First time ’ s the charm : First - mention lengthening as an automated act

Words are longer when they are mentioned for the first time within a discourse and shorter in subsequent mentions. This Repetition Effect is usually attributed to the fact that, with repetition, the word becomes more accessible to either the speaker or the listener. In the present paper, we argue that the Repetition Effect is better seen as lengthening of words that are mentioned for the first time within a discourse (Bell et al., 2009). Furthermore, we propose that this firstmention lengthening is an automatic behavior triggered by discourse structure, rather than reflecting online changes in word accessibility for either interlocutor. In support of this proposal, we show that words are always longer when they are mentioned for the first time within a coherent stretch of discourse, even when they have previously been mentioned by the speaker to the same listener and are therefore highly accessible to both interlocutors.