Prospective Memory Task Research Articles

Assessing prospective memory in children using the Memory for Intentions Screening Test for Youth (MISTY)

Objective Prospective memory (PM) is defined as the ability to remember to complete an intention in the future. The first aim of this study was to address the need for clinically useful measures of PM in children, by assessing the psychometric properties of a new measure of PM in children and adolescents, the Memory for Intentions Screening Test for Youth (MISTY). The second aim was to assess the relationship between prospective memory and age, particularly the relationships between age and the impact of different PM task demands. The third aim was to examine children’s performance on different aspects of PM, such as time-based versus event-based cues. Method One-hundred twenty-four children between the ages of 4 and 15 were given the MISTY. Results Analyses revealed good internal consistency among the eight individual MISTY trials and among the six MISTY subscales which included two different cue types (event-based and time-based), two different time delays (2 minutes and 10 minutes), and two different response types (action and verbal). Results also revealed good split-half and inter-rater reliability. Findings highlighted significant correlations between age and the MISTY total score and all subscales, consistent with PM lifespan research. On the MISTY, children overall performed better on event-based cues than on time-based cues, and on shorter time delays than longer ones; there was no effect of response type (i.e. action vs. verbal response). Conclusions The MISTY is a promising instrument with sound psychometric properties that could be useful in both clinical and research settings. Additionally, this study highlights the age-related process of PM development in children.

Increasing Extrinsic Motivation Improves Time-Based Prospective Memory in Adults with Autism: Relations with Executive Functioning and Mentalizing

Time-based prospective memory (PM) is diminished under various task demands in individuals with autism spectrum disorder (ASD). However, it is still unclear what underpins their impairment or how it could be remediated. This study explored whether instructions to prioritise one element of a PM task over another improved performance in adults with ASD (compared to a group of matched neurotypical adults), and how that is related to cognitive abilities. Results indicated that importance instructions significantly improved the PM performance of participants with ASD. Moreover, the extent of the benefit was associated significantly with objectively-measured executive set-shifting ability and self-reported inhibitory control ability (the poorer the set-shifting/inhibitory control, the greater the benefit). Implications for future research and clinical practice are discussed.

Prospective memory monitoring and aftereffects of deactivated intentions across the lifespan

The purpose of this study was to compare, across the lifespan, different costs that can occur in a prospective memory task. Specifically, we were interested in investigating the costs of responding to both activated (i.e., monitoring costs) and deactivated intentions (i.e., aftereffects). In two experiments, children, younger, and older adults performed an event-based prospective memory task consisting of four blocks (a baseline block, a prospective memory block without the occurrence of prospective memory cues, a prospective memory block with the occurrence of prospective memory cues, and a deactivation block in which unexpected no-more-relevant prospective memory cues occurred). The results revealed that monitoring costs and aftereffects were present in all age groups. Although children engaged in monitoring, their prospective memory performance was lower than for young and older adults. Moreover, aftereffects of responding to deactivated intentions were more pronounced in children and older adults. In Experiment 2, we were interested in examining whether these costs would be modulated by the type of prospective memory cues (semantic vs. perceptual). In fact, aftereffects were modulated by cue type with semantic cues producing higher costs than perceptual cues. These outcomes shed light on the different sources and the extent of cognitive costs resulting from responding to activated and deactivated intentions across the lifespan.

Cognitive control and capacity for prospective memory in complex dynamic environments.

