would predict that emotion affects language. Consistent with this, advocates of embodied theories propose a strong link between emotion and language [Havas, D., Glenberg, A. M., & Rinck, M. Emotion simulation during language comprehension. Psychonomic Bulletin & Review, 14, 436–441, 2007; Niedenthal, P. M. Embodying emotion. Science, 316, 1002–1005, 2007]. The goal of this study was to test abstract symbol vs. embodied views of language by investigating whether mood affects semantic processing. To this aim, we induced different emotional states (happy vs. sad) by presenting film clips that displayed fragments from a happy movie or a sad movie. The clips were presented before and during blocks of sentences in which the cloze probability of mid-sentence critical words varied (high vs. low). Participants read sentences while ERPs were recorded. The mood induction procedure was successful: Participants watching the happy film clips scored higher on a mood scale than those watching the sad clips. For N400, mood by cloze probability interactions were obtained. The N400 cloze effect was strongly reduced in the sad mood compared with the happy mood condition. Furthermore, a difference in late positivity was only present for the sad mood condition. The mood by semantic processing interaction observed for N400 supports embodied theories of meaning and challenges abstract symbol theories that assume that processing of word meaning reflects a modular process.

In the language domain, most studies of error monitoring have been devoted to language production. However, in language perception, errors are made as well and we are able to detect them. According to the monitoring theory of language perception, a strong conflict between what is expected and what is observed triggers reanalysis to check for possible perceptual errors, a process reflected by the P600. This is at variance with the dominant view that the P600 reflects syntactic reanalysis or repair, after syntactic violations or ambiguity. In the present study, the prediction of the monitoring theory of language perception was tested, that only a strong conflict between expectancies triggers reanalysis to check for possible perceptual errors, reflected by the P600. Therefore, we manipulated plausibility, and hypothesized that when a critical noun is mildly implausible in the given sentence (e.g., “The eye consisting of among other things a pupil, iris, and eyebrow …”), a mild conflict arises between the expected and unexpected event; integration difficulties arise due to the unexpectedness but they are resolved successfully, thereby eliciting an N400 effect. When the noun is deeply implausible however (e.g., “The eye consisting of among other things a pupil, iris, and sticker …”), a strong conflict arises; integration fails and reanalysis is triggered, eliciting a P600 effect. Our hypothesis was confirmed; only when the conflict between the expected and unexpected event is strong enough, reanalysis is triggered.