Memory for narrative and expository text: independent influences of semantic associations and text organization.

The author examined memory for text in terms of the independent influences of semantic knowledge associations and text organization. Semantic associations were operationalized as the semantic relatedness between individual text concepts and the text as a whole and assessed with latent semantic analysis. The author assessed text organization by simulating comprehension with the construction integration model. Text organization consistently accounted for unique variance in recall. Semantic associations strongly predicted expository recall and predicted narrative recall significantly but to a lesser extent, even when the familiarity of the narrative content was manipulated. Results suggest that prior semantic associations and novel associations in the text structure influence memory independently, and that these influences can be affected by text genre. When comprehending and recalling a text, readers rely on both the text itself and prior knowledge in a variety of ways. To gain a complete understanding of text comprehension and memory, researchers need to understand how these influences relate to one another. One aspect of prior knowledge that is important is the aspect of associations in semantic memory. Models of text processing indicate that semantic associations are important for activating relevant information that the reader may use to aid in comprehension (Kintsch, 1998; Myers & O’Brien, 1998). Semantic associations are likely to be important in predicting text memory as well. Another important factor in determining text memory is the organization of concepts in the text itself. Prior research has indicated that during comprehension, readers form a mental representation of text information in which the constituent elements (concepts) of the sentences are parsed into propositions, which indicate how the elements are related in the sentences. These propositions are then connected together across sentences to form a textbase representation (van Dijk & Kintsch, 1983). The textbase is a mental representation of a text that reflects the organization of the text elements as dictated by the text structure. In this article, semantic associations and text organization are evaluated in terms of their independent influence on memory for text. Recall of text information is predicted by computational models that assess semantic associations (Landauer & Dumais, 1997) and textbase strength (Kintsch, 1998). In addition, I examine these two influences on memory for both narrative and expository texts in order to assess the extent to which their relative influence may change under different processing circumstances. To make concrete the factors of semantic associations and text organization, consider a text describing basic information about the human circulatory system that contains the following sentence: Blood leaves the heart through a big tube called the aorta, which is an inch thick. This sentence contains several text elements (concepts): LEAVES, BLOOD, HEART, TUBE, BIG, AORTA, INCH-THICK. Different theories of text processing provide means by which the relative strength of these elements in memory can be predicted. An analysis of the propositional structure of the sentence, for example, reveals the following complex proposition (van Dijk & Kintsch, 1983):