Conceptions of Limited Attention and Discourse Focus

Walker (1996) presents a cache model of the operation of attention in the processing of discourse as an alternative to the focus space stack that was proposed previously by Grosz and Sidner (Grosz 1977a; Grosz and Sidner 1986). In this squib, we present a critical analysis of the cache model and of Walker's supporting evidence from anaphora in discourses with interruptions and from informationally redundant utterances. We argue that the cache model is underdetermined in several ways that are crucial to a comparison of the two models and conclude that Walker has not established the superiority of the cache model. We also argue that psycholinguistic evidence does not support the cache model over the focus stack model.