Are the memories of older adults positively biased?

There is disagreement in the literature about whether a "positivity effect" in memory performance exists in older adults. To assess the generalizability of the effect, the authors examined memory for autobiographical, picture, and word information in a group of younger (17-29 years old) and older (60-84 years old) adults. For the autobiographical memory task, the authors asked participants to produce 4 positive, 4 negative, and 4 neutral recent autobiographical memories and to recall these a week later. For the picture and word tasks, participants studied photos or words of different valences (positive, negative, neutral) and later remembered them on a free-recall test. The authors found significant correlations in memory performance, across task material, for recall of both positive and neutral valence autobiographical events, pictures, and words. When the authors examined accurate memories, they failed to find consistent evidence, across the different types of material, of a positivity effect in either age group. However, the false memory findings offer more consistent support for a positivity effect in older adults. During recall of all 3 types of material, older participants recalled more false positive than false negative memories.     

The influence of theme identifiability

In the present study, we used the Deese/Roediger-McDermott paradigm to analyze the relationship between theme identifiability of word lists and false memories in adults and children. We conducted two normative studies to determine the identifiability levels for critical unpresented words in 40 associative lists in adults and in 16 associative lists in children. Then, in three experiments, false memories for critical words that were either easy or hard to identify were analyzed in adults and in children 4–5 years old and 11–12 years old. Opposite results were found for adults and children. Lists with highly identifiable critical words produced fewer false memories for adults but more false memories for children. These results suggest that, if they can identify critical words, adults use an identify-to-reject strategy to edit out false memories, whereas, in children, theme identification does not lead to the use of such a monitoring strategy.     

Attempting to avoid false memories in the Deese/Roediger—McDermott paradigm: Assessing the combined influence of practice and warnings in young and old adults

On each of five study-test trials, young and old adults attempted to memorize the same list of 60 words (e.g., bed, rest, awake), which were blocked according to their convergence on four corresponding associates. Half of the participants in each age group were given an explicit warning about the DRM paradigm prior to encoding and were asked to attempt to avoid recalling any associated but nonpresented words (e.g., sleep). Lists were presented auditorily at either a fast (1,250 msec/word) or a slow (2,500 msec/word) rate. Without a warning, the probability of veridical recall across trials increased for both age groups; however, the probability of false recall across trials decreased only for young adults. When a warning about false recall was provided, young adults virtually eliminated false recall by the second trial. Even though old adults also used warnings to reduce false recall on Trial 1, they were still unable to decrease false memories across the remaining four study-test trials. Old adults also reduced false recall more with slow than with fast presentation rates. Taken together, these findings suggest that old adults have a breakdown in spontaneous, self-initiated source monitoring as reflected by little change in false recall across study-test trials but a preserved ability to use experimenter-provided warnings or slow presentation rates to reduce false memories.     

老年人与青年人阅读空格文本的注视位置效应

采用EyeLink2000眼动仪,以14名老年人和14名青年人为被试,探讨他们阅读空格汉语文本的注视位置效应.阅读材料分为正常无空格文本和词间空格文本两种.结果发现:(1)在阅读词间空格文本和正常无空格文本时,老年人与青年人都表现出单次注视的首次注视是位于词的中心,多次注视的首次注视是位于词的开头;(2)老年人阅读正常无空格文本时对词尾的注视概率显著低于词间空格文本,而青年人则没有差异.结果表明老年人与青年人在阅读空格文本时存在注视位置效应.     

Providing information about diagnostic features at retrieval reduces false recognition

In the following study, participants encoded blocked DRM word lists and we varied whether they received information before test about the utility of mnemonic features that potentially discriminate between veridical and false memories. The results of three experiments revealed that this manipulation successfully reduced false recognition of critical theme words. We also found that this manipulation was effective for younger but not older adults. Furthermore, calling attention to the features in test instructions alone was sufficient for reducing false recognition and its effectiveness was not enhanced by also asking participants to rate their phenomenal experience. We argue that providing diagnostic information before test allows participants to establish more accurate expectations about the task and thus improves the efficacy of retrieval and monitoring processes that are subsequently engaged.     

Providing information about diagnostic features at retrieval reduces false recognition

In the following study, participants encoded blocked DRM word lists and we varied whether they received information before test about the utility of mnemonic features that potentially discriminate between veridical and false memories. The results of three experiments revealed that this manipulation successfully reduced false recognition of critical theme words. We also found that this manipulation was effective for younger but not older adults. Furthermore, calling attention to the features in test instructions alone was sufficient for reducing false recognition and its effectiveness was not enhanced by also asking participants to rate their phenomenal experience. We argue that providing diagnostic information before test allows participants to establish more accurate expectations about the task and thus improves the efficacy of retrieval and monitoring processes that are subsequently engaged.     

