查看文章

Coherence is a key construct by which discourse is defined. Understanding coherence represents a common goal of various discourse analyses (van Dijk, 1977). A discourse is said to be coherent when it hangs together as a unit or makes sense as a whole. A discourse may be coherently produced despite difficulties at lexical or syntactic levels. However, this is not always the case. For this reason, investigation of discourse coherence represents a promising approach to the analysis of aphasic discourse. Such analysis allows for examination of the relationship between sentence-level and discourse-level phenomena (Ulatowska & Olness, 1997). The aspects of coherence investigated in this study are related inherently to the classic notions of narrative evaluation and narrative event line (Labov, 1972; Labov & Waletzky, 1967). These constructs have had widespread influence on the study of narrative across disciplines (Bamberg, 1997) and are relevant to the two aspects of coherence studied here. The first is thematic coherence, which is derived from the topic of a narrative. This coherence can be expressed as narrative evaluation. The second is temporal/causal coherence, which is built through the relations between actions on the narrative event line and is carried primarily by the verb.