Future thinking improves prospective memory performance and plan enactment in older adults

Practice is the best of all instructors-Effects of enactment encoding and episodic future thinking on prospective memory performance in high-functioning adults with autism spectrum disorder

Prospective memory (PM) is the ability to remember to carry out intended actions in the future. The present study investigated the effects of episodic future thinking (EFT) and enactment encoding (EE) on PM performance in autistic adults (ASD). A total of 72 autistic individuals and 70 controls matched for age, gender, and cognitive abilities completed a computerized version of the Dresden breakfast Task, which required participants to prepare breakfast following a set of rules and time restrictions. A two (group: ASD vs. controls) by three (encoding condition: EFT vs. EE vs. standard) between-subjects design was applied. Participants were either instructed to engage in EFT or EE to prepare to the different tasks prior to performing the Dresden breakfast or received standard instructions. Analyses of variance were conducted. Autism-spectrum-disorders (ASD) participants did not differ from control participants in their PM performance, regardless of which strategy they used. Compared to the standard condition, EE but not EFT improved time-based PM performance in all participants. This is the first study to find spared time-based PM performance in autistic individuals. The results confirm earlier results of beneficial effects of EE on PM performance. Findings are discussed with regards to the methodology used, sample composition as well as autistic characteristics.

The effect of impulsive personality traits on prospective memory under different task importance conditions

BACKGROUND

Prospective memory (PM) refers to the ability to perform planned activities in the appropriate future situations. It needs to be planned in advance and processed through multiple stages such as encoding, retention, retrieval, and execution, which usually require more attention resources. Impulsivity trait individuals are usually characterized by lack of consideration, premature expression, excessive risk-taking and easy to make inappropriate reaction, so they are more likely to show disadvantages in PM. Nevertheless, increasing the importance of PM tasks can promote more adequate and effective cue encoding, and encourage individuals to devote attention to PM tasks, which may change the disadvantage of impulsivity individuals in PM performance.

METHODS

In this study, the between-subjects design of 2 (trait type: high-impulsivity trait, low-impulsivity trait) ×2 (task importance: important, unimportant) was adopted in the experiment, the 2-back task was used for the ongoing task, and the focal cues were used for the PM task cues.

RESULTS

The results showed that the PM accuracy of high-impulsivity trait individuals was lower than that of low-impulsivity trait individuals under the task unimportant condition, but there was no difference between the two traits groups under the task important condition.

CONCLUSIONS

The results of this study suggested that high-impulsivity trait individuals had a deficit in PM performance, but emphasizing the importance of PM tasks can compensate for their disadvantage in PM performance.

Naturalistic assessments in virtual reality and in real life help resolve the age-prospective memory paradox

 Cognitive aging researchers have long reported "paradoxical" age differences in prospective memory (PM), with age deficits in laboratory settings and age benefits (or no deficits) in real-world settings. We propose a theoretical account that explains this "age-PM-paradox" as a consequence of both methodological factors and developmental changes in cognitive abilities and personality traits. To test this account, young  and older  adults   performed a series of naturalistic PM tasks in the lab and real world. Age-related PM deficits were observed in both lab-based tasks where demands were implemented using virtual reality and in-person role-playing. In contrast, older adults performed equal to or better than young adults on both real-world tasks, where demands were implemented in participants' daily lives. Consistent with our proposed account, an index of these "paradoxical" effects was partially predicted by age-related differences in working memory, vigilance, agreeableness, and neuroticism, whose predictive utility varied across task settings.

Real-world compensatory strategy use in community-dwelling mid-life and older adults: An evaluation of quality

Objective: Older adults often spontaneously engage in compensatory strategies (CS) to support everyday task completion, but factors that influence success of chosen CS remain unclear. This study examines whether real-world prospective memory (PM) task completion is better predicted by CS count or a CS quality rating. Method: Seventy mid-life and older adult participants were presented four novel, real-world PM tasks via remote assessment and encouraged to use their typical CS. The examiner captured detailed information about planned CS at task presentation (T1) and utilized CS at follow-up testing (T2). From this information, count (CS Count; quantity of CS) and quality (CS Quality; rating of CS thoroughness and utility) scores were coded separately for the planned and utilized CS. PM task performance accuracy was also coded (PM Accuracy). Results: Hierarchical regressions revealed planned CS Count and Quality did not predict PM Accuracy. In contrast, the utilized CS Quality predicted a significant amount of PM Accuracy variance over and above CS Count, global cognition, and age (R2 = .47, ΔR2 = .24, ΔF = 29.36, p < .001, f2 = .45). Furthermore, utilized CS Quality accounted for a similar amount of variance in PM Accuracy when utilized CS Count was removed from the model. Conclusions: This study's CS coding system can capture and quantify the quality of strategies, which uniquely predicts real-world PM performance. This coding system may provide researchers with a nuanced CS measure and lead to improved CS interventions designed to support everyday PM performance, such as targeted CS trainings.

Relationship Between Future Thinking and Prospective Memory in Alzheimer's Disease

Background

Future thinking and prospective memory are two cognitive processes oriented toward the future and reliant on the ability to envision oneself in future scenarios.

Objective

We explored the connection between future thinking and prospective memory in individuals with Alzheimer's disease (AD).

Methods

We invited both AD participants and control participants to engage in event-based prospective memory tasks (e.g., "please hand me this stopwatch when I inform you there are 10 minutes remaining") and time-based prospective memory tasks (e.g., "close the book you are working on in five minutes"). Additionally, we asked participants to engage in a future thinking task where they imagined upcoming events.

Results

Analysis revealed that AD participants exhibited lower performance in both prospective memory tasks and future thinking compared to the control group. Importantly, we identified significant positive correlations between the performance on event- and time-based prospective memory tasks and future thinking abilities among AD participants.

Conclusions

These findings underscore the connection between the decline in both prospective memory domains and the ability to envision future events in individuals with AD. Our results also shed light on the challenges AD individuals face when trying to project themselves into the future to mentally pre-experience upcoming events.

Development of the Virtual Kitchen Protocol for Prospective Memory: a virtual reality-based measure of everyday prospective memory abilities

INTRODUCTION

Prospective memory is the ability to remember to accomplish a task at a specified point in the future. While this cognitive ability has a large impact on daily functioning, it is rarely assessed during neuropsychological evaluations. Furthermore, existing clinical prospective memory measures are few in number and have significant limitations, including applicability to everyday functioning and appropriate norming for older adulthood. There are also many gaps in the literature on prospective memory, such as how environmental factors affect performance across the lifespan.