Performing deferred actions in the future relies upon Prospective Memory (PM). Often, PM demands arise in complex dynamic tasks. Not only can PM be challenging in such environments, the processes required for PM may affect the performance of other tasks. To adapt to PM demands in such environments, humans may use a range of strategies, including flexible allocation of cognitive resources and cognitive control mechanisms. We sought to understand such mechanisms by using the Prospective Memory Decision Control (Strickland, Loft, Remington, & Heathcote, 2018) model to provide a comprehensive, quantitative account of dual task performance in a complex dynamic environment (a simulated air traffic control conflict detection task). We found that PM demands encouraged proactive control over ongoing task decisions, but that this control was reduced at high time pressure to facilitate fast responding. We found reactive inhibitory control over ongoing task processes when PM targets were encountered, and that time pressure and PM demand both affect the attentional system, increasing the amount of cognitive resources available. However, as demands exceeded the capacity limit of the cognitive system, resources were reallocated (shared) between the ongoing and PM tasks. As the ongoing task used more resources to compensate for additional time pressure demands, it drained resources that would have otherwise been available for PM task processing. This study provides the first detailed quantitative understanding of how attentional resources and cognitive control mechanisms support PM and ongoing task performance in complex dynamic environments. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

An Effect of Chronic Stress on Prospective Memory via Alteration of Resting-State Hippocampal Subregion Functional Connectivity

The alteration of hippocampal function by chronic stress impairs higher order cognitive functions such as prospective memory (PM). However, how chronic stress affects hippocampal subregions related to PM remains largely unknown. In this study, the altered functional network of hippocampal subregions related to PM in chronic stress was explored. College students (N = 21) completed PM tasks and resting-state functional magnetic resonance imaging scans one month prior to (baseline) and during the final examination week (chronic stress). Hippocampal subregions’ seed-based functional connectivity (FC) and PM were compared between baseline and chronic stress. PM performance declined in chronic stress. The FC of the cornu ammonis 2, 3 and dentate gyrus (CA23DG) with the bilateral caudate and precuneus was increased in chronic stress, while the FC of the subicular complex (SUBC) with the left middle frontal gyrus, the left inferior parietal gyrus and the right supramarginal gyrus was decreased. There was a negative correlation between PM performance and the FC of hippocampal subregions. We found chronic stress impairs PM by decreasing the FC of SUBC and increasing the FC of CA23DG. These findings suggest functional changes in hippocampal subregion networks as a mechanism underlying the impairment of PM in chronic stress.

The effect of implementation intentions on prospective memory performance in patients with schizophrenia: A multinomial modeling approach

Patients with schizophrenia (SCZ) consistently show prospective memory (PM) impairments, and the technique of implementation intentions has been shown to improve PM performance in these patients. PM is considered to have prospective and retrospective components. However, it remains unclear which component of PM is impaired in patients with SCZ and which component(s) is facilitated by implementation intentions (II). The present study aimed to examine these two issues. Forty-two patients with SCZ and 42 matched healthy controls were randomly assigned to an II group or a typical instruction group. All participants were administered a color-matching PM task. Results showed that, using a multinomial-modeling approach, patients with SCZ exhibited impairment in the retrospective component of PM. In addition, while II improved the prospective PM component in healthy controls, both prospective and retrospective PM components in patients with SCZ were improved. Together, our results shed light on the mechanism of PM impairment in SCZ patients and the mechanism of II in improving PM performance.

Event-, Time- and Activity-Based Prospective Memory in Children with ADHD

ABSTRACTWe examined prospective memory (PM) function in children with attention deficit hyperactivity disorder (ADHD). A group of 28 children with ADHD and 28 typically developing children completed event-, time- and activity-based PM tasks and attention tests. ADHD children had impaired attention but intact PM performance. Both groups performed best in activity-based PM tasks, followed by event-based PM tasks, and performed worst in time-based PM tasks. ADHD children had lower ongoing task performance in the event-based PM task. The findings indicate that children with ADHD may have an intact PM, but this may be at the cost of ongoing task performance.

