Wait a second: Brief delays in responding reduce focality effects in event-based prospective memory

Remembering to perform deferred actions when an event is encountered in the future is referred to as event-based prospective memory (PM). We examined whether the failure of individuals to allocate sufficient attentional resources to nonfocal PM tasks can be linked to the response demands inherent in PM paradigms that require the PM task to race for response selection with the speeded ongoing task. In three experiments, participants performed a lexical decision task while being required to make a separate PM response to a specific word (focal), an exemplar of a category (nonfocal), or a syllable (nonfocal). We manipulated the earliest time participants could make task responses by presenting a tone at varying onsets (0–1,600 ms) following stimulus presentation. Improvements in focal PM and nonfocal PM were observed at response delays as brief as 200 ms and 400 ms, respectively. Nonfocal PM accuracy was comparable to focal PM accuracy at delays of 600 ms and 1,600 ms for categorical targets and syllable targets, respectively. Delaying task responses freed the resource-demanding processing operations used on the ongoing task for use on the nonfocal PM task, increasing the probability that the nonfocal PM features of ongoing task stimuli were adequately assessed prior to the ongoing task response.     

Intraindividual reaction time variability predicts prospective memory failures in older adults

This study investigated the relationship between intraindividual variability (IIV) in reaction time and prospective memory errors in older adults using data from the Zurich Longitudinal Study of Cognitive Aging (n = 336 individuals aged 66–81 years). The results indicated that increased IIV measured from independent tasks was associated with a greater proportion of prospective memory errors. These significant findings were not influenced by age and did not vary according to prospective memory cue type. Variability is thought to reflect fluctuations in attentional and executive control and these attentional processes may also impact on prospective memory through failure to detect the target cue. The findings suggest, therefore, that measures of variability may have some potential in the identification of older persons who are more vulnerable to everyday errors such as prospective memory failures.     

Enhanced recognition of words previously presented in a task with nonfocal prospective memory requirements

Remembering to perform deferred actions when events are encountered in the future is referred to as event-based prospective memory. Individuals can be slower to respond to ongoing tasks when they have prospective memory task requirements. These costs are interpreted as evidence for cognitive control processes allocated to the prospective memory task, but we know little about these processes. In the present article, the recognition of nontargets previously presented in an ongoing task with prospective memory task requirements provided evidence for the differential processing of individual ongoing task items. Participants performed a lexical decision task, where some participants were required to make an alternative prospective memory response either to a specific word (focal) or to exemplars of a category (nonfocal). Participants were slower to respond to the ongoing task in the nonfocal conditions than in the control condition (costs), regardless of whether or not prospective memory task importance was emphasized. Participants were also slower to respond to the ongoing task in the focal conditions than in the control condition, but only when prospective memory task importance was emphasized. This task was followed by a surprise recognition memory test in which nontarget words from the lexical decision task were intermixed with new words. Focal conditions, but not nonfocal conditions, showed better discrimination on the recognition task, as compared with the control condition. Participants in nonfocal conditions mapped the semantic features of the ongoing task letter strings onto the semantic features of their prospective memory category, and this elaboration in the processing of individual nontargets increased incidental learning and produced the recognition benefit.     

MPT模型在事件性前瞻记忆研究中的应用

前瞻性记忆是指对将要进行的活动或事件的记忆。前瞻记忆中,包含了前瞻成分和回溯成分。前人研究中,缺乏对前瞻成分和回溯成分有效的分离手段,使得对前瞻记忆机制的探讨缺乏深入挖掘。本文将MPT模型与Cohen等人的研究范式对比,分析了该模型在事件性前瞻记忆研究中的优势。文章对模型的理论基础,模型的主要内容,模型的数据计算方法,模型的效度以及模型的应用等几个方面进行了介绍,同时对模型使用中需要注意的问题进行了讨论。     

Cognitive control processes underlying time-based prospective memory impairment in individuals with high depressive symptomatology

