Proactive effects of memory in young and older adults: the role of change recollection

Remembering change: Interdependence between change awareness and meaningful connection in achieving proactive facilitation

Two experiments investigated proactive facilitation (PF) or proactive interference (PI) in the recall of recently learned targets, under conditions of assessing the detection and recollection of target changes across two learning phases (with A-B/A-D word pairs). Some changes established meaningful connections across the phases; others did not. Task instructions on the subsequent cued-recall test (Experiment 1) or during Phase 2 study (Experiment 2) guided participants (university students) to monitor and report the changes. Accuracy in cued recall conditionalized on measures of change awareness replicated previous findings in establishing conditions for PF and PI. However, PF was much reduced for unconnected materials. Moreover, when change recollection failed, PI occurred even under conditions of meaningful connections (Experiment 1). Discussion emphasizes this interdependence of meaningfulness of connections and change awareness in influencing whether and how memory for earlier events affects memory for more recent ones.

Correcting fake news headlines after repeated exposure: memory and belief accuracy in younger and older adults

The efficacy of fake news corrections in improving memory and belief accuracy may depend on how often adults see false information before it is corrected. Two experiments tested the competing predictions that repeating fake news before corrections will either impair or improve memory and belief accuracy. These experiments also examined whether fake news exposure effects would differ for younger and older adults due to age-related differences in the recollection of contextual details. Younger and older adults read real and fake news headlines that appeared once or thrice. Next, they identified fake news corrections among real news headlines. Later, recognition and cued recall tests assessed memory for real news, fake news, if corrections occurred, and beliefs in retrieved details. Repeating fake news increased detection and remembering of corrections, correct real news retrieval, and erroneous fake news retrieval. No age differences emerged for detection of corrections, but younger adults remembered corrections better than older adults. At test, correct fake news retrieval for earlier-detected corrections was associated with better real news retrieval. This benefit did not differ between age groups in recognition but was greater for younger than older adults in cued recall. When detected corrections were not remembered at test, repeated fake news increased memory errors. Overall, both age groups believed correctly retrieved real news more than erroneously retrieved fake news to a similar degree. These findings suggest that fake news repetition effects on subsequent memory accuracy depended on age differences in recollection-based retrieval of fake news and that it was corrected.

The influence of repeated study and repeated testing on the testing effect and the transfer effect over time

Many studies have shown that compared to the restudy condition (RS), retrieval practice (RP) enhances the long-retention memory of retrieved items (i.e., the testing effect), and facilitates later memory of non-retrieved but related items (i.e., the transfer effect). However, previous studies have usually used repeated study and repeated testing, which are included in study-testing cycles. Therefore, it is unclear to what extent the factors of repeated study and repeated testing influence testing and transfer effects over time. In this study, participants studied sentences that described various episodes, then tested a half subset of the original sentences under three conditions (RP, RS, control). After retention intervals of 10 min, 1 day and 7 days, they recalled all of the information in the sentences. The results showed that the testing effect was enhanced by repeated study or repeated testing, while the transfer effect occurred only after both repeated study and repeated testing. Furthermore, repeated study or repeated testing slowed down the forgetting of retrieved items, while the forgetting of non-retrieved items occurred after both repeated study and repeated testing. The testing effect increased over time, but the transfer effect remained relatively stable over time. These results clarified different roles of multiple study repetitions and testing opportunities in the testing effect and the transfer effect, and suggest that the repeated retrieval could be combined with repeated study to optimally promote long-term retention of the memory of tested and non-tested items.

Early Intervention in Cognitive Aging with Strawberry Supplementation

Late-life dementia is a growing public health concern lacking effective treatment. Neurodegenerative disorders such as Alzheimer's disease (AD) develop over a preclinical period of many years beginning in midlife. The prevalence of insulin resistance, a prominent risk factor for late-life dementia, also accelerates in middle-age. Consumption of berry fruits, including strawberries, has been shown to influence metabolism as well as cognitive performance suggesting potential to mitigate risk for dementia. In this controlled trial, we enrolled overweight middle-aged men and women with insulin resistance and subjective cognitive decline and performed a 12-week intervention with daily administration of whole-fruit strawberry powder. Diet records showed that participants in both groups maintained the prescribed abstinence from berry product consumption outside the study. We observed diminished memory interference (p = 0.02; Cohen's f = 0.45) and a reduction of depressive symptoms (p = 0.04; Cohen's f = 0.39) for the strawberry-treated participants; benefits consistent with improved executive ability. However, there was no effect of the intervention on metabolic measures, possibly a consequence of the sample size, length of the intervention, or comparatively low anthocyanin dose. Anti-inflammatory actions of anthocyanins were considered as a primary mechanistic factor. The findings support the notion that strawberry supplementation has a role in dementia risk reduction when introduced in midlife. However, further investigation with longer intervention periods, larger samples, and differing dosing regimens will be required to assess the benefits of strawberry intake with respect to cognition and metabolic function in the context of aging.

