Using warnings to reduce categorical false memories in younger and older adults

Warnings about memory errors can reduce their incidence, although past work has largely focused on associative memory errors. The current study sought to explore whether warnings could be tailored to specifically reduce false recall of categorical information in both younger and older populations. Before encoding word pairs designed to induce categorical false memories, half of the younger and older participants were warned to avoid committing these types of memory errors. Older adults who received a warning committed fewer categorical memory errors, as well as other types of semantic memory errors, than those who did not receive a warning. In contrast, young adults' memory errors did not differ for the warning versus no-warning groups. Our findings provide evidence for the effectiveness of warnings at reducing categorical memory errors in older adults, perhaps by supporting source monitoring, reduction in reliance on gist traces, or through effective metacognitive strategies.     

Variations in processing resources and resistance to false memories in younger and older adults

The influence of available processing resources on the resistance to false memories (FMs) for lists of semantically related items associated with a non-presented critical lure was examined in younger and older adults. Reducing the available resources at encoding in younger adults (Experiments 1 and 2) led to a performance similar to that of older adults (i.e., higher rates of FMs in addition to reduced rates of correct recall). However, increasing the available resources (Experiments 2 and 3) led to improvements in the rates of correct recall in both age groups and decreased the probability of FMs in younger adults, although warnings had to be added in older adults to obtain similar effects on FMs. Parallel influences on a post-recall test asking participants to report items that they had thought of but did not recall were also found. The influence of available cognitive resources for memory accuracy is also discussed with respect to activation-monitoring (e.g., McDermott & Watson, 2001) and fuzzy-trace (e.g., Brainerd & Reyna, 2002) accounts of age-related increased in false memories.     

Presentation modality effect on false memories in younger and older adults: the use of an inference paradigm

Classically, false memories are studied using the DRM paradigm (Deese, 1959; Roediger & McDermott, 1995), involving use of words lists. The words of each list are linked to a critical word not presented. Participants create a false memory in recognising and/or recalling this critical word. In most cases older adults have more false memories than younger adults in this paradigm. To use less strategy-dependent material, we compared predictive inferences activated during text reading in young and healthy older participants. For example, in the sentence "The fragile porcelain vase was thrown against the wall" the predictive inference was that the vase is broken. After reading or hearing the texts, the participants had false memories in recalling and/or recognising the predictive inferences. Older adults had more false recognitions than younger adults when they read or heard the text. However, the difference did not reach significance with the cued recalled task. It is concluded that, in more ecological situations such as text reading, abilities in older adults can be preserved.     

Phenomenological characteristics of emotional memories in younger and older adults

Older adults sometimes show a “positivity effect” in memory, remembering proportionally more positive information than younger adults. Using a modified Memory Characteristics Questionnaire, this study examined whether emotional valence impacts the phenomenological qualities of young and older adults’ memories. Ageing did not impact the effect of valence on the qualities of high-arousal memories. However, ageing sometimes impacted subjective memory for details of low-arousal memories: In Experiment 2, older adults reported remembering more thoughts, feelings, and temporal order details about positive low-arousal stimuli, while young adults’ ratings for those dimensions were higher for negative low-arousal stimuli. These findings suggest that valence most readily affects the qualities of young and older adults’ emotional memories when those memories are low in arousal.     

The allure of the alignable: younger and older adults' false memories of choice features

When making choices, people often try to directly compare the features of different options rather than evaluating each option separately. Not every feature has an analogous (or alignable) feature in the other option, however. In this study, both younger and older adults filled in such gaps when remembering, creating features in the other option to contrast with existing features. Thus, participants had a tendency to remember choice options as more comparable than they originally were. High performance on tasks tapping strategic processing was associated with a pattern of mostly feature-based comparisons during choice for older adults but with a pattern of mostly option-based comparisons for younger adults. This pattern suggests that younger and older adults' comparison processes are influenced by different goals.     

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.     

Item-specific processing reduces false memories

We examined the effect of item-specific and relational encoding instructions on false recognition in two experiments in which the DRM paradigm was used (Deese, 1959; Roediger & McDermott, 1995). Type of encoding (item-specific or relational) was manipulated between subjects in Experiment 1 and within subjects in Experiment 2. Decision-based explanations (e.g., the distinctiveness heuristic) predict reductions in false recognition in between-subjects designs, but not in within-subjects designs, because they are conceptualized as global shifts in decision criteria. Memory-based explanations predict reductions in false recognition in both designs, resulting from enhanced recollection of item-specific details. False recognition was reduced following item-specific encoding instructions in both experiments, favoring a memory-based explanation. These results suggest that providing unique cues for the retrieval of individual studied items results in enhanced discrimination between those studied items and critical lures. Conversely, enhancing the similarity of studied items results in poor discrimination among items within a particular list theme. These results are discussed in terms of the item-specific/ relational framework (Hunt & McDaniel, 1993).     