The current study compared time-based prospective memory (PM) for individuals with high depressive symptomatology (HDS) and low depressive symptomatology (LDS). We examined PM accuracy rate, clock-checking frequency, and decrements in ongoing task performance (i.e., costs to ongoing tasks) associated with an embedded time-based PM task. HDS participants demonstrated numerically lower but statistically comparable clock-checking frequency to LDS participants. However, their PM performance was significantly poorer than that of LDS participants. The pattern of observed costs to ongoing tasks and correlational analyses between ongoing task performance and PM accuracy showed that, relative to LDS participants, HDS participants were restricted in their allocation of attentional resources to support PM. We concluded that although HDS and LDS participants externally controlled their time-based PM task performance (i.e., clock-checking) similarly, the HDS participants lacked the cognitive initiative to allocate attentional resources to internally control PM task performance. Such internal control might reflect time-estimation processes, the resources required to maintain the PM task response intention, and/or the ability to coordinate the PM task response with ongoing task demands. To our knowledge, this is the first paper to have examined time-based PM strategies used by HDS individuals beyond clock-checking. The data suggest that interventions that encourage intermittent strategic reviews of PM goals may be beneficial for individuals with high depressive symptomatology.     

The interplay of intention maintenance and cue monitoring in younger and older adults’ prospective memory

The retention phase of a prospective memory (PM) task poses different challenges, including demands to store or maintain an intended action and to realize the right moment for action execution. The interplay of these processes in younger and older adults has not been explored so far. In this study, the authors examined the impact of maintenance load and task focality on PM in 84 younger and in 83 older adults. Results indicated that PM performance and ongoing task response times were strongly affected by maintenance load and age. However, a focality effect only emerged when maintenance load was low but not when attentional resources were deployed for maintaining a more demanding intention. These findings suggest that maintenance and monitoring requirements compete for similar attentional resources. Furthermore, maintenance load may affect postretrieval processes through its impact on working-memory resources, which can restrain the typical advantage of focal over nonfocal PM tasks.     

Age, Focal Processing, and Monitoring in Event-Based Prospective Memory

While there is some consensus that prospective memory (PM) declines with age, the reasons for differences in performance across age groups are not fully understood. This experiment examines two factors that are likely to affect the magnitude of observed age group differences: type of PM task and whether participants monitor the task environment for the opportunity to complete the PM task. Younger and older adults were engaged in an ongoing test of short-term memory and were asked to perform one of two different event-based PM tasks. Younger adults performed better than older adults on both focal and nonfocal PM tasks. In addition, younger adults were able to perform both types of tasks equally well, but older adults were more successful on the focal task than on the nonfocal task. Age group differences in self-reported PM monitoring were also evident and were related to performance. These findings and their implications for current theoretical conceptions of PM aging are discussed.     

Effects of delay of prospective memory cues in an ongoing task on prospective memory task performance

To address the mixed results reported in previous studies, the present experiments examined forgetting in prospective memory (PM) by manipulating the delay between the PM instructions and cue presentation in event-based PM tasks. PM performance was measured for delays of 2–20 min in Experiment 1 and for delays of approximately 1–10 min in Experiment 2. Experiment 2 included both focal and nonfocal PM tasks, and speed on the ongoing task was measured to examine evidence for monitoring processes across the delays tested. The results suggest that nonfocal PM performance follows a nonlinear forgetting function (i.e., rapid decline for shorter delays and slower decline for longer delays) when tested over delays from 1 to 20 min. No effect of delay was seen for the focal task tested in Experiment 2 from 1 to 10 min. In Experiment 2, ongoing-task costs were also found for the first delay but not for longer delays, suggesting that monitoring was significantly reduced between 1 and 2.5 min of the ongoing-task trials.     

Prospective memory performance across adolescence

In the present study, the authors explored age differences in event-based prospective memory (PM) across adolescence. The tasks consisted of an ongoing task (OT; i.e., personality questionnaire items, math problems) and an embedded prospective task that required participants to remember to make a special response whenever they encountered a PM cue (i.e., a negative word in the OT). The 341 participants (aged 13-22 years) revealed a significant main effect of age, which indicated better PM performance of young adults compared with teenagers. Moreover, when emphasizing the OT versus the PM task, teenagers' PM profited from PM emphasis more than did young adults' PM. The authors discuss the data in the context of limited executive capacity as a factor influencing cognitive development across adolescence.     

Prospective memory: Are preparatory attentional processes necessary for a single focal cue?

