Item method directed forgetting diminishes false memory

Directed forgetting may reduce DRM false memory illusion by interfering with meaning processing. Participants were presented with a list composed of six 10-word semantically associated sub-lists, and they were either (a) asked to remember all list items of (b) asked to remember all associates from sub-lists and to forget all associates from other sub-lists. All participants were requested to recall and recognise list items. Although directed forgetting effects have been previously reported only for true responses in the DRM paradigm with the list method, we also found directed forgetting for false responses with the item method. Such forgetting instructions reduced both verbatim and meaning processing, decreasing both the intrusion and the false alarm rate. These results are consistent with two-process explanations of DRM false memories, such as fuzzy-trace theory, and add to our understanding of false memory editing.     

Can intentional forgetting reduce false memory? Effects of list-level and item-level forgetting

This study examined whether false memory produced by the learning of lists of categorized and associative materials could be reduced by directed forgetting. The number of items within a list that participants were asked to remember or forget was manipulated, while the length of the list remained constant. Experiment 1a used categorized lists and Experiment 1b used associative lists; the participants performed immediate free recall and cued recall tests. For both the categorized and associative lists, the rate of false recall increased upon increasing the proportion of "forget" (F) words. After removing the immediate recall test, Experiment 2 found that intentionally forgetting part of the studied list reduced false memory, whereas forgetting the whole studied list did not. The results are discussed in terms of the list-level-vs.-item-level inhibition in semantic activation and the role of monitoring in reducing false memory.     

Self-evaluation as a moderating factor of strategy change in directed forgetting benefits

In list method directed forgetting, instructing people to forget a studied word list usually results in better recall for a newly studied list. Sahakyan and Delaney (2003) have suggested that these benefits are due to a change in encoding strategy that occurs between the study of the first list and the study of the second list. To investigate what might mediate such strategy change decisions, in two experiments we induced bothforget and remember participants to evaluate their memory performance on the two lists. In Experiment 1, they were asked to explicitly recall the items from the first list before studying the second list. In Experiment 2, after the study of the first list, the participants provided a rapid aggregate judgment of learning. Evaluation eliminated the differences between the forget and remember groups for the second list in both experiments, because the remember group achieved recall levels comparable to those for the forget group. The role of performance evaluation in mediating directed forgetting benefits is discussed.     

False memories are hard to inhibit: differential effects of directed forgetting on accurate and false recall in the DRM procedure

Directed forgetting research shows that people can inhibit the retrieval of words that they were previously instructed to forget. The present research applied the directed forgetting procedure to the Deese/Roediger and McDermott (DRM) recall task to determine if directed forgetting instructions have similar or different effects on accurate and false memory. After studying lists of semantically related words, some participants were told to forget those lists, whereas other participants were not. All participants were then shown additional lists to remember. Following study, all participants were asked to free recall as many of the studied words as possible, including those they were previously instructed to forget. Directed forgetting instructions inhibited the accurate recall of studied words, but not the false recall of nonstudied critical words, whether measured by a within-participant or between-participants design. Contrary to an implicit activation hypothesis, false memories survived instructions to forget. These findings were reviewed in terms of fuzzy trace theory and the activation/monitoring approach to false memory.     

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.     

Inhibition, Contextual Segregation, and Subject Strategies in List Method Directed Forgetting

This experiment tested alternative explanations of list method directed forgetting effects. Two word lists were studied by 135 subjects. Between lists, subjects were instructed to remember both lists (remember group), remember both lists as well as in which list words were studied (segregate group), or to forget the first list and remember the second (forget group). All subjects took both recall and recognition tests with test order varied between subjects. Among subjects who took the recall test first, the forget group showed a directed forgetting effect (poorer performance on List 1 than List 2) with both recall accuracy, recall typing time, and recognition reaction time measures. Contextual segregation of List 1 words by forget subjects was ruled out as a sufficient cause of the effect. Limited support was obtained for a differential rehearsal explanation of the effect. Within-group comparisons and findings of release from directed forgetting support inhibitory processes as the major cause of the directed forgetting effect.     