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.     

Collective memories of three wars in United States history in younger and older adults

A collective memory is a representation of the past that is shared by members of a group. We investigated similarities and differences in the collective memories of younger and older adults for three major wars in U.S. history (the Civil War, World War II, and the Iraq War). Both groups were alive during the recent Iraq War, but only the older subjects were alive during World War II, and both groups learned about the Civil War from historical sources. Subjects recalled the 10 most important events that occurred during each war and then evaluated the emotional valence, the relative importance, and their level of knowledge for each event. They also estimated the percentage of people that would share their memory of each event within their age group and the other age group. Although most historical events were recalled by fewer than 25 % of subjects, younger and older adults commonly recalled a core set of events for each war that conform to a narrative structure that may be fundamental to collective remembering. Younger adults showed greater consensus in the events that they recalled for all three wars, relative to older adults, but there was less consensus in both groups for the Iraq War. Whereas younger adults recalled more specific events of short duration, older adults recalled more extended and summarized events of long duration. Our study shows that collective memories can be studied empirically and can differ depending on whether the events are experienced personally or learned from historical sources.     

Item-specific processing reduces false recognition in older and younger adults: Separating encoding and retrieval using signal detection and the diffusion model

Our study examined processing effects in improving memory accuracy in older and younger adults. Specifically, we evaluated the effectiveness of item-specific and relational processing instructions relative to a read-only control task on correct and false recognition in younger and older adults using a categorized-list paradigm. In both age groups, item-specific and relational processing improved correct recognition versus a read-only control task, and item-specific encoding decreased false recognition relative to both the relational and read-only groups. This pattern was found in older adults despite overall elevated rates of false recognition. We then applied signal-detection and diffusion-modeling analyses, which separately utilized recognition responses and the latencies to those responses to estimate contributions of encoding and monitoring processes on recognition decisions. Converging evidence from both analyses demonstrated that item-specific processing benefits to memory accuracy were due to improvements of both encoding (estimates of d′ and drift rate) and monitoring (estimates of lambda and boundary separation) processes, and, importantly, occurred similarly in both younger and older adults. Thus, older and younger adults showed similar encoding-based and test-based benefits of item-specific processing to enhance memory accuracy.     

Stereotype threat reduces false recognition when older adults are forewarned

Exposing older adults to ageing stereotypes can reduce their memory for studied information—a phenomenon attributed to stereotype threat—but little is known about stereotype effects on false memory. Here, we assessed ageing stereotype effects on the Deese-Roediger-McDermott false memory illusion. Older adults studied lists of semantically associated words, and then read a passage about age-related memory decline (threat condition) or an age-neutral passage (control condition). They then took a surprise memory test with a warning to avoid false recognition of non-studied associates. Relative to the control condition, activating stereotype threat reduced the recognition of both studied and non-studied words, implicating a conservative criterion shift for associated test words. These results indicate that stereotype threat can reduce false memory, and they help to clarify mixed results from prior ageing research. Consistent with the regulatory focus hypothesis, threat motivates older adults to respond more conservatively when error-prevention is emphasised at retrieval.     

Word-list-learning performance in younger and older adults: intra-individual performance variability and false memory

We investigated the word-list-learning performance of younger and older adults over 4 consecutive days at different times of day to study age-related differences in consistency of performance over time and the influence of circadian variation on performance. Eighteen younger (M age, 23.4 years) and 18 older (M age, 73.3 years) men and women participated. The start time of testing alternated between morning and early evening across the 4 days of testing. On each test day, participants learned a different list of 15 unrelated words over four learning trials. As expected, younger adults performed better than older adults on immediate recall, delayed recall, and recognition. Contrary to our expectations, time of day did not significantly influence recall or recognition performance in either the older or younger adults. Older adults did show a greater incidence of false memory (i.e., previously learned list intrusions in free recall and false alarms in recognition) than younger adults. Older adults also exhibited greater intra-individual performance variability on the measures of false memory across test days. This variability was not related to circadian variation. False memory and variability of performance have both been linked to frontal systems dysfunction. The findings presented here are consistent with the notion that changes in cognition with aging in part reflect age-related decline in frontal lobe function.     