Time separating spatial memories does not influence their integration in humans

Humans can navigate through similar environments-like grocery stores-by integrating across their memories to extract commonalities or by differentiating between each to find idiosyncratic locations. Here, we investigate one factor that might impact whether two related spatial memories are integrated or differentiated: Namely, the temporal delay between experiences. Rodents have been shown to integrate memories more often when they are formed within 6 hours of each other. To test if this effect influences how humans spontaneously integrate spatial memories, we had 131 participants search for rewards in two similar virtual environments. We separated these learning experiences by either 30 minutes, 3 hours, or 27 hours. Memory integration was assessed three days later. Participants were able to integrate and simultaneously differentiate related memories across experiences. However, neither memory integration nor differentiation was modulated by temporal delay, in contrast to previous work. We further showed that both the levels of initial memory reactivation during the second experience and memory generalization to novel environments were comparable across conditions. Moreover, perseveration toward the initial reward locations during the second experience was related positively to integration and negatively to differentiation-but again, these associations did not vary by delay. Our findings identify important boundary conditions on the translation of rodent memory mechanisms to humans, motivating more research to characterize how even fundamental memory mechanisms are conserved and diverge across species.

Semantic relatedness retroactively boosts memory and promotes memory interdependence across episodes

Two fundamental issues in memory research concern when later experiences strengthen or weaken initial memories and when the two memories become linked or remain independent. A promising candidate for explaining these issues is semantic relatedness. Here, across five paired-associate learning experiments (N=1000), we systematically varied the semantic relatedness between initial and later cues, initial and later targets, or both. We found that learning retroactively benefited long-term memory performance for semantically related words (vs. unshown control words), and these benefits increased as a function of relatedness. Critically, memory dependence between initial and later pairs also increased with relatedness, suggesting that pre-existing semantic relationships promote interdependence for memories formed across episodes. We also found that modest retroactive benefits, but not interdependencies, emerged when subjects learned via studying rather than practice testing. These findings demonstrate that semantic relatedness during new learning retroactively strengthens old associations while scaffolding new ones into well-fortified memory traces.

Neural Reinstatement of Overlapping Memories in Young and Older Adults

When we update our episodic memories with new information, mnemonic competition between old and new memories may result because of the presence of shared features. Behavioral studies suggest that this competition can lead to proactive interference, resulting in unsuccessful memory updating, particularly for older adults. It is difficult with behavioral data alone to measure the reactivation of old, overlapping memories during retrieval and its impact on memory for new memories. Here, we applied encoding-retrieval representational similarity (ERS) analysis to EEG data to estimate event-specific encoding-related neural reinstatement of old associations during the retrieval of new ones and its impact on memory for new associations in young and older adults. Our results showed that older adults' new associative memory performance was more negatively impacted by proactive interference from old memories than that of young adults. In both age groups, ERS for old associative memories was greater for trials for which new associative memories were forgotten than remembered. In contrast, ERS for new associative memories was greater when they were remembered than forgotten. In addition, older adults showed relatively attenuated target (i.e., new associates) and lure (i.e., old associates) ERS effects compared to younger adults. Collectively, these results suggest that the neural reinstatement of interfering memories during retrieval contributes to proactive interference across age, whereas overall attenuated ERS effect in older adults might reflect their reduced memory fidelity.

The influence of long-term memory on working memory: Age-differences in proactive facilitation and interference

Prior learning can hinder subsequent memory, especially when there is conflict between old and new information. The ability to handle this proactive interference is an important source of differences in memory performance between younger and older adults. In younger participants, Oberauer et al. (2017, Journal of Experimental Psychology: Learning, Memory, and Cognition, 43[1], 1) report evidence of proactive facilitation from previously learned information in a working memory task in the absence of proactive interference between long-term and working memory. In the present work, we examine the generality of these findings to different stimulus materials and to older adults. Participants first learned image-word associations and then completed an image-word working memory task. Some pairs were the same as those initially learned, for which we expected facilitation relative to previously unencountered pairs. Other pairs were made up of previously learned elements in different combinations, for which we might expect interference. Younger and older participants showed similar levels of facilitation from previously learned associations relative to new pairs. In addition, older participants exhibited proactive interference from long-term to working memory, whereas younger participants exhibited facilitation, even for pairings that conflicted with those learned earlier in the experiment. These findings confirm older adults' greater susceptibility to proactive interference and we discuss the theoretical implications of younger adults' apparent immunity to interference.

