Prospective memory in context: Moving through a familiar space

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.

Development and validation of a novel Context-Based Prospective Memory Task among neurotypical adults

PURPOSE

To address the paucity and potential of context-based prospective memory (PM) assessment tasks suitable to Indian ethnicity, the study aimed to develop a novel context-based PM task and determine its psychometric properties among neurotypical adults.

METHODS

Rendered images in 2-D were extracted from a 3-D shopping mall, where PM and ongoing tasks were embedded within them to provide participants with a semi-immersive experience. The design and scoring of the novel task were constructed in alignment with the Memory for Intentions Screening Test. Fifty neurotypical adults in and around Mangaluru were recruited. The Memory of Intentions Test (MIST) and novel context-based PM task were administered.

RESULTS

The validity of the novel task was established with a Content Validity Index of 0.98. The intraclass correlation for the test-retest reliability of the novel context-based PM task was 0.92 (p<0.001) and the inter-rater reliability was 0.98 (p<0.001). The internal consistency of the six subscales was high (Cronbach's α= 0.86), and the Spearman-Brown coefficient indicated a strong split-half reliability of 0.87. Spearman's correlation showed that the trials exhibited strong connections to the dichotomic characteristics of the subscales to which they belonged. Further, McNemar's test suggested similar profiles of the participants for the MIST and novel task.

CONCLUSION

The results of the present study suggest that the novel context-based PM task offers good validity and reliability measures, providing valuable insight into the mechanisms of PM, and therefore, could be ideal for inclusion in a battery of cognitive assessments.

Strategic monitoring improves prospective memory: A meta-analysis

Monitoring the environment for target events that trigger prospective memory (PM) retrieval requires cognitive resources, reflected by costs to ongoing task performance (i.e., worse accuracy and/or slower response times). Strategic monitoring refers to the use of context to engage or disengage monitoring when a PM target is anticipated or unanticipated. Laboratory strategic monitoring studies have found mixed results as to whether context specification improves PM performance. This study employed a meta-analytic technique to assess the overall effect of context specification on PM performance and ongoing task metrics of strategic monitoring. Overall, context specification improved PM performance when the target was anticipated and improved ongoing task performance (speed and accuracy) when the target was not anticipated. Moderator analyses revealed the degree of slowing in anticipated contexts predicted how much context specification improved PM performance. However, the benefits to PM performance from context specification differed by the type of procedure used. PM performance was improved when context changes could be predicted during blocked or proximity procedures, but not when context varied randomly in trial-level procedures. These results provide insights into the mechanisms underlying strategic monitoring and guidance for researchers on which procedures to be use depending on the theory-driven questions.

External Time Monitoring in Time-Based Prospective Memory: An Integrative Framework

We propose a new integrative framework of external time monitoring in prospective memory (PM) tasks and its relation with performance. Starting from existing empirical regularities and our theoretical analysis, the framework predicts that external monitoring in PM tasks comprises a first stage of loose monitoring to keep track of the passage of time, and a subsequent stage of finer-grained monitoring, based on interval reduction, to meet the PM deadline. Following our framework, we predicted and observed in three different datasets (N = 375): (1) a marked increase in external monitoring frequency in the final part of the period of the PM task, well captured by a proportional rate exponential growth function; (2) a positive association between individual compliance with this monitoring pattern and PM performance; (3) a positive relation between monitoring frequency in the time window immediately preceding the PM deadline and PM performance at the individual level; and (4) good individual compliance with an interval reduction pattern in external monitoring, especially in the time window closer to the PM deadline. These results support the proposed integrative framework, which has the potential to foster future research on external monitoring in PM and in other fields of cognitive science.

Prospective memory assessment: Scientific advances and future directions

Prospective Memory (PM), the ability to remember to realize intended actions in the future, is crucial for maintaining autonomy. Decades of research has focused on a so-called age PM paradox, where older adults outperformed younger adults on some PM tasks, but not others. Contributing to this paradox is heterogeneity in and a lack of valid assessment methods. Previous research showed a lack of convergent validity between performance-based PM and both self-report and informant-report measures. We argue that questionnaires may be relevant to obtain information regarding patients’ awareness of their PM difficulties but need to be used in conjunction with performance-based tools. Within performance-based PM tools there are also difficulties in measurement: 15–60 min experimental tasks and batteries have a good reliability but cannot usually fit in a standard clinical evaluation, while shorter PM measures have lower reliability and sensitivity. In this perspective paper, we encourage researchers to develop more ecologically valid tools. Innovative PM paradigms that allow participants to generate their own intentions and that take task costs into consideration should be developed. Future research will also need to focus on cognitive factors, personality and online evaluation, to improve PM assessment and develop ad-hoc rehabilitation programs.

