David R. Basden

A comparison of group and individual remembering : Does collaboration disrupt retrieval strategies ?

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.

Costs and benefits of collaborative remembering

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

Transmitting false memories in social groups

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.

Part-set cuing of order information in recall tests

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.

The role of retrieval practice in directed forgetting.

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.

Part-list reexposure and release of retrieval inhibition ☆

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.

Retrieval inhibition in directed forgetting and posthypnotic amnesia

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).

Memory and organization in elderly subjects

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 Einsteins (1981) distinction between item-specific and relationship processing, and an alternative interpretation was offered.

Recall and clustering as a function of categorization and distance between related items

Lists composed of six pairs of categorically related associates (CA) and six pairs of categorically unrelated associates (UA) were presented to Ss for free recall. Presentation order was varied between groups by controlling the number of items (0, 1, 2, 3, or 5) intervening between associates. Recall and clustering were greater for CA words than for UA words, but only with noncontiguous presentation of associates. The locus of the recall effect was in the number of items recalled per pair rather than in the number of pairs represented in recall. The results were considered supportive of the hypothesis that in the absence of blocked presentation, categorically related items are more likely to be experienced contiguously (functional contiguity) than are categorically unrelated items.

An introductory psychology laboratory system featuring inexpensive time-shared record-keeping

At California State University, Fresno, the introductory psychology lecture sections operate independently of the laboratory system. Each week, the faculty supervisor prepares the teaching assistants to instruct the following week’s laboratory presentation. The department’s subject pool is also administered through the laboratory system. At the end of the semester, the lecture instructors are supplied with laboratory grades for incorporation into the overall course grades. Record-keeping, especially for the subject pool, was a major problem until we computerized its various components. We use one of the university’s time-sharing systems for this purpose, which has proven cost effective, secure, and quite efficient.