Part-list cuing as instructed retrieval inhibition

The reexposure of a subset of learned material as a retrieval cue can impair recall of the remaining material. Like part-list relearning--the reexposure of learned material for additional learning--this part-list cuing is often assumed to be the result of output order biases at test, caused by the increased strength of the reexposed material. We directly compared the effects of cuing and relearning when controlling for output order biases. In addition, we compared the two forms of reexposure with the effect of part-list retrieval. Both part-list cuing and part-list retrieval reduced recall performance for the remaining material. By contrast, part-list relearning had no such detrimental effect. These results indicate that the effect of reexposure depends on whether material is reexposed as a cue or for relearning, suggesting that part-list cuing reflects an instructional effect. Evidence is provided that part-list cuing leads to instructed covert retrieval of cue items and causes retrieval inhibition of noncue items, similar to how overt retrieval inhibits nonretrieved items.     

Influences of intentional and unintentional forgetting on false memories

In 2 experiments, we examined the interplay of 2 types of memory errors: forgetting and false memory--errors of omission and commission, respectively. We examined the effects of 2 manipulations known to inhibit retrieval of studied words--directed forgetting and part-list cuing--on the false recall of an unstudied "critical" word following study of its 15 strongest associates. Participants cued to forget the 1st of 2 studied lists before studying the 2nd recalled fewer List 1 words but intruded the missing critical word more often than did participants cued to remember both lists. By contrast, providing some studied words as cues during recall reduced both recall of the remaining studied words and intrusions of the critical word. The results suggest that forgetting can increase or decrease false memories, depending on whether such forgetting reflects impaired access to an entire episode or retrieval competition among elements of an episode.     

Influences of part-list cuing on different forms of episodic forgetting

Across 3 experiments, we examined the interplay of part-list cuing and forgetting, employing 3 different methods to induce episodic forgetting-list--method directed forgetting, context-dependent forgetting, and proactive interference. For each form of forgetting, participants were asked at test to recall the target items of a previously studied list in the presence or the absence of the list's remaining items serving as retrieval cues. We found such part-list cuing to amplify the forgetting in proactive interference but to diminish the forgetting in list-method directed forgetting and context-dependent forgetting. These results show that the effects of part-list cuing on forgotten memories depend critically on the circumstances surrounding the forgetting. If the forgetting reflects impaired access to the original encoding context, as has been suggested in list-method directed forgetting and context-dependent forgetting (but not in proactive interference), part-list cues improve access to forgotten memories; if the forgetting does not reflect such a contextual effect, no such beneficial effects emerge, and access to forgotten memories may even be impaired.     

Impaired directed forgetting in abstinent heroin addicts

Drug-related memories persist long into abstinence and are potent elicitors of drug craving and relapse. We report two experiments examining whether heroin-dependent individuals are impaired in intentionally suppressing drug-related memories. Experiment 1 adopted the Item paradigm where addicts and healthy controls were presented with a list of words each followed by a remember or forget cue. Experiment 2 adopted the List paradigm where they studied one list of items and were then split into a remember group and a forget group. Both groups studied a second list, except that the forget group was told to forget the first list. Compared with controls, addicts showed a reduced directed forgetting effect in the Item method and a total absence of one measure of directed forgetting in the List method (List 2 benefits). Results indicate that heroin addicts are impaired in directed forgetting and that the deficits are likely associated with memory encoding as opposed to retrieval. Possible problems include reduced ability in actively suppressing/stopping encoding of irrelevant information into memory or inability in changing/resetting encoding strategies. In neither experiment did the addicts show any differential directed forgetting effects between drug-related words and neutral words, indicating the generic nature of their intentional forgetting deficits.     

