Perceptual fluency, that is, the ease with which people perceive information, has diverse effects on cognition and learning. For example, when judging the truth of plausible but incorrect information, easy-to-read statements are incorrectly judged as true while difficult to read statements are not. As we better remember information that is consistent with pre-existing schemata (i.e., schema congruency), statements judged as true should be remembered better, which would suggest that fluency boosts memory. Another line of research suggests that learning information from hard-to-read statements enhances subsequent memory compared to easy-to-read statements (i.e., desirable difficulties). In the present study, we tested these possibilities in two experiments with student participants. In the study phase, they read plausible statements that were either easy or difficult to read and judged their truth. To assess the sustainability of learning, the test phase in which we tested recognition memory for these statements was delayed for 24 h. In Experiment 1, we manipulated fluency by presenting the statements in colors that made them easy or difficult to read. In Experiment 2, we manipulated fluency by presenting the statements in font types that made them easy or difficult to read. Moreover, in Experiment 2, memory was tested either immediately or after a 24 h delay. In both experiments, the results showed a consistent effect of schema congruency, but perceptual fluency did not affect sustainable learning. However, in the immediate test of Experiment 2, perceptual fluency enhanced memory for schema-incongruent materials. Thus, perceptual fluency can boost initial memory for schema-incongruent memory most likely due to short-lived perceptual traces, which are cropped during consolidation, but does not boost sustainable learning. We discuss these results in relation to research on the role of desirable difficulties for student learning, to effects of cognitive conflict on subsequent memory, and more generally in how to design learning methods and environments in a sustainable way.
The role of stimulus type in list length effects in recognition memory
