Effects of mobilizing prior knowledge on information processing were studied with 3 groups of 12 adult subjects each. The assumption that activating different kinds of prior knowledge would induce different information processing activities during subsequent text processing (inferencing or elaborating) was tested using passages about fishing policy or tourism in the European Economic Community. It was hypothesized that inferences are induced by activating prior knowledge that could have evolved into a schema through experiences in a particular domain, and that they instantiate the schema. Elaborations, on the other hand, would result from activating limited prior knowledge, represented in an associative network. Elaborations would be required during subsequent text processing to bridge gaps between conceptual nodes in the text and nodes in the associative network. Findings suggested that inferences were mostly drawn when the activated prior knowledge had evolved into a schema, but elaborations were most frequent when limited prior knowledge was activated, represented in an associative net. Appendixes contain a sample passage, and an analysis of responses to the passage. (Contains 2 tables and 17 references.) (Author/SLD)