Episodic intertrial learning of younger and older adults: Effects of word frequency

ABSTRACT

Older adults have a demonstrable episodic memory deficit. The present study aimed to investigate whether the age deficit in episodic memory was influenced by stimulus characteristics known to produce differences in memory performance in younger adults, specifically word frequency. An intertrial paradigm was used whereby participants studied high- or low-frequency lists over several study-test trials, and the loss and gain of individual items was measured across trials; putative measures of consolidation and encoding. The results show that high-frequency words are recalled significantly better than low-frequency words. Older adults acquired high-frequency words at a greater rate across trials than they did for low-frequency words, an effect not evident in the younger adults. Older adults were found to have deficits in both encoding and consolidation as measured by losses and gains of items across trials. The results support the inter-item association theory of the word frequency effect on recall, with the age differences suggesting that memory deficits are sensitive to stimuli characteristics – one interpretation being that the ease of processing of the stimuli at encoding facilitates later recall.     

Memory complaints in younger and older adults

Two samples of older and younger subjects were administered a series of memory tasks and questionnaires tapping their perceptions about their own memory functioning. As in previous research, memory performance was usually better in the younger than in the older sample. In contrast, perceptions about memory varied little as a function of age, and these subjective reports were not related to objective memory performances. These results are relevant to theories that metacognition plays an important role in mediating performance declines with advancing age. If metacognition is implicated in age-related memory differences, it is some aspect of metacognition other than long-term beliefs about memory functioning (e. g. short-term perceptions that occur while attempting to perform memory tasks).     

The ironic effect of guessing: increased false memory for mediated lists in younger and older adults

Younger and older adults studied lists of words directly (e.g., creek, water) or indirectly (e.g., beaver, faucet) related to a nonpresented critical lure (CL; e.g., river). Indirect (i.e., mediated) lists presented items that were only related to CLs through nonpresented mediators (i.e., directly related items). Following study, participants completed a condition-specific task, math, a recall test with or without a warning about the CL, or tried to guess the CL. On a final recognition test, warnings (vs. math and recall without warning) decreased false recognition for direct lists, and guessing increased mediated false recognition (an ironic effect of guessing) in both age groups. The observed age-invariance of the ironic effect of guessing suggests that processes involved in mediated false memory are preserved in aging and confirms the effect is largely due to activation in semantic networks during encoding and to the strengthening of these networks during the interpolated tasks.     

Auditory negative priming in younger and older adults

Two experiments are reported in which performance of old and young adults in an auditory negative priming task was compared. Auditory negative priming was not smaller in old than in young adults. This result was independent of whether or not conditions were present that had previously been assumed to favour episodic retrieval, as opposed to inhibitory processes, as a basis of the negative priming phenomenon. The data from the present auditory negative priming experiments are incompatible with the global assumption that the efficiency of inhibitory attentional processes in general diminishes across the adult life span.     

Random noun generation in younger and older adults

We examined age-related changes of executive functions by means of random noun generation. Consistent with previous observations on random letter generation, older participants produced more prepotent responses than younger ones. In the case of random noun generation, prepotent responses are nouns of the same category as the preceding noun. In contrast to previous observations, older participants exhibited stronger repetition avoidance and a stronger tendency toward local evenness—that is, toward equal frequencies of the alternative responses even in short subsequences. These data suggest that at higher adult age inhibition of prepotent responses is impaired. In addition, strategic attentional processes of response selection are strengthened, in particular the application of a heuristic for randomness. In this sense response selection is more controlled in older than in younger adults.     

Part-set cuing effects in younger and older adults

In 3 experiments, the authors examined part-set cuing effects in younger and older adults. Participants heard lists of category exemplars and later recalled them. Recall was uncued or cued with a subset of studied items. In Experiment 1, participants were cued with some of the category names, and they remembered fewer never-cued categories than a free-recall condition. In Experiment 2, a similar effect was observed for category exemplar cues. There was also an age difference: By some measures, a small number of cues impaired older adults more than younger. Experiment 3 replicated this result and found that older adults were disproportionately slow in the presence of cues. Across experiments, older adults showed robust part-set cuing effects, and sometimes, they were disproportionately impaired by cues.