Dismantling the “age–prospective memory paradox”: The classic laboratory paradigm simulated in a naturalistic setting

Previous research has identified “the age–prospective memory paradox”—that adult ageing results in reliably poorer performance on laboratory-based tasks of prospective memory (PM), but improved performance on such tasks carried out in real-life settings. We hypothesized that even in their everyday environment, older adults might be worse at PM tasks that are triggered during an experimenter-generated ongoing activity. The present study used a task that captured the key features of the classic laboratory paradigm, but which was completed in a setting that met key criteria to be considered naturalistic. In their everyday setting, participants' PM was assessed, with the cue to remember occurring either (a) during their day-to-day activities, or (b) during an experimenter-generated ongoing task. The results confirmed previous naturalistic findings, in showing that older adults (n = 28) exhibited better PM than their younger counterparts (n = 65) when prompted during their everyday activities. However, older adults were also then subsequently less likely to show effective PM during experimenter-generated ongoing activity. Reproducing the paradox within a single dataset, these data indicate that older adults can effectively act on intentions during everyday activities, but have difficulty in prospective remembering during experimenter-generated ongoing tasks.     

Age‐related differences in everyday prospective memory tasks: The role of planning and personal importance

The aim of the present studies was to investigate whether age‐related improvement found in naturalistic but experimenter‐given prospective memory (PM) tasks can be generalized to real‐life intentions. In Study 1, younger, middle‐aged, and older adults generated a list of intended activities for the following week; one week later they marked the tasks that they had performed. The participants were also asked to rate the importance of each listed intention and to describe the circumstances of completion that were already known to them. We found that, compared with younger adults, older adults attributed a higher degree of importance to their intentions and had the circumstances of their completion better planned. However, the age‐related benefit in the PM performance for all listed intentions was not present for the very important and well‐planned tasks. In Study 2 we manipulated whether younger adults engaged or not in the detailed planning of when their intentions could be completed. It was demonstrated that younger adults who had to perform detailed planning completed their intended activities more often than those who did not plan for their intentions. The results support explanations of the age‐related benefit in everyday PM that highlight the role of importance and planning.     

Age benefits in everyday prospective memory: the influence of personal task importance, use of reminders and everyday stress

The present diary study examined everyday prospective memory tasks in younger and old adults and explored the role of personal task importance, use of reminders and everyday stress as possible correlates of age-related prospective memory performance in everyday life. Results revealed an age benefit in everyday prospective memory tasks. In addition, task importance was identified as a critical moderator of age-related prospective memory performance. More frequent use of reminders and lower levels of stress, however, were associated with better prospective memory performance in general but did not contribute to age-related prospective memory performance. Exploring further possible correlates of prospective memory revealed that the strategy to reprioritize initially planned intentions was associated with age benefits in everyday prospective memory. Results suggest that the age-related benefit observed in experimenter-given tasks transfers to everyday prospective memory and varies in dependence of motivational and cognitive factors. Implications for theoretical models of prospective memory and aging are discussed.     

The effect of implementation intentions on prospective memory performance across the lifespan

Differences in the amount and availability of cognitive resources may be responsible for age‐related differences in event‐based prospective memory tasks. We hypothesised that a manipulation which reduces resource requirements by enhancing automatic processing will reduce age differences. Implementation intentions are assumed to satisfy this requirement. We tested a total of 563 participants, 185 adolescents, 193 young adults and 185 older adults in order to investigate whether providing participants with implementation intention instructions would improve performance, whether any improvement would vary with age, and whether it would affect the prospective component or the retrospective component. The results showed a benefit of implementation intentions for older adults, but not for adolescents and for young adults. Separate analyses for the prospective and the retrospective components revealed that this effect was based mainly on a performance facilitation of the prospective component. These results suggest that implementation intentions provide a means to reduce age differences in prospective memory. Copyright © 2009 John Wiley & Sons, Ltd.     

Relationship of cognitive strategy use to prospective memory performance in a diverse sample of nondemented older adults with varying degrees of cognitive complaints and impairment

Although older adults typically have better performance on prospective memory (PM) tasks carried out in naturalistic settings, a paucity of research directly assesses older adults’ use of compensatory strategies on such tasks. The current study investigates external memory strategy use during performance of a clinical PM test that features both short-term (in laboratory) and long-term (out of laboratory) subtasks (i.e., the Royal Prince Alfred Prospective Memory Test – RPA-ProMem. Nondemented, community-dwelling older adults (n = 214; mean age = 80.5; 68.2% female; 39.7% non-white) with mild cognitive impairment, subjective cognitive decline, and healthy controls completed the RPA-ProMem while external strategy use was permitted and recorded. Overall, participants utilized external strategies 41% of the time on the RPA-ProMem. Increased utilization of external memory strategies was significantly associated with better PM performance. Additionally, better performance on executive functioning tasks was associated with increased use of external memory strategies. Results are discussed in relation to how memory strategy use can be enhanced to improve everyday memory ability in older adults at risk for dementia.     