METHOD

In the current study, we develop and establish a new virtual reality-based measure of prospective memory, the Virtual Kitchen Protocol for Prospective Memory. Young adults (ages 18-29; n = 56), healthy older adults (ages 60-90; n = 94), and clinical older adults (ages 62-90; n = 30) were compared on their performances on both the developed virtual reality prospective memory test and a parallel paper-and-pencil prospective memory test to investigate the impact of test environment across participant group.

RESULTS

The Virtual Kitchen Protocol for Prospective Memory was found to adequately differentiate between young adult, healthy older adult, and clinical older adult populations - suggesting baseline ability for prospective memory assessment in clinical settings with older adults and potential for future improvement of neuropsychological evaluations. Additionally, the developed virtual prospective memory task appeared to mimic environmental factors in everyday life but did not replicate the benefit previously measured in healthy older adults' prospective memory ability in naturalistic settings.

CONCLUSIONS

Overall, the current study built upon extant knowledge of prospective memory in both normal and abnormal aging, suggesting future directions in replicating familiar home environments. Findings provided additional evidence toward future validation of virtual reality assessment tools in clinical neuropsychological evaluations of cognitive abilities, such as prospective memory, with both healthy and clinical older adult populations.

The benefits of mind wandering on a naturalistic prospective memory task

Mind wandering (MW) occurs when our attention spontaneously shifts from the task at hand to inner thoughts. MW is often future-oriented and may help people remember to carry out their planned actions (Prospective Memory, PM). Past-oriented MW might also play a critical role in boosting PM performance. Sixty participants learned 24 PM items and recalled them during an immersive virtual walk in a town. The items were divided into event-based-EB and time-based-TB. During the PM retention phase, participants were randomly assigned to a high or a low cognitive load condition, in order to manipulate MW frequency. Some PM items were encoded before this MW manipulation (pre-PM) and some during the virtual walk (post-PM). A high MW frequency was linked with better global PM performances. Spontaneous past-oriented MW predicted better pre-EB retrospective PM retrieval, while spontaneous future-oriented MW predicted better Pre-EB prospective PM retrieval. Voluntary future-oriented MW predicted better post-EB retrospective retrieval. We highlighted, for the first time, a differential impact of spontaneous MW content depending on the PM component (retrospective or prospective). Past-oriented MW is crucial for (re)consolidating PM intentions, and episodic future thinking MW for the execution of PM intentions. We discuss the twofold functional role of MW, namely, to consolidate an already programmed intention and to plan future actions.

Parkinson's disease disrupts the ability to initiate and apply episodic foresight

OBJECTIVE

While Parkinson's disease is associated with impairments in many aspects of prospective cognition, no study to date has tested whether these difficulties extend to problems using episodic foresight to guide future-directed behavior. To provide the first examination of whether people with Parkinson's disease are impaired in their capacity to initiate and apply episodic foresight.

METHOD

People with Parkinson's disease (n = 42), and a demographically matched neurotypical comparison group (n = 42) completed a validated behavioral assessment that met strict criteria for assessing episodic foresight (Virtual Week-Foresight), as well as a broader neurocognitive and clinical test battery.

RESULTS

People with Parkinson's disease were significantly less likely than the comparison group to acquire items that would later allow a problem to be solved and were also less likely to subsequently use these items for problem resolution. These deficits were largely unrelated to performance on other cognitive measures or clinical characteristics of the disorder.

CONCLUSIONS

The ability to engage in episodic foresight in an adaptive way is compromised in Parkinson's disease. This appears to be a stable feature of the disorder, and one that is distinct from other clinical symptoms and neurocognitive deficits. It is now critical to establish exactly why these difficulties exist and how they impact on real-life functional capacity.

Simulating the best and worst of times: the powers and perils of emotional simulation

We are remarkably capable of simulating events that we have never experienced. These simulated events often paint an emotional picture to behold, such as the best and worst possible outcomes that we might face. This review synthesises dispersed literature exploring the role of emotion in simulation. Drawing from work that suggests that simulations can influence our preferences, decision-making, and prosociality, we argue for a critical role of emotion in informing the consequences of simulation. We further unpack burgeoning evidence suggesting that the effects of emotional simulation transcend the laboratory. We propose avenues by which emotional simulation may be harnessed for both personal and collective good in applied contexts. We conclude by offering important future directions.

Prospective Memory Training in Older Adults: A Systematic Review and Meta-Analysis

Prospective memory (PM), which enables one to remember to carry out delayed intentions, is crucial for everyday functioning. PM commonly deteriorates upon cognitive decline in older adults, but several studies have shown that PM in older adults can be improved by training. The current study aimed to summarise this evidence by conducting a qualitative systematic analysis and quantitative meta-analysis of the effects of PM training in older adults, for which systematic searches were conducted across seven databases (Cochrane Library, Embase, PubMed, PsycInfo, Web of Science, CINAHL and Scopus). Forty-eight studies were included in the qualitative analysis, and 43% of the assessed PM training interventions showed positive gains in enhancing PM. However, the methodological quality varied across the studies, with 41% of the non-randomised control trials (non-RCTs) rated as having either serious or critical risk of bias. Therefore, only 29 RCTs were included in the subsequent quantitative meta-analysis. We found a significant and moderate immediate efficacy (Hedges' g = 0.54) of PM training in enhancing PM performance in older adults, but no significant long-term efficacy (Hedges' g = 0.21). Two subgroup analyses also revealed a robust training efficacy across the study population (i.e., healthy and clinical population) and the number of training sessions (i.e., single session and programme-based). Overall, this study provided positive evidence to support PM training in older adults. Further studies are warranted to explore the mechanisms by which PM training exerts its effects, and better-quality RCTs are needed to provide more robust evidence supporting our findings.

Prospective Memory Training for Healthy Older Adults: A Systematic Review

OBJECTIVES

This review systematically synthesizes existing evidence of prospective memory training for healthy older adults (> 55 years). Existing prospective memory training include strategy-based, process-based and combined regimens. Strategy-based training focuses on different mnemonics to compensate for aging declines in prospective memory. Process-based training aims to restore related cognitive processes to support prospective memory. Combined training utilizes both strategy-based and process-based regimens to enhance prospective memory performance.