Towards an animal model of consciousness based on the platform theory

The evolution of intellectual capacities has brought forth a continuum of consciousness levels subserved by neuronal networks of varying complexity. Brain pathologies, neurodegenerative, and mental diseases affect conscious cognition and behavior. Although impairments in consciousness are among the most devastating consequences of neurological and mental diseases, valid and reliable animal models of consciousness, that could be used for preclinical research are missing. The platform theory holds that the brain enters a conscious operation mode, whenever mental representations of stimuli, associations, concepts, memories, and experiences are effortfully maintained (in working memory) and actively manipulated. We used the platform theory as a framework and evaluation standard to categorize behavioral paradigms with respect to the level of consciousness involved in task performance. According to the platform theory, a behavioral paradigm involves conscious cognitive operations, when the problem posed is unexpected, novel or requires the maintenance and manipulation of a large amount of information to perform cognitive operations on them. Conscious cognitive operations are associated with a relocation of processing resources and the redirection of attentional focus. A consciousness behavioral test battery is proposed that is composed of tests which are assumed to require higher levels of consciousness as compared to other tasks and paradigms. The consciousness test battery for rodents includes the following tests: Working memory in the radial arm maze, episodic-like memory, prospective memory, detour test, and operant conditioning with concurrent variable-interval variable-ratio schedules. Performance in this test battery can be contrasted with the performance in paradigms and tests that require lower levels of consciousness. Additionally, a second more comprehensive behavioral test battery is proposed to control for behavioral phenotypes not related to consciousness. Our theory could serve as a guidance for the decryption of the neurobiological basis of consciousness.

Distinct monitoring strategies underlie costs and performance in prospective memory

Prospective memory (PM) describes the ability to remember to perform goal-relevant actions at an appropriate time in the future amid concurrent demands. A key contributor to PM performance is thought to be the effortful monitoring of the environment for PM-related cues, a process whose existence is typically inferred from a behavioral interference measure of reaction times. This measure, referred to as "PM costs," is an informative but indirect proxy for monitoring, and it may not be sufficient to understand PM behaviors in all situations. In this study, we asked participants to perform a visual search task with arrows that varied in difficulty while concurrently performing a delayed-recognition PM task with pictures of faces and scenes. To gain a precise measurement of monitoring behavior, we used eye-tracking to record fixations to all task-relevant stimuli and related these fixation measures to both PM costs and PM accuracy. We found that PM costs reflected dissociable monitoring strategies: higher costs were associated with early and frequent monitoring while lower costs were associated with delayed and infrequent monitoring. Moreover, the link between fixations and PM costs varied with cognitive load, and the inclusion of fixation data yielded better predictions of PM accuracy than using PM costs alone. This study demonstrates the benefit of eye-tracking to disentangle the nature of PM costs and more precisely describe strategies involved in prospective remembering.

Flexible attention allocation dynamically impacts incidental encoding in prospective memory

Remembering to fulfill an intention at a later time often requires people to monitor the environment for cues that it is time to act. This monitoring involves the strategic allocation of attentional resources, ramping attention up more in some contexts than others. In addition to interfering with ongoing task performance, flexibly shifting attention may affect whether task-irrelevant information is later remembered. In the present investigation, we manipulated contextual expectations in event-related prospective memory (PM) to examine the consequences of flexible attention allocation on incidental memory. Across two experiments, participants completed a color-matching task while monitoring for ill-defined (Experiment 1) or specific (Experiment 2) PM targets. To manipulate contextual expectations, some participants were explicitly told about the trial types in which PM targets could (or not) appear, while others were given less precise or no expectations. Across experiments, participants' color-matching decisions were slower in high-expectation trials, relative to trials when targets were not expected. Additionally, participants had better incidental memory for PM-irrelevant items from high-expectation trials, but only when they received explicit contextual expectations. These results confirm that participants flexibly allocate attention based on explicit trial-by-trial expectations. Furthermore, the present study indicates that greater attention to item identity yields better incidental memory even for PM-irrelevant items, irrespective of processing time.

Improving prospective memory with contextual cueing

Prospective memory (PM) involves remembering to perform an intended action in the future. Researchers have demonstrated that, under certain conditions, contextual information about when PM performance opportunities are likely to occur can support PM performance while decreasing the cognitive demands of the PM task. The current study builds upon prior work to investigate whether warning participants that a PM-relevant context was approaching would improve the efficiency of PM control processes and benefit PM accuracy. Participants completed an ongoing lexical decision task with an embedded PM task of responding to a target syllable. For context conditions, targets only appeared on trials where letter strings were colored red (PM-relevant context), while PM-irrelevant trials were green. The warning in Experiment 1 was embedded in the ongoing task (trials preceding PM-relevant contexts were colored yellow). In Experiment 2 the warning was separate from the ongoing task (1-s pre-trial red fixation preceding PM-relevant contexts). Context improved PM control efficiency and PM accuracy in both experiments. Context always improved PM accuracy for targets in the second and third trial positions of PM-relevant contexts; however, only the Experiment 2 warning generated an accuracy benefit for targets in the first trial position. Experiment 3 replicated the findings of Experiments 1 and 2 and also confirmed that color change without associated context was not responsible for the current results.

Prospective Memory Performance in Simulated Air Traffic Control : Robust to Interruptions but Impaired by Retention Interval

OBJECTIVE

To examine the effects of interruptions and retention interval on prospective memory for deferred tasks in simulated air traffic control.

