Dissociation of implicit and explicit memory tests: effect of age and divided attention on category exemplar generation and cued recall.

In this article, we report an experiment that provides further evidence concerning the differences between explicit and implicit measures of memory. The effects of age and divided attention on the implicit conceptual test of category exemplar generation (CEG) were compared with their effects on the explicit test of cued, recall, where the category names served as cues in both tasks. Four age groups (20-35, 40-55, 60-75, and 76-90) were compared. Half of the subjects were also required to carry out a secondary letter-detection task during the learning phase. Cued recall performance was significantly impaired by increased age and imposition of the secondary task. In contrast, the CEG task was unaffected by these two factors. These results suggest that implicit conceptual tasks and explicit memory tasks are mediated by different processes. This conclusion opposes those of previous studies that showed that experimental manipulations (level of processing, generation, organization) influenced these two kinds of memory tests in a similar way.