Prior knowledge and memory: the episodic encoding of implicitly activated associates and rhymes.

The presentation of a familiar word activates related concepts, and, once encoded, related concepts interfere with memory for the work actually presented. Presented words that activate larger numbers of related concepts are generally more difficult to recall than those that activate smaller numbers. The purpose of the present experiments was to explore the effects of study-trial orientation and test delay on the encoding of both rhyme- and meaning-related concepts. The results of Experiments 1 and 2 indicate that meaning-related concepts are encoded and interfere with memory for the presented target regardless of study-trial orientation. Interference is obtained even when the study-trial context emphasizes phonemic information and subjects are incidentally oriented to rating rhyme properties. However, this interference effect disappears when the test trial is delayed. In contrast, the results of Experiments 1-4 indicate that rhyme-related concepts are encoded and interfere with memory for the presented target only when subjects explicitly attend to the rhyme dimension. Once oriented, this interference effect is found after a relatively long delay. These differences are attributed to differences in attentional processing. The encoding of meaning-related concepts results from relatively automatic processes and the encoding of rhyme-related concepts requires subjects to attend to rhyme.