METHODS

A total of 349 studies were identified from the Cochrane Library, EBSCO, PsycINFO and PubMed databases.

RESULTS

Using predefined inclusion and exclusion criteria, 11 studies were included in the review. There were six studies of strategy-based training, two studies of process-based training and three studies of combined training.

CONCLUSIONS

Overall, strategy-based training appears to facilitate prospective memory for healthy older adults. However, it is impossible to draw conclusions for process-based and combined training due to the preliminary nature of current evidence.

CLINICAL IMPLICATIONS

Mental imagery or the use of external aids can be useful strategy-based approaches to facilitate prospective memory in older adults. Strategy-based training should target multiple prospective memory phases simultaneously to encourage transfers. Further studies will be required to draw conclusions on the effectiveness of process-based and combined training.

On the evolution of a functional approach to memory

In an analysis of memory systems, Sherry and Schacter (Psychological Review, 94, 439-454, 1987) emphasized the importance of functional and evolutionary considerations for characterizing mechanisms of memory. The present article considers four different yet closely related topics from more recent research in which similar considerations have played a prominent role in shaping both experiment and theory: the seven sins of memory, mechanisms underlying memory misattribution errors, the role of memory in imagining future experiences, and the relation between associative inference and memory errors. These lines of research illustrate the usefulness of attempting to integrate functional and mechanistic considerations, in line with the general approach articulated by Sherry and Schacter.

Imagine to Remember: An Episodic Future Thinking Intervention to Improve Medication Adherence in Patients with Type 2 Diabetes

PURPOSE

Medication nonadherence is prevalent in diabetic populations, with "forgetting" a commonly cited reason. This issue of forgetfulness is due, in part, to a failure of prospective memory (PM). Episodic future thinking (EFT) has been shown to improve PM but has not been used to improve medication adherence.

PATIENTS AND METHODS

The current study used a multiple baseline design (N = 4) to test the effects of EFT on medication non-adherence for four patients with a diagnosis of type 2 diabetes or prediabetes, with comorbid high blood pressure or high cholesterol. Medication adherence was objectively measured over 15 weeks using medication event monitoring systems.

RESULTS

Results of visual analysis showed medication adherence was reliably improved, confirmed by mixed model analysis of variance (p < 0.001), with significant differences from baseline to treatment (Tau <0.05) for 3 of 4 participants. Improvements in two measures of PM (effect size (ES) = 0.73, 0.80) and delay discounting (ES = 1.20) were observed.

CONCLUSION

This study provides a feasible way to improve medication adherence in patients with prediabetes or type 2 diabetes.

Brief inductions in episodic past or future thinking: effects on episodic detail and problem-solving

Episodic specificity inductions, involving brief training in recollecting episodic details, have been shown to improve subsequent performance on tasks involving remembering the past, imagining the future and problem solving. The current study examined if specificity inductions targeting self-referential past or future episodic thinking would have dissociable effects on generating past and future episodic detail and problem solving. Sixty-three participants were randomised to either a past self-referential or future self-referential episodic induction. All participants also completed a control task. Participants randomised to the self-referential future thinking induction generated more episodic details on past and future narrative tasks compared to a control task, whereas participants randomised to a self-referential past thinking induction showed similar performance to the control task. When examining within-group performance of participants randomised to the past or future induction, we found some evidence of dissociable effects of inductions on narrative generation tasks, but not on problem solving outcomes. Our findings suggest that self-referential inductions may be useful for increasing episodic specificity, but that the temporal distance and direction of the induction matters. We discuss our results in the context of the potential clinical utility of this approach for populations vulnerable to autobiographical memory disruption.

Subjective Time in Dementia: A Critical Review

The capacity for subjective time in humans encompasses the perception of time's unfolding from moment to moment, as well as the ability to traverse larger temporal expanses of past- and future-oriented thought via mental time travel. Disruption in time perception can result in maladaptive outcomes-from the innocuous lapse in timing that leads to a burnt piece of toast, to the grievous miscalculation that produces a traffic accident-while disruption to mental time travel can impact core functions from planning appointments to making long-term decisions. Mounting evidence suggests that disturbances to both time perception and mental time travel are prominent in dementia syndromes. Given that such disruptions can have severe consequences for independent functioning in everyday life, here we aim to provide a comprehensive exposition of subjective timing dysfunction in dementia, with a view to informing the management of such disturbances. We consider the neurocognitive mechanisms underpinning changes to both time perception and mental time travel across different dementia disorders. Moreover, we explicate the functional implications of altered subjective timing by reference to two key and representative adaptive capacities: prospective memory and intertemporal decision-making. Overall, our review sheds light on the transdiagnostic implications of subjective timing disturbances in dementia and highlights the high variability in performance across clinical syndromes and functional domains.

Prospective memory deficits following acute alcohol consumption

BACKGROUND

Prospective memory is a critical neurocognitive capacity that refers to the ability to execute delayed intentions. To date, few studies have investigated the effects of acute alcohol consumption on prospective memory, and important questions remain about the mechanisms that might underpin acute alcohol-induced prospective memory impairment.

AIMS

The current study sought to clarify the nature and magnitude of prospective memory difficulties following acute alcohol consumption and to test the degree to which any problems with prospective remembering might be a secondary consequence of broader cognitive impairment. This study also investigated whether there were potential sex differences.

METHODS

In all, 124 healthy adult social drinkers were assigned to either the alcohol (n = 61) or placebo (n = 63) condition. Participants were administered a dose of 0.6 g/kg alcohol or a matched placebo drink and then asked to complete a measure of prospective memory. A broader neurocognitive test battery was also administered.

RESULTS

Relative to the placebo condition, acute alcohol intoxication led to significant impairment on all prospective memory tasks, with effects mostly large in magnitude. These difficulties could not be explained by broader problems in retrospective memory, executive function or episodic future thinking. In addition, females recorded a higher blood alcohol concentration than males; however, no sex differences in prospective memory performance were identified following acute alcohol use.

CONCLUSION

The results show that acutely, even a moderate dose of alcohol substantially impairs prospective memory function. These findings have potentially important implications for understanding many of the maladaptive behaviours associated with acute alcohol consumption.

