The functional analysis of the N400 component: lexical access, integration or can we have it both ways?

Abstract

In this study, we provide a functional analysis of the N400 component. This is a much replicated neurophysiological response which occurs 400ms after the onset of stimuli. This response is said to reflect the degree to which preceding context (sentences or priming words) predicts an upcoming word, and thus affects its processing. Competing hypotheses claim that cognitive operations underlying N400 effects are either lexical access or integration of the word in the preceding context. Lau et al. (2006) compared N400 effects in priming pairs and sentential contexts, and found quantitative differences, but no qualitative differences. This led them to conclude that lexical access is the underlying operation reflected in N400 effects in both cases. We challenge that conclusion by showing that structure mediates relations between words, even when not in a sentential content.

Keywords

• n400, priming, sentence processing, erp.