The effects of age, enactment, and cue-action relatedness on memory for intentions in the Virtual Week task

ABSTRACT The current study investigated the influence of encoding modality and cue-action relatedness on prospective memory (PM) performance in young and older adults using a modified version of the Virtual Week task. Participants encoded regular and irregular intentions either verbally or by physically performing the action during encoding. For half of the intentions there was a close semantic relation between the retrieval cue and the intended action, while for the remaining intentions the cue and action were semantically unrelated. For irregular tasks, both age groups showed superior PM for related intentions compared to unrelated intentions in both encoding conditions. While older adults retrieved fewer irregular intentions than young adults after verbal encoding, there was no age difference following enactment. Possible mechanisms of enactment and relatedness effects are discussed in the context of current theories of event-based PM.     

The effects of age,enactment, and cue-action relatedness on memory for intentions in the Virtual Week task

ABSTRACT

The current study investigated the influence of encoding modality and cue-action relatedness on prospective memory (PM) performance in young and older adults using a modified version of the Virtual Week task. Participants encoded regular and irregular intentions either verbally or by physically performing the action during encoding. For half of the intentions there was a close semantic relation between the retrieval cue and the intended action, while for the remaining intentions the cue and action were semantically unrelated. For irregular tasks, both age groups showed superior PM for related intentions compared to unrelated intentions in both encoding conditions. While older adults retrieved fewer irregular intentions than young adults after verbal encoding, there was no age difference following enactment. Possible mechanisms of enactment and relatedness effects are discussed in the context of current theories of event-based PM.     

Virtual Week: Validity and psychometric properties of a Polish adaptation

IntroductionProspective memory (PM) refers to memory for future intentions and it is essential for safe and independent living. This paper focuses on Virtual Week (VW), a measure that was developed to closely represent everyday PM tasks in an English language setting in North America and Australia.ObjectivesThe main objective of the present study is to offer the results of a Polish adaptation of VW and present the validity and psychometric properties of the adapted version.MethodThe Spearman-Brown split-half reliability coefficients and Cronbach's alphas were estimated in 77 young adults and 83 healthy older adults. To confirm the validity of the Polish VW, we analyzed whether it is sensitive to the pattern of PM deficits in the healthy elderly that is consistent with mechanisms underlying PM performance as well as theories of normal aging.ResultsThe Polish VW was found to have strong psychometric properties and be sensitive to theory- and data-based effects on PM.ConclusionThe findings strongly encourage the use of VW for experimental purposes in healthy older adults. They provide further evidence that VW has a universal appeal and may be used in non-English speaking European samples.     

The age prospective memory paradox within the same sample in time-based and event-based tasks

The present research investigated the age prospective memory (PM) paradox by testing the performance of the same participants on laboratory and naturalistic PM tasks. Younger, middle-aged, and older adults performed three tasks (time-based, event-based with focal cue, and event-based with nonfocal cue); first in the laboratory, then in the context of their everyday lives. Additionally, the social importance of PM tasks was manipulated in the laboratory. As expected, age-dependent declines on the laboratory tasks were reversed in the naturalistic tasks. Middle-aged adults performed as well as younger adults in the laboratory and as well as the elderly outside of the laboratory. When the social importance of laboratory tasks was stressed, the performance of younger adults fell. In addition, older adults showed higher self-reported commitment to the naturalistic tasks than both younger and middle-aged adults. Findings are discussed in the context of possible explanations for the age PM paradox.     

Working memory training and transfer in older adults

There has been a great deal of interest, both privately and commercially, in using working memory training exercises to improve general cognitive function. However, many of the laboratory findings for older adults, a group in which this training is of utmost interest, are discouraging due to the lack of transfer to other tasks and skills. Importantly, improvements in everyday functioning remain largely unexamined in relation to WM training. We trained working memory in older adults using a task that encourages transfer in young adults (Chein & Morrison, 2010). We tested transfer to measures of working memory (e.g., Reading Span), everyday cognitive functioning [the Test of Everyday Attention (TEA) and the California Verbal Learning Test (CVLT)], and other tasks of interest. Relative to controls, trained participants showed transfer improvements in Reading Span and the number of repetitions on the CVLT. Training group participants were also significantly more likely to self-report improvements in everyday attention. Our findings support the use of ecological tasks as a measure of transfer in an older adult population.     

