表象加工水平对错误记忆的影响

从表象加工水平角度考察引发错误记忆的因素。结果发现,深的表象加工水平能够抑制诱饵词产生较大的激活,减少错误记忆的发生。随着表象加工水平的加深,有意表象的错误记忆效应显著低于无意表象,而正确记忆效应则显著高于无意表象,表明表象加工水平对错误记忆具有重要影响。根据研究结果提出表象激活混淆假设,认为人们虽然可以用表象作为信息表征的方式,却无法直接获取与之联系的激活路径。当人们推测表象激活的来源时,容易混淆表象激活的来源,产生错误记忆。     

表象编码方式影响错误记忆的研究

考察表象编码方式对错误记忆的影响。结果发现,与整合表象编码比,个别表象编码能够促进项目的特异性加工,使项目更有区分性,阻止(或减弱)诱饵词的内隐表象激活,有利于个体获取表象的激活路径,减少错误记忆发生,说明表象编码方式对错误记忆具有重要影响。根据研究结果提出表象激活混淆假设,认为个体虽然可以使用表象作为信息表征方式,却无法直接获取与之联系的激活路径。当个体推测表象激活的来源时,容易混淆表象激活的来源,错误记忆就发生了。表象激活混淆假设为视觉表象引发错误记忆的心理机制提供了说明。     

表象激活混淆与错误记忆的关系——来自ERP研究的证据

采用ERP技术考察表象激活混淆与错误记忆的关系。发现:(1)在编码阶段,随后错误记忆的ERPs比随后正确记忆的ERPs在顶区、枕区和颞枕区有更大的晚正成分。(2)在提取阶段,错误记忆的ERPs比正确记忆的ERPs在顶区、枕区和颞枕区有更大的晚正成分。整个研究表明,表象激活混淆在错误记忆产生中具有重要作用。根据研究结果提出"表象激活混淆假设",认为人们虽然使用表象的信息表征方式,却无法获取与之联系的激活路径,容易混淆表象激活的来源。表象激活混淆是表象引发错误记忆的机制。     

激活水平和呈现方式对错误记忆的影响

随机抽取80名大学生参与实验,采用DRM(Deese-Roediger-Mcdermott)范式,探讨了激活水平和呈现方式对错误记忆的影响。结果发现:(1)在随机呈现条件下,关键诱饵的错误再认率显著低于分组呈现条件,但学过项目的正确再认率在两种条件下无差异。(2)在高激活水平条件下,学过项目的正确再认率明显低于低激活水平条件,但关键诱饵的错误再认率在两种激活条件下的差异不够明显。这表明,呈现方式对关键诱饵的错误再认率有显著影响,而激活水平的影响则不显著。由此可知,人们的记忆可以在没有任何外界信息干扰的情况下因内在联想过程而自发地发生改变。     

高低字频对汉字记忆中错误联接的影响

通过实验考察高低字频对汉字记忆中错误联接的影响.实验表明,汉字再认记忆中出现了频率的镜子效应,但在反应时间限制下,镜子效应中对学习词的正确再认率的差异消失.被试对低频联合诱字的错误再认率高于高频联合诱字.无论是高频字还是低频字,被试对联合诱字的反应时都长于对学习字和无关字的反应时.研究结果可用修正后的激活混淆来源理论(source of activation confusion,SAC)解释.     

加工水平和呈现时间对错误记忆的影响

在DRM范式下,通过操纵加工水平和呈现时间,考察它们对错误记忆和真实记忆的影响.结果发现,加工水平对错误记忆没有影响,随着对词表加工水平的提高,错误再认率差异不显著.而加工水平对正确记忆有显著影响,不同加工水平间的正确再认率差异极其显著.错误记忆与正确记忆在加工水平上表现出了分离.在较慢呈现时间下,呈现时间对错误记忆和正确记忆的影响均不显著.     

