The use of referential expressions in structuring discourse

Referential expressions that refer to entities that occur in a text differ in lexical specificity. It is claimed that if these anaphoric expressions are more specific than necessary for their identificational function, they not only relate the current information to the intended referent, but also contribute to the expression of the thematic structure of the discourse and to the comprehension of the thematic structure. In two controlled production experiments, it is demonstrated that thematic shifts are produced when one has to make use of such an overspecified expression, and that overspecified referential expressions are produced when one has to formulate a thematic shift. In two comprehension experiments, using a probe recognition technique, it is shown that an overspecified referential expression decreases the availability of information contained in a sentence that precedes the overspecification. This finding is interpreted in terms of the thematic structuring function of referential expressions in the understanding of discourse