Structural correlates of commission errors in prospective memory

Prospective memory refers to remembering to perform an intended future action, such as remembering to take medication with breakfast. Historically, the field has focused on failures to initially remember a prospective memory task (omission errors), but interestingly, individuals will occasionally repeat a prospective memory action after it has been completed (e.g., double dosing). These failures in prospective memory deactivation/forgetting are termed commission errors. The current registered study investigated structural neuroimaging correlates of a laboratory measure of commission errors in 47 healthy older adults. Extant theories differed in their predicted outcomes: commission error risk was predicted to be highest in individuals with smaller medial temporal lobe volume (output monitoring theory), larger lateral prefrontal cortex volume (residual activation theory), or a combination of larger medial temporal lobe volume and smaller lateral prefrontal cortex volume (dual mechanisms theory). In registered analyses, we found that a higher number of commission errors was associated with larger medial temporal lobe/hippocampal grey matter volume (supporting dual mechanisms theory), but not with grey or white matter volume in the lateral parietal lobe, frontal pole, or a composite of ventrolateral/dorsolateral prefrontal cortex (not supporting dual mechanisms theory). In post hoc analyses, smaller volume in the lateral orbitofrontal cortex was associated with a higher number of commission errors, possibly indicating that the dual mechanisms theory of PFC control was conceptually correct, but that a different PFC subregion than anticipated exerts control over commission errors. Collectively, the registered and post hoc analysis findings showed a functional dissociation across MTL/PFC regions that was more consistent with the dual mechanisms theory than the alternative theories.

Beyond prospective memory retrieval: Encoding and remembering of intentions across the lifespan

Combining behavioral and electrophysiological measures, we investigated the role of memory processes for prospective memory development in three different age groups over the lifespan. We focused on age differences during intention encoding, retention and retrieval in order to assess if potential age-associated performance differences in adolescence and older age can be explained by associated neurophysiological differences. Our research aim was to understand the impact of memory-related factors such as intention load and encoding time on prospective remembering, focusing especially on encoding and retention, which are two so far scarcely investigated phases. Adolescents, younger and older adults worked on a semantic judgment task with an embedded prospective memory task. Participants had to encode either one or two intentions; the encoding time was either four or eight seconds long. Younger and older adults outperformed adolescents behaviorally. Furthermore, performance was better for remembering one intention compared to remembering two intentions. On the neural level, we found age-specific modulations for the fronto-polar slow wave (FPSW) and the temporal-parietal slow wave (TPSW) that were sensitive to the number of intentions. Adolescents showed differences between encoding one or two intentions in the FPSW, while older adults showed these differences for the TPSW. Maintaining an intention increased fronto-central sustained activity compared to no intention. Furthermore, the activity during intention maintenance was sensitive to the number of intentions. Prospective positivity amplitudes during retrieval were smallest in adolescents and largest in older adults, but were not influenced by the memory manipulations. Parietal slow wave activity increased with increasing number of intentions, reflecting post-retrieval coordination between the ongoing and prospective memory task. In sum, only activity of the FPSW and the TPSW showed that age-related differences were influenced by memory-related factors during encoding, whereas these interactions were not observed for retention or retrieval. Our findings suggest that intention encoding and its efficiency play an important role in explaining age differences in prospective memory.

No Effect of Transcranial Direct-Current Stimulation to Dorsolateral Prefrontal Cortex on Naturalistic Prospective Memory in Healthy Young and Older Adults

Transcranial direct current stimulation (tDCS), a form of non-invasive brain stimulation, has been shown to enhance working memory and multitasking abilities. Because of the substantial overlap in both cognitive processes (maintenance, monitoring) and neural substrates (dorsolateral prefrontal cortex, DLPFC) that support both working memory and prospective memory – the ability to remember to perform intended actions at appropriate moments in the future (taking medications, turning off appliances) – we tested whether tDCS would also enhance young and older adults’ prospective memory. If tDCS enhances DLPFC activation, then it should benefit prospective memory performance, particularly for tasks that rely on controlled monitoring processes for prospective memory cue detection. Healthy young and older adults played the Virtual Week game while they received either a session of active tDCS to DLPFC and then, after at least 48 h, a session of placebo-controlled, sham stimulation, or vice versa. The Virtual Week game is a reliable measure of naturalistic prospective memory that includes assessments of five different types of prospective memory tasks that vary in cue-type (time vs. event) and task-regularity and, thus, the extent to which task performance should rely on controlled monitoring processes and DLPFC activation. Active tDCS had no effect on prospective memory performance relative to sham tDCS for either age group or any task type. In contrast, there were reliable practice effects across test sessions regardless of whether active tDCS was applied during the first or second session. A single session of tDCS to DLPFC did not enhance young or older adults’ prospective memory performance, but practice did.