The role of semantic memory in prospective memory and episodic future thinking: new insights from a case of semantic dementia

Prospective memory (PM), the ability to remember to execute planned actions, and episodic future thinking (EFT), the ability to imagine future personal events, are two core aspects of future-oriented cognition. The present study aimed for the first time at examining the role of semantic memory loss in PM and EFT in a single case patient (SL) at the early stage of semantic dementia.First, we investigated various types of PM as well as episodic memory of new events using a validated ecological assessment via virtual reality. Second, we examined EFT using a temporally extended version of the TEMPau task, which measures episodic aspects of remembering the past and imagining the future taking temporal distance into account.Patient SL was deficient in semantically linked event-based PM and was unable to provide any EFT for the most distant period but was preserved in other types of PM and near and intermediate EFT.These findings provide new evidence on the role of semantic memory in PM depending on the type of intention and in EFT depending on the temporal distance mirroring autobiographical memory. Finally, they point out a specific link between PM and near EFT in future-oriented cognition.

Revisiting the Age-Prospective Memory Paradox Using Laboratory and Ecological Tasks

Prospective memory (PM) is the ability to perform a planned action at a future time. Older adults have shown moderate declines in PM, which are thought to be driven by age-related changes in the prefrontal cortex. However, an age-PM paradox is often reported, whereby deficits are evident in laboratory-based PM tasks, but not naturalistic PM tasks. The key aims of this study were to: (1) examine the age-PM paradox using the same sample across laboratory and ecological settings; and (2) determine whether self-reported PM and cognitive factors such as working memory and IQ are associated PM performance. Two PM tasks were administered (ecological vs. laboratory) to a sample of 23 community-dwelling older adults (M_age = 72.30, SD_age = 5.62) and 28 young adults (M_age = 20.18, SD_age = 3.30). Participants also completed measures of general cognitive function, working memory, IQ, and self-reported memory. Our results did not support the existence of the age-PM paradox. Strong age effects across both laboratory and ecological PM tasks were observed in which older adults consistently performed worse on the PM tasks than young adults. In addition, PM performance was significantly associated with self-reported PM measures in young adults. For older adults, IQ was associated with time-based PM. These findings suggest that the age-PM paradox is more complex than first thought and there are differential predictors of PM performance for younger and older adults.

Effectiveness of a Visual Imagery Training Program to Improve Prospective Memory in Older Adults with and without Mild Cognitive Impairment: A Randomized Controlled Study

Prospective memory (PM) problems in aging and, to a greater extent, in mild cognitive impairment (MCI), compromise functional independence. This study examined the effectiveness of a cognitive training program based on visual imagery to improve PM among older adults with and without MCI. Participants were older adults, 24 with MCI and 24 cognitively healthy (HOA). Half of them (12 MCI and 12 HOA) were randomly assigned to the PM training program, the other half to the no-training control group. All participants also completed a pre- and post-test evaluation, including neuropsychological tests, questionnaires, and the Ecological Test of Prospective Memory (TEMP). There was no significant effect of the intervention on the TEMP total, event-based or time-based scores for either the MCI or HOA groups. However, the trained MCI group committed fewer false alarms (i.e., more efficient identification of prospective cues) in the event-based condition of the TEMP at post-test. On the other hand, all trained participants performed better than control participants on retrospective memory tests, which suggests that visual imagery-based training is more effective to improve retrospective memory than PM. Possible explanations for these results are explored.

Future and past autobiographical memory in persons with HIV disease

Objective: While HIV disease is associated with impairment in declarative memory, the ability of people with HIV (PWH) to describe past and future autobiographical events is not known. Method: Participants included 63 PWH and 28 seronegative individuals ages 50-78 who completed standardized neurocognitive and everyday functioning assessments. Participants described four events from the recent past and four imagined events in the near future, details from which were classified as internal or external to the main event. Result: PWH produced fewer autobiographical details with small-to-medium effect sizes but did not differ from seronegative participants in meta-cognitive ratings of their performance. Performance of the study groups did not vary across past or future probes or internal versus external details; however, within the entire sample, past events were described in greater detail than future events, and more external than internal details were produced. Within the PWH group, the production of fewer internal details for future events was moderately associated with poorer prospective memory, executive dysfunction, and errors on a laboratory-based task of medication management. Conclusion: Older PWH may experience difficulty generating autobiographical details from the past and simulated events in the future, which may be related to executive dyscontrol of memory processes. Future studies might examine the role of future thinking in health behaviors such as medication adherence and retention in healthcare among PWH. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Effects of Mental Imagery on Prospective Memory: A Process Analysis in Individuals with Amnestic Mild Cognitive Impairment

INTRODUCTION

Prospective memory (PM) is a multiphasic cognitive function important for autonomy and functional independence but is easily disrupted by pathological aging processes. Through cognitive simulation of perceptual experiences, mental imagery could be an effective compensatory strategy to enhance PM performance. Nevertheless, relevant research in individuals with amnestic mild cognitive impairment (MCI) has been limited, and the underlying mechanism of the therapeutic effect has not been sufficiently elucidated. The present study aimed to examine complex PM performances and the effect of mental imagery on each phase in older adults with MCI and to investigate the underlying cognitive mechanism from a process perspective.

METHODS

Twenty-eight MCI and 32 normal aging controls completed a seminaturalistic PM task, in addition to a series of neuropsychological tests. Participants from each group were randomly assigned to a mental imagery condition or a standard repeated encoding condition before performing the PM task. Four indices were used to measure performance in the intention formation, intention retention, intention initiation, and intention execution phases of PM. Performances in each phase was compared between the 2 diagnostic groups and the 2 instruction conditions.

RESULTS

The MCI group performed worse than the normal aging group in the intention formation and intention retention phases. The participants in the mental imagery condition performed significantly better than those in the standard condition during the intention formation, intention retention, and intention execution phases, regardless of the diagnostic group. Moreover, there was a significant interaction between the group and condition during intention retention, showing that people with MCI benefited even more from mental imagery than normal aging in this phase. Performance in the intention retention phase predicted performance in the intention initiation and intention execution phases.

DISCUSSION

PM deficits in MCI mainly manifest during planning and retaining intentions. Mental imagery was able to promote performance in all but the initiation phase, although a trend for improvement was observed in this phase. The effects of mental imagery may be exerted in the intention retention phase by strengthening the PM cue-action bond, thereby facilitating the probability of intention initiation and bolstering fidelity to the original plan during intention execution.