The preparatory attentional and memory processes theory of prospective memory (PM) assumes that PM retrieval requires resource-demanding preparatory attentional processes, whereas the multiprocess theory assumes that retrieval can also occur spontaneously. On the basis of showing slowing on an ongoing task (i.e., task interference) —even when the PM cue was highly salient (i.e., the participant’s own name) —Smith, Hunt, McVay, and McConnell (2007) concluded that preparatory attentional processes are always necessary for PM retrieval. We argue that the presence of preparatory attentional processes cannot be used to rule out the existence of spontaneous retrieval processes, and the goal of the present research was to examine whether PM retrieval can occur in the absence of preparatory attentional processes. We varied whether we emphasized the importance of the PM task or the ongoing task, and we assessed task interference across quarters of the ongoing task. Our results showed no evidence of task interference and, hence, no evidence of preparatory attentional processes in the periods proximal to the target event, and yet participants showed high PM performance. Thus, the results suggest the existence of spontaneous retrieval processes and support the multiprocess theory.     

Evidence for a detrimental relationship between hypertension history, prospective memory, and prefrontal cortex white matter in cognitively normal older adults

Hypertension affects many older adults and is associated with impaired neural and cognitive functioning. We investigated whether a history of hypertension was associated with impairments to prospective memory, which refers to the ability to remember to perform delayed intentions, such as remembering to take medication. Thirty-two cognitively normal older adult participants with or without a history of hypertension (self-reported) performed two laboratory prospective memory tasks, one that relied more strongly on executive control (nonfocal prospective memory) and one that relied more strongly on spontaneous memory retrieval processes (focal prospective memory). We observed hypertension-related impairments for nonfocal, but not focal, prospective memory. To complement our behavioral approach, we conducted a retrospective analysis of available structural magnetic resonance imaging data. Lower white matter volume estimates in the anterior prefrontal cortex were associated with lower nonfocal prospective memory and with a history of hypertension. A history of hypertension may be associated with worsened executive control and lower prefrontal white matter volume. The translational implication is that individuals who must remember to take antihypertensive medications and to monitor their blood pressure at home may be impaired in the executive control process that helps to support these prospective memory behaviors.     

Individual differences in event-based prospective memory: Evidence for multiple processes supporting cue detection

The multiprocess view proposes that different processes can be used to detect event-based prospective memory cues, depending in part on the specificity of the cue. According to this theory, attentional processes are not necessary to detect focal cues, whereas detection of nonfocal cues requires some form of controlled attention. This notion was tested using a design in which we compared performance on a focal and on a nonfocal prospective memory task by participants with high or low working memory capacity. An interaction was found, such that participants with high and low working memory performed equally well on the focal task, whereas the participants with high working memory performed significantly better on the nonfocal task than did their counterparts with low working memory. Thus, controlled attention was only necessary for detecting event-based prospective memory cues in the nonfocal task. These results have implications for theories of prospective memory, the processes necessary for cue detection, and the successful fulfillment of intentions.     

Context cue focality influences strategic prospective memory monitoring

Monitoring the environment for the occurrence of prospective memory (PM) targets is a resource-demanding process that produces cost (e.g., slower responding) to ongoing activities. However, research suggests that individuals are able to monitor strategically by using contextual cues to reduce monitoring in contexts in which PM targets are not expected to occur. In the current study, we investigated the processes supporting context identification (i.e., determining whether or not the context is appropriate for monitoring) by testing the context cue focality hypothesis. This hypothesis predicts that the ability to monitor strategically depends on whether the ongoing task orients attention to the contextual cues that are available to guide monitoring. In Experiment 1, participants performed an ongoing lexical decision task and were told that PM targets (TOR syllable) would only occur in word trials (focal context cue condition) or in items starting with consonants (nonfocal context cue condition). In Experiment 2, participants performed an ongoing first letter judgment (consonant/vowel) task and were told that PM targets would only occur in items starting with consonants (focal context cue condition) or in word trials (nonfocal context cue condition). Consistent with the context cue focality hypothesis, strategic monitoring was only observed during focal context cue conditions in which the type of ongoing task processing automatically oriented attention to the relevant features of the contextual cue. These findings suggest that strategic monitoring is dependent on limited-capacity processing resources and may be relatively limited when the attentional demands of context identification are sufficiently high.     