Compensatory strategy use improves real-world functional performance in community dwelling older adults.

Compensatory strategies such as assistive technology, external reminders, and environmental cues may help support instrumental activities of daily living (IADLs) and independence. However, functional ability is most often evaluated in clinical settings where everyday compensation cannot be readily observed. The present study used a novel, real-world evaluation of everyday activities (prospective memory, household chores, complex IADLs, and planning tasks) to examine the impact of compensation. Fifty community dwelling older adults were recruited with cognitive status ranging from healthy to mildly impaired. Participants completed a battery of validated performance-based and cognitive tasks, an IADL questionnaire (also completed by an informant), and real-world activities carried out in their own homes. The real-world evaluation demonstrated adequate interrater reliability (intraclass coefficient = 0.92) and construct validity (r = 0.55). Compensation improved real-world task outcome on prospective memory and household chores tasks. Further, cognition emerged as a moderator between compensation and prospective memory task outcome. Participants' ratings on an IADL questionnaire were related to real-world and performance-based functioning whereas informants' ratings were related to performance-based tasks and cognition. Our results suggest that proxy measures of functional ability (i.e., performance-based, cognitive, and IADL questionnaire measures) do not fully capture the complexity of real-world performance for nondemented community dwelling older adults. Compensation appeared to improve prospective memory performance, particularly for individuals with average to low average cognitive abilities. A difference in IADL questionnaire ratings suggest that participants may be better able to judge their real-world performance than informants. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Toward a better understanding of costs in prospective memory: A meta-analytic review.

In prospective memory (PM) research, a common finding is that people are slower to perform an ongoing task with concurrent PM demands than to perform the same task alone. This slowing, referred to as costs, has been seen as reflecting the processes underlying successful PM. Historically, costs have been interpreted as evidence that attentional capacity is being devoted toward detecting PM targets and maintaining the intention in working memory; in other words, the claim is that participants are monitoring. A new account, termed delay theory, instead suggests that costs indicate a strategic speed/accuracy adjustment in favor of accuracy, allowing more time for PM-related information to reach its own threshold. Taking a meta-analytic approach, we first review studies in the PM literature that have reported ongoing task performance, both with and without a concurrent PM task, identifying key factors suitable for the meta-analysis. Next, we analyze the data of these studies, using our factors as moderators in a series of metaregressions, to determine their impact on the presence or magnitude of PM-related costs. Finally, we interpret the results of the meta-analysis from both monitoring and delay perspectives in an effort to better understand the nature of costs and what they reflect about the underlying cognitive processes involved in PM. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Investigating prospective memory via eye tracking: No evidence for a monitoring deficit in older adults

Prospective memory (PM) refers to remembering to perform intended actions in the future. Older adults in particular have been shown to be negatively affected by PM tasks that require a high amount of attentional resources (i.e., nonfocal tasks). This age-related PM deficit has been attributed to reduced target monitoring in this age group older adults. However, this conclusion was based on indirect measures of monitoring, such as costs of the ongoing task.The present study set out to 1) investigate older adults' PM target monitoring by, for the first time, employing a direct measure (i.e., eye tracking), 2) assess differences in monitoring between PM tasks that differ in their focality, and 3) examine whether differences in PM monitoring can indeed explain older adults' reduced PM performance in nonfocal tasks.Results demonstrate that while older, but not younger adults, showed reduced performance in a nonfocal PM task, overt monitoring (eye movements) of these groups did not differ between focality conditions. Further analyses showed that older adults' performance was still reduced on the strategically more demanding task after controlling for overt target monitoring (i.e., including only trials in which the participant monitored).In contrast to indirect measures of cue monitoring, our findings illustrate that older adults' deficits on nonfocal PM tasks cannot (exclusively) be explained by reduced monitoring. Instead, processing that takes place after target monitoring are discussed as possible mechanisms underlying older adults' reduced PM performance in nonfocal tasks.

