Effects of context in human sentence parsing: Evidence against a discourse-based proposal mechanism.

Two subject-Paced reading experiments were carried out to examine the way in which discourse information exerts its influence in sentence comprehension. The results show that whereas prior discourse context appears to affect the way in which sentences are ultimately parsed, there is no evidence that it has any direct influence on the initial assignment of structure. These findings argue against parsing models (such as the referential support model) that assume that discourse factors influence the initial structural assignment. In contrast, they support models (e.g., the "garden path" model) that posit that initial structural proposals are made on a purely syntactic basis, whereas discourse effects are confined to a later set of disposal operations. These conclusions are discussed in the light of broader accounts of interactive processing.