Retrieval practice can eliminate list method directed forgetting

It has recently been shown that retrieval practice can reduce memories’ susceptibility to interference, like retroactive and proactive interference. In this study, we therefore examined whether retrieval practice can also reduce list method directed forgetting, a form of intentional forgetting that presupposes interference. In each of two experiments, subjects successively studied two lists of items. After studying each single list, subjects restudied the list items to enhance learning, or they were asked to recall the items. Following restudy or retrieval practice of list 1 items, subjects were cued to either forget the list or remember it for an upcoming final test. Experiment 1 employed a free-recall and Experiment 1 a cued-recall procedure on the final memory test. In both experiments, directed forgetting was present in the restudy condition but was absent in the retrieval-practice condition, indicating that retrieval practice can reduce or even eliminate this form of forgetting. The results are consistent with the view that retrieval practice enhances list segregation processes. Such processes may reduce interference between lists and thus reduce directed forgetting.     

The Directed Forgetting Effect in Word-fragment Completion: An Application of the Process Dissociation Procedure

In three experiments, subjects were asked to remember and forget study words. In line with previous studies, a directed forgetting effect was observed in a word-fragment completion task: Instructions to remember increased the completion of target fragments compared with instructions to forget (Experiment 1). Using the process dissociation procedure (Jacoby, 1991), it appeared that instructions to remember increased the estimates of intentional influences of memory but did not affect the estimates of automatic uses of memory (Experiments 1, 2 and 3). This suggests that directed forgetting effects in word-fragment completion reflect the surreptitious influence of explicit memory in a nominally implicit memory task. However, a meta-analysis indicated that directed forgetting instructions affected automatic and intentional influences of memory in opposite directions. This finding casts doubt on the assumption of independence between automatic and intentional uses of memory. The implications for use of the process dissociation procedure are discussed.     

Examining the basis for illusory recollection: The role of remember/know instructions

Curiously, studies using the remember/know paradigm to measure recollective experience show that people often vividly remember events that never occurred, a phenomenon referred to asillusory recollection. Two experiments tested the hypothesis that false remember responses in the converging associates, or Deese/Roediger-McDermott (DRM) paradigm, reflect accurate memory for the study episode, rather than false recollection of critical lures. To test this hypothesis, we used standard remember instructions that emphasized recollection of the study context by allowing participants to use memory of surrounding list items as evidence for recollection, or we used modified instructions that did not include memory for surrounding list items as a basis for recollection. Results showed that, as compared with the standard instruction condition, the modified instructions selectively reduced reports of false remember responses to critical lures, but did not affect remember responses to studied items. By contrast, remember responses to critical lures were unaffected by an instruction condition that excluded the use of voice information as evidence for remembering. These results suggest that remember responses to falsely recognized items are driven partly by retrieval of studied items, rather than illusory recollection of the critical lures themselves. They further point to the importance of instructions in influencing subjective reports.     

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     

自我与有意遗忘现象

将自我参照效应的实验范式与字表方式的有意遗忘范式相结合,探讨有意遗忘在自我参照与他人参照条件下的异同。结果表明,在有意遗忘的研究范式下,自我参照加工和他人参照加工的回忆量之间不存在显著差异;但是自我参照条件下出现了有意遗忘现象,而他人参照加工条件下没有表现出有意遗忘现象。这表明,自我参照加工的材料,区辨性很高,因而有意遗忘的指导语激发的抑制作用对它有效,从而出现了遗忘现象。     

Impaired strategic regulation of contents of conscious awareness in schizophrenia

Conscious awareness comprises two distinct states, autonoetic and noetic awareness. Schizophrenia impairs autonoetic, but not noetic, awareness. We investigated the strategic regulation of relevant and irrelevant contents of conscious awareness in schizophrenia using a directed forgetting paradigm. Twenty-one patients with schizophrenia and 21 normal controls were presented with words and told to learn some of them and forget others. In a subsequent test, they were asked to recognize all the words they had seen previously and give remember, know or guess responses according to whether they recognized words on the basis of autonoetic awareness, noetic awareness, or guessing. Overall, patients showed the same degree of a directed forgetting effect as normal subjects. However, whereas the effect was observed both for remember and know responses in normal subjects, it was observed for know, but not for remember, responses in patients. These results indicate that patients with schizophrenia exhibit an impaired strategic regulation of contents of autonetic awareness for relevant and irrelevant information.     

Destructive effects of “forget” instructions

In two experiments, participants were given three lists of words to study and were told to (1) remember all three lists, (2) forget the first list immediately after studying it but try to remember the other two lists, or (3) forget the middle list immediately after studying it but try to remember the first and the last lists. In Experiment 1, unrelated word lists were used, whereas Experiment 2 replicated Experiment 1 with categorical lists. The results from both experiments showed that forgetting the middle list leads also to recall decrement for the first list, which was not intended for forgetting. The results are discussed in terms of the contextual change hypothesis of directed forgetting.     

