von Restorff revisited: Isolation, generation, and memory for order.

Abstract

The effects of isolation and generation on memory for order were investigated in 4 experiments. Experiments 1 and 2 examined the effect of isolation on order retention. Previous investigations in this area have yielded equivocal results. Experiments 1 and 2 revealed that isolation enhances memory for order: Isolated items were repositioned more accurately than comparable items in control lists. Experiments 3 and 4 investigated the effect of generation on order retention. These experiments revealed that generation can enhance, disrupt, or have no effect on memory for order, depending on the relative number of generated items appearing within a list. Implications of these results for general theoretical accounts of isolation effects in memory are discussed. A simplified version of the feature model (J. S. Nairne, 1990) is shown to provide a general account of isolation effects.

Short-term recall of order information: Influence of encoding and generation processes on distinctiveness, isolation, and background effects

“…We found negative effects of generation and background, as well as a trend toward a negative effect of isolation, but we also found a positive effect of distinctiveness in the same list, showing that these effects are distinguishable, even though they may be caused by similar processes, such as retrievalinduced forgetting. The extra processing explanation seems compatible with some of the theorizing of Kelley and Nairne (2001), who explained their findings in terms of Nairne's (1990) feature model. Although their pattern of results did not coincide with ours (e.g., they found a positive generation effect when only a single item in a list was generated and no background effect), they also refer to a special encoding of distinctive and generated items.…”

“…These findings of a negative distinctiveness effect contrast with the findings of Kelley and Nairne (2001), who used a different paradigm and observed both a positive generation effect and a positive isolation effect for order reconstruction in short-term recall. One reason for the negative effects of distinctiveness in the studies by Cunningham et al (1998) and Healy et al is that the distinctive letter was missing, so it was difficult or impossible to encode the letter at the time at which the letter segments were presented on a trial.…”

“…The procedures introduced in the present study, unlike those used in earlier studies (e.g., Kelley & Nairne, 2001), were able to separate the effects of generation from those of distinctiveness, isolation, and background. We eliminated the previously observed negative distinctiveness effect for a distinctive letter on an experimental trial (Cunningham et al, 1998;Healy et al, 2002) by providing overt opportunities for participants to encode the distinctive letter both before and during the presentation of the letter sequence.…”

“…However, the effects of distinctiveness or isolation on short-term memory and on memory for order information are more controversial (see, e.g., Kelley & Nairne, 2001). Some confusion about the effects of distinctiveness may arise because there are different ways to examine such effects.…”

An Isolation Effect in Serial Memory for Spatial Information

“…This isolation effect or von Restorff effect-as it is also commonly known following its discoverer (von Restorff, 1933)-is a robust phenomenon that has been replicated numerous times in many different methodological settings. Although an isolation effect has been found when an item is postcategorically distinct from its neighbours (e.g., a digit amongst syllables; Fabiani & Donchin, 1995), in most demonstrations the isolate has been precategorically (or perceptually) distinct, in terms of, for example, its colour (e.g., Huang & Hynum, 1970;Rosen, Richardson, & Saltz, 1962) or size (e.g., Huang & Hynum, 1970;Kelley & Nairne, 2001). Such effects in which isolation is implemented through precategorical attributes suggest that the phenomenon is unlikely to be related specifically to verbal Correspondence should be addressed to Katherine Guérard, É cole de psychologie, Université Laval, Québec, G1K 7P4, Canada.…”