The crucial role of postcue encoding in directed forgetting and context-dependent forgetting

People can intentionally forget previously studied material if, after study, a forget cue is provided and new material is learned. It has recently been suggested that such list-method directed forgetting arises because the forget cue induces a change in internal context and causes context-dependent forgetting of the studied material (L. Sahakyan & C. M. Kelley, 2002). The authors compared directed forgetting and context-dependent forgetting by examining whether, like a forget cue, a change in internal context needs subsequent learning of new material to be effective. Participants studied an item list and, after study, received a remember cue or a forget cue or their internal context was changed through an imagination task. In each condition, half the participants learned a second list, and the other half fulfilled an unrelated distractor task. Both the forget cue and the change in internal context induced forgetting of the first list only when learning of the second list was interpolated. These results suggest that postcue encoding of new material is crucial for both directed forgetting and (some forms of) context-dependent forgetting.     

合作学习情境下监控者监控发音任务中的定向遗忘效应

在以构建留学生的汉字语音库为共同目标的合作学习情境下,考察了合作学习中的监控者是否会表现出定向遗忘效应。实验一中,协助者朗读两字表的单字并接受定向遗忘或记忆字表中单字的指令;监控者监控发音的流畅性或准确性,并单独接受再认测验;实验二在协助者重新朗读单字的条件下监控者接受再认测验。结果发现:(1)实验一中,监控者只在深层监控发音准确性的任务时,再认成绩表现出定向遗忘效应,浅层监控发音流畅性的任务中未表现出定向遗忘效应;(2)实验二中在测验阶段复原学习情境后,深浅监控任务下的再认成绩虽存在显著差异,但定向遗忘效应也消失了。综合两个实验表明,合作学习情境下,非有意遗忘的监控者的定向遗忘效应与监控任务深度和学习情境复原与否存在密切联系。     

Context-dependent impairment of recollection in list-method directed forgetting

In list-method directed forgetting, people's ability to forget one of the sets of learned material is examined. Research shows that memory for to-be-forgotten items is impaired when assessed by a recall test and by recognition tests reliant on recollective processes. Retrieval inhibition and context-change mechanisms have been proposed to account for the directed forgetting effects and both of them account for the results obtained with recognition tests. However, the context change account makes a specific prediction that recollection is impaired by directed forgetting only if it makes use of contextual associations. In the present study, directed forgetting was examined with two types of recollection-based tasks making use of different types of associations, namely a list discrimination task utilising contextual associations and an associative recognition task utilising interitem associations. Consistent with the context change account, the costs of directed forgetting were observed in a list discrimination task and were not observed in an associative recognition task. The results indicate that impairment in recollection due to directed forgetting is not general and provide converging evidence to support the context-change account.     

定向遗忘条件下DRM词的加工深度和情境对错误记忆的影响*

在定向遗忘条件下探讨DRM词加工时产生的错误记忆现象,并探究造成这一现象的深层原因。实验一和实验二分别操纵了词的深、浅加工以及词所处的情境。实验一的结果发现只在深加工时,F指令下的DRM词受到抑制激活,低于R指令下的再认正确率,关键诱词的错误再认也与各指令下DRM词的恢复提取密切相关;实验二的结果发现集中情境和随机情境均会受到遗忘指令的影响抑制DRM词的正确再认,但集中情境下关键诱词的错误再认与各指令下DRM词的恢复提取关联更紧密。在定向遗忘条件下,用FTT理论解释实验一的结果较为合理,用AAT理论解释实验二的结果较为合理。     

The effects of context in item-based directed forgetting: Evidence for “one-shot” context storage

The effects of context on item-based directed forgetting were assessed. Study words were presented against different background pictures and were followed by a cue to remember (R) or forget (F) the target item. The effects of incidental and intentional encoding of context on recognition of the study words were examined in Experiments 1 and 2. Recognition memory for the picture contexts was assessed in Experiments 3a and 3b. Recognition was greater for R-cued compared to F-cued targets, demonstrating an effect of directed forgetting. In contrast, no directed forgetting effect was seen for the background pictures. An effect of context-dependent recognition was seen in Experiments 1 and 2, such that the hit rate and the false-alarm rate were greater for items tested in an old compared to a novel context. An effect of context-dependent discrimination was also observed in Experiment 2 as the hit rate was greater for targets shown in their same old study context compared to a different old context. The effects of context and directed forgetting did not interact. The results are consistent with Malmberg and Shiffrin’s (Journal of Experimental Psychology: Learning, Memory, and Cognition, 31, 322–336, 2005) “one-shot” context storage hypothesis that assumes that a fixed amount of context is stored in the first 1 to 2 s of the presentation of the study item. The effects of context are independent of item-based directed forgetting because context is encoded prior to the R or F cue, and the differential processing of target information that gives rise to the directed forgetting effect occurs after the cue.     