Older and younger adults' revision of health misconceptions

Although ample younger adult research has detailed effective strategies for revising misconceptions, research with older adults is less extensive. Older adults may be less able to correct errors in knowledge due to age-related changes in cognition, but it is also possible that older adults' revision of misconceptions has been limited by methodologies which do not provide adequate support for correction. In two experiments, we examined how older and younger adults revise health-related misconceptions when provided with cognitive support in the form of explicit detailed feedback and an immediate test. Older and younger adults in Experiment 1 answered true/false health statements, received feedback with a detailed explanation of the correct response, took an additional test on the same statements immediately following the initial test, and completed a final test 1-week later. Older and younger adults corrected a similar proportion of misconceptions immediately and maintained most of those revisions across a 1-week delay. In Experiment 2, older adults corrected the same proportion of misconceptions on the final test regardless of whether or not they received a test immediately following feedback. Overall, older adults revised health misconceptions as effectively as did younger adults but variables influencing correction (e.g., belief in feedback) may differ.

Resisting misinformation via discrepancy detection: effects of an unaware suspicion cue

Previous studies have shown that contaminating effects of misinformation can be reduced by consciously raising the awareness of eyewitnesses to the discrepancy between the misinformation and the original information (e.g., Tousignant, J. P., Hall, D., & Loftus, E. F. [1986]. Discrepancy detection and vulnerability misleading postevent information. Memory & Cognition, 14(4), 329-338. doi:10.3758/BF03202511). We tested whether similar effects could be obtained without conscious awareness, by drawing on the metaphor "something smells fishy" linking fishy smells and suspicion (Lee, S. W. S., & Schwarz, N. [2012]. Bidirectionality, mediation, and moderation of metaphorical effects: The embodiment of social suspicion and fishy smells. Journal of Personality and Social Psychology, 103(5), 737-749. doi:10.1037/a0029708). In a pilot study, we established the replicability and generality of previous findings concerning this metaphorical link. We then examined the effects of the smell-suspicion link on susceptibility to misleading post-event information using the misinformation paradigm. Here, the "something smells fishy" metaphor was used to invoke suspicion and increase discrepancy detection. Forty-eight hours after viewing an event, participants received misinformation in a room sprayed with either a fishy or a neutral smell. As expected, unaware exposure to the fishy smell (compared to the neutral smell) increased discrepancy detection (measured indirectly) and resistance to the contaminating effects of misinformation, eliminating misinformation interference and lowering suggestibility on the final test.

The role of prior-event retrieval in encoding changed event features

When people experience everyday activities, their comprehension can be shaped by expectations that derive from similar recent experiences, which can affect the encoding of a new experience into memory. When a new experience includes changes-such as a driving route being blocked by construction-this can lead to interference in subsequent memory. One potential mechanism of effective encoding of event changes is the retrieval of related features from previous events. Another such mechanism is the generation of a prediction error when a predicted feature is contradicted. In two experiments, we tested for effects of these two mechanisms on memory for changed features in movies of everyday activities. Participants viewed movies of an actor performing everyday activities across two fictitious days. Some event features changed across the days, and some features violated viewers' predictions. Retrieval of previous event features while viewing the second movie was associated with better subsequent memory, providing evidence for the retrieval mechanism. Contrary to our hypotheses, there was no support for the error mechanism: Prediction error was not associated with better memory when it was observed correlationally (Experiment 1) or directly manipulated (Experiment 2). These results support a key role for episodic retrieval in the encoding of new events. They also indicate boundary conditions on the role of prediction errors in driving new learning. Both findings have clear implications for theories of event memory.

How Proactive Interference during New Associative Learning Impacts General and Specific Memory in Young and Old

Some prior research has found that older adults are more susceptible to proactive interference than young adults. The current study investigated whether age-related deficits in pFC-mediated cognitive control processes that act to detect and resolve interference underlie increased susceptibility to proactive interference in an associative memory task. Young and older adults were scanned while tasked with remembering which associate (face or scene) objects were paired with most recently during study, under conditions of high, low, or no proactive interference. After scanning, participants' memory was tested for varying levels of episodic detail about the pairings (i.e., target category vs. specific target category vs. specific target associate). Young and older adults were similarly susceptible to proactive interference. Memory for both the general target category and the specific target associate worsened as the level of proactive interference increased, with no robust age differences. For both young and older adults, the left ventrolateral pFC, which has been indicated in controlled retrieval of goal-relevant conceptual representations, was sensitive to increasing levels of interference during encoding but was insensitive to associative memory accuracy. Consistent with the Compensation-Related Utilization of Neural Circuits Hypothesis model of cognitive aging, the ventromedial pFC, which is involved in the monitoring of internally generated information, was recruited more by older than young adults to support the successful retrieval of target-object pairs at lower levels of proactive interference. Collectively, these results suggest that some older adults are able to engage in the cognitive control processes necessary to resolve proactive interference to the same extent as young adults.

