Adult age differences in implicit and explicit memory: time course and encoding effects

Young and older adults were tested at three delays on word-stem completion or cued recall following semantic or structural word judgments. Identical three-letter stems were present at retrieval for both implicit (completion) and explicit (cued recall) tasks; only the intention to recall list words differed. The young adults outperformed the older adults on both implicit and explicit tasks at all test delays. Under some conditions, the older but not the young adults performed more poorly on cued recall than on stem completion, suggesting a possible failure to use implicitly available information to support explicit remembering. These results suggest that some forms of implicit memory decline with normal aging.     

Direct and indirect tests of memory for category exemplars in young and older adults

Young and older adults were compared on direct (cued recall) and indirect (exemplar generation) tests of memory for category members. Because category names served as cues in both tasks, amount of retrieval support was constant across tasks. Although older adults produced fewer category members in cued recall, priming of category exemplars in the generation task did not vary with age. These results suggest that age constancy in priming tasks does not depend on physical similarity between study materials and retrieval cues provided at test and point to the importance of deliberate recollection as a factor in determining the extent of age differences in memory.     

Age-related differences on a new test of temporal order memory for everyday events

We developed a new test to examine incidental temporal order memory for a self-generated sequence of tasks one might complete in everyday life. Young and older adults were given 10 cards, each listing a task one might accomplish in a typical day. Participants were asked to self-generate a “to do” list by placing the 10 cards in a sequence representing the order in which they would accomplish the tasks, but were not informed of a subsequent memory test. We assessed immediate free recall, delayed free recall, and delayed cued recall for the order of the tasks in the sequence. Older adults were significantly impaired relative to young adults on immediate free recall, delayed free recall, and delayed cued recall. Correlation analyses with standardized neuropsychological tests provide preliminary evidence for construct validity for our test, which is portable and can be rapidly administered in clinical or laboratory settings.     

Use of relational and item-specific information in remembering by older and younger adults

The applicability to older adults of predictions from the integrated memory model, that optimal memory results from concurrent availability of relational and item-specific information, was assessed. In Experiment 1, older adults (M = 69 years) encoded related or unrelated words using rating, sorting, or both tasks. Using both tasks produced better recall than either separate task. Rating facilitated recall for related items, but sorting did not facilitate unrelated items. In Experiment 2, younger (M = 20) and older (M = 74) adults sorted or rated lists comprising categories of varying sizes. Young adults' free recall conformed to predictions, but older adults again showed facilitation mainly from rating larger categories. The stronger effects for younger adults imply that specific combinations of encoding and retrieval manipulations and materials must be considered in predicting older adults' performance.     

Reflections of distraction in memory: transfer of previous distraction improves recall in younger and older adults

Three studies explored whether younger and older adults' free recall performance can benefit from prior exposure to distraction that becomes relevant in a memory task. Participants initially read stories that included distracting text. Later, they studied a list of words for free recall, with half of the list consisting of previously distracting words. When the memory task was indirect in its use of distraction (Study 1), only older adults showed transfer, with better recall of previously distracting compared with new words, which increased their recall to match that of younger adults. However, younger adults showed transfer when cued about the relevance of previous distraction both before studying the words (Study 2) and before recalling the words (Study 3) in the memory test. Results suggest that both younger and older adults encode distraction, but younger adults require explicit cueing to use their knowledge of distraction. In contrast, older adults transfer knowledge of distraction in both explicitly cued and indirect memory tasks. Results are discussed in terms of age differences in inhibition and source-constrained retrieval.     

Spatial and relational frameworks for free recall in young and older adults

Previous studies have demonstrated that older adults can use visually distinctive cues to enhance their spatial memory performance and their recall of the identities of items located in space. Other research has shown that older adults can also use relational information to enhance recall. The relationship between relational and visuospatial support for memory across the adult lifespan is complex and has been little explored. In the present study, this relationship was examined in tasks that measured free recall for item sets possessing different degrees of visuospatial and relational support for recall. It was predicted that both types of support would enhance older adult recall relative to that of the young, and that the two types of support would synergize. The results were generally consistent with these predictions. These findings show that older adults can use relatively simple relational or visuospatial support systems to enhance free recall significantly. This research was supported by Grant AGI 1605, National Institute on Aging.     

Spatial and relational frameworks for free recall in young and older adults

Previous studies have demonstrated that older adults can use visually distinctive cues to enhance their spatial memory performance and their recall of the identities of items located in space. Other research has shown that older adults can also use relational information to enhance recall. The relationship between relational and visuospatial support for memory across the adult lifespan is complex and has been little explored. In the present study, this relationship was examined in tasks that measured free recall for item sets possessing different degrees of visuospatial and relational support for recall. It was predicted that both types of support would enhance older adult recall relative to that of the young, and that the two types of support would synergize. The results were generally consistent with these predictions. These findings show that older adults can use relatively simple relational or visuospatial support systems to enhance free recall significantly. This research was supported by Grant AGI 1605, National Institute on Aging.     