情绪一致性对有意遗忘的影响

有意遗忘是强调遗忘的有意性和指向性。对负性情绪的有意遗忘有利于个体的身心健康。本研究采用单字范式,实验一以正性、负性和中性情绪词为材料,探讨了情绪材料对有意遗忘的影响。结果发现,三类词语均表现出了显著的有意遗忘效应;实验二在实验一的基础上加入了情绪状态,探讨了情绪状态和情绪材料对有意遗忘的影响,结果发现,在积极情绪状态下,被试更多地遗忘负性情绪词;在消极情绪状态下,被试更多地遗忘中性词。表明个体对情绪信息的有意遗忘既受信息的情绪性影响,又受个体情绪状态的影响。     

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.     

Directed forgetting in older adults using the item and list methods

Four experiments investigated age-group differences in directed forgetting. Experiments 1A and 1B used the item method with recall (1A) and recognition (1B). Both of these experiments showed evidence of directed forgetting for both younger and older adults. The list method was used in Experiments 2A (recall) and 2B (recognition). For these experiments, there was directed forgetting when recall, but not recognition, was the dependent measure. Again, these results were found for younger and older adults. These results are discussed in terms of how different presentation types lead to the use of different theoretical mechanisms of directed forgetting (e.g., differential encoding, retrieval inhibition). Thus, it appears that both older and younger adults engage in adaptive memory strategies.     

Does an instruction to forget enhance memory for other presented items?

In an item-method directed forgetting paradigm, participants were required to attend to one of two colored words presented on opposite sides of a central fixation stimulus; they were instructed to Remember or Forget the attended item. On a subsequent recognition test, the Attended words showed a typical directed forgetting effect with better recognition of Remember words than Forget words. Our interest was in the fate of the Unattended words. When the study display disappeared before the memory instruction, there was no effect of that instruction on unattended words; when the study display remained visible during presentation of the memory instruction, there was a reverse directed forgetting effect with better recognition of unattended words from Forget trials than from Remember trials. Incidental encoding of task-irrelevant stimuli occurs following presentation of a Forget instruction - but only when those task-irrelevant stimuli are still visible in the external environment.     

Directed forgetting of negative performed actions is difficult: A behavioural study

Strong evidence suggests that both performing actions and emotional stimuli can enhance memory by capturing attention. However, the synergetic effect of the two factors on directed forgetting has not been assessed. In this study, we used an item-method directed forgetting paradigm to examine the forgetting of emotional materials depending on whether actions were performed. The results showed that action performance influenced the directed forgetting of emotional words. Specifically, when actions were performed there was a directed forgetting effect for neutral and positive words but not for negative words. In comparison, for verbal tasks, directed forgetting was observed for all words. The elaborative encoding prior to the remember/forget instructions and the influence of negative emotion on attentional inhibition after the presentation of the instructions together suggest that it is more difficult to intentionally forget negative performed actions.     

高低创造性思维水平者定向遗忘效应的差异研究

采用单字法定向遗忘范式,考察远距离联想任务得分高低者在中性和负性词语定向遗忘效应上的差异,来探讨创造性思维水平高低与主动抑制的关系。实验采用2(高/低创造性思维水平)×2(中性/负性词汇)×2(记住/忘记指令)×2(2s/5s时间间隔)混合设计,发现高低创造力组,在材料不同呈现时间下,对不同情绪材料的定向遗忘效应分别不同。低创者在2s和5s以及高创者在5s时间间隔时,均对中性词语表现出定向遗忘效应,而对负性词汇没有表现出明显的定性遗忘效应。高创者在2s时间间隔下,对中性和负性词语均表现出定向遗忘效应。结果表明较短时间内高创者对负性情绪的主动抑制能力优于低创者。     