The effect of warnings on false memories in young and older adults

In the present experiments, we examined adult age differences in the ability to suppress false memories, using the Deese-Roediger-McDermott (DRM) paradigm (Deese, 1959; Roediger & McDermott, 1995). Participants studied lists of words (e.g., bed, rest, awake, etc.), each related to a nonpresented critical lure word (e.g., sleep). Typically, recognition tests reveal false alarms to critical lures at rates comparable to those for hits for studied words. In two experiments, separate groups of young and older adults were unwarned about the false memory effect, warned before studying the lists, or warned after study and before test. Lists were presented at either a slow rate (4 sec/word) or a faster rate (2 sec/word). Young adults were better able to discriminate between studied words and critical lures when warned about the DRM effect either before study or after study but before retrieval, and their performance improved with a slower presentation rate. Older adults were able to discriminate between studied words and critical lures when given warnings before study, but not when given warnings after study but before retrieval. Performance on a working memory capacity measure predicted false recognition following study and retrieval warnings. The results suggest that effective use of warnings to reduce false memories is contingent on the quality and type of encoded information, as well as on whether that information is accessed at retrieval. Furthermore, discriminating between similar sources of activation is dependent on working memory capacity, which declines with advancing age.     

老年人汉语阅读中预测误差成本的产生机制

阅读的认知加工机制随年龄变老只发生了量变还是也产生了质变, 是毕生发展研究领域的重要问题。要进行有效的语言处理, 读者必须结合已有的经验知识和当前语境对即将出现的信息进行预测加工。因此, 要解决上述问题就要回答老年人阅读中预测加工机制发生了怎样变化, 即预测误差成本是如何产生的。研究拟采用眼动脑电同步记录技术, 在自然阅读过程中实时获取语言处理的行为和神经指标, 聚焦老年人预测误差成本的产生机制, 主要从副中央凹视觉、工作记忆负荷及语言能力三方面解释预测误差成本产生的原因。研究成果对构建汉语阅读的毕生发展模型有重要意义。     

Effects of divided attention and word concreteness on correct recall and false memory reports

Lists of thematically related words were presented to participants with or without a concurrent task. In Experiments 1 and 2, respectively, English or Spanish word lists were either low or high in concreteness (concrete vs abstract words) and were presented, respectively, auditorily or visually for study. The addition of a concurrent visual or auditory task, respectively, substantially reduced correct recall and doubled the frequency of false memory reports (nonstudied critical or theme words). Divided attention was interpreted as having reduced the opportunity for participants to monitor successfully their elicitations of critical associates. Comparisons of concrete and abstract lists revealed significantly more recalls of false memories for abstract than concrete word lists. Comparisons between two levels of attention, two levels of word concreteness, and two presentation modalities failed to support the "more is less" effect by which enhanced correct recall is accompanied by increased frequencies of false memories.     

Collaboration reduces the frequency of false memories in older and younger adults

Older (mean age = 74.23) and younger (mean age = 33.50) participants recalled items from 6 briefly exposed household scenes either alone or with their spouses. Collaborative recall was compared with the pooled, nonredundant recall of spouses remembering alone (nominal groups). The authors examined hits, self-generated false memories, and false memories produced by another person's (actually a computer program's) misleading recollections. Older adults reported fewer hits and more self-generated false memories than younger adults. Relative to nominal groups, older and younger collaborating groups reported fewer hits and fewer self-generated false memories. Collaboration also reduced older people's computer-initiated false memories. The memory conversations in the collaborative groups were analyzed for evidence that collaboration inhibits the production of errors and/or promotes quality control processes that detect and eliminate errors. Only older adults inhibited the production of wrong answers, but both age groups eliminated errors during their discussions. The partners played an important role in helping rememberers discard false memories in older and younger couples. The results support the use of collaboration to reduce false recall in both younger and older adults.     

False recognition in younger and older adults: Exploring the characteristics of illusory memories

Roediger and McDermott (1995) demonstrated that when subjects hear a list of associates to a “theme word” that has itself not been presented, they frequently claim to recollect having heard the nonpresented theme word on the study list. In Experiment 1, we found that asking subjects to explain theirremember responses, by writing down exactly what they remembered about the item’s presentation at study, did not significantly diminish the rate ofremember false alarms to nonpresented theme words. We also found that older adults were relatively more susceptible than younger adults to this false-recognition effect. Subjects’ explanations suggested that both veridical and illusory memories were predominantly composed of associative information as opposed to sensory and contextual detail. In Experiment 2, we obtained quantitative evidence for this conclusion, using a paradigm in which subjects were asked focused questions about the contents of their recollective experience. Lastly, we found that both younger and older adults recalled more sensory and contextual detail in conjunction with studied items than with nonpresented theme words, although these differences were less pronounced in older adults.     

The production of false recognition and the associated state of consciousness following encoding in a naturalistic context in aging

Using virtual reality, we implemented a naturalistic variant of the DRM paradigm in young and older adults to evaluate false recall and false recognition. We distinguished false recognition related to the highest semantic association (the critical lures), semantic similarity (i.e. items that belong to the same semantic category), and perceptual similarity (i.e. items that are similar, but not identical in terms of shape or color). The data revealed that younger adults recalled and recognized more correct elements than older adults did while the older adults intruded more critical items than younger adults. Both age groups produced false recognition related to the critical items, followed by perceptually and then semantically related items. False recognitions were highly recollective as they were mainly associated with a sense of remembering, even more so in older adults than in young adults. The decline of executive functions and working memory predicted age-related increases in false memories.     