Cognitive Flexibility Improves Memory for Delayed Intentions.

The ability to delay the execution of a goal until the appropriate time, prospective memory (PM), can be supported by the following two different cognitive control strategies: proactive control involving working memory maintenance of the goal and active monitoring of the environment; or reactive control relying on timely retrieval of goal information from episodic memory. Certain situations tend to favor each strategy, but the manner in which individuals adjust their strategy in response to changes in the environment is unknown. Across two experiments, human participants performed a delayed-recognition PM task embedded in an ongoing visual search task that fluctuated in difficulty. A control strategy was identified from moment to moment using reaction time costs and fMRI measures of goal maintenance. We found that people fluidly modified control strategies in accordance with changes in task demands (e.g., shifting toward proactive control when task difficulty decreased). This cognitive flexibility proved adaptive as it was associated with improved PM performance.

Prospective Memory Relates to Attentional Control: Differential Patterns in Old Age

Aims: We investigated the associations of prospective memory (PM) with memory, attentional control, and conscientiousness and whether they differed between young-old (YO) and old-old adults (OO). Methods: We analyzed data from 562 older adults (mean = 80.04 years) who were tested on four PM tasks, memory (immediate and delayed cued recall), attentional control (letter and category fluency), and reported conscientiousness. Results: Latent variable analyses showed that in both YO and OO PM was associated with memory and attentional control (but not conscientiousness). Notably, testing for moderation effects revealed that the relation between PM and attentional control was significantly stronger in YO than in OO. Conclusion: YO may be able to better (than OO) achieve a good PM performance with good attentional control.

Prospective Memory Predictions in Aging: Increased Overconfidence in Older Adults

ABSTRACTIntroduction: This study investigated whether young and older adults can predict their future performance on an event-based prospective memory (PM) task. Methods: Metacognitive awareness was assessed by asking participants to give judgments-of-learning (JOLs) on an item-level for the prospective (remembering that something has to be done) and retrospective (remembering what to do) PM component. In addition, to explore possible age differences in the ability to adapt predictions to the difficulty of the task, encoding time and the relatedness between the prospective and the retrospective PM component were varied. Results: Results revealed that both age groups were sensitive to our task manipulations and adapted their predictions appropriately. Moreover, item-level JOLs indicated that for the retrospective component, young and older adults were equally accurate and slightly overconfident. For the prospective component, predictions were fairly accurate in young adults, while older adults were overconfident. Thus, results suggest that general overconfidence is increased in older adults and concerns both components of PM. Discussion: Findings regarding the conceptual differences between the prospective and retrospective components of a PM task, as well as the link between aging and metamemory in PM are discussed.

ProspecFit

Prospective Memory (PM), which involves remembering to perform intended actions, is the primary source of everyday memory lapses. While existing solutions mostly focus on supportive memory aids and reminders, it is also crucial to maintain PM functions and independent living for older adults. We present ProspecFit, which digitises implementation intentions, a lab-based memory intervention, making it available on smartphones through iterative design that draws insights from a focus group and preliminary studies. We evaluated its usability and effectiveness in enhancing PM through user studies that included a 12-day in situ study, and pre- and post-testing with 10 adults (61 to 80 years old). Participants in the digital PM training group were more prompt in performing the in situ PM tasks, compared to the control group without digital training, and reported improvement in their PM compared to before the training. We also show findings from diary entries, reports on forgetful moments and user reactions. Our work provides implications for creating digital memory training tools in HCI.

