Proceedings of the Annual Meeting of the Cognitive Science Society

In a series of studies, Schooler and Engstler-Schooler (1990) showed that verbalization of previously encountered non-verbal stimuli can impair subsequent memory performance. The present study investigates the possibility that the verbal disruption of non-verbal processes, called verbal overshadowing, m a y be applied to implicit learning, i.e., where what is learned is difTicult to verbalize. One frequently studied area of implicit learning is artificial grammars (e.g., Reber & Lewis, 1977). In the artificial grammar research, it has been shown that subjects can learn information about regularities in letter strings generated from a fmite state grammar, as measured by transfer tests, while being unable to usefully state what those regularities are. The apparent disparity between subjects' competent performance on artificial grammar tasks and their inabiUty to explain the rules of those tasks suggests the possibility that verbalization following memorization of artificial grammar strings may impair subjects' performance on a transfer task. In this study, subjects memorized a subset of grammatical letter strings, then half of them verbalized the rules they learned during memorization. The verbal subjects performed significantly worse than the non-verbal subjects on a transfer task, providing preliminary evidence that verbalization may impair transfer when the learned information is difficult to verbalize