The effects of pure pair repetition on younger and older adults' associative memory

Although aging causes relatively minor impairment in recognition memory for components, older adults' ability to remember associations between components is typically significantly compromised, relative to that of younger adults. This pattern could be associated with older adults' relatively intact familiarity, which helps preserve component memory, coupled with a marked decline in recollection, which leads to a decline in associative memory. The purpose of the current study is to explore possible methods that allow older adults to rely on pair familiarity in order to improve their associative memory performance. Participants in 2 experiments were repeatedly presented with either single items or pairings of items prior to a study list so that the items and the pairs were already familiar during the study phase. Pure pair repetition (the effects of pair repetition after the effects of item repetition are taken into account) increased associative memory for older and younger adults. Findings based on remember and know judgments suggest that familiarity but not recollection is involved in mediating the repetition effect.     

Effects of repetition on associative recognition in young and older adults: item and associative strengthening

Young and older adults studied word pairs and later discriminated studied pairs from various types of foils including recombined word-pairs and foil pairs containing one or two previously unstudied words. We manipulated how many times a specific word pair was repeated (1 or 5) and how many different words were associated with a given word (1 or 5) to tease apart the effects of item familiarity from recollection of the association. Rather than making simple old/new judgments, subjects chose one of five responses: (a) Old-Old (original), (b) Old-Old (rearranged), (c) Old-New, (d) New-Old, (e) New-New. Veridical recollection was impaired in old age in all memory conditions. There was evidence for a higher rate of false recollection of rearranged pairs following exact repetition of study pairs in older but not younger adults. In contrast, older adults were not more susceptible to interference than young adults when one or both words of the pair had multiple competing associates. Older adults were just as able as young adults to use item familiarity to recognize which word of a foil was old. This pattern suggests that recollection problems in advanced age are because of a deficit in older adults' formation or retrieval of new associations in memory. A modeling simulation provided good fits to these data and offers a mechanistic explanation based on an age-related reduction of working memory.     

Age-related differences in brain electrical activity during extended continuous face recognition in younger children, older children and adults

To examine the development of recognition memory in primary-school children, 36 healthy younger children (8-9 years old) and 36 healthy older children (11-12 years old) participated in an ERP study with an extended continuous face recognition task (Study 1). Each face of a series of 30 faces was shown randomly six times interspersed with distracter faces. The children were required to make old vs. new decisions. Older children responded faster than younger children, but younger children exhibited a steeper decrease in latencies across the five repetitions. Older children exhibited better accuracy for new faces, but there were no age differences in recognition accuracy for repeated faces. For the N2, N400 and late positive complex (LPC), we analyzed the old/new effects (repetition 1 vs. new presentation) and the extended repetition effects (repetitions 1 through 5). Compared to older children, younger children exhibited larger frontocentral N2 and N400 old/new effects. For extended face repetitions, negativity of the N2 and N400 decreased in a linear fashion in both age groups. For the LPC, an ERP component thought to reflect recollection, no significant old/new or extended repetition effects were found. Employing the same face recognition paradigm in 20 adults (Study 2), we found a significant N400 old/new effect at lateral frontal sites and a significant LPC repetition effect at parietal sites, with LPC amplitudes increasing linearly with the number of repetitions. This study clearly demonstrates differential developmental courses for the N400 and LPC pertaining to recognition memory for faces. It is concluded that face recognition in children is mediated by early and probably more automatic than conscious recognition processes. In adults, the LPC extended repetition effect indicates that adult face recognition memory is related to a conscious and graded recollection process rather than to an automatic recognition process.     

Effects of age and divided attention on memory components derived for the category exemplar generation task

Age differences in memory performances on a conceptually driven task, the category exemplar generation (CEG) test, were investigated. Thirty-six younger adults and 36 healthy older adults studied word lists in full and divided attention conditions. Recall was tested with category names. The process-dissociation procedure was used to derive estimates of controlled and automatic memory. Old-old adults (70-84 years) exhibited poorer conscious recollection than both younger (18-24) and young-old adults (59-69). In contrast, no age differences were found in estimates of automatic memory. For the younger and older adults, the divided encoding manipulation reduced both the consciously controlled and automatic estimates of memory. The results suggest that the few prior findings of age deficits in priming on the CEG may have been an artifact of contamination from conscious retrieval processes. They also indicate that the opportunity for greater semantic processing enhances the conceptual priming of both younger and older adults.     