汉字记忆中错误联接的码相加效应

采用错误联接的实验范式考察汉字记忆中的码相加效应。实验1采用形码加义码,结果发现对义似形似组的特征诱字错误再认率显著高于义异形似组的。实验2采用形码加音码．结果发现对音似形似组的诱字的错误再认率显著高于音异形似组的。研究表明汉语记忆中的错误联接存在码相加效应。研究结果可用激活混淆来源理论解释。     

启动情绪和呈现方式对错误记忆的影响

采用DRM范式(Deese-Roediger-Mc Dermott paradigm),考察了启动情绪状态下词表项目的呈现方式对错误记忆的影响。结果发现:(1)启动情绪主效应不显著。(2)词表项目的呈现方式主效应显著。(3)启动情绪与呈现方式间存在交互作用。在愉快启动情绪状态下分组呈现的错误再认率明显高于随机呈现条件;当词表项目分组呈现时,三种情绪状态下的错误再认率有显著差异,其中愉快启动情绪下的错误再认率最高,其次是悲伤情绪,最低的为对照组—非启动情绪状态。说明启动的愉快情绪增强了对关键诱饵的连续激活累积效应,从而导致对关键诱饵较高的错误再认率。     

自尊和同伴压力对关联性错误记忆的影响

目的:探索不同自尊水平的初中生在无同伴压力或有同伴压力下完成记忆任务时,产生的关联性错误记忆情况.方法:使用自尊量表(SES)从78名中学生中挑出高自尊和低自尊学生42人,采用错误记忆研究的DRM范式,探讨自尊、同伴压力对关联性错误记忆的影响.结论:(1)关键诱饵的错误再认率高于有关项目和无关项目,有关项目的错误再认率高于无关项目；(2)自尊和同伴压力对关联性错误记忆会产生影响,高自尊和低自尊被试在有无同伴压力条件下对三种未学习词的错误再认率有所不同；在有同伴压力条件下,三种未学习词的错误再认率在高自尊被试和低自尊被试间都不存在显著差异,产生了记忆一致性效应.     

儿童句子错误记忆:发展性逆转现象及精加工推理效应

为探究文本背景下句子错误记忆的发展性逆转现象及精加工推理效应,95名有效被试学习3篇文本材料后,参与由学过句、内涵推理句、外延推理句和无关句组成的再认测验。结果发现：（1）高中二年级被试学过句的正确再认率和关键诱饵句的校正的错误再认率均显著高于小学五年级和初中二年级,后二者差异不显著;（2）内涵推理句错误再认率高于外延推理句,高中二年级被试尤甚。结论：（1）句子真实记忆随着年龄增长而增加;句子错误记忆存在发展性逆转现象,初中二年级到高中二年级是句子错误记忆发展相对迅速的阶段;（2）文本背景下,不同的精加工推理诱发了不同程度的句子错误记忆,这种精加工推理效应与一般世界知识的自上而下激活的程度有关。     

Source memory for unrecognized items: Predictions from multivariate signal detection theory

We report three experiments investigating source memory for words that were called "new" on a recognition test. In each experiment, participants could accurately specify the source of words that they failed to recognize. Results also demonstrated that source memory for unrecognized items varied with the bias to respond "old" in recognition decisions: Participants displayed unrecognized source memory when they were told that 25% of the recognition test words were old (promoting conservative responding) but not when they were told that 75% of the test words were old (promoting liberal responding). Our results were successfully predicted by a multivariate signal detection approach to recognition/source memory.     

Imagery encoding effects on memory in the DRM paradigm: A test of competing predictions

In three experiments the effects of imagery encoding and test format on false memory rates in the Deese–Roediger–McDermott (DRM) paradigm were examined. After generating images of individual items (Experiment 1) or integrated subsets (Experiment 2), all of which were embedded in thematically related lists, participants were surprised by a recognition memory test or one of three kinds of source tests. As predicted by a distinctive encoding hypothesis, generating individual images led to better accuracy on presented items, and better monitoring of critical lures, than generating integrated images (Experiments 1 and 2). However, both kinds of imagery encoding led to fewer endorsements of critical lures compared to a non‐imagery encoding condition (Experiment 3). Imagery encoding effects were also independent of test format. The implications of these findings for the use of DRM‐false memory rates in debates about the use of guided imagery techniques are discussed. Copyright © 2008 John Wiley & Sons, Ltd.     