Spontaneous and deliberate future thinking: a dual process account

In this article, we address an apparent paradox in the literature on mental time travel and mind-wandering: How is it possible that future thinking is both constructive, yet often experienced as occurring spontaneously? We identify and describe two 'routes' whereby episodic future thoughts are brought to consciousness, with each of the 'routes' being associated with separable cognitive processes and functions. Voluntary future thinking relies on controlled, deliberate and slow cognitive processing. The other, termed involuntary or spontaneous future thinking, relies on automatic processes that allows 'fully-fledged' episodic future thoughts to freely come to mind, often triggered by internal or external cues. To unravel the paradox, we propose that the majority of spontaneous future thoughts are 'pre-made' (i.e., each spontaneous future thought is a re-iteration of a previously constructed future event), and therefore based on simple, well-understood, memory processes. We also propose that the pre-made hypothesis explains why spontaneous future thoughts occur rapidly, are similar to involuntary memories, and predominantly about upcoming tasks and goals. We also raise the possibility that spontaneous future thinking is the default mode of imagining the future. This dual process approach complements and extends standard theoretical approaches that emphasise constructive simulation, and outlines novel opportunities for researchers examining voluntary and spontaneous forms of future thinking.

Improving prospective memory in school-aged children: Effects of future thinking and performance predictions

Recently, event-based prospective memory (PM) performance of children has been shown to benefit from different encoding strategies such as imagining the execution of a future PM task (i.e., future thinking) and making performance predictions (i.e., metacognitive monitoring). This study aimed to investigate whether and how these two encoding strategies affect PM performance alone and in combination. For this purpose, 127 children aged 8-11 years were assigned to four encoding conditions: (a) standard, (b) performance predictions, (c) future thinking, and (d) future thinking + performance predictions. The ongoing task performance costs (i.e., attentional monitoring), working memory (WM) span, and metacognitive monitoring judgments, such as task difficulty expectations, performance postdictions, confidence judgments, and strategy use, were also evaluated among participants. The results show that combining future thinking instructions with performance predictions considerably improved children's PM performance without incurring additional attentional monitoring costs. Moreover, whereas children generally tended to overestimate their PM performance, more realistic lower-performance predictions were related to higher PM scores for children in the combined condition. Finally, age, WM, and strategy use significantly predicted PM performance independent of the encoding condition. This study is the first to demonstrate that combining future thinking instructions with performance predictions enhances children's PM performance compared with each encoding strategy alone. Moreover, this work is the first to show that by simply imagining the execution of a PM task, children's prediction accuracy can be improved, which is significantly related to the PM performance advantage.

Fostering Self-Management of Everyday Memory in Older Adults: A New Intervention Approach

Traditional memory strategy training interventions improve older adults' performance on tests of episodic memory, but have limited transfer to episodic memory tasks, let alone to everyday memory. We argue that an alternative approach is needed to assist older adults to compensate for age-related cognitive declines and to maintain functional capacity in their own natural ecologies. We outline a set of principles regarding how interventions can successfully train older adults to increase successful goal pursuit to reduce risks of everyday memory failures. We argue that training individuals to use metacognitive self-regulatory strategies to proactively manage formulation and pursuit of daily goals can compensate for age-related cognitive changes and increase the likelihood of goal attainment. We then describe an intervention approach that instantiates these principles in a multi-modal intervention that is unique in its three-phase approach: (1) individualized assessment of an individual's current approaches to self-regulation; (2) training memory strategies, self-management skills, and new habits of mind in a group training context; and (3) a behavioral shaping period in which individuals receive coaching and feedback on their efforts to use trained procedures to improve everyday cognition. A recently completed study conducted an initial test of the intervention, with highly encouraging results. We advocate further efforts to replicate, extend, and fine-tune this type of intervention. The ultimate goal is to be able to deliver the intervention in a way that increases its potential reach, including to subpopulations of older adults at risk for everyday cognitive impairments.

Rational use of episodic and working memory: A normative account of prospective memory

Humans often simultaneously pursue multiple plans at different time scales, a capacity known as prospective memory (PM). The successful realization of non-immediate plans (e.g., post package after work) requires keeping track of a future plan while accomplishing other intermediate tasks (e.g., write a paper). Prospective memory capacity requires the integration of noisy evidence from perceptual input with evidence from both short-term working memory (WM) and long-term or episodic memory (LTM/EM). Here we formulate a set of empirical studies of prospective memory, all dual-task problems, as problems of computational rationality. We ask how a rational model should integrate noisy perceptual evidence and memory to maximize payoffs in these PM studies. The model combines reinforcement learning (optimal action selection) with evidence accumulation (optimal inference) in order to derive good decision parameters for optimal task performance (i.e., performing an ongoing task while monitoring for a cue that triggers executing a second prospective task). We compare model behavior to human behavioral evidence of key accuracy and reaction time phenomena in PM. Notably, our normative approach to theorizing and modeling these phenomena makes no assumptions about mechanisms of attention or retrieval. This approach can be extended to study the learning and use of meta-parameters governing the boundedly rational use of memory in planned action in health and disease. A computational psychiatry extension of the model can capture compensatory mnemonic strategies in neuropsychiatric disorders that may be rational responses to disturbances of inference, memory, and action selection.

Cognitive mechanisms of episodic simulation in psychiatric populations

Episodic simulation is the construction of a mental representation of a specific autobiographical future event. Episodic simulation has increasingly been studied in psychiatric populations. Here we 1) review evidence indicating that episodic simulation is compromised in patients with depression, anxiety, schizophrenia, bipolar disorder, and PTSD; and 2) consider several potential cognitive mechanisms of episodic simulation in psychiatric populations: episodic retrieval, scene construction, mental imagery, components of the CaRFAX model (i.e., capture and rumination, functional avoidance, and executive functioning), and narrative style. We evaluate evidence regarding these mechanisms across psychiatric populations, and identify areas of future research. Understanding the factors that contribute to episodic simulation impairment in psychiatric populations may lead to targeted and effective treatment approaches.

Looking on the Bright Side: Aging and the Impact of Emotional Future Simulation on Subsequent Memory

OBJECTIVES

When younger adults simulated positive future events, subsequent memory is positively biased. In the current studies, we explore age-related changes in the impact of emotional future simulation on subsequent memory.

METHODS

In Experiment 1, younger and older adults simulated emotional future events before learning the hypothetical outcome of each event via narratives. Memory was assessed for emotional details contained in those narratives. In Experiment 2, a shorter temporal delay between simulation and narrative encoding was used to reduce decay of simulation memory over time.