Directed forgetting in young children: Evidence for a production deficiency

When people are cued to forget a previously studied list of items and to learn a new list instead, such cuing typically leads to forgetting of the first list and to memory enhancement of the second. In two experiments, we examined such listwise directed forgetting in children (and adults), using a forget cue that placed either high emphasis or low emphasis on the need to forget. In the low-emphasis condition, (adult-like) List 1 forgetting was present in fourth graders, but not in first graders (and kindergartners); in contrast, in the high-emphasis condition, (adult-like) List 1 forgetting was present from first grade on. Only fourth graders showed (adult-like) List 2 enhancement, regardless of task instruction. The finding that first graders showed List 1 forgetting only in the high-emphasis condition points to a production deficiency in first graders’ directed forgetting, suggesting that the children are capable of intentional forgetting but fail to do so spontaneously. The finding that first graders showed List 1 forgetting without List 2 enhancement suggests that the two directed-forgetting effects are mediated by different processes with different developmental trajectories.     

定向遗忘中提取抑制的机制：成功提取引起抑制

两个实验采用无关材料考察了字表方式下提取诱发遗忘解释定向遗忘中提取抑制的可能性。在实验中,学习完两个字表后,对字表2 进行不同次数（0、1、3次）的提取练习以考察是否会增强定向遗忘效应以及定向遗忘效应是否随着提取练习次数的增加而增强。实验一中,字表2提取练习是要求被试回忆字表2项目,不给予线索提示。在实验二中,采用词干补笔测验的形式对字表2进行提取练习,词干补笔测验保证了对字表2项目的成功提取。研究结果发现,只有在实验二中对字表2的成功提取练习增强了定向遗忘效应,从而表明成功提取可以解释定向遗忘中的提取抑制     

Retrieval-induced forgetting and part-list cuing in associatively structured lists

Using DRM lists (Roediger & McDermott, 1995) in two experiments, we compared the effects of retrieval practice on a subset of the items and of the presentation of those items as retrieval cues at test on recall of the lists' critical items. In Experiment 1, the critical items were part of the studied lists, thus addressing these items' veridical recall; in Experiment 2, they were not studied, thus addressing these items' false recall. Three major results emerged. First, retrieval practice and part-list cuing reduced both veridical and false recall. Second, the two manipulations induced an integration effect in veridical recall, with substantial forgetting in lists with low false recall levels and no forgetting in lists with high false recall levels. Third, retrieval practice and part-list cuing created the same effects on recall, qualitatively and quantitatively. These results suggest that the detrimental effects of retrieval practice and part-list cuing were mediated by similar mechanisms. They are consistent with the view that not only retrieval-induced forgetting, but also part-list cuing is caused by inhibitory processes.     

Unblocking memory through directed forgetting

The ability to remember an item can be blocked, or negatively primed, by exposure to related items. For example, ALLERGY is less likely to be generated given the word fragment A_L_ _GY if one is first exposed to ANALOGY. We examined whether this memory blocking effect is influenced by list-method directed forgetting. A total of 144 participants learned two lists of items, each consisting of words that were designed to negatively prime performance on a subsequent word fragment completion task. Participants who were told to forget List 1 before learning List 2 suffered significantly less memory blocking owing to the negative primes from List 1 than participants who were told to remember List 1. These results suggest that directed forgetting can modify the memory blocking effect by affecting the accessibility of information in memory.     

Source‐monitoring accuracy across repeated tests following directed forgetting

The repeated recall of items from lists that participants were earlier instructed to either remember or to forget was examined in two experiments. RR participants (those instructed to remember both lists they were presented) tended to recall more List 1 items than FR participants (those instructed to forget the first list and to remember the second list). FR participants recalled more List 2 items than did RR participants, but only when directed to report those items (Experiment 1), not when directed to report items from both lists (Experiment 2). Participants experienced difficulty correctly reporting the list source of items they recalled and incorrect source recall increased across tests, showing hypermnesia. This later result underscores the need for caution when assessing the accuracy of information retrieved from multiple sources across repeated tests. Together, the data patterns provide support for the retrieval dynamics account of hypermnesia, the context‐change account of directed forgetting, and limited support for the retrieval inhibition view of directed forgetting.     

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.     

