What is the connection between true and false memories? The differential roles of interitem associations in recall and recognition.

Veridical memory for presented list words and false memory for nonpresented but related items were tested using the Deese/Roediger and McDermott paradigm. The strength and density of preexisting connections among the list words, and from the list words to the critical items, were manipulated. The likelihood of producing false memories in free recall varied with the strength of connections from the list words to the critical items but was inversely related to the density of the interconnections among the list words. In contrast, veridical recall of list words was positively related to the density of the interconnections. A final recognition test showed that both false and veridical memories were more likely when the list words were more densely interconnected. The results are discussed in terms of an associative model of memory, Processing Implicit and Explicit Representations (PIER 2) that describes the influence of implicitly activated preexisting information on memory performance.     

Creating False Memories of Words with or without Recognition of List Items: Evidence for Nonconscious Processes

Subjects exposed to lists of semantically related words falsely remember nonstudied words that are associated with the list items (e.g., Deese, 1959; Roediger & McDermott, 1995). To determine if subjects would demonstrate this false memory effect if they were unable to recognize the list items, we presented lists of semantically related words with or without a concurrent memory load at rates of 2 s, 250 ms, or 20 ms per word (Experiment 1, between-subjects design) and 2 s or 20 ms per word (Experiment 2, within-subjects design). We found that the subjects falsely recognized semantically related nonstudied words in all conditions, even when they were unable to discriminate studied words from unrelated nonstudied words. Recognition of list items was unnecessary for the occurrence of the false memory effect. This finding suggests that this memory illusion can be based on the nonconscious activation of semantic concepts during list presentation.     

False memory across languages: implicit associative response vs fuzzy trace views

We investigated false recognition across languages using the Deese-Roediger-McDermott (DRM) paradigm. A group of English-French bilinguals studied lists of converging associates, some lists in English and some in French, and then performed a recognition test containing studied list items and nonstudied critical lures whose language matched or mismatched the language at study. Participants were instructed to answer old only if the test cue was in the same language as the studied word. The results yielded a robust false memory rate both within-language and across-languages. The effect of the study-test language shift was much larger for list items than for critical lures. This finding suggests that memory representations for critical lures contain primarily semantic gist traces and little surface information, and hence is more consistent with the fuzzy trace view than with the implicit associative response view. In sum, the study demonstrates the existence of false memory across languages, and provides information about the memory traces underlying veridical and illusory recognition.     

Categorical <Emphasis Type="Italic">and</Emphasis> associative relations increase false memory relative to purely associative relations

The goal of the present study was to examine the contributions of associative strength and similarity in terms of shared features to the production of false memories in the Deese/Roediger–McDermott list-learning paradigm. Whereas the activation/monitoring account suggests that false memories are driven by automatic associative activation from list items to nonpresented lures, combined with errors in source monitoring, other accounts (e.g., fuzzy trace theory, global-matching models) emphasize the importance of semantic-level similarity, and thus predict that shared features between list and lure items will increase false memory. Participants studied lists of nine items related to a nonpresented lure. Half of the lists consisted of items that were associated but did not share features with the lure, and the other half included items that were equally associated but also shared features with the lure (in many cases, these were taxonomically related items). The two types of lists were carefully matched in terms of a variety of lexical and semantic factors, and the same lures were used across list types. In two experiments, false recognition of the critical lures was greater following the study of lists that shared features with the critical lure, suggesting that similarity at a categorical or taxonomic level contributes to false memory above and beyond associative strength. We refer to this phenomenon as a “feature boost” that reflects additive effects of shared meaning and association strength and is generally consistent with accounts of false memory that have emphasized thematic or feature-level similarity among studied and nonstudied representations.     

Inadvertent plagiarism in young and older adults: The role of working memory capacity in reducing memory errors

Two experiments examined inadvertent plagiarism in young and older adults. Young and older adults took turns generating category exemplars in small groups, and after a short retention interval recall was tested and subjects were asked to generate new exemplars (i.e., exemplars not initially generated). When asked to generate new exemplars, older adults were more likely to repeat exemplars that had been generated earlier by others (i.e., generate-new plagiarism). When asked to recall the exemplars they had generated earlier, older adults were more likely to claim that they had generated exemplars that had been generated by others (i.e., recall-own plagiarism), and were also more likely to falsely recall exemplars that had not been generated at all. There were no age differences in confidence for items that were plagiarized on the generate-new task. Hierarchical regression analyses indicated that age differences in generate-new plagiarism and false recall were entirely mediated by measures of episodic recall and working memory capacity. We conclude that inadvertent plagiarism errors result from the failure of systematic decision processes, and that controlled attention is important for avoiding memory errors.     