Executive functioning and prospective memory in young children

The current study examined the role of executive functioning (EF) in children's prospective memory (PM) by assessing the effect of delay and number of intentions to-be-remembered on PM, as well as relations between PM and EF. Ninety-six 4-, 5-, and 6-year-olds completed a PM task and two executive function tasks. The PM task required children to interrupt an ongoing card game to perform one action (single intention) or two actions (dual intention) with target cards after a short delay (1 min) or a long delay (5 min). There was no main effect of number of intentions or delay on the PM task. However, performance improved with age, and age and delay interacted such that 4-year-olds’ performance remained the same after a long delay whereas 5-year-olds’ performance improved after a long delay. We suggest that the age by delay interaction is a product of age differences in cognitive monitoring. Working memory but not inhibitory control predicted PM with age controlled. We argue that an executive function framework permits an integrative understanding of many processes involved in young children's prospective memory.     

The intention‐superiority effect for naturally occurring activities: The role of intention accessibility in everyday prospective remembering in young and older adults

This study examined age differences in the accessibility of a single pool of naturally occurring intentions both before and after completion. Following Maylor, Darby, and Della Sala (2000), accessibility was measured in terms of the number of activities generated in a 4‐minute activity fluency task. Each participant undertook two such tasks. A prospective task in which they generated activities intended for completion during the following week and a retrospective task, 1 week later, in which they generated activities carried out over the previous week. In a partial replication of Maylor et al.'s findings, young, but not healthy older, adults generated more to‐be‐completed intentions than completed ones, demonstrating an intention‐superiority effect (ISE) for everyday activities. The absence of an ISE for older adults appeared to reflect the reduced accessibility of intentions prior to completion, rather than the impaired inhibition of fulfilled intentions. Moreover, both groups showed greater inaccessibility of completed than intended activities, thus demonstrating an intention‐completion effect for naturally occurring intentions that is preserved in healthy ageing (cf. Marsh, Hicks, & Bink, 1998). Despite showing a reduced accessibility of intended activities, older adults reported having completed a greater proportion of their intentions during the week than young adults. Moreover, there was a correlation between the ability to access intentions and the proportion of intentions completed only for young adults. These observations suggest that older adults' everyday prospective memory performance may be relatively less dependent on intention accessibility and more dependent on other factors. While there was no age difference in the reported use and effectiveness of external retrieval aids, older adults demonstrated a greater level of temporal organization in the production of their intentions in the fluency task. This is consistent with the possibility that older adults may have more structured daily lives and may be able to use information about the sequence of ongoing events to support superior everyday prospective remembering.     

Aging affects word-stem completion and recognition but not category generation

In this study, we investigated the effect of aging on two implicit memory tasks, word-stem completion and category generation, and on explicit recognition. We compared the performance of young and older adults on these implicit memory tasks with those of explicit recognition. We expected better performance of young than older adults in the explicit memory task and similar priming in both implicit memory tasks. The results showed that young adults performed better than older adults in the recognition task. Moreover, both age groups showed priming in the implicit memory tasks, although priming was greater in young adults compared to older adults in the word-stem completion memory task, whereas both age groups showed similar levels of priming in the category generation task. The present results showed dissociations as a function of age not only between the explicit and the implicit tasks but also between the implicit tasks.     

Susceptibility to retroactive interference: The effect of context as a function of age and cognition

Previous studies have shown that contextual cues improve memory performance and reduce interference in younger adults. However, it is not clear whether middle-aged and older adults can also benefit from contextual cues, or if this ability diminishes with ageing and cognitive decline. In order to test this question, we tested 69 middle-aged adults (aged 30–50 years) and 65 older adults (aged 65–85). Participants completed a retroactive interference paradigm with or without contextual cues. Cognitive functioning of older adults was assessed using the Montreal Cognitive Assessment, which is a sensitive and highly validated tool to detect cognitive decline in older age. The results showed that while middle-aged adults were able to benefit from context to improve recognition and reduce interference, older adults were not able to benefit from it. However, when we compared older adults with lower (<26) and higher (≥26) scores on the Montreal Cognitive Assessment, we found that older adults with high cognitive functioning could benefit from context advantage at retrieval to improve recognition compared to those with lower cognitive functioning. Yet, similar to older adults with lower cognitive functioning, they could not benefit from context advantage at encoding and hence were still susceptible to interference.     

Ageing and the self-reference effect in memory

The present study investigates potential age differences in the self-reference effect. Young and older adults incidentally encoded adjectives by deciding whether the adjective described them, described another person (Experiments 1 & 2), was a trait they found desirable (Experiment 3), or was presented in upper case. Like young adults, older adults exhibited superior recognition for self-referenced items relative to the items encoded with the alternate orienting tasks, but self-referencing did not restore their memory to the level of young adults. Furthermore, the self-reference effect was more limited for older adults. Amount of cognitive resource influenced how much older adults benefit from self-referencing, and older adults appeared to extend the strategy less flexibly than young adults. Self-referencing improves older adults’ memory, but its benefits are circumscribed despite the social and personally relevant nature of the task.     

