Baseline performance and learning rate of procedural and declarative memory tasks: younger versus older adults

Twenty-five older and 25 younger adults were compared on declarative (i.e., Rey Auditory-Verbal Learning Test and Visual Pair Associations) and procedural (i.e., Tower of Hanoi puzzle and Porteus mazes) learning tasks. A dissociation between learning rate on declarative and procedural tasks was demonstrated for the elderly participants. The younger group showed a steeper learning rate than the older group on the declarative tasks. By contrast, the learning rate of both groups on the procedural tasks did not differ consistently, whether the measure was number of errors/moves or time elapsed (with one exception in which the older group showed a steeper learning rate than the younger group). The younger group's baseline performance was better than that of the older group on all tasks employed in this study. These results reinforce the importance of distinguishing between baseline performance and the rate of learning on procedural learning tasks.