Effects of Age and Divided Attention on Memory Components Derived for the Category Exemplar Generation Task

ABSTRACT

Age differences in memory performances on a conceptually driven task, the category exemplar generation (CEG) test, were investigated. Thirty-six younger adults and 36 healthy older adults studied word lists in full and divided attention conditions. Recall was tested with category names. The process-dissociation procedure was used to derive estimates of controlled and automatic memory. Old-old adults (70–84 years) exhibited poorer conscious recollection than both younger (18–24) and young-old adults (59–69). In contrast, no age differences were found in estimates of automatic memory. For the younger and older adults, the divided encoding manipulation reduced both the consciously controlled and automatic estimates of memory. The results suggest that the few prior findings of age deficits in priming on the CEG may have been an artifact of contamination from conscious retrieval processes. They also indicate that the opportunity for greater semantic processing enhances the conceptual priming of both younger and older adults.     

How does encoding context affect memory in younger and older adults?

How does encoding context affect memory? Participants studied visually presented words viewed concurrently with a rich (intact face) or weak (scrambled face) image as context and subsequently made "Remember", "Know", or "New" judgements to words presented alone. In Experiment 1a, younger, but not older, adults showed higher recollection accuracy to words from rich- than from weak-context encoding trials. The age-related deficit in recollection occurred, in Experiment 1b, even when encoding and retrieval time was doubled in older adults, suggesting that insufficient processing time cannot account for this age-related deficit. In Experiment 1c, dividing attention in young, during encoding, reduced overall memory, though the recollection boost from rich encoding contexts remained, suggesting that reduced attention resources cannot explain this age-related deficit. Experiment 2 showed that an own-age bias, to face images as context, could not explain the age-related differences either. Results suggest that age deficits in recollection stem from a lack of spontaneous binding, or elaboration, of context to target information during encoding.     

Effects of repetition on age differences in associative recognition

The study reported here examined the effect of repetition on age differences in associative recognition using a paradigm designed to encourage recollection at test. Young and older adults studied lists of unrelated word pairs presented one, two, four, or eight times. Test lists contained old (intact) pairs, pairs consisting of old words that had been studied with other partners (rearranged lures), and pairs consisting of two unstudied words (new lures). Participants gave old/new responses and then indicated whether their responses were based on details that they could recollect or on familiarity. Older adults exhibited an ironic effect of repetition—an increase in false alarms on rearranged lures with more study opportunities—whereas young adults did not. Older adults also claimed to recall details of the study episode for rearranged lures whose constituent words were presented more frequently, but this was not true for young adults. Although both young and older adults said that they based correct rejections of rearranged lures on memory for details of the study episode, this effect was stronger for young adults. The observed age differences are consistent with older adults having reduced use of recollection in associative recognition tasks.     

Flexible remembering

Although highly specific memory is critical in many contexts, the ability to recall knowledge in a more abstract or “gist-based” manner is crucial in allowing transfer of learning to new situations and to complex forms of thought such as using analogies and drawing inferences based on the classification of events and objects. Yet it is unknown whether we can flexibly and intentionally alternate on demand between recollection of gist and recollection of detail, particularly for events from a single context. In a randomly cued test of item-specific versus category-based recognition, younger—and to a lesser extent, older—adults demonstrated such flexible remembering. Gist control was higher in younger than in older adults, and in older adults it correlated with measures of frontal function.     

Cognitive mechanisms of false facial recognition in older adults

Older adults show elevated false alarm rates on recognition memory tests involving faces in comparison to younger adults. It has been proposed that this age-related increase in false facial recognition reflects a deficit in recollection and a corresponding increase in the use of familiarity when making memory decisions. To test this hypothesis, we examined the performance of 40 older adults and 40 younger adults on a face recognition memory paradigm involving three different types of lures with varying levels of familiarity. A robust age effect was found, with older adults demonstrating a markedly heightened false alarm rate in comparison to younger adults for "familiarized lures" that were exact repetitions of faces encountered earlier in the experiment, but outside the study list, and therefore required accurate recollection of contextual information to reject. By contrast, there were no age differences in false alarms to "conjunction lures" that recombined parts of study list faces, or to entirely new faces. Overall, the pattern of false recognition errors observed in older adults was consistent with excessive reliance on a familiarity-based response strategy. Specifically, in the absence of recollection older adults appeared to base their memory decisions on item familiarity, as evidenced by a linear increase in false alarm rates with increasing familiarity of the lures. These findings support the notion that automatic memory processes such as familiarity remain invariant with age, while more controlled memory processes such as recollection show age-related decline.     