RESULTS

Future simulation did not bias subsequent memory for older adults in Experiment 1. However, older adults performed similar to younger adults in Experiment 2, with more liberal responses to positive information after positive simulation.

DISCUSSION

The impact of an optimistic outlook on subsequent memory is reduced with age, which may be at least partly attributable to declining memory for future simulations over time. This work broadens our understanding of the functional consequences of age-related declines in episodic future simulation and adds to previous work showing reduced benefits of simulation with age on tasks tapping adaptive functions.

Emotion matters: The influence of valence on episodic future thinking in young and older adults

In young adults, valence not only alters the degree to which future events are imagined in rich episodic detail, but also how memorable these events are later on. For older adults, how valence influences episodic detail generation while imagining future events, or recalling these details at another time, remains unclear. We investigated the effect of valence on the specificity and memorability of episodic future thinking (EFT) in young and older adults. Among young and older adults, negative EFT was accompanied by less episodic detail generation relative to positive and neutral EFT. A similar reduction in episodic specificity for negative EFT was found two days later when participants recalled their previously imagined events. Notably, while older adults generated less episodically specific future thoughts relative to young adults, age did not influence the effect of valence on episodic detail generation at imagination or recollection.

Aware of the Future?

Abstract. Futures Consciousness refers to the capacity that a person has for understanding, anticipating, and preparing for the future. Although the concept is widely used in the field of futures research, no quantitative tool exists yet that assesses it. Drawing from a recent five-dimensional model that considers Time perspective, Agency beliefs, Openness to alternatives, Systems perception, and Concern for others as interrelated sub-dimensions of a general construct of Futures Consciousness, we developed a composite 20-item scale that measures Futures Consciousness as an interindividual difference. The psychometric properties of this new scale were examined through a dual approach of exploratory and confirmatory factorial analyses with a total of 1,301 participants in three languages (English, French, and Finnish). The scale’s structure proved satisfactory and fitted the hypothesized five-dimensional model in all three languages. Measures of internal and external validity (convergent and concurrent) also indicated good psychometric properties. Notably, individuals’ scores were positively related to the adoption of several social future-oriented behaviors such as pro-environmental and civic behavior. As such, the developed scale proves a reliable tool that could be of use for scholars and practitioners in futures studies as well as psychology.

Does Episodic Future Thinking Repair Immediacy Bias at Home and in the Laboratory in Patients With Prediabetes?

OBJECTIVE

This study aimed to determine if episodic future thinking (EFT) can decrease delay discounting (DD) among adults with prediabetes both in and out of the laboratory. DD measures how much the value of a reinforcer decreases as a function of the delay to receive it.

METHODS

Adults with prediabetes (n = 67) completed a three-session study. At session 1, baseline measures (including DD) were collected. At sessions 2 and 3, participants were prompted to engage in either EFT or control episodic thinking (CET) while completing DD and other measures. In addition, between the completion of sessions 2 and 3, participants engaged in EFT or CET at home and completed DD tasks remotely via smartphones or other Internet-connected devices.

RESULTS

Results showed significant -1.2759 (-20.24%) reductions in DD in the EFT group compared with a + 0.0287 (+0.46%) DD increase in the CET group (p = .0149) in the laboratory; and -0.4095 (-8.85%) reduction in DD in the EFT group compared with a + 0.2619 (+5.64%) increase in the CET group (p = .011) at home. Working memory (measured by Backwards Corsi and Digit Span) was found to moderate the effects of EFT on some measures of DD. EFT did not change measures from the food purchase task or a food ad libitum procedure.

CONCLUSIONS

Results show that EFT decreases DD in and out of the laboratory and supports the further exploration of EFT as an intervention for prediabetes and related chronic diseases.

CLINICAL TRIAL REGISTRATION

NCT03664726.

Autobiographical Memory Content and Recollection Frequency: Public Release of Quantitative Datasets and Representative Classification Analysis

Autobiographical memory (AM), the recollection of personally-experienced events, has several adaptive functions and has been studied across numerous dimensions. We previously introduced two methods to quantify across the life span AM content (the amount and types of retrieved details) and the everyday occurrence of its recollection. The CRAM (cue-recalled autobiographical memory) test used naturalistic word prompts to elicit AMs. Subjects dated the memories to life periods and reported the numbers of details recalled across eight features (e.g., spatial detail, temporal detail, people, and emotions). In separate subjects, an experience sampling method quantified in everyday settings the frequency of AM retrieval and of mental representation of future personal events or actions (termed prospective memory: PM); these data permit evaluation of the temporal orientation of episodic recollection. We describe these datasets now publicly released in open access (CRAM: doi.org/10.6084/m9.figshare.10246958; AM-PM experience-sampling: doi.org/10.6084/m9.figshare.10246940). We also present examples of data mining, using cluster analyses of CRAM (14,242 AMs scored for content from 4,244 subjects). Analysis of raw feature scores yielded three AM clusters separated by total recalled content. Normalizing for total content revealed three classes of AM based on the relative contributions of each feature: AMs containing a relatively large number of details related to people, AMs containing a high degree of spatial information, and AMs with details equally distributed across features. Differences in subject age, memory age, and total content were detected across feature clusters. These findings highlight the value in additional mining of these datasets to further our understanding of autobiographical recollection.

Episodic future thinking together with observational learning benefits prospective memory in high-functioning Korsakoff's syndrome patients

Objective

Patients with Korsakoff’s syndrome (KS) have difficulty carrying out tasks which rely on prospective memory (PM). Since remembering to carry out an action in the future is crucial for living independently, it is of primary interest to develop strategies that improve PM performance in KS patients.

Design

The study employed a computer categorization task as an ongoing activity into which a PM task was embedded. We included episodic future thinking (EFT) and observational learning (Experiment 2) to boost PM.

Methods

Experiment 1 evaluated the efficacy of EFT following written PM task instructions in ten KS patients. Due to floor‐level PM performance in Experiment 1, Experiment 2 included an instructional video demonstrating the PM intention. In Experiment 2, twenty‐six KS patients performed both conditions (EFT and no‐EFT) at least 1 week apart, while twelve controls with alcohol use disorder without KS performed the no‐EFT condition. In Experiment 2, the PM instructions were also shown through video (observational learning component). Mild cognitive impairment was assessed in a short test battery.