Age Differences in Prospective Memory: A Further Evaluation of the Executive Framework

ABSTRACTAccording to the executive framework of prospective memory (PM), age-related differences in PM performance are mediated by age-related differences in executive functioning (EF). The present study further explored this framework by examining which specific components of EF are associated with PM differences between and within three age groups. A group of children (7–9 years; N = 108), adolescents (12–14 years; N = 112), and adults (17–23 years; N = 106) performed focal- and non-focal event-based PM (EBPM) tasks, a time-based PM (TBPM) task, and tasks measuring EF components. Differences between age groups in focal EBPM, non-focal EBPM, and TBPM performance were mediated by, respectively, differences in interference control and response inhibition, performance on the ongoing task, and differences in working memory and response inhibition. However, within-age group analyses only revealed WM updating as significant predictor of TBPM performance in the adolescent group. These results support and further qualify the executive framework of PM. The differences in outcome dependent on the examined age range might be important for explaining mixed results of previous studies regarding the precise EF components underlying age-related PM task performance differences.

Time-of-day effects on prospective memory

Cognitive performance fluctuates during the course of a day. Different cognitive functions show optimal performance at different times of the day, known as the ‘time-of-day effect’. While this effect has been observed for a number of cognitive domains including declarative memory, it is presently unclear whether performance fluctuations are also seen in prospective memory, i.e. memory for intentions to be realized in the future. The present study examined time-of-day effects in four different prospective memory tasks with varying degrees of complexity, taking into account circadian preference (i.e. morningness-eveningness/chronotype) and attentional resources (in one of the tasks). In a pilot study (n = 48) and a main experiment (n = 39), prospective memory was compared between morning groups (˜09:00) and evening groups (˜21:00) of young adults. We found time-of-day effects, with better performance in the evening than in the morning, in a simple one-item prospective memory task (Red Pencil Task, p = .02), a classical event-based prospective memory task including the detection of cue syllables in a lexical decision ongoing task (Syllable Detection Task, p < .048), and a rather naturalistic complex planning task for breakfast preparation (Dresden Breakfast Task, including time-based prospective memory (p = .026) and event-based prospective memory (p = .054)). These time-of-day effects were neither modulated by circadian preference nor by attentional resources. Another simple one-item prospective memory task was not affected by time of day (Color Task, p = .14). Ongoing task performance in the Syllable Detection Task and the Dresden Breakfast Task, overall, did not differ significantly between morning and evening groups. These findings provide tentative evidence for time-of-day effects in prospective memory of young adults, with better performance in the evening hours.

Social engagement after stroke – is it relevant to cognitive function? A cross-sectional analysis of UK Biobank data

Background: Findings from studies in older adult populations suggest that measures of social engagement may be associated with health outcomes, including cognitive function. Plausibly the magnitude and direction of this association may differ in stroke. The disabling nature of stroke increases the likelihood of social isolation and stroke survivors are at high risk of cognitive decline. We assessed the association between social engagement and cognitive function in a sample of stroke survivors. Methods: We included available data from stroke survivors in the UK Biobank (N=8776; age range: 40-72; 57.4% male). In a series of regression models, we assessed cross-sectional associations between proxies of social engagement (frequency of family/friend visits, satisfaction with relationships, loneliness, opportunities to confide in someone, participation in social activities) and performance on domain specific cognitive tasks: reaction time, verbal-numerical reasoning, visual memory and prospective memory. We adjusted for demographics, health-, lifestyle-, and stroke-related factors. Accounting for multiple testing, we set our significance threshold at p&lt;0.003. Results: After adjusting for covariates, we found independent associations between faster reaction times and monthly family visits as compared to no visit (standardised beta=-0.32, 99.7% CI: -0.61 to -0.03, N=4,930); slower reaction times and religious group participation (standardised beta=0.25, 99.7% CI 0.07 to 0.44, N=4,938); and poorer performance on both verbal-numerical reasoning and prospective memory tasks with loneliness (standardised beta=-0.19, 99.7% CI: -0.34 to -0.03, N=2,074; odds ratio=0.66, 99.7% CI: 0.46 to 0.94, N=2,188; respectively). In models where all proxies of social engagement were combined, no associations remained significant. Conclusions: We found limited task-specific associations between cognitive performance and proxies of social engagement, with only loneliness related to two tasks. Further studies are necessary to confirm and improve our understanding of these relationships and investigate the potential to target psychosocial factors to support cognitive function in stroke survivors.