Expanding on work comparing effects in word pairs and sentences, researchers began to look at the comprehension of multi-sentence texts (reviewed in Van Berkum 2009). They found that N400 amplitudes were sensitive to discourse in the same manner and with the same timecourse as to word- and (isolated) sentence-level constraints, and that the pattern of prevalence of higher over lower levels of analysis extended to discourse (e.g., discourse constraints reversing N400 repetition effects: Camblin et al 2007). For example, simply adding an informative title to a locally coherent but globally opaque text passage sufficed to reduce the amplitude of the average N400 to all the content words in the passage. Further work showed that N400s to words in identical, comprehensible sentences were smaller when they were consistent with the discourse context than when they were not. Thus, discourse effects unfold very rapidly – in the case of a spoken word, even before its acoustic realization ends. Given the similarity of these N400 discourse effects to other linguistic and even non-linguistic N400 effects, it would seem unnecessary to resort to any language-specific model to account for them.