Results

Experiment 1 showed overall floor performance in both conditions. Experiment 2 showed that KS patients performed PM tasks less accurately than the control group in the no‐EFT condition. In Experiment 2, where the observational learning component was included, EFT improved PM performance in KS patients. This effect was driven by a sub‐group of high‐functioning KS patients.

Conclusions

This study showed the value of an observational learning component together with EFT in improving PM performance, in relatively high‐functioning KS patients.

Practitioner points

KS patients performed the PM task less accurately than non‐KS controls with alcohol use disorder, confirming PM impairment in this patient population.

Controls with alcohol use disorder performed the PM task at ceiling level.

Showing an instructional video demonstrating the PM intention improved PM performance and later recall of PM task instructions in KS patients.

Episodic future thinking strategy improved PM performance in KS patients with relatively intact cognitive functioning.

Neural and clinical changes of cognitive behavioural therapy versus talking control in patients with major depression: a study protocol for a randomised clinical trial

INTRODUCTION

While major depression causes substantial distress and impairment for affected individuals and society, the effectiveness of cognitive behavioural therapy (CBT) in treating the condition has been established. However, the therapeutic mechanism underlying the efficacy of CBT remains unknown. This study aimed to describe a protocol for a randomised controlled trial that will measure the CBT-induced clinical and neural changes in patients with non-psychotic major depression.

METHODS AND ANALYSIS

The current study is a 16-week assessor-blinded, randomised, parallel-group trial with a 12-month follow-up as part of usual depression care at an outpatient clinic. Patients aged 20-69 years with major depressive disorder will be randomly assigned to receive either CBT in addition to their usual treatment or talking control in addition to their usual treatment for 16 weeks. The primary outcome is the functional changes in the brain areas that have been associated with future-oriented thinking at 16 weeks; secondary outcomes include changes in functional brain connectivity, severity and changes in the scores of objective and subjective clinical depression symptoms, proportion of responders and remitters and quality of life. The intention-to-treat analysis will be used.

ETHICS AND DISSEMINATION

All protocols and the informed consent form are compliant with the Ethics Guideline for Clinical Research (Japanese Ministry of Health, Labour and Welfare). Ethical Review Committees at the Keio University School of Medicine have approved the study protocol (version 3, 11 September 2017). We will disseminate research findings to scientific and general audiences through national and international conference presentations as well as lay summaries to the general public, including mental health consumer and publications in international peer-reviewed psychiatry and brain imaging journals.

TRIAL REGISTRATION NUMBER

UMIN Clinical Trials Registry (UMIN000018155); Pre-results.

The fuzzy future: Time horizon, memory failures, and emotional distress in gambling disorder

This study aimed to first investigate the interplay among self-rated ability in both retrospective and prospective memory, time perspective, and negative affectivity to gambling severity. Two hundred and three habitual players took part in the study. Participants were administered the South Oaks Gambling Screen (SOGS), the Consideration of Future Consequences scale (CFC-14), the Prospective and Retrospective Memory Questionnaire (PRMQ), as well as the Depression, Anxiety and Stress Scales-21 (DASS-21). Overall, data indicated that the higher the involvement in gambling, the higher the depression levels and the shorter the time horizon. The results of linear regression analysis showed that, along with gender, years of education, depression, and inattention to the future consequences of actual behavior, the negative self-perception of prospective memory functioning represents a significant predictor of gambling severity. Finally, to clarify if depression was on the path from prospective memory to gambling severity or if prospective memory was the mediator of the impact of depression on gambling severity, data were submitted to path analysis. Results indicated that depression has a direct effect on gambling severity and mediates the association between prospective memory and gambling involvement. The relation between gambling severity and prospective memory scores suggests that impairment in prospective memory plays a key role in adult problematic gambling.

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.

Prospective memory partially mediates the association between aging and everyday functioning

Objective: Older adults commonly experience declines in everyday functioning, the reasons for which are multifactorial. Prospective memory (PM), or remembering to carry out intended actions, can be an executively demanding cognitive process that declines with older age and is independently associated with a variety of everyday functions (e.g. taking medication). This study examined the hypothesis that PM mediates the relationship between older age and poorer everyday functioning.Method: A total of 468 community-dwelling adults (ages 18-75) with a range of medical comorbidities (e.g. viral infection) were classified as dependent on four well-validated measures of manifest everyday functioning: activities of daily living, employment status, the Karnofsky Scale of Performance Status, and self-reported cognitive symptoms. Participants completed the Memory for Intentions Test (MIsT) to measure PM, alongside clinical tests of executive functions and retrospective memory.Results: Controlling for education and comorbidities, bootstrap analysis revealed a significant direct effect of age on everyday functioning and a significant mediated effect of age on everyday functioning through the indirect effect of time-based b = .006 [.003, .010] and event-based PM (b = .005, [.002, .009]), as well as slightly smaller effects for executive functions (b = .003, [.001, .005]) and retrospective memory (b = .002, [.001, .005]).Conclusions: These cross-sectional data suggest that executively demanding aspects of declarative memory play an important partial mediating role between an individual factor (i.e. age) and daily life activities, and highlight the possible benefit of targeting PM for improving everyday functioning in older adults.

Frontopolar cortex activation associated with pessimistic future-thinking in adults with major depressive disorder

Background

Pessimistic thinking about the future is one of the cardinal symptoms of major depressive disorder (MDD) and is an important domain of cognitive functioning associated with hopelessness. Neuroimaging studies have shown that the frontopolar cortex (Brodmann area [BA] 10) is involved in thinking about the future and demonstrated that patients with MDD have dysfunctions in BA10. However, the relationship between pessimistic thinking about the future and brain activity is unclear. Hence, we aimed to compare brain activity during future-thinking between patients with MDD and healthy individuals.

Methods

We assessed 23 patients with current MDD and 23 healthy individuals. Participants were instructed to imagine the future or to recall the past using the future-thinking paradigm with four distinct temporal conditions (distant future, near future, distant past, and near past) during functional MRI. Resting-state functional MRI was also performed to explore the functional connectivity of BA10.

Results

Compared with healthy individuals, patients with MDD had greater negative thinking about the distant future and exhibited increased activation in the medial BA10 when imagining the distant future, following small-volume correction focusing on the frontopolar a priori region of interest (family-wise error correction p < 0.05). Increased positive functional correlation between the right BA10 seed region and the posterior cingulate cortex was also observed.

Conclusion

Patients with MDD who show greater pessimistic thinking about the distant future demonstrate increased activation in the frontopolar cortex. These findings are consistent with the hypothesis that frontopolar cortical dysfunction plays a key role in the hopelessness that manifests in patients with MDD.