The role of attentional fluctuation during study in recollecting episodic changes at test

Changes in stimulus features across episodes can lead to proactive interference. One potential way to avoid such interference is to detect and later recollect changes. The Memory-for-Change framework assumes that attention during encoding is necessary for detecting and later recollecting change. We tested this assumption in the current experiment by assessing the covariation of attention and change recollection in a large undergraduate sample (N=132). Participants studied a list of word pairs comprised of four seamless blocks. Some word pairs repeated across all four blocks (A-B⁴), some were unique to each block (C-D), and some pairs repeated across the first three blocks with a changed response in the fourth block (A-B³, A-D). To measure attention during study, participants periodically responded to probes asking whether they were on- or off-task. Participants then completed a cued recall test of responses from the fourth study block. To measure change recollection, participants were asked to identify which pairs changed during study and to report the earlier responses for pairs they identified as changed. Replicating prior findings, recollecting change was associated with proactive facilitation in recall of the most recent responses. Extending these findings, the frequency of on-task reports was positively associated with cued recall accuracy and change recollection in both within- and between-subjects comparisons. Together, these findings implicate a critical role for self-reported attention during study in change recollection, which is associated with proactive facilitation in recall of changed responses.

Interference between overlapping memories is predicted by neural states during learning

One of the primary contributors to forgetting is interference from overlapping memories. Intuitively, this suggests-and prominent theoretical models argue-that memory interference is best avoided by encoding overlapping memories as if they were unrelated. It is therefore surprising that reactivation of older memories during new encoding has been associated with reduced memory interference. Critically, however, prior studies have not directly established why reactivation reduces interference. Here, we first developed a behavioral paradigm that isolates the negative influence that overlapping memories exert during memory retrieval. We then show that reactivating older memories during the encoding of new memories dramatically reduces this interference cost at retrieval. Finally, leveraging multiple fMRI decoding approaches, we show that spontaneous reactivation of older memories during new encoding leads to integration of overlapping memories and, critically, that integration during encoding specifically reduces interference between overlapping, and otherwise competing, memories during retrieval.

Reminders can enhance or impair episodic memory updating: a memory-for-change perspective

The Memory-for-Change framework proposes that retrieving episodic memories can facilitate new learning when changes between existing memories and new information are integrated during encoding and later recollected. Four experiments examined whether reminders could improve memory updating and enhance new learning. Participants studied two study lists of word pairs and were given a cued recall test on responses from both lists. Reminders of List 1 words pairs (A-B) appeared immediately before List 2 words pairs that included repeated cues and changed responses (A-D). Across experiments, we varied the types of reminders to determine whether differences in their effectiveness as retrieval cues would influence memory for the list membership of responses. We found that presenting intact reminders (cue-response) enhanced the memory benefits associated with recollection-based retrieval of changes relative to when no reminders appeared and when partial reminders (cue-only) appeared with and without feedback. Importantly, cue-response reminders benefitted memory when they were recognised in List 2 and when changes were later recollected. This suggests that integrative encoding can be facilitated when substantial environmental support is available to cue retrieval of existing memories. These findings have practical implications for understanding which reminders best aid the correction of memories for inaccurate information.

Modeling age differences in effects of pair repetition and proactive interference using a single parameter

In this article, we apply the REM model (Shiffrin & Steyvers, 1997) to age differences in associative memory. Using Criss and Shiffrin's (2005) associative version of REM, we show that in a task with pairs repeated across 2 study lists, older adults' reduced benefit of pair repetition can be produced by a general reduction in the diagnosticity of information stored in memory. This reduction can be modeled similarly well by reducing the overall distinctiveness of memory features, or by reducing the accuracy of memory encoding. We report a new experiment in which pairs are repeated across 3 study lists and extend the model accordingly. Finally, we extend the model to previously reported data using the same task paradigm, in which the use of a high-association strategy introduced proactive interference effects in young adults but not older adults. Reducing the diagnosticity of information in memory also reduces the proactive interference effect. Taken together, the modeling and empirical results reported here are consistent with the claim that some age differences that appear to be specific to associative information can be produced via general degradation of information stored in memory. The REM model provides a useful framework for examining age differences in memory as well as harmonizing seemingly conflicting prior modeling approaches for the associative deficit. (PsycINFO Database Record

