Having shaved a kiwi fruit: Memory of unfamiliar subject-performed actions

Summary

In an experiment with young and elderly adults, memory of unfamiliar actions performed by the subjects was compared with memory of actions low and high in familiarity, in order further to assess the role of a knowledge base as regards memory material encoded by enacting. Memory of similar actions encoded verbally was also assessed. The findings showed that the type of encoding, as well as familiarity, determined free-recall memory performance. The highest free-recall scores were found for familiar actions encoded by performance, in both an immediate and a delayed free-recall test. Recognition memory was also enhanced by enacting, whereas the influence of familiarity with an item upon recognition performance was limited to actions encoded verbally. The role of familiarity in recognition performance of actions encoded verbally was reversed compared with that in free recall, in that recognition of unfamiliar actions was most effective. Moreover, age-related memory deficits were found in this study. Elderly adults showed a consistently lower level of performance than younger subjects in both types of free-recall test and in the recognition test. This effect of age was found regardless of the type of encoding, demonstrating that age-related memory differences are not compensated by motor encoding. The age effect was also found regardless of familiarity with the items, and was most significant for unfamiliar actions. This demonstrates that elderly adults have particular difficulty in processing unfamiliar memory material.