Associative false recognition occurs without strategic criterion shifts

In the DRM (Deese/Roediger and McDermott) false memory paradigm, subjects studied lists of words associated with nonpresented critical words. They were tested in one of four instructional conditions. In a standard condition, subjects were not warned about the DRM Effect. In three other conditions, they were told to avoid false recognition of critical words. One group was warned before study of the lists (affecting encoding and retrieval processes), and two groups were warned after study (affecting only retrieval processes). Replicating prior work, the warning before study considerably reduced false recognition. The warning after study also reduced false recognition, but only when critical items had never been studied; when critical items were studied in half the lists so that subjects had to monitor memory for their presence or absence, the warning after study had little effect on false recognition. Because warned subjects were trying to avoid false recognition, the high levels of false recognition in the latter condition cannot be due to strategically guessing that critical test items were studied. False memories in the DRM paradigm are not caused by such liberal criterion shifts.     

Reduced effects of pictorial distinctiveness on false memory following dynamic visual noise

High levels of false recognition for non-presented items typically occur following exposure to lists of associated words. These false recognition effects can be reduced by making the studied items more distinctive by the presentation of pictures during encoding. One explanation of this is that during recognition, participants expect or attempt to retrieve distinctive pictorial information in order to evaluate the study status of the test item. If this involves the retrieval and use of visual imagery, then interfering with imagery processing should reduce the effectiveness of pictorial information in false memory reduction. In the current experiment, visual-imagery processing was disrupted at retrieval by the use of dynamic visual noise (DVN). It was found that effects of DVN dissociated true from false memory. Memory for studied words was not influenced by the presence of an interfering noise field. However, false memory was increased and the effects of picture-induced distinctiveness was eliminated. DVN also increased false recollection and remember responses to unstudied items.     

The effect of presentation format and encoding strategy on associative memory distortion

IntroductionPrevious studies using semantically related words revealed more accurate memory when the items were encoded visually rather than auditorily and when mental images were created during encoding. However, how the level of memory distortion is affected by the creation of different mental imagery formats or by techniques that should suppress generation of mental images has rarely been investigated.ObjectiveThe aim of the present studies was to investigate the ways in which the encoding strategy affects the accuracy of memory reports for two presentation formats of semantically related words: verbal and pictorial.MethodIn experiment 1, the participants were asked to memorize either pictures or their verbal equivalents (words) from the same category, using one of two encoding strategies: uttering the words or counting backwards. In experiment 2, pictorially or auditory presented material was encoded together with the creation of either visual or auditory mental images of the items. The results of the experimental groups were compared to control groups that received no specific instruction.ResultsHigher levels of false recognition, together with lower rates of correct recognition, were observed for words, presented either visually or auditory, relative to pictures. Moreover, self-generation of additional code during the processing of information favored the reduction of false recognitions.ConclusionEncoding strategies that engaged dual coding reduced false recognition. The results are discussed within the distinctiveness heuristic phenomenon.     

Test-induced priming of false memories

Of interest was whether prior testing of related words primes false memories in the Deese/Roediger-McDermott (DRM) paradigm. After studying lists of related words, subjects made old-new judgments about zero, three, or six related items before being tested on critical nonpresented lures. When the recognition test was self-paced, prior testing of list items led to faster false recognition judgments, but did not increase the rate of false alarms to lures from studied lists. Critically, this pattern changed when decision making at test was speeded. When forced to respond quickly—presumably precluding the use of monitoring processes—clear test-induced priming effects were observed in the rate of false memories. The results are consistent with an activation-monitoring explanation of false memories and support that retrieving veridical memories can be a source of memory error.     