情绪对连续事件定向遗忘的影响

本研究采用项目法定向遗忘范式以中性和负性连续事件的视频为实验材料, 通过2个实验考察了情绪对连续事件定向遗忘的影响, 并进一步探讨了情绪对细节记忆和要义记忆的定向遗忘的影响。结果发现, 情绪可以消除细节记忆的定向遗忘效应, 而仅有要义记忆的定向遗忘效应则主要受到事件连续性而非情绪的影响。     

The influence of directional associations on directed forgetting and interference

Two experiments examined how cross-list directional associations influenced list-method directed forgetting and the degree of interference observed on each list. Each List 1 item had a (a) bidirectionally related item on List 2 (chip <----> potato), (b) forward association with an item on List 2 (chip --> wood), (c) backward association from an item on List 2 (chip <-- chisel), or (d) no relationship with List 2 items. The results revealed that associative relationships that eliminated retroactive interference in the baseline condition also eliminated the directed forgetting costs. In contrast, associative relationships did not affect List 2 recall in the forget group, which remained unchanged across experimental conditions. However, certain conditions reduced proactive interference in the remember group, thereby eliminating the benefits of directed forgetting. The directed forgetting costs and benefits were observed independently of each other. The authors propose that these effects emerged from a combination of item and context strengthening induced by different associative directions.     

有意遗忘的脑机制

有意遗忘是指个体主动忘记无用和过时的信息,本质是记忆的主动抑制,包括定向遗忘和压抑遗忘。在定向遗忘中,记忆抑制既发生在编码阶段也发生在提取阶段,脑机制研究支持编码抑制理论和提取抑制理论;在压抑遗忘中,think和No-think所激活的脑区不同,No-think引起前额区域的激活增强和海马的激活减弱。未来应开展定向遗忘和压抑遗忘的脑机制差异研究,注重记忆抑制和其他心理活动抑制之间的差异研究,关注创伤个体的有意遗忘研究,拓展记忆控制神经网络的可塑性研究。     

List-method directed forgetting: Evidence for the reset-of-encoding hypothesis employing item-recognition testing

In list-method directed forgetting (LMDF), people are cued to forget a previously studied item list (List 1) and to learn a new list of items (List 2) instead. Such cuing typically enhances memory for the List 2 items, in both recall and (sometimes) item-recognition testing. It has recently been hypothesized that the enhancement effect for List 2 items (partly) reflects the result of a reset-of-encoding process. The proposal is that encoding efficacy decreases with an increase in study material, but the forget cue can reset the encoding process to make the encoding of early List 2 items as effective as the encoding of early List 1 items. An experiment is reported that examined the reset-of-encoding hypothesis with item-recognition testing, examining influences of items' serial learning position on the effects of the forget cue. Item-recognition tests were conducted separately for the two lists. Consistent with the reset-of-encoding hypothesis, the results showed strong enhancement effects for early List 2 items, but hardly any enhancement effects for middle and late List 2 items. Like in previous item-recognition studies, no cuing effects were found for List 1 items. The results support two-mechanism accounts of LMDF, which assume a critical role for a reset-of-encoding process for List 2 enhancement.     

On the durability of retrieval-induced forgetting

Information retrieved from memory becomes more recallable in the future than it would have been otherwise. Competing information associated with the same cues, however, tends to become less recallable, at least for a while. Whether the latter effect—referred to as retrieval-induced forgetting—is persistent, or only transient, is the question that motivated the present research. Participants studied category-exemplar pairs, practised retrieving other exemplars of half the categories, and, finally, were tested for their ability to recall initially studied exemplars after a 5-min delay (half the items) and after 1 week (the remaining items). In addition, for half the categories, opportunities to restudy the exemplars were provided between cycles of retrieval practice. The results demonstrate that retrieval-induced forgetting can persist for as long as a week, but that such forgetting is eliminated when participants are intermittently reexposed to unpractised items during retrieval practice.     

