Theoretical implications of the mnemonic benefits of perceptual interference.

Abstract

How should interfering with the perception of items during study affect memory for those items? Recent research by Nairne (1988) and Hirshman and Mulligan (1991) has demonstrated that backward pattern masking during study enhances later memory. This article examines whether traditional explanations of encoding benefits, including rehearsal, visual distinctiveness, and encoding effort, can account for this result. No evidence was found for any of these hypotheses. An explanation that focuses on the compensatory processing of higher level perceptual representations is proposed. This explanation provides a plausible explanation of the results of 7 experiments. The article concludes with a discussion of the implications of the explanation for perceptual priming and other manipulations of perceptual interference. How does interfering with the perception of items during study affect memory for those items? Nairne (1988) and Hirshman and Mulligan (1991) recently investigated this question using visual masking. These investigators examined memory performance on items presented in two study conditions. In the control or intact condition items were presented for 2.5 s. In the experimental or interference condition items were presented briefly (i.e., 100 ms) and then followed with a backward pattern mask (i.e., a row of Xs) presented for 2.4 s. The mask obscures the visual features of the study item, interfering with its perception. Surprisingly, these studies have demonstrated that interfering with perception using visual masking can actually improve memory performance. Nairne (1988) reported an advantage for the interference condition in recognition memory. Hirshman and Mulligan (1991) replicated Nairne's recognition memory results and demonstrated that this effect also occurs in free recall.1 These results seem surprising from several perspectives. First, many classical (Atkinson & Shiffrin, 1968; Waugh &