Getting at the source of distinctive encoding effects in the DRM paradigm: evidence from signal-detection measures and source judgments

Studying Deese–Roediger–McDermott (DRM) lists using a distinctive encoding task can reduce the DRM false memory illusion. Reductions for both distinctively encoded lists and non-distinctively encoded lists in a within-group design have been ascribed to use of a distinctiveness heuristic by which participants monitor their memories at test for distinctive-task details. Alternatively, participants might simply set a more conservative response criterion, which would be exceeded by distinctive list items more often than all other test items, including the critical non-studied items. To evaluate these alternatives, we compared a within-group who studied 5 lists by reading, 5 by anagram generation, and 5 by imagery, relative to a control group who studied all 15 lists by reading. Generation and imagery improved recognition accuracy by impairing relational encoding, but the within group did not show greater memory monitoring at test relative to the read control group. Critically, the within group’s pattern of list-based source judgments provided new evidence that participants successfully monitored for distinctive-task details at test. Thus, source judgments revealed evidence of qualitative, recollection-based monitoring in the within group, to which our quantitative signal-detection measure of monitoring was blind.     

Modality effect in false recognition: evidence from Chinese characters

Using the Deese/Roediger‐McDermott (DRM) false memory method, Smith and Hunt ( 1998 ) first reported the modality effect on false memory and showed that false recall from DRM lists was lower following visual study than following auditory study, which led to numerous studies on the mechanism of modality effect on false memory and provided many competing explanations. In the present experiment, the authors tested the modality effect in false recognition by using a blocked presentation condition and a random presentation condition. The present experiment found a modality effect different from the results of the previous research; namely, false recognition was shown to be greater following visual study than following auditory study, especially in the blocked presentation condition rather than in the random presentation condition. The authors argued that this reversed modality effect may be due to different encoding and processing characteristics between Chinese characters and English words. Compared with English words, visual graphemes of critical lures in Chinese lists are likely to be activated and encoded in participants' minds, thus it is more difficult for participants to discriminate later inner graphemes from those items presented in visual modality. Hence visual presentation could lead to more false recognition than auditory presentation in Chinese lists. The results in the present experiment demonstrated that semantic activation occurring during the encoding and retrieve phases played an important role in modality effect in false recognition, and our findings might be explained by the activation‐monitoring account.     

Generation and mnemonic encoding induce a mirror effect in the DRM paradigm

Encoding tasks that increase memory accuracy are appealing from both practical and theoretical perspectives. Within the Deese/Roediger-McDermott (DRM) paradigm, we found that generating list words from anagrams (relative to reading) produced a mirror effect: enhanced recognition of studied words coupled with a reduction in false recognition. Signal detection analyses suggest that the increase in correct recognition was due to enhanced item-specific encoding of the list words, whereas the reduction in false recognition was due to enhanced strategic monitoring at test (i.e., a distinctiveness heuristic), rather than to reduced relational encoding at study. Further support for a distinctiveness heuristic account was obtained using both "theme judgment" instructions and within-group conditions. In our final experiment, we replicated this mirror effect using a purely mnemonic (self-referential) encoding task, showing that extra perceptual cues are not necessary to induce participants to adopt a successful memory-improvement strategy at test.     

Encoding strategy affects false recall and recognition: Evidence from categorical study material

The present research investigated memory vulnerability to distortions. Different encoding strategies were used when categorized lists were studied. The authors assumed that an imagery strategy would be responsible for decreasing false memories more than a word-whispering strategy, which is consistent with the model of semantic access and previous research in the Deese-Roediger-McDermott paradigm (the DRM paradigm; Deese, 1959; Roediger & McDermott, 1995). A normative study of category lists and 4 experiments were conducted to verify the memory vulnerability to different encoding strategies (imagery, word-whispering, control). Half of subjects recalled and half recognized previously studied words. The results revealed a marked reduction in false recognition and recall after imagery encoding, relative to after word-whispering encoding.