The role of forget-cue salience in list-method directed forgetting

Research suggests that manipulating the wording of the forget cue in list-method directed forgetting affects the magnitude of directed forgetting both in younger children (Aslan, Staudigl, Samenieh, & Bauml, in press) and in older adults (Sahakyan, Delaney, & Goodmon, 2008). This occurs when the forget cue overemphasises the importance of forgetting in the current context. The present experiment investigated whether de-emphasising forgetting affected the magnitude of list-method directed forgetting in college adults. Some participants received overt forget cues that explicitly instructed them to forget earlier studied items, whereas others received covert forget cues that implied forgetting by emphasising selective remembering (e.g., "you will only need to remember some of the items"). Results indicated equivalent directed forgetting for both types of cues. However, regardless of the type of cue received, participants who reported using specific forgetting strategies in response to the forget cue showed directed forgetting, whereas those that reported doing nothing did not show any effects. The results underscore that successful directed forgetting requires engagement of controlled processes.     

The role of forget-cue salience in list-method directed forgetting

Research suggests that manipulating the wording of the forget cue in list-method directed forgetting affects the magnitude of directed forgetting both in younger children (Aslan, Staudigl, Samenieh, & Bauml, in press) and in older adults (Sahakyan, Delaney, & Goodmon, 2008). This occurs when the forget cue overemphasises the importance of forgetting in the current context. The present experiment investigated whether de-emphasising forgetting affected the magnitude of list-method directed forgetting in college adults. Some participants received overt forget cues that explicitly instructed them to forget earlier studied items, whereas others received covert forget cues that implied forgetting by emphasising selective remembering (e.g., “you will only need to remember some of the items”). Results indicated equivalent directed forgetting for both types of cues. However, regardless of the type of cue received, participants who reported using specific forgetting strategies in response to the forget cue showed directed forgetting, whereas those that reported doing nothing did not show any effects. The results underscore that successful directed forgetting requires engagement of controlled processes.     

负性情绪材料的定向遗忘及心理机制

采用项目法定向遗忘的研究范式,在两个实验中分别采用文字和图片材料考察了情绪性记忆定向遗忘的效果及其心理机制。实验中采用了中性和负性两种实验材料,设置了两种记忆指令出现时间（2秒后提示和5秒后提示）,相对于中性材料,被试更不容易忘记负性材料。记忆指令出现的时间只影响图片材料的定向遗忘。研究表明负性情绪会干扰定向遗忘,选择性编码理论可以解释情绪性文字材料的定向遗忘,而抑制理论更能解释情绪性图片材料的定向遗忘效应。     

短时记忆定向遗忘的负荷效应:来自ERP的证据

采用事件相关电位(ERPs)技术,通过一个短时记忆测试,考察记忆/遗忘线索在不同的工作记忆负荷条件下诱发的脑电差异。实验以字母和数字为刺激,要求被试记忆或遗忘不同数量的视觉信息。ERP结果发现:在线索呈现230~430ms的时间窗口,高负荷条件的遗忘线索比低负荷条件的遗忘线索诱发了更正的ERPs。这一结果表明,抑制机制在定向遗忘中有重要作用,抑制不同数量的信息需要不同数量的认知资源。     

Positive moods can eliminate intentional forgetting

People can intentionally forget previously studied information if, after study, a forget cue and new material to be encoded are provided. We examined how the affective state people experience during encoding of the new material modulates such directed forgetting. Positive, negative, and neutral moods were induced immediately before the new material was studied. The study materials themselves were neutral. The results showed sustained forgetting of the previously studied materials in negative moods but an elimination of the forgetting in positive moods. These findings agree with the effects of mood found for other cognitive tasks. They suggest that in positive moods, associative networks are activated, which leads to reactivation of List-1 items, and thus to elimination of the directed forgetting effects. These results contrast with recent reports on the role of emotional content in directed forgetting, which have described equivalent effects for neutral and emotional materials. Together, our findings suggest that directed forgetting is mainly affected by mood, and hardly at all by emotional content.     