Cognitive functioning in healthy older adults aged 64-81: a cohort study into the effects of age, sex, and education

The objective of this study was to determine a possible differential effect of age, education, and sex on cognitive speed, verbal memory, executive functioning, and verbal fluency in healthy older adults. A group of 578 healthy participants in the age range of 64-81 was recruited from a large population study of healthy adults (Maastricht Aging Study). Even in healthy individuals in this restricted age range, there is a clear, age-related decrease in performance on executive functioning, verbal fluency, verbal memory, and cognitive speed tasks. The capacity to inhibit information is affected most. Education had a substantial effect on cognitive functioning: participants with a middle or high level of education performed better on cognitive tests than did participants with a low level of education. Women performed better than men on verbal memory tasks. Therefore, education and sex must be taken into account when examining an older individual's cognitive performance.     

Ageing and the self-reference effect in memory

The present study investigates potential age differences in the self-reference effect. Young and older adults incidentally encoded adjectives by deciding whether the adjective described them, described another person (Experiments 1 & 2), was a trait they found desirable (Experiment 3), or was presented in upper case. Like young adults, older adults exhibited superior recognition for self-referenced items relative to the items encoded with the alternate orienting tasks, but self-referencing did not restore their memory to the level of young adults. Furthermore, the self-reference effect was more limited for older adults. Amount of cognitive resource influenced how much older adults benefit from self-referencing, and older adults appeared to extend the strategy less flexibly than young adults. Self-referencing improves older adults' memory, but its benefits are circumscribed despite the social and personally relevant nature of the task.     

Cognitively impaired older adults exhibit comparable difficulties on naturalistic and laboratory prospective memory tasks

Prospective memory, or remembering future intentions, is critical for independent living for all ages, but especially older adults. Previous laboratory research has found that cognitively impaired older adults may have particular difficulties with prospective memory, but previous studies have not examined whether these difficulties occur in everyday life. In normal ageing, a dissociation between settings has been observed, with older adults selectively impaired in laboratory (but not naturalistic) contexts. Consequently, in the present study 15 cognitively impaired older adults were compared to demographically matched controls on laboratory and naturalistic measures of prospective memory. The results indicated that the cognitively impaired group performed more poorly on both measures, with the magnitude of the deficit comparable across setting. These results indicate that for older adults who present with cognitive impairment prospective memory deficits observed in laboratory settings may be a valid indicator of difficulties experienced executing delayed intentions in everyday life. Copyright © 2008 John Wiley & Sons, Ltd.     

Cognitive Performance and the Role of Control Beliefs in Midlife

Midlife has been touted as being a time of peak performance in many different areas of functioning. In the present study, we investigated whether this was true for cognitive functioning on tasks assessing speed, reasoning, short-term memory, and vocabulary. We also explored the extent to which levels of cognitive functioning could be attributed to individual differences in general control beliefs. Middle-aged adults showed little or no cognitive declines on speed, reasoning, and short-term memory measures relative to the young and outperformed the young on vocabulary. Relative to the elderly, middle-aged adults scored higher on all tasks except vocabulary, for which there were no differences. Adults in midlife, on the other hand, had lower scores on measures of general control beliefs compared to younger adults. Thus, although midlife is a time of high cognitive functioning, it is also a time of lower beliefs about control. To investigate the relationship between control beliefs and cognitive performance, we used structural equation modeling. The models showed that for adults in midlife, control beliefs were predictive of performance but only for the reasoning task after background variables were considered. Specifically, high levels of control beliefs were associated with better cognitive performance. More work is needed to identify mediational processes linking control beliefs and cognitive performance for various age groups and to determine whether some cognitive processes are more controllable than others.     

Influence of articulation rate on two memory tasks in young and older adults

This study investigated the relation between phonological loop functioning and age. Phonological loop is a time-based subsystem of the Working Memory Model of Baddeley and Wilson, which uses rehearsal of information as an active process to avoid phonological decay. Performance differences were examined between young and older adults in two speech-based memory tasks, such as the immediate serial recall of words and the Digit Ordering Task. Analysis showed that performance on both tasks was lower for the older group. Articulation rate was also measured to test the hypothesis that the impairment of some cognitive functions in adults can be associated to their slowness or the greater time needed by older adults for the rehearsal process. A significant negative correlation was found for articulation rate with age. When the effect of articulation rate on Serial Recall and Digit Ordering Tasks was partialled out, the difference between the two groups was eliminated.