Implicit and Explicit Learning in Aged and Young Adults

ABSTRACT

There is a wealth of evidence that learning ability declines with age. In almost all of the studies however, the performance measures employed are explicit, even though research has consistently indicated that aged adults have well preserved implicit learning ability. This suggests that under certain circumstances aged adults should be at no great learning disadvantage in comparison to young adults. This experiment used the artificial grammar-learning paradigm, developed by Reber, in a 2 X 2 factorial design that involved systematic manipulation of grammatical complexity and rule provision. The study explored how each combination of conditions influenced explicit or implicit learning and the relationship between learning style and performance by aged and young adults. Learning was assessed primarily by recognition accuracy, involving correct and incorrect grammar exemplars. However, reaction time, error pattern, reliability, and verbal report data was also collected as a way of confirming and providing added detail on learning performance patterns. Aged adults, irrespective of experimental learning conditions, evidenced a remarkably consistent reaction time deficit. In contrast, the accuracy differential between age groups varied markedly across the four treatments. The most salient contrast occurred between complex grammar, without rules, where there was no difference in accuracy between the two age groups and simple grammar, with rules, where the difference was greatest. This change in learning performance between these two conditions indicates that aged adults will learn as well as young adults in situations where the knowledge domain is conducive to implicit learning.

ACKNOWLEDGEMENTS

We would like to thank Sylvie Noel and Danny Bose-Jelinek for their generous assistance in writing the computer program that controlled the presentation of the grammar stimuli. We received valuable statistical advice and assistance from Bob Kane and Mike Phillips. Finally we would like to thank all the people who gave of their time to participate in this study.