BACKGROUND

In many safety-critical environments, operators need to remember to perform a deferred task, which requires prospective memory. Laboratory experiments suggest that extended prospective memory retention intervals, and interruptions in those retention intervals, could impair prospective memory performance.

METHOD

Participants managed a simulated air traffic control sector. Participants were sometimes instructed to perform a deferred handoff task, requiring them to deviate from a routine procedure. We manipulated whether an interruption occurred during the prospective memory retention interval or not, the length of the retention interval (37-117 s), and the temporal proximity of the interruption to deferred task encoding and execution. We also measured performance on ongoing tasks.

RESULTS

Increasing retention intervals (37-117 s) decreased the probability of remembering to perform the deferred task. Costs to ongoing conflict detection accuracy and routine handoff speed were observed when a prospective memory intention had to be maintained. Interruptions did not affect individuals' speed or accuracy on the deferred task.

CONCLUSION

Longer retention intervals increase risk of prospective memory error and of ongoing task performance being impaired by cognitive load; however, prospective memory can be robust to effects of interruptions when the task environment provides cuing and offloading.

APPLICATION

To support operators in performing complex and dynamic tasks, prospective memory demands should be reduced, and the retention interval of deferred tasks should be kept as short as possible.

Hey buddy, why don't we take it outside: An experience sampling study of prospective memory

Relatively little research has focused on how prospective memory (PM) operates outside of the laboratory, partially due to the methodological problems presented by naturalistic memory research in general and by the unique challenges of PM in particular. Experience sampling methods (ESM) offer a fruitful avenue for this type of research, as recent work from Gardner and Ascoli (Psychology and Aging, 30, 209-219, 2015) has shown. They found that people thought about PM around 15% of the time, and that future thinking was more common than past thinking. In two studies, we replicated our own findings and those reported by Gardner and Ascoli. To summarize, people think about the future more often than the past (30% compared to 13%), and PM occupies our thoughts approximately 13-15% of the time, supporting claims made by some researchers that our episodic memory systems are forward-looking (Klein in Journal of Applied Research in Memory and Cognition, 2, 222-234, 2013). Of those PM thoughts, participants reported that 61% were internally cued, rather than externally triggered. Through the use of multi-level modeling, we additionally found that PM thoughts were more likely when the respondant was alone than with people, and earlier in the day. Finally, we found that participants higher in neuroticism were more likely to report thinking of PM, and that this was driven entirely by the anxiety facet. Most generally, we hope to have demonstrated the value of ESM to help researchers investigate and understand naturalistic PM.

Location-based prospective memory

This study explores location-based prospective memory. People often have to remember to do things when in a particular location, such as buying tissues the next time they are in the supermarket. For event cognition theory, location is important for structuring events. However, because event cognition has not been used to examine prospective memory, the question remains of how multiple events will influence prospective memory performance. In our experiments, people delivered messages from store to store in a virtual shopping mall as an ongoing task. The prospective tasks were to do certain activities in certain stores. For Experiment 1, each trial involved one prospective memory task to be done in a single location at one of three delays. The virtual environment and location cues were effective for prospective memory, and performance was unaffected by delay. For Experiment 2, each trial involved two prospective memory tasks, given in either one or two instruction locations, and to be done in either one or two store locations. There was improved performance when people received instructions from two locations and did both tasks in one location relative to other combinations. This demonstrates that location-based event structure influences how well people perform on prospective memory tasks.

Comparing time-based and event-based prospective memory over short delays

The current study compared monitoring in time- and event-based prospective memory (PM). Time- and event-based non-focal task instructions were given after a baseline block of a lexical decision ongoing task. Delay between instruction and presentation of PM cue/time was manipulated between-subjects to examine monitoring across short delays (1-6 min). Longer delays decreased performance in the event-based task, but not in the time-based task. This accuracy decline was accompanied by a decline in monitoring (as measured by PM cost to the ongoing task in the trials immediately before the PM cue was presented) between the 1 and 3 min delays. Monitoring was only evident for the time-based task at the 6 min delay as measured by PM cost to the ongoing task. Clock checks were also not affected by delay, but did increase in frequency as the response time neared. These results suggest that delay from the time of intention formation decreases both accuracy and monitoring in event-based tasks, but does not decrease accuracy or monitoring in time-based tasks.

The Dynamic Interplay Between Bottom-Up and Top-Down Processes Supporting Prospective Remembering

Like many dual process theories in the psychological sciences, existing models of prospective memory (i.e., remembering to execute future intentions) emphasize the role of singular top-down or bottom-up processes that act in isolation. We argue that top-down and bottom-up processes are interconnected and dynamically interact to support prospective memory. We elaborate on this dynamic multiprocess framework by focusing on recent behavioral, neuroimaging, and eye-tracking research that demonstrated the dynamic nature of monitoring (top-down) and spontaneous retrieval (bottom-up) processes in relation to contextual factors, metacognition, and individual differences. We conclude that identifying how dual processes interact with environmental and individual difference factors is crucial for advancing understanding of cognition and behavior.