Memory guides the processing of event changes for older and younger adults

Memory for related past experiences can guide current perceptions. However, memory can lead one astray if situational features have changed. Thus, to adaptively use memory to guide perception, one needs to retrieve relevant memories and also to register differences between remembered and current events. Event Memory Retrieval and Comparison Theory proposes that observers associatively activate memories of related previous episodes, and that this guides their ongoing perception. Conflicts between previous and current event features can hurt immediate performance, but if changes are registered and encoded they can lead to highly effective encoding of the prior event, current event, and their relationship. Disruption of these mechanisms could play a role in older adults' greater susceptibility to event memory interference. Two experiments tested these hypotheses by asking participants to watch movies depicting two fictive days of an actor. Some activities were repeated across days, others were repeated with a changed feature (e.g., waking up to an alarm clock or a phone alarm), and others were performed only on Day 2. One week after watching the Day 2 movie, participants completed a cued-recall test. Changes that participants detected but did not remember led to proactive interference in recall, but changes that were successfully detected and remembered led to facilitation. Younger adults detected and remembered more changes than older adults, which partly explained older adults' differential memory deficit for changed activities. These findings suggest a role for episodic reminding in event perception and a potential source of age differences in event memory. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Making remembering more memorable

Memory retrieval is a cognitive operation that itself can be remembered or forgotten, with potentially important consequences. To study memory for prior remembering, we had participants first study target words (e.g., bark) alongside semantically related cue words (e.g., dog). Then, on Test 1, participants retrieved targets in response to either the study cue or a changed cue that was semantically related to a homograph of the target (e.g., birch). Finally, on Test 2, participants retrieved all targets in response to the original study cues, and participants judged whether targets were previously retrieved on Test 1. As in previous research, cue change on Test 1 rendered target retrievals less memorable, suggesting context changes harm memory for prior remembering. We hypothesised that the negative effect of context change could be ameliorated by reminding participants of the original study cues during Test 1. We had participants either retrieve (Experiments 1 and 3, Ns = 46 and 62) or view (Experiment 2, N = 118) the study cue following each target retrieval. Reminding significantly reduced the negative effect of cue change, with self-generation being especially potent. This indicates that reminding can make remembering more memorable in the face of context change.

Memory for flip-flopping: detection and recollection of political contradictions

During political campaigns, candidates often change their positions on controversial issues. Does changing positions create confusion and impair memory for a politician's current position? In 3 experiments, two political candidates held positions on controversial issues in two debates. Across the debates, their positions were repeated, changed, or held only in the second debate (control). Relative to the control condition, recall of the most recent position on issues was enhanced when change was detected and recollected, whereas recall was impaired when change was not recollected. Furthermore, examining the errors revealed that subjects were more likely to intrude a Debate 1 response than to recall a blend of the two positions, and that recollecting change decreased Debate 1 intrusions. We argue that detecting change produces a recursive representation that embeds the original position in memory along with the more recent position. Recollecting change then enhances memory for the politician's positions and their order of occurrence by accessing the recursive trace.

Testing can counteract proactive interference by integrating competing information

Testing initially learned information before presenting new information has been shown to counteract the deleterious effects of proactive interference by segregating competing sources of information. The present experiments were conducted to demonstrate that testing can also have its effects in part by integrating competing information. Variations of classic A-B, A-D paired-associate learning paradigms were employed that included two lists of word pairs and a cued-recall test. Repeated pairs appeared in both lists (A-B, A-B), control pairs appeared in List 2 only (A-B, C-D), and changed pairs appeared with the same cue in both lists but with different responses (A-B, A-D). The critical manipulation was whether pairs were tested or restudied in an interpolated phase that occurred between Lists 1 and 2. On a final cued-recall test, participants recalled List 2 responses and then indicated when they recollected that responses had earlier changed between lists. The change recollection measure indexed the extent to which competing responses were integrated during List 2. Change was recollected more often for tested than for restudied pairs. Proactive facilitation was obtained in cued recall when change was recollected, whereas proactive interference was obtained when change was not recollected. These results provide evidence that testing counteracted proactive interference in part by making List 1 responses more accessible during List 2, thus promoting integration and increasing later recollection of change. These results have theoretical implications because they show that testing can counteract proactive interference by integrating or segregating competing information.