In list-method directed forgetting, reexposure to forgotten List 1 items has been shown to reduce directed forgetting. proposed that reexposure to a few List 1 items only during a direct test of memory reinstates the entire List 1 episode. In the present experiments, part-list reexposure in the context of indirect as well as direct memory tests reduced directed forgetting. Directed forgetting was reduced when 50% or more of the items were reexposed, and was intact when only 25% were reexposed. Furthermore, part-list reexposure appeared to reinstate only reexposed items-not the entire List 1 episode.

Three experiments tested the possibility that retrieval-induced forgetting is responsible for directed forgetting with the list method. In Experiments 1 and 2, additional List 2 retrieval practice was given to determine whether this would increase directed forgetting. In Experiment 1 all items came from a single category, and in Experiment 2 unrelated words were used. In Experiment 3 additional List 2 study accompanied List 2 retrieval practice. There was no evidence that List 2 retrieval practice, with or without additional List 2 study, affected the magnitude of directed forgetting. It was argued that retrieval-induced forgetting could not account for these results. Accounts with greater viability include retrieval strategy disruption and a modified version of the dissociation hypothesis.

Serra and Nairne (2000, Experiment 3) showed that serial reconstruction of lists was better with consistent part-set cues (cues presented in their original positions) and worse with inconsistent part-set cues (cues presented in different positions) than with no cues. To determine if those results can be generalized beyond serial reconstruction, the present research examined the effect of consistent and inconsistent cues on serial and free recall. In Experiment 1, serial recall was facilitated with consistent cues but impaired with inconsistent cues. In Experiment 2, free recall was relatively little influenced by cuing condition. In Experiment 3, part-set cuing inhibition occurred when cues were segregated from the recall protocol but cues were not always inhibitory when cues were integrated. It was concluded that the effect of cues on item memory may be mediated by their effect on order memory.

In 2 experiments, subjects studied word lists drawn from Roediger and McDermott (1995) and then participated in perceived group recall (PGR) tests that were intended to lead each subject to believe that she or he was participating in collaborative recall in a 4-person group. Some of the lists were followed by PGR tests containing the nonpresented critical word, some lists were followed by PGR tests not containing the nonpresented critical word, and some lists were not followed by PGR tests. Subjects then completed individually administered recall tests and subsequent immediate or delayed recognition tests that required remember or know judgments. The major finding was that critical words contained within PGR tests were as likely to be falsely recalled, recognized, and consciously remembered as original list items. These findings show that false memories can be socially transmitted.

Collaborative inhibition, the poorer memory performance of collaborative groups as compared with nominal (noninteracting) groups was measured in the free recall of categorized lists. In Experiment 1, collaborative inhibition was present in four-person groups, but not in pairs of two-person groups, where each was compared with performance in four-person nominal groups. However, on a final individual free recall test, members of two- and four-person collaborative groups recalled a higher proportion of the list than members of nominal groups. In Experiment 2, recall in three-person collaborative groups was less than in three-person nominal groups but only on the first of three successive study-test trials. On the final individual free recall test, members of collaborative groups recalled more words than members of nominal groups. Despite inhibiting recall and reminiscence, collaboration benefits remembering when collaborators are subsequently tested individually. Copyright © 2000 John Wiley & Sons, Ltd.

M. S. Weldon and K. D. Bellinger (1997) showed that people who collaborate on a recall test (collaborative group) perform much more poorly than the same number of people tested individually (nominal group). Four experiments tested the hypothesis that retrieval-strategy disruption underlies this collaborative inhibition when categorized lists are studied. Collaborative groups performed worse than nominal groups when categories were large (Experiment 1) and when category names were provided at recall (Experiment 2). However, collaborative- and nominal-group recall were equivalent when participants retrieved nonoverlapping parts of the list (Experiment 3) and when participants were forced to organize their recall by category (Experiment 4). Clearly, disorganized retrieval can account for collaborative inhibition with the materials and procedures used here.

Earlier we reported (Basden, Basden, Bryner, ...Thomas, 1997) that, in comparison with nominal groups (three people tested individually), three-person collaborative groups recalled fewer presented words but intruded more nonpresented words. In the present research, Experiment 1 showed that when presented words were associatively related to critical nonpresented words, collaboration inhibited recall of presented words but did not influence recall of critical nonpresented words. Experiment 2 showed that with categorized lists, recall of high taxonomic frequency critical nonpresented words was greater for collaborative groups than for nominal groups. Collaboration did not inhibit recall of presented words, presumably because guessing supplemented recall in collaborative groups. Greater false recall in collaborative than in nominal groups appears to result from activation of superordinate-to-item associations rather than item-to-item associations.