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Pessimistic thinking about the future is one of the cardinal symptoms of MDD.

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Patients with MDD showed greater negative thinking about the distant future.

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MDD who show greater pessimistic future-thinking demonstrate higher activation in the frontopolar cortex (BA10).

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Resting-functional connectivity from right BA10 to PCC was increased in MDD.

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Frontopolar cortical dysfunction may play a key role in the hopelessness that manifests in patients with MDD.

Prospective memory (partially) mediates the link between ADHD symptoms and procrastination

Individuals with attention deficit hyperactivity disorder (ADHD) often show poor planning and poor organization of tasks and activities which has been related to reduced memory for delayed intentions (prospective memory) and procrastination-in addition to other cognitive or motivational factors. This study set out to bring the fields of prospective memory and procrastination research together and to explore possible relations between the two constructs in ADHD. Twenty-nine adults with ADHD and 24 healthy controls performed several laboratory-based and real-life prospective memory tasks and filled in questionnaires measuring their symptom severity and procrastination behaviour. Overall, individuals' with ADHD showed clear deficits in everyday prospective memory performance. Individuals with ADHD recalled and executed less of their own real-life intentions. Moreover, there were clear links between everyday prospective memory performance and reported procrastination behaviour, and everyday prospective memory performance mediated the link between ADHD symptoms and procrastination behaviour.

Spontaneous Activation of Event Details in Episodic Future Simulation

Episodic future simulation is supported by both the retrieval and recombination of episodic details. It remains unclear, however, how individuals retrieve episodic details from memory to construct possible future scenarios; for this people must use details related to the planned future events appropriately. A potentially relevant cognitive process is the spontaneous activation of intention observed in prospective memory (i.e., the intention superiority effect). Previous studies on prospective memory have shown that the approximation of retrieval opportunities for future intentions activate related information, suggesting that the intention superiority effect is context-sensitive. We hypothesized that the same cognitive process underlies future simulation—that is, details related to future events should spontaneously become activated at the appropriate moment of future simulation to make that simulation plausible. In Experiment 1, participants took part in future experiments and formed intentions to perform particular actions for the next experiments. Subsequently, they imagined events that could occur up until they arrived at the experimental room on the day of the next experiment. During this exercise, they did not imagine engaging in the required experimental task. We measured the conceptual activation of intention-related information via a recognition task using intended action words as targets. The results showed the intention superiority effect—concepts related to participants’ future intentions became active when envisioning future events approaching the next experiment. In Experiments 2 and 3, we ensured that the intention superiority effect in future simulation was context-sensitive by adding a control condition that required participants to imagine events other than the approaching future experiments. These results indicated that concepts related to the intended actions were spontaneously activated when imagined future events became both temporally and spatially close to the future simulation. Our finding suggests that spontaneous activation of details approaching the context of a future simulation helps in constructing plausible future scenarios.

The Functions of Prospection - Variations in Health and Disease

Much of human life revolves around anticipating and planning for the future. It has become increasingly clear that this capacity for prospective cognition is a core adaptive function of the mind. Here, we review the role of prospection in two key functional domains: goal-directed behavior and flexible decision-making. We then survey and categorize variations in prospection, with a particular focus on functional impact in clinical psychological conditions and neurological disorders. Finally, we suggest avenues for future research into the functions of prospection and the manner in which these functions can shift toward maladaptive outcomes. In doing so, we consider the conceptualization and measurement of prospection, as well as novel approaches to its augmentation in healthy people and managing its alterations in a clinical context.

The relationship between episodic future thinking and prospective memory in middle childhood: Mechanisms depend on task type

Episodic future thinking (EFT), the ability to imagine experiencing a future event, and prospective memory (PM), the ability to remember and carry out a planned action, are core aspects of future-oriented cognition that have individually been the focus of research attention in the developmental literature. However, the relationship between EFT and PM, including the extent to which it varies with PM task type, remains poorly delineated, particularly in middle childhood. The current study tested this relationship in 62 typically developing children aged 8-12 years. Results indicated that EFT ability was significantly related to performance on three types of PM tasks (regular and irregular event based and regular time based). Age was not found to moderate the relationship. Children's performance on the retrospective memory component of the PM tasks mediated the relationship between EFT ability and their performance on three types of PM tasks. For irregular event-based tasks, however, EFT made an additional significant contribution. This study adds to the limited empirical literature supporting a relationship between EFT and PM in this age band and supports theoretical models arguing that EFT ability may support PM performance by strengthening the encoding of PM task details in retrospective memory. However, additional mechanisms were also indicated for irregular event-based PM tasks, possibly involving strengthening of cue-context associations. These data show for the first time that the contribution of EFT to children's PM performance varies across task types. This study provides an important and novel contribution to current understanding of the processes that underlie PM development.

Better imagined: Neural correlates of the episodic simulation boost to prospective memory performance

Episodic simulation is an adaptive process that can support goal-directed activity and planning success. We investigated the neural architecture associated with the episodic simulation improvement to the likelihood of carrying out future actions by isolating the brain regions associated with this facilitation in a prospective memory paradigm. Participants performed a lexical decision task by making word/non-word judgments, with rarely occurring prospective memory target words requiring a pre-specified manual response. Prior to scanning, participants were given exposure to two lists of prospective memory targets: animals and tools. In a fully counterbalanced design, participants generated a rhyme to one target list and imagined their subsequent encounter (episodic simulation) with target words on the other list. Replicating prior behavioral work, episodic simulation improved subsequent prospective memory performance. Brain activation was assessed in a multivariate partial least squares analysis. Relative to lexical decision blocks with no prospective memory demand, sustained prospective memory replicated prior observations of frontal polar activation. Critically, maintaining the intention to respond to simulated targets, over and above rhyme targets, engaged middle frontal and angular gyri, and medial parietal and prefrontal cortices. Transient activity associated with prospective memory target hits revealed activation for simulated targets in medial prefrontal cortex, posterior cingulate, lateral temporal lobe and inferior parietal lobule. In contrast, rhyme target hits engaged more left lateralized dorsolateral prefrontal cortex and anterior insula. Episodic simulation, thus effectively shifts executive control strategy and boosts task performance. These results are consistent with a growing body of evidence implicating executive control and default network region interactions in adaptive, goal-directed behavior.