情绪影响错误记忆认知机制的年龄差异

以情绪性的类别图片为实验材料,使用改进后的简化联合再认范式,结合多项式加工树建模的统计手段,对28名老年人(67.95±4.70岁)和29名年轻人(22.60±2.74岁)情绪错误记忆的产生机制进行考察。结果发现,在行为层面,消极情绪增加年轻人和老年人的错误"记得",而积极情绪只增加老年人的错误"记得",老年人错误记忆的积极效应体现在更多地报告自己生动鲜明地"记得"未曾发生过的积极事件。在认知机制层面,虚假回想是导致老年人错误记忆出现积极效应的关键认知过程。相比年轻人,积极情绪会独特地增加老年人的虚假回想,进而增加错误"记得"的发生概率。     

The persistence of inferences in memory for younger and older adults: Remembering facts and believing inferences

Research shows that younger adults have difficulty forgetting inferences that they make after reading a passage, even if the information that the inferences are based on is later shown to be untrue. The present study examined the effects of these inferences on memory in the lab and tested whether older adults, like younger adults, are influenced by the lingering effects of false inferences. In addition, this study examined the nature of these inferences, by examining younger and older adults’ subjective experiences and confidence associated with factual recall and incorrect inference recall. The results showed that younger and older adults were equally susceptible to the continued influence of inferences. Both younger and older adults tended to remember facts from the stories but to believe their inferences, although confidence judgments did not differ for facts and inferences.     

How does encoding context affect memory in younger and older adults?

How does encoding context affect memory? Participants studied visually presented words viewed concurrently with a rich (intact face) or weak (scrambled face) image as context and subsequently made “Remember”, “Know”, or “New” judgements to words presented alone. In Experiment 1a, younger, but not older, adults showed higher recollection accuracy to words from rich- than from weak-context encoding trials. The age-related deficit in recollection occurred, in Experiment 1b, even when encoding and retrieval time was doubled in older adults, suggesting that insufficient processing time cannot account for this age-related deficit. In Experiment 1c, dividing attention in young, during encoding, reduced overall memory, though the recollection boost from rich encoding contexts remained, suggesting that reduced attention resources cannot explain this age-related deficit. Experiment 2 showed that an own-age bias, to face images as context, could not explain the age-related differences either. Results suggest that age deficits in recollection stem from a lack of spontaneous binding, or elaboration, of context to target information during encoding.     

Mediators of age-related differences in recollective experience in recognition memory

This study examined states of awareness with the Remember/Know paradigm during verbal recognition memory in young and old adults. Following the presentation of a word list, subjects undertook a recognition test and indicated whether they could consciously recollect its prior occurrence (R) or recognize it on some other basis, without conscious recollection (K). In this individual-difference approach we also incorporated various processing-speed and working-memory measures to study the link between aging, states of awareness and processing resources. The results revealed that, compared to younger adults, older adults exhibited a decline in the amount of R responses during the recognition test whereas the amount of K responses did not change. Structural equation modeling indicated that a slower processing speed associated with a limited working-memory capacity is a key to explaining age-related variance in conscious recollection. The findings offer further support for the distinction between remembering and knowing and for the processing-resources hypothesis of aging.     

Older adults show a self-reference effect for narrative information

The self-reference effect (SRE), enhanced memory for information encoded through self-related processing, has been established in younger and older adults using single trait adjective words. We sought to examine the generality of this phenomenon by studying narrative information in these populations. Additionally, we investigated retrieval experience at recognition and whether valence of stimuli influences memory differently in young and older adults. Participants encoded trait adjectives and narratives in self-reference, semantic, or structural processing conditions, followed by tests of recall and recognition. Experiment 1 revealed an SRE for trait adjective recognition and narrative cued recall in both age groups, although the existence of an SRE for narrative recognition was unclear due to ceiling effects. Experiment 2 revealed an SRE on an adapted test of narrative recognition. Self-referential encoding was shown to enhance recollection for both trait adjectives and narrative material in Experiment 1, whereas similar estimates of recollection for self-reference and semantic conditions were found in Experiment 2. Valence effects were inconsistent but generally similar in young and older adults when they were found. Results demonstrate that the self-reference technique extends to narrative information in young and older adults and may provide a valuable intervention tool for those experiencing age-related memory decline.     

Age-related differences in memory after attending to distinctiveness or similarity during learning

Episodic memory is vulnerable to age-related change, with older adults demonstrating both impairments in retrieving contextual details and susceptibility to interference among similar events. Such impairments may be due in part to an age-related decline in the ability to encode distinct memory representations. Recent research has examined how manipulating stimulus properties to emphasize distinctiveness can reduce age-related deficits in memory. However, few studies have addressed whether learning strategies that differentially encourage distinctiveness processing attenuate age-related differences in episodic memory. In the present study, participants engaged in two incidental encoding tasks emphasizing either distinctiveness or similarity processing. Results demonstrated higher rates of recollection for stimuli studied under the distinctiveness task than the similarity task in younger but not older adults. These findings suggest a declining capacity for distinctiveness processing to benefit memory in older adults, and raise the possibility that strategies that enhance gist-based encoding may attenuate age-related memory deficits.     

