Developmental differences in implicit and explicit memory performance

Cognitive theorists differentiate between two forms of memory. Explicit memory is demonstrated in tasks that require individuals to deliberately remember information that was studied during a prior learning episode. Implicit memory is demonstrated in tasks that do not require any reference to the prior learning episode; individuals are merely asked to perform a task that is sensitive to the effects of prior experience. The present study explored developmental differences in implicit and explicit memory test performance by using two different types of implicit and explicit memory tasks (perceptual and conceptual) and requiring two types of processing (again, perceptual and conceptual) during study. Performance of preschool children, elementary school students, and college students was compared on a series of implicit and explicit memory tasks. Performance on the explicit memory task that relied on conceptual processing showed the expected improvement across age groups. In contrast, performance on the explicit memory task that relied on perceptual processing as well as that on both types of implicit memory tasks showed no developmental change. Results from the two types of processing manipulations demonstrated that perceptual processing during study led to better memory performance than conceptual processing for both the implicit and explicit tasks that relied on perceptual processing. Conversely, conceptual processing during study led to better memory performance than perceptual processing on an explicit memory task that relied on conceptual processing. Performance on an implicit memory task that relied on conceptual processing was affected equally by both types of study processing. The results are discussed in terms of transfer-appropriate processing (Roediger & Blaxton, 1987b) and unitization and grouping processes (Graf & Schacter, 1989).