The role of associative strength in children's false memory illusions

The effects of associative strength on rates of 7- and 11-year-old children's true and false memories were examined when category and Deese-Roediger-McDermott (DRM) lists were used to cue the same critical lure. Backward associative strength (BAS) was varied such that the category and DRM lists had the same strength (DRM=category), DRM lists had more BAS (DRM>category), or category lists had more BAS (DRM<category). If BAS drives children's false memories then BAS, not the type of relation across items in a list, should determine false memory production. The results confirmed this prediction using both recall and recognition measures: (1) both true and false memories increased with age, (2) true memory was better for category than DRM lists but there were no differences for false memory, and (3) at all ages, false memories varied predictably with changes in BAS but were unaffected by list-type manipulations. These findings are discussed in the context of models of false memory development.     

Older adults encode--but do not always use--perceptual details: intentional versus unintentional effects of detail on memory judgments

Investigations of memory deficits in older individuals have concentrated on their increased likelihood of forgetting events or details of events that were actually encountered (errors of omission). However, mounting evidence demonstrates that normal cognitive aging also is associated with an increased propensity for errors of commission-shown in false alarms or false recognition. The present study examined the origins of this age difference. Older and younger adults each performed three types of memory tasks in which details of encountered items might influence performance. Although older adults showed greater false recognition of related lures on a standard (identical) old/new episodic recognition task, older and younger adults showed parallel effects of detail on repetition priming and meaning-based episodic recognition (decreased priming and decreased meaning-based recognition for different relative to same exemplars). The results suggest that the older adults encoded details but used them less effectively than the younger adults in the recognition context requiring their deliberate, controlled use.     

汉字字形关联对错误记忆的影响

采用DRM范式,研究汉字字形关联对错误记忆的影响。实验以占汉字主体的形声字为材料。学习阶段使用了两类字表:在一半字表中,各字表内汉字及相应的关键诱饵具有相同形旁;另一半字表中,各字表内汉字及相应关键诱饵具有相同声旁。再认测试中,被试对两类关键诱饵均表现出了明显的错误记忆,并且其效应大小与字表汉字相似度成正比。这些结果说明,汉字的字形关联可以诱发错误记忆现象,并且这种错误记忆效应由汉字间字形相似度决定。     

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).     

Interference processes in monkey auditory list memory

A rhesus monkey’s memory was tested for single items and four-item lists of natural and environmental sounds. Memory items were presented from a center speaker, followed by a retention delay and then a choice response to a test sound presented simultaneously from two side speakers. Recognition of the last item of four-item lists was much poorer than that of single items at 0-, 1-, and 2-sec delays, despite there being the same temporal relations between study and test. This result showed that the first three items proactively interfered with memory of the last list item. Proactive interference dissipated after 2 sec, revealing a recency effect that eventually equaled single-item performance. Recognition of the first item of four-item lists was much poorer than single items at 20- and 30-sec delays, showing that the last three items retroactively interfered with memory of the first list item. The results point to the critical nature of interference processes in the understanding of serial position functions.     

The influence of age on memory for distinctive events

We examined whether memory for distinctive events is influenced by aging. To do so, we used a semantic isolation paradigm in which people show superior memory for a word when it is presented in a list of items from a different semantic category (e.g., the word table is presented in a list of all bird exemplars) as compared with when the same word (table) is presented in a list of unrelated words. Results showed that both younger and older adults demonstrated an isolation effect in memory, although older adults showed a numerically smaller isolation effect than did younger adults. Results suggest that in contrast with previous findings (Cimbalo & Brink, 1982), older adults can take advantage of this type of distinctiveness to aid memory performance.     

强大的错误记忆效应:词表呈现时间与呈现方式的影响

本研究采用DRM范式(Deese-Roediger-McDermott paradigm),考察了词表项目的呈现时间与呈现方式对错误记忆效应的影响。结果发现,被试对关键诱饵的错误再认受到学习阶段词表项目的呈现方式的影响,表现为所有项目随机呈现条件下的错误再认明显低于分组呈现条件,尤其是在20ms的随机呈现条件下,观察到了对关键诱饵的最低错误再认率。说明在对词表项目的编码阶段产生了对关键诱饵的连续激活,而对关键诱饵的错误记忆则是基于连续激活的不断累积的结果,当词表项目的随机呈现阻断了连续激活过程时,便会有效降低错误记忆效应。而且,在所有实验条件下均发现了错误记忆效应产生中所伴随的强烈主观体验,证实了错误记忆是一种强大的效应。     

Effects of Presentation Format and List Length on Children's False Memories

The effect of list length on children's false memories was investigated using list and story versions of the Deese/Roediger-McDermott procedure. Short (7 items) and long (14 items) sequences of semantic associates were presented to children aged 6, 8, and 10 years old either in lists or embedded within a story that emphasized the list theme. Subsequent tests of recognition memory revealed different effects of length for lists and stories across development. Longer lists produced more false alarms to critical lures for 8- and 10-year-olds only, and longer stories produced more false alarms to critical lures for 6-year-olds only. These results demonstrate that increasing the number of items presented at study increases false recognition for younger as well as older children when the theme of the items is made salient.     