Episodic memory change in late adulthood: Generalizability across samples and performance indices

Younger adults recall more information from episodic memory tasks than do older adults. Because longitudinal studies are rare and often incompatible, the extent of actual late-life memory change is not well established. We assemble two different longitudinal samples of normal older adults, each of which is tested twice at a 3-year interval, using a large battery of episodic memory indicators. Together, two-wave data from both the Victoria Longitudinal Study in Canada (n = 400) and the Kungsholmen Project in Sweden (n = 168) cover a 40-year span of adulthood, ranging from 54 to 94 years of age. Principal memory tasks include categorizable word lists, story recall, and random word lists, as well as indicators of cognitive support. Overall, an examination of performance on sets of common and complementary episodic tasks reveals that, for both samples, actual 3-year changes are modest and that, when decline occurs, it is gradual. The exception-greater decline for more supported tasks-suggests that these may be especially sensitive to late-life changes.     

Age differences in memory for prospective compared with retrospective subject-performed tasks

In two experiments, younger and older adults studied three lists of verbal phrases, each of the latter describing a simple action. One list was studied and recalled verbally; one was recalled verbally, but the actions were performed at study [retrospective SPTs (subject-performed tasks)]; and one was studied verbally and the actions were performed at test (prospective SPTs). With long lists, but not with short ones, retrospective-SPT recall exceeded verbal recall and older adults recalled fewer SPTs than did younger adults. Prospective-SPT recall did not exceed verbal recall at either list length, and in each of these prospective-SPT tests, older adults recalled fewer action phrases than did younger adults. Thus, it appears that when retrospective and prospective tasks are equated there are marked age differences that are generally consistent with the view that memory impairment in the elderly is more likely to occur in tasks that make higher attentional processing demands.     

How much and how fast: rapid processing of spoken language in later adulthood

Speech processing involves rapid decoding and construction of meaning from a transitory acoustic signal. Because older adults have been found to be slower in performing many cognitive tasks, we hypothesized that they may have difficulty in immediate recall for speech of increasing input rate. Two experiments are reported in which both older and younger participants listened to and immediately recalled sentences that were systematically varied in speech rate and number of propositions. Although recall performance of the older adults showed a disproportionate decline when speech rate was increased, older adults, as well as the younger adults, were able to recall sentences of increasing propositional densities. We also found that the tendency to recall a greater proportion of main ideas than details (the levels effect) was enhanced by increased propositional density, and depressed by increased speech rate and increased age. These results are discussed in terms of an age-related change in the rate at which information can be processed in working memory.     

Greater priming for previously distracting information in young than older adults when suppression is ruled out

The use of previously distracting information on memory tests with indirect instructions is usually age-equivalent, while young adults typically show greater explicit memory for such information. This could reflect qualitatively distinct initial processing (encoding) of distracting information by younger and older adults, but could also be caused by greater suppression of such information by younger adults on tasks with indirect instructions. In Experiment 1, young and older adults read stories containing distracting words, which they ignored, before studying a list of words containing previously distracting items for a free recall task. Half the participants were informed of the presence of previously distracting items in the study list prior to recall (direct instruction), and half were not (indirect instruction). Recall of previously distracting words was age-equivalent in the indirect condition, but young adults recalled more distracting words in the direct condition. In Experiment 2, participants performed the continuous identification with recognition task, which captures a measure of perceptual priming and recognition on each trial, and is immune to suppression. Priming and recognition of previously distracting words was greater in younger than older adults, suggesting that the young engage in more successful suppression of previously distracting information on tasks in which its relevance is not overtly signaled.     

Contributions of processing ability and knowledge to verbal memory tasks across the adult life-span

This study investigated the relationships of processing capacity and knowledge to memory measures that varied in retrieval difficulty and reliance on verbal knowledge in an adult life-span sample (N = 341). It was hypothesized that processing ability (speed and working memory) would have the strongest relationship to tasks requiring active retrieval and that knowledge (vocabulary ability) would be related to verbal fluency and cued recall, as participants relied upon verbal knowledge to retrieve category items (fluency) or develop associations (cued recall). Measurement and structural equation models were developed for the entire sample and separately for younger (aged 20-54 years, n = 168) and older (aged 55-92 years, n = 173) subgroups. In accordance with the hypotheses, processing ability was found to be most highly related to free recall, with additional significant relationships to cued recall, verbal fluency, and recognition. Knowledge was found to be significantly related only to verbal fluency and to cued recall. Moreover, knowledge was more important for older than for younger adults in mediating variance in cued recall, suggesting that older adults may use age-related increases in knowledge to partially compensate for processing declines when environmental support is available in memory tasks.     