Three experiments contrasted the effects of directed forgetting instructions when given by item and given by list. In Experiment 1, which involved free recall of a single-category list, directed forgetting was greater with the item method than with the list method when the study format was pictures or words whose referents were imaged (these encouraged item-specific processing), but not when the study format was words not imaged (this encouraged relational processing). In Experiment 2, directed forgetting was observed with the item method but not with the list method in an indirect test of general knowledge. In Experiment 3, "Recollect" judgements showed directed forgetting with the item method but not with the list method. "Know" judgements did not show directed forgetting with either method. These experiments show that the mechanisms underlying directed forgetting differ for the item and list methods.

Part-list cuing inhibition is diminished recall for the remainder of a studied list when part of that list is provided on the recall test. In Experiments 1-3, participants formed arbitrary subcategories. Inhibition was absent when cues were consistent with those subcategories but present when cues were inconsistent with them. In Experiment 4, participants failed to adapt to part-list cuing, despite its presence on several training trials. In Experiment 5, a subcategorical retrieval strategy consistent with the presence of cues effectively eliminated inhibition whether that strategy was suggested at study or at recall. Two findings indicated that part-list cuing may be inconsistent with some retrieval strategies that produce recall segregated by subcategory. Most findings supported the strategy disruption position that inhibition results when a whole-list retrieval strategy is abandoned for a less effective part-list retrieval strategy.

Cross-language priming in word-fragment completion was investigated from the perspective of the transfer appropriate processing (TAP) framework as extended by Weldon (1991). Both proficient and beginning bilinguals were tested when study conditions were presented in mixed or unmixed lists. Spanish words were read, mentally translated, or translated and written prior to an English word fragment completion test. Consistent with the revised TAP framework, primed fragment completion increased as the number of study-activated processing components increased. For proficient bilinguals, priming was significant for items read in pure lists but not for items read in mixed lists.

In Experiment 1, subjects received either by word or by list directed forgetting or posthypnotic amnesia instructions. Recall and recognition performance of subjects who received directed forgetting instructions was consistent with previous findings reported by Basden, Basden, and Gargano (1993), with subjects who received by word instructions showing both recall and recognition deficits for to-be-forgotten items. By contrast, subjects who were given by list instructions showed recall but no recognition deficits, which suggests that although differential encoding underlies word method directed forgetting, retrieval inhibition underlies list method directed forgetting. Subjects who received posthypnotic amnesia instructions (irrespective of method of delivery used) showed recall deficits but no recognition deficits, which suggests that retrieval inhibition underlies posthypnotic amnesia. In Experiment 2, recognition scores were lower with public (oral) tests than with private (written) tests, and recovery was equivalent for to-be-forgotten and to-be-remembered items. The results are interpreted as inconsistent with the differential tagging mechanisms proposed by Huesmann, Gruder, and Dorst (1987).

Older adults (ages 67-91) and younger adults (ages 16-30) sorted 100 unrelated words into as many categories as they chose, provided labels for those categories, and were given a surprise recall test with or without the labels as retrieval cues. The older adults recalled fewer words, fewer categories, and fewer items per category than the younger adults. Though generally facilitory, cuing did not reduce the age-related differences in recall performance. Clustering was equivalent for the two age groups. The correlation between number of categories used in sorting and number of words recalled was significant for the young adults only, replicating and extending the results reported by Worden and Meggison (1984). The results were discussed in terms of Hunt and Einstein's (1981) distinction between item-specific and relationship processing, and an alternative interpretation was offered.

Directed forgetting has been studied by instructing Ss to forget either (a) an initial list or (b) individually selected words. Differential encoding was hypothesized to be responsible for word-method directed forgetting, and retrieval inhibition for list-method directed forgetting. In Experiments 1 and 2, directed forgetting was observed in recognition with the word method but not with the list method. Release from directed forgetting occurred in final recall after recognition but only with the list method. These results are interpreted in terms of a theoretical framework that integrates distinctive-relational processing theory with revised generation-recognition theory. In Experiments 1-3, predictions from that framework were generally well supported on implicit and explicit retention tests that provided the same stimulus conditions. Consistent with processing theory, list-method directed forgetting was absent on data-driven or conceptually driven implicit tests, and word-method directed forgetting was absent on data-driven implicit tests.