Executive functioning and prospective memory in young children

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

Disruptions of preparatory attention contribute to failures of prospective memory

In two experiments, we examine the efficacy of preparatory attentional processes and intention superiority as explanations of the finding that response time (RT) for prospective memory (PM) cue misses is often faster than that for ongoing activity trials or PM cue hits. RT was faster for prospective misses than for ongoing activity trials, demonstrating an intention superiority effect. RT was also faster for ongoing activity trials preceding prospective misses than for those preceding prospective hits. We interpret this finding as reflecting variation in the efficiency of preparatory attentional processes during task performance, leading to failures of PM when preparatory attentional processes are suboptimal.     

Performance predictions affect attentional processes of event-based prospective memory

To investigate whether making performance predictions affects prospective memory (PM) processing, we asked one group of participants to predict their performance in a PM task embedded in an ongoing task and compared their performance with a control group that made no predictions. A third group gave not only PM predictions but also ongoing-task predictions. Exclusive PM predictions resulted in slower ongoing-task responding both in a nonfocal (Experiment 1) and in a focal (Experiment 2) PM task. Only in the nonfocal task was the additional slowing accompanied by improved PM performance. Even in the nonfocal task, however, was the correlation between ongoing-task speed and PM performance reduced after predictions, suggesting that the slowing was not completely functional for PM. Prediction-induced changes could be avoided by asking participants to additionally predict their performance in the ongoing task. In sum, the present findings substantiate a role of metamemory for attention-allocation strategies of PM.     

线索聚焦性影响前瞻记忆意向维持与提取：来自眼动追踪的证据

研究以眼动追踪的方法探讨线索聚焦性对前瞻记忆(prospective memory, PM）加工过程的影响。实验1中,28名被试完成了线索聚焦和非聚焦两类PM眼动追踪任务。结果发现,个体在聚焦和非聚焦两类PM任务意向维持、意向提取阶段上均表现出不同的眼动加工特征。实验2中,研究进一步对线索聚焦和非聚焦两个PM任务中PM线索词重复次数进行平衡,并重复了实验1的研究结果,说明实验1所观测到的效应不是PM线索词重复造成的混淆,线索聚焦性影响PM的意向维持、意向提取过程,研究结果支持多重加工理论。     

Differential recruitment of executive resources during mind wandering

Recent research has shown that mind wandering recruits executive resources away from the external task towards inner thoughts. No studies however have determined whether executive functions are drawn away in a unitary manner during mind wandering episodes, or whether there is variation in specific functions impacted. Accordingly, we examined whether mind wandering differentially modulates three core executive functions—response inhibition, updating of working memory, and mental set shifting. In three experiments, participants performed one of these three executive function tasks and reported their attentional state as either on-task or mind wandering at random intervals. We found that mind wandering led to poorer performance in the response inhibition and working memory tasks, but not the set-shifting task. These findings suggest that mind wandering does not recruit executive functions in a monolithic manner. Rather, it appears to selectively engage certain executive functions, which may reflect the adaptive maintenance of ongoing task performance.     

Age-related effects in prospective memory are modulated by ongoing task complexity and relation to target cue

Two experiments examined the puzzling variation in the age-related patterns for event-based prospective memory tasks. Both experiments involved a famous faces ongoing task with a feature of the famous face as the target for the prospective memory task. In Experiment 1, a substantial age deficit was found on the prospective memory task when the cue was nonfocal (wearing glasses) to the ongoing task, replicating previous research, but this deficit was significantly reduced with a focal cue (first name John). In Experiment 2, the prospective memory cue (wearing glasses) was held constant and the demands of the ongoing task of naming faces were varied. The substantial age differences found with a nonfocal cue were eliminated when the ongoing task was made less challenging. The findings help reconcile the divergent age-related findings reported in the literature.     

How did I remember to do that? Self-reported strategy use for laboratory prospective memory tasks

ABSTRACT

The role of metacognition in prospective memory (PM) has received relatively little attention. This study combined data from several experiments to identify the strategy repertoire employed during a classic laboratory PM task and to determine whether self-reported strategy was related to performance. Participants (N?=?668) completed either a focal or nonfocal PM task embedded in an ongoing lexical decision task. The results indicated that participants reported the same strategy repertoire regardless of PM task focality. Participants who reported using a strategy performed better than those who did not report using one, and this was especially true under nonfocal conditions. Self-reported strategy use was also associated with more cost to the ongoing task when the opportunity to complete the PM task was present. These findings add to what is known about the metacognitive components of PM and underscore the need for additional research in this area.