Self-referencing enhances recollection in both young and older adults

Processing information in relation to the self enhances subsequent item recognition in both young and older adults and further enhances recollection at least in the young. Because older adults experience recollection memory deficits, it is unknown whether self-referencing improves recollection in older adults. We examined recollection benefits from self-referential encoding in older and younger adults and further examined the quality and quantity of episodic details facilitated by self-referencing. We further investigated the influence of valence on recollection, given prior findings of age group differences in emotional memory (i.e., “positivity effects”). Across the two experiments, young and older adults processed positive and negative adjectives either for self-relevance or for semantic meaning. We found that self-referencing, relative to semantic encoding, increased recollection memory in both age groups. In Experiment 1, both groups remembered proportionally more negative than positive items when adjectives were processed semantically; however, when adjectives were processed self-referentially, both groups exhibited evidence of better recollection for the positive items, inconsistent with a positivity effect in aging. In Experiment 2, both groups reported more episodic details associated with recollected items, as measured by a memory characteristic questionnaire, for the self-reference relative to the semantic condition. Overall, these data suggest that self-referencing leads to detail-rich memory representations reflected in higher rates of recollection across age.     

Aging, source memory, and misrecollections

The authors propose an illusory recollection account of why cognitive aging is associated with episodic memory deficits. After listening to statements presented by either a female or a male speaker, older adults were prone to misrecollecting past events. The authors' illusory recollection account is instantiated in a new illusory recollection signal detection model that provides a better fit of older adults' data than does the standard signal detection model. They observed that age-related differences in source memory (as measured by source d' scores) virtually disappear after accounting for the occurrence of illusory recollections. These data suggest that age-related source memory impairments are not due to older adults' remembering less diagnostic source information and having to guess more. Instead, older adults appear to misremember past events more often than younger adults.     

Dual-process models of associative recognition in young and older adults: evidence from receiver operating characteristics

In 3 experiments, young and older adults studied lists of unrelated word pairs and were given confidence-rated item and associative recognition tests. Several different models of recognition were fit to the confidence-rating data using techniques described by S. Macho (2002, 2004). Concordant with previous findings, item recognition data were best fit by an unequal-variance signal detection theory model for both young and older adults. For both age groups, associative recognition performance was best explained by models incorporating both recollection and familiarity components. Examination of parameter estimates supported the conclusion that recollection is reduced in old age, but inferences about age differences in familiarity were highly model dependent. Implications for dual-process models of memory in old age are discussed.     

Repeated study of items with and without repeated context: aging effects on memory discriminability

Presenting items multiple times during encoding is a common way to enhance recognition accuracy. Under such conditions, older adults often show an increase in false recognition that counteracts benefits of repeated study. Using a false-memory paradigm with related study items and related lures, we tested whether repetition within the same encoding task or repetition across two different encoding tasks would be more beneficial to older adults’ memory discriminability. Results showed that, compared to items not repeated at study, items repeated in the same context and items repeated across different contexts showed improvements in memory discriminability in both young and older adults. This improvement was primarily reflected in improved recollection responses for both age groups across both repeat study conditions, as compared to no repetition. Importantly, the results demonstrated that repetition can be used to successfully mitigate age-related deficits by increasing memory discriminability and without incurring a cost of false recognition specific to any one age group.     

Electrophysiological evidence for late maturation of strategic episodic retrieval processes

Improvement in source memory performance throughout development is thought to be mediated by strategic processes that facilitate the retrieval of task-relevant information. Using event-related potentials (ERPs), we examined developmental changes in these processes during adolescence. Adolescents (13-14 years) and adults (19-29 years) completed a memory exclusion task which required the discrimination between words studied in one color ('targets') and words studied in the alternative color ('non-targets') under two conditions that put different demands on strategic control. Memory accuracy improved with age and also increased with decreasing control demands in both age groups. The parietal old/new effect, an ERP correlate of recollection, was reliable for targets across conditions in both age groups. By contrast, ERP correlates of non-target recollection were present in adolescents across conditions but not in adults. This suggests that adults implemented a strategy to prioritize recollection of target information with greater success than adolescents regardless of control demands, presumably reflecting maturational differences in cognitive control. In support of this view, the ERP amplitude difference between targets and non-targets was positively correlated with a measure of working memory capacity (WMC) in adults but not in adolescents. A further age-related difference was that ERP correlates of post-retrieval processing, including late right-frontal old/new effects and late posterior negativities, were observed in adults only. Together, our data suggest protracted maturation in the strategic processes that underlie selective recollection and post-retrieval control.