Tag, you're it: Tagging as an alternative to yes/no recognition in item method directed forgetting

The current study contrasted a standard yes/no recognition task with a tagging recognition task in the context of an item-method directed forgetting paradigm. During the study phase, a series of words was presented one at a time, each followed by an instruction to remember (R) or forget (F). The retention of R and F study words was tested using either a typical yes/no recognition task or a tagging recognition task in which participants labeled each word as “R”, “F” or “New”. The directed forgetting effect observed in each task was equivalent in magnitude. However, the tagging recognition task afforded an additional analysis of the errors of misattribution that was not possible with the more typical yes/no recognition task. Interestingly, when falsely recognizing a Foil word, participants were more likely to assign an “F” tag than an “R” tag. These errors of misattribution are consistent with existing accounts of directed forgetting that suggest R words are better encoded than F words. We argue for the utility of the tagging procedure, given it does not alter the directed forgetting effect normally seen with yes/no recognition but provides additional information about errors of misattribution.     

Knowing what to remember and forget: A developmental study of cue memory in intentional forgetting

These experiments are the first to investigate children’s encoding and use of information about a memory cue in Bjork’s (1972) intentional forgetting task. In Experiment 1, children in Grades 2, 4, and 6 and college students were given cues to either remember or forget after the presentation of each picture. Recall and recognition tests of pictures and cues followed. The procedure in Experiment 2 was identical to that in Experiment 1 except that the list of presentation pictures was altered for some children (Grades 3 and 4) and adolescents (Grades 8 and 9) so that remember and forget cues were associated with particular taxonomic categories. In Experiment 3, the testing component was modified so that children (Grades 2, 3, and 4) and college students were asked to recall only the cue associated with each picture. The results indicated that (1) children as young as second graders encode the cue associated with each picture, although to a lesser extent than do college students, (2) much improvement in intentional forgetting is still occurring during adolescence, (3) only adults adequately cluster their recall by cue, (4) associating remember and forget cues with items from different categories does not increase the differentiation between cues, and (5) eliminating picture recall and recognition has minimal effects on the magnitude of cue judgments. These results suggest that children’s difficulties on intentional forgetting tasks stem, at least in part, from their poorer encoding of information about whether an item should be remembered or forgotten.     

Directed forgetting in direct and indirect tests of memory: Seeking evidence of retrieval inhibition using electrophysiological measures

We investigated whether directed forgetting as elicited by the item-cueing method results solely from differential rehearsal of to-be-remembered vs. to-be-forgotten words or, additionally, from inhibitory processes that actively impair retrieval of to-be-forgotten words. During study, participants (N = 24) were instructed to remember half of a series of presented words (TBR) and to forget the other half (TBF), as indicated by an instruction cue shown shortly after each word. During test, accuracy and reaction time measures from lexical decisions (indirect memory test) followed by recognition-memory judgements (direct memory test) were supplemented with event-related potential (ERP) recordings. Results from the behavioural measures revealed directed forgetting in the recognition-memory test but not the lexical-decision test. ERPs obtained during recognition indicated that TBR words elicited a larger parietal old/new effect than TBF words overall, suggesting that remember/forget instructions impaired conscious recollection processes more severely than familiarity processes. Moreover, TBF words that were successfully forgotten elicited less parietal activity than correctly rejected new words (the reversed old/new effect; Nowicka, A., Jednorórog, K., Wypych, M., & Marchewka, A. (2009). Reversed old/new effect for intentionally forgotten words: An ERP study of directed forgetting. International Journal of Psychophysiology, 71, 97–102). This was taken to implicate that inhibitory processes likely affected these items. Enhanced negativities for successfully forgotten TBF words relative to new words were observed in the lexical-decision task at early (150–250 ms) and late (800–1000 ms) time windows, suggesting that inhibitory influences disrupt more than just conscious recollection when memory retrieval is tested indirectly.     

越努力去忘就越能忘记吗？—情绪材料定向遗忘的"剂量效应"

采用项目法定向遗忘研究范式,在两个实验中分别使用情绪性语词和图片材料,考察主观努力程度影响情绪材料定向遗忘的心理机制。研究采用2(语词或图片情绪效价：正词/负词)×2（指示符：记住/忘记)×3（努力程度：20%/60%/100%）的被试内设计,因变量为情绪性语词或图片的再认率和定向遗忘效应。结果表明,正效价词在三种努力程度忘记条件的再认率无差别,而越努力去忘记负效价词,反而越能记住;正负效价的图片材料都呈现出越努力去忘记反而越能记住的特点。以上结果表明,语词与图片分别适合有意识加工和无意识加工,记住指令导致对情绪性语词和图片的选择性复述,符合选择性复述/被动衰退理论,而不同努力程度的忘记指令又引发了对情绪性语词和图片的主动抑制,符合注意抑制/执行控制理论。