内容与自我关联性对负性情绪记忆定向遗忘的影响

本研究使用消极情绪视频片段作为实验材料,采用词表法定向遗忘范式,用2个实验分别考察了内容与自我关联性对负性情绪要义和细节记忆的定向遗忘及其权衡的影响。研究结果表明：(1)内容关联性对定向遗忘几乎没有影响,在内容关联条件下,遗忘提示只增加了要义记忆没有增加细节记忆;(2)自我关联性对定向遗忘产生了影响,自我关联条件下出现了定向遗忘,而自我无关条件下定向遗忘消失;(3) 关联性对细节和要义记忆有不同的影响,表现出明显的要义-细节权衡。     

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 item and list methods of directed forgetting: test differences and the role of demand characteristics

In directed forgetting, the item method presents instructions to remember or to forget individual items; the list method presents a single mid-list instruction to forget the first half of the list. Initial free recall was better for remember (R) words than for forget (F) words under both methods. Offered 50 cents for each additional F word, subjects could recall almost no more items, eliminating a demand characteristics explanation. On a yes/no recognition test, only the item method showed directed forgetting. Retrospective instruction identification was good except for F words under the list method, where performance was at chance. There was no evidence of speed-accuracy tradeoff on the recognition or instruction identification tests. These results bring together the major findings concerning directed forgetting and support a method-based theoretical distinction.     

Directed forgetting of emotional words

Emotional material may induce processing limitations affecting memory performance. In the present study, the authors investigated how the emotional content of words influences the degree to which participants can be directed to forget them. In Experiment 1, the authors found that negative-valence words were recalled better when participants were told to forget them than when they were told to remember them. This effect was only obtained when a study-list of negative words was presented after the cue to remember or forget the first list. The effect was correlated with negative mood as assessed by the PANAS. Similar results were obtained in Experiment 2, in which the induction of negative arousal by a mild stressor abolished the directed forgetting of words when the following study list was comprised of negative words. These results support the idea that directed forgetting relies on cognitive control processes that may be disrupted by negative emotion.     

Effects of post‐cue interval on intentional forgetting

This study examined the effect of post‐cue interval on directed forgetting and suppression. Experiments 1 and 2 used the item method of directed forgetting. The interval between the cue to remember/forget (R/F) and the presence of the next item was manipulated. As the post‐cue interval increased, the rates of hits and ‘remember’ responses on the recognition test also increased not only for R items but also for F items, suggesting that participants did not stop processing F items after the F cue. Experiment 3 manipulated both the number of response/suppression attempts and the duration of response/suppression for each word pair during the response/suppression phase. The results showed that increasing the number of suppression attempts led to worse recall in the subsequent memory test. However, increasing the duration of suppression reduced the suppression effect. These results provide insights into a key factor for successful intentional forgetting and suppression.     

The role of extralist associations in false

The finding that new items are judged as remembered in the remember-know paradigm presents a challenge to traditional process and systems accounts of memory. In three experiments, we demonstrated that false remember responses can be caused by misattributing recollection to a context other than the study list. In Experiments 1 and 2, false remember responses to distractors that were unrelated to studied words increased if they were encountered in a “preexposure” phase a few minutes or even a few days prior to the studied list. A third experiment demonstrated that remember responses to preexposed distractors increased when they were encoded in a manner similar to studied items, despite the more similar items being of weaker overall memory strength. We propose a source misattribution account of false remembering to explain these data, suggesting that all remember judgments reflect conscious recollection of contextual details, but false remember judgments are partly the result of recollection of details from an extralist context (i.e., from a source other than the study list).     

The difference between implicit and explicit associative processes at study in creating false memory in the DRM paradigm

The effects of implicit and explicit associative processes for false recognition were examined by manipulating exposure duration of studied items; 20 ms or 2000 ms. Participants studied lists of words that were high associates to a nonpresented word (critical lure) in either condition. After learning each list, they took a recognition test and remember/know judgements immediately (Experiment 1) or 1 minute later (Experiment 2). In Experiment 1, know responses for critical lures were more in the 20 ms than in the 2000 ms conditions, while remember responses for them were more in the 2000 ms condition. Implicit associative processes create familiarity of critical lures, and explicit associative processes create details of false memories. Comparing the results of Experiment 1 with those of Experiment 2, remember responses for critical lures were increased with the prolonged time only in the 20 ms condition. Characteristics of false memory made by implicit associative processes could be changed by prolonged time.