Influence of suggestion in the DRM paradigm: what state of consciousness is associated with false memory?

We assessed the effect of suggestion on the Deese–Roediger–McDermott paradigm and associated it with the Remember–Know–Guess paradigm. Undergraduate students were given either lists of semantically related words or texts containing these words. After the recall task, if participants did not produce the critical lure, the experimenter suggested that the word had been present, using either a question (moderate suggestion) or an assertion (strong suggestion); these conditions were compared to a condition without suggestion. Afterwards, participants took a recognition test. The results showed that strong suggestions lead to more false recognitions than other conditions and the state of consciousness associated with false recognitions tends to be a feeling of knowing rather than remembering, regardless of the verbal version (list or text). Therefore moderate suggestions did not lead to more false recognitions compare to no suggestion. We discuss the impact of suggestion on consciousness associated with false memories.     

Memory for general and specific value information in younger and older adults: Measuring the limits of strategic control

The ability to selectively remember important information is a critical function of memory. Although previous research has suggested that older adults are impaired in a variety of episodic memory tasks, recent work has demonstrated that older adults can selectively remember high-value information. In the present research, we examined how younger and older adults selectively remembered words with various assigned numeric point values, to see whether younger adults could remember more specific value information than could older adults. Both groups were equally good at recalling point values when recalling the range of high-value words, but younger adults outperformed older adults when recalling specific values. Although older adults were more likely to recognize negative value words, both groups exhibited control by not recalling negative value information. The findings suggest that although both groups retain high-value information, older adults rely more on gist-based encoding and retrieval operations, whereas younger adults are able to remember specific numeric value information.     

Conscious and unconscious lexical retrieval blocking in younger and older adults

The effects of orthographically overlapping prime words in a word fragment completion task (modified from S. M. Smith & D. R. Tindell, 1997) were studied in younger and older adults. Participants studied words and then completed word fragments corresponding to those words. Fragments were preceded by a blocking, unrelated, or neutral prime. In Experiment 1, all participants were slower and less likely to complete the word fragments correctly in the blocking prime condition. Older adults also were more likely to use the blocking prime to incorrectly complete the word fragment compared with younger adults, even when warned against doing so (Experiment 2). Experiment 3 used a masked priming paradigm in younger adults to examine whether conscious processing of the prime word was necessary to produce blocking effects. Reliable blocking effects were obtained, including an intrusion rate similar to that observed in older adults in the first two experiments. These results suggest that certain aspects of word-finding failures in normal aging may be related to the reduced ability to control the activation of a lexical competitor when attempting to retrieve a target word.     

Developmental reversals in false memory: now you see them, now you don't!

A developmental reversal in false memory is the counterintuitive phenomenon of higher levels of false memory in older children, adolescents, and adults than in younger children. The ability of verbatim memory to suppress this age trend in false memory was evaluated using the Deese-Roediger-McDermott (DRM) paradigm. Seven and 11-year-old children studied DRM lists either in a standard condition (whole words) that normally produces high levels of false memory or in an alternative condition that should enhance verbatim memory (word fragments). Half the children took 1 recognition test, and the other half took 3 recognition tests. In the single-test condition, the typical age difference in false memory was found for the word condition (higher false memory for 11-year-olds than for 7-year-olds), but in the word fragment condition false memory was lower in the older children. In the word condition, false memory increased over successive recognition tests. Our findings are consistent with 2 principles of fuzzy-trace theory's explanation of false memories: (a) reliance on verbatim rather than gist memory causes such errors to decline with age, and (b) repeated testing increases reliance on gist memory in older children and adults who spontaneously connect meaning across events.     

Effects of word frequency and visual complexity on eye movements of young and older Chinese readers

Research using alphabetic languages shows that, compared to young adults, older adults employ a risky reading strategy in which they are more likely to guess word identities and skip words to compensate for their slower processing of text. However, little is known about how ageing affects reading behaviour for naturally unspaced, logographic languages like Chinese. Accordingly, to assess the generality of age-related changes in reading strategy across different writing systems we undertook an eye movement investigation of adult age differences in Chinese reading. Participants read sentences containing a target word (a single Chinese character) that had a high or low frequency of usage and was constructed from either few or many character strokes, and so either visually simple or complex. Frequency and complexity produced similar patterns of influence for both age groups on skipping rates and fixation times for target words. Both groups therefore demonstrated sensitivity to these manipulations. But compared to the young adults, the older adults made more and longer fixations and more forward and backward eye movements overall. They also fixated the target words for longer, especially when these were visually complex. Crucially, the older adults skipped words less and made shorter progressive saccades. Therefore, in contrast with findings for alphabetic languages, older Chinese readers appear to use a careful reading strategy according to which they move their eyes cautiously along lines of text and skip words infrequently. We propose they use this more careful reading strategy to compensate for increased difficulty processing word boundaries in Chinese.