Discrepancy-plus-search processes in prospective memory retrieval

In the present study, we investigated the processes underlying prospective memory (PM) retrieval, focusing specifically on two possible spontaneous processes: discrepancy-plus-search and familiarity. Discrepancy was elicited by orthogonally manipulating the processing difficulties of the PM targets and the nontargets. Participants performed a PM task while solving anagrams with two levels of difficulty (easy or difficult). Assuming that the ease of processing easy anagrams would heighten a sense of familiarity, the familiarity view predicted better PM performance with easy anagrams as the PM targets. In contrast, the discrepancy-plus-search view predicted higher PM performance for the PM targets that were anagrams whose difficulty level mismatched that of the surrounding nontargets, as compared to PM targets whose difficulty matched that of the surrounding nontargets. This prediction was based on the idea that mismatching rather than matching difficulty levels would create discrepancy, thereby signaling significance for the target. Participants were more likely to perform the PM task for PM targets that were discrepant, supporting the discrepancy-plus-search view.     

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.     

When remembering the past suppresses memory for future actions

Remembering planned actions at the correct time in the future is an integral component of prospective cognition. Recent studies on future remembering have led to suggestions that prospective cognition might be based on past experience. To test this hypothesis, we focused on retrieval-induced forgetting (RIF), which usually indicates that remembering past events suppresses memory for related but different past events. The current study assessed RIF in two kinds of event-based prospective memory (PM) tasks using either focal or non-focal cues for ongoing tasks. Participants studied six members from each of eight taxonomic categories and then practiced recalling three of the six members from four of the eight categories using category-stem cues. This retrieval practice suppressed the detection of non-practiced members of the practiced categories during the PM task with non-focal cues (Experiment 1) but not with focal cues (Experiment 2). The results suggest that recall of certain items inhibits the function of the others as PM cues, but only if the PM task does not