部分线索对记忆提取的影响:认知抑制能力的作用

在回忆时,以刚刚学过的部分项目作为提取线索,被试的回忆成绩反而比没有任何线索时的回忆成绩差,这一现象被称为部分线索效应。该效应通常被认为是抑制执行控制过程对非线索项目记忆表征强度抑制的结果。本研究以Stroop效应量(实验1)和工作记忆容量(实验2)为指标,从个体差异角度考察了认知抑制能力对部分线索效应的影响。结果发现,Stroop效应量与部分线索效应各指标呈显著负相关,Stroop效应量越小,部分线索效应各指标的值越大;工作记忆容量与部分线索效应各指标呈显著正相关,高工作记忆容量个体的部分线索效应各指标的值也更大。结果表明,认知抑制能力越强,部分线索对回忆的破坏作用越大,研究结果支持部分线索效应的提取抑制假说。     

Recall order determines the magnitude of directed forgetting in the within-participants list method

In three experiments, we investigated the effect of recall order on directed forgetting when the within-participants list method is used. Experiment 1 showed that participants tend to recall to-be-remembered (R) items before to-be-forgotten (F) items when they can recall items in any order. In Experiment 2, recall order was manipulated (F-R or R-F). The results showed that only the R-F order led to directed forgetting. Finally, in Experiment 3, recall order was also manipulated, and half of the participants were explicitly instructed to use a relational strategy when both F and R items were presented. Again, only the R-F order led to directed forgetting. These results demonstrate that directed forgetting under the list method hinges on the output order in which participants recall the F and R information. Thus, output order should be taken into account by researchers investigating specific mechanisms that lead to directed forgetting.     

Intact retrieval inhibition in children’s episodic recall

Young children are assumed to be inefficient inhibitors in a number of cognitive tasks. In two experiments, we examined whether such deficits extend to children's episodic recall. We used two inhibition paradigms: retrieval-induced forgetting, the detrimental effect of retrieval practice with a subset of learned items on recall of the unpracticed items, and part-list cuing, the detrimental effect of the presentation of a subset of learned items on recall of the remaining items. In both experiments, the inhibitory effects were compared across three age groups: first or second graders, fourth graders, and young adults. The two children groups showed the same amounts of retrieval-induced forgetting and part-list cuing as the adult group, pointing to intact retrieval inhibition in young children's episodic recall. These results parallel very recent results on older adults' episodic recall, suggesting that both retrieval-induced forgetting and part-list cuing develop early in life and remain intact for the greater part of the lifespan.     

List-method directed forgetting: The forget cue improves both encoding and retrieval of postcue information

In list-method directed forgetting, people are cued to forget a previously studied item list and to learn a new list instead. Such cuing typically leads to forgetting of the first list and to memory enhancement of the second, referred to as list 1 forgetting and list 2 enhancement. In the present study, two experiments are reported that examined influences of items' serial learning position in a list and the two lists' output order on list-method directed forgetting. The results show that list output order influences list 2 enhancement but not list 1 forgetting. The enhancement was higher when list 2 was recalled first than when list 1 was recalled first and, in both cases, was higher for early list 2 items than for middle and late list 2 items. In contrast, the forgetting was equally present for all list 1 items and did not depend on the two lists' output order. The findings suggest that two separate factors can contribute to list 2 enhancement: one (encoding) factor that is restricted to early list 2 items and does not depend on list output order, and another (retrieval) factor that pertains to all list 2 items and varies with the two lists' output order. A new two-mechanism account of directed forgetting is suggested that reconciles previous (encoding or retrieval) views on list 2 enhancement.     

Repetition effects in directed forgetting: evidence for retrieval inhibition

Four experiments were conducted in support of a role for memory retrieval inhibition in directed forgetting. In each experiment, subjects were presented a list of words, some of which they were instructed to remember and some of which they were instructed to forget. After a recall test for all the words, the list was repeated. This time, however, all the words were presented with instructions that they be remembered. The improvement in recall from Trial 1 to Trial 2 was greater for the “forget” (F) words than for the “remember” (R) words. This difference was not due to a memorization-difficulty, item-selection effect (Experiment 2), a differential priority for rehearsal or output position given to the F items on Trial 2 (Experiment 3), or the greater number of F items left to be learned after Trial 1 (Experiment 4). Thus, the differential improvement from List 1 to List 2 for the F items was interpreted as a release of retrieval inhibition owing to the change in cue from forget to remember.