Verbal and visuospatial short-term memory in children: Evidence for common and distinct mechanisms

This study was designed to identify whether verbal and visuospatial short-term memory performance in children is served by common or distinct mechanisms. Five- and 8-year-old children were tested on their verbal recall of spoken letter names and digits, and on their recall of tapped sequences of blocks. The performance of the children on the verbal and visuospatial serial recall tasks was largely unrelated, extending evidence for dissociable memory systems found in adults. Detailed characteristics of recall, such as serial position functions, migration patterns, and distribution of error types, were similar in the tasks requiring recall of letters and of blocks, although order errors predominated in the block but not the letter recall task for the older children. These results appear to reflect the application of common processes specialized for the extraction of serial order information from the phonological and visuospatial components of short-term memory.     

Causal attributions and strategy use in relation to memory performance differences in younger and older adults

A metacognitive hypothesis to explain age differences in adult memory is explored here–that younger and older adults differ in beliefs about memory and strategic processing. The motivational beliefs that adults make for their own memory performances were examined across tests of recall, recognition, face–name learning, and appointment-keeping. Forty-eight older and 48 younger community-living adults were required to report the factors they believed influenced their performance and the memory strategies used for each task. A final questionnaire required subjects to rank order the importance of a list of causal factors. There were significantly more younger adults as compared to older adults who attributed performance to controllable factors (i.e. strategy use), although age differences in beliefs on a more familiar memory task were smaller than on other tasks. Moreover, within age groups, attributions to controllable factors were associated with increased memory performance compared to when memory was attributed to uncontrollable factors (i.e. ability, age). Believing that memory is uncontrollable may undermine the efficient use of effort in cognition, consistent with current metacognitive theory.     

Short-term memory predictions across the lifespan: monitoring span before and after conducting a task

Our objective was to explore metamemory in short-term memory across the lifespan. Five age groups participated in this study: 3 groups of children (4–13 years old), and younger and older adults. We used a three-phase task: prediction–span–postdiction. For prediction and postdiction phases, participants reported with a Yes/No response if they could recall in order a series of images. For the span task, they had to actually recall such series. From 4 years old, children have some ability to monitor their short-term memory and are able to adjust their prediction after experiencing the task. However, accuracy still improves significantly until adolescence. Although the older adults had a lower span, they were as accurate as young adults in their evaluation, suggesting that metamemory is unimpaired for short-term memory tasks in older adults.

Highlights:

?We investigate metamemory for short-term memory tasks across the lifespan.

?We find younger children cannot accurately predict their span length.

?Older adults are accurate in predicting their span length.

?People’s metamemory accuracy was related to their short-term memory span.     

Goal-directed memory: the role of cognitive control in older adults' emotional memory

The present study revealed that older adults recruit cognitive control processes to strengthen positive and diminish negative information in memory. In Experiment 1, older adults engaged in more elaborative processing when retrieving positive memories than they did when retrieving negative memories. In Experiment 2, older adults who did well on tasks involving cognitive control were more likely than those doing poorly to favor positive pictures in memory. In Experiment 3, older adults who were distracted during memory encoding no longer favored positive over negative pictures in their later recall, revealing that older adults use cognitive resources to implement emotional goals during encoding. In contrast, younger adults showed no signs of using cognitive control to make their memories more positive, indicating that, for them, emotion regulation goals are not chronically activated.     

Memory for grocery prices in younger and older adults: the role of schematic support

The present study examined how younger and older adults remember price information. Participants studied grocery items that were priced at market value or were well above or below market value. Although younger adults displayed better recall performance for unrealistic prices than older adults, there was no age difference for realistic prices, and both groups were equally accurate at remembering the general price range of the items. The results suggest that when older adults can rely on prior knowledge and schematic support, and tasks involve naturalistic materials, memory for associative information can be as good as that of younger adults.     

A study of retrieval processes in action memory for school-aged children: the impact of recall period and difficulty on action memory

ABSTRACT

Research in action memory for adults has shown that enacted encoding is not only retrieved more frequently but is also faster in comparison to verbal encoding. The aim of this study was to investigate retrieval processes in terms of recall period and recall difficulty for different encoding conditions in school-aged children (8-, 10-, 12-, 14-years old). The participants studied verbal tasks, subject-performed tasks and experimenter-performed tasks, and received immediate and final free-recall tests. The results revealed that older children not only outperformed younger children in terms of accuracy but also outpaced them in all recall periods. Moreover, recalls of subject-performed tasks and experimenter-performed tasks were better and faster compared with verbal encoding on both types of recall test, by increasing throughout the recall periods. These results are discussed in terms of memory strategies and information processing methods. Pedagogic implications for the use of action memory in children's learning are also considered.     

Age deficits in recall under optimal study conditions

Young and older adults studied lists of words under both standard and optimal study conditions for subsequent free recall. Under optimal conditions, the participants studied each word for as long as they wished, were allowed to take notes, and were encouraged to actively use whatever strategies they thought would maximize recall. Both age groups recalled more words under optimal study conditions than under standard conditions, but the improvement was greater for the young adults. This increase in the age-related recall deficit was not due to differences in study time. The results suggest that standard laboratory memory tasks do not overestimate the memory deficits of older adults because of a failure to provide either optimal learning conditions or sufficient study time.