提取抑制对错误记忆的影响

该研究探讨提取抑制能否减少错误记忆的发生.以自编的DRM词表为实验材料,实验1采用有意遗忘范式（有意抑制）,实验2采用部分线索效应范式（无意抑制）.实验1结果发现：关键诱饵在“记住”条件下的错误回忆成绩显著高于“遗忘”条件下的错误回忆成绩;学过项目在“记住”条件下的正确回忆成绩显著高于“遗忘”条件下的正确回忆成绩.实验2结果发现：关键诱饵在“无部分线索”条件下的错误回忆成绩显著高于“部分线索”条件下的错误回忆成绩;学过项目在“无部分线索”条件下的正确回忆成绩显著高于“部分线索”条件下的正确回忆成绩.研究结果提示：有意和无意两种提取抑制都可以降低错误记忆,结果支持基于激活与监测的双加工理论的观点.     

项目特异性加工和关系加工对非熟练中-英双语者跨语言错误记忆的影响

采用DRM范式进行跨语言错误记忆的研究较为鲜见, 而且得出了许多不同的结果, 关于错误记忆跨语言产生的理论解释也是各执己见。研究以非熟练中-英双语大学生为被试, 采用DRM范式对非熟练中-英双语者的跨语言错误记忆进行了研究。在2个实验中, 分别探讨了项目特异性加工和关系加工条件下, 语义激活的不同水平对跨语言错误记忆的影响。结果发现：1)非熟练中-英双语者也存在跨语言的错误记忆; 2)在项目特异性加工和关系加工条件下, 相同语言内与不同语言间发生关键诱词的错误再认的结果是不同的; 3)只在项目特异性加工条件下, 长词表比短词表会诱发更多的对关键诱词的错误再认。研究结果支持了激活-监测理论。     

Influence of cognitive abilities and age on word recall performance across trials and list segments

The influence of cognitive abilities and age on multitrial word recall performance was examined for different list segments (i.e., first, middle, and last) and across trials by having 2497 participants ages 18-98 complete a multitrial word list test along with reference cognitive ability tests. As expected, higher episodic memory ability was associated with better recall on all list segments but with a smaller influence for the last items on the early trials. Performance improved across trials, but there were no relations of the fluid intelligence construct that might be postulated to be associated with effective strategy implementation with any of the recall measures. Advanced age was associated with lower levels of performance, but very few of the age relations were significant after the variation in the reference cognitive abilities was controlled for.     

Memory search: When does semantic analysis occur?

This study was addressed to the determination of the stage at which semantic analysis occurs during a STM recognition task. A list of exemplars (memory set), drawn from 13 different categories, was presented at a rate of 11/2 sec/item, followed by a category name probe. Ss then indicated whether any of the exemplars in the memory set belonged to that category. List length was varied from 5 to 7, with each memory set containing items from either two or three categories. It was found that RT was independent of list length, but did increase by 60 msec as the number of categories represented in the list increased from two to three. From this, it was concluded that activation of a superordinate category representation occurred upon presentation of each memory-set item, and that the memory scan was done on these superordinate categories.     

The breadth of memory search

The recall of previously studied items is widely believed to incorporate a search of a markedly constrained set of possibilities, and the present study examines whether this set of items typically includes unstudied semantic associates of the study items. In an episodic task, participants recalled a previously studied list of eight exemplars drawn from a small or large category, and, in a semantic task, participants generated exemplars from these categories. Category size affected the time course of recall in the semantic task but not in the episodic task. This empirical dissociation between episodic and semantic memory is consistent with the view that episodic memory search efficiently excludes unstudied semantic associates of the study items and is instead constrained to those items sharing the temporal and spatial attributes of the episode.     

Paradoxical effects of presentation modality on false memory.

Two experiments are reported in which the effects of presentation modality on false memory in recall and recognition are studied. False recall and recognition of critical targets are lower for non-presented items related to a study list when that study list is presented visually than when presented auditorily. This pattern of low levels of false memory for critical targets holds even when participants read the visually presented study items aloud. These results suggest that recollection of visual detail plays a role in the prevention of false memory. However, both the hit rates (true memory) and the false-alarm rates to weakly related distractors (non-critical targets) were higher for visual presentation than for auditory presentation, suggesting that more than one mechanism may underlie false recognition.     

Using story contexts to bias children’s true and false memories

The effects of embedding standard Deese/Roediger-McDermott (DRM) lists into stories whose context biased interpretation either toward or away from the overall themes of the DRM lists on both true and false recognition were investigated with 7- and 11-year-olds. These biased story contexts were compared with the same children’s susceptibility to false memory illusions using the standard DRM list presentation paradigm. The results showed the usual age effects for true and false memories in the standard DRM list paradigm, where 11-year-olds exhibited higher rates of both true and false recognition compared with the 7-year-olds. Importantly, when DRM lists were embedded in stories, these age effects disappeared for true recognition. For false recognition, although developmental differences were attenuated, older children were still more susceptible to false memory illusions than younger children. These findings are discussed in terms of current theories of children’s false memories as well as the role of themes and elaboration in children’s memory development.