Ten years ago, researchers using event-related brain potentials to study language comprehension were puzzled by what looked like a Semantic Illusion: Semantically anomalous, but structurally well-formed sentences did not affect the N400 component—traditionally taken to reflect semantic integration—but instead produced a P600 effect, which is generally linked to syntactic processing. This finding led to a considerable amount of debate, and a number of complex processing models have been proposed as an explanation. What these models have in common is that they (...) postulate two or more separate processing streams, in order to reconcile the Semantic Illusion and other semantically induced P600 effects with the traditional interpretations of the N400 and the P600. Recently, however, these multi-stream models have been called into question, and a simpler single-stream model has been proposed. According to this alternative model, the N400 component reflects the retrieval of word meaning from semantic memory, and the P600 component indexes the integration of this meaning into the unfolding utterance interpretation. In the present paper, we provide support for this “Retrieval–Integration ” account by instantiating it as a neurocomputational model. This neurocomputational model is the first to successfully simulate the N400 and P600 amplitude in language comprehension, and simulations with this model provide a proof of concept of the single-stream RI account of semantically induced patterns of N400 and P600 modulations. (shrink)

The aim of this article is to investigate whether choosing the appropriate referring expression requires taking into account the hearer’s perspective, as is predicted under some versions of bidirectional Optimality Theory but is unexpected under other versions. We did this by comparing the results of 25 young and 25 elderly adults on an elicitation task based on eight different picture stories, and a comprehension task based on eight similar written stories. With respect to the elicitation task, we found that elderly (...) adults produce pronouns significantly more often than young adults when referring to the old topic in the presence of a new topic. With respect to the comprehension task, no significant differences were found between elderly and young adults. These results support the hypothesis that speakers optimize bidirectionally and take into account hearers when selecting a referring expression. If the use of a pronoun will lead to an unintended interpretation by the hearer, the speaker will use an unambiguous definite noun phrase instead. Because elderly adults are more limited in their processing capacities, as is indicated by their smaller working memory capacity, as speakers they will not always be able to reason about the hearer’s choices. As a result, they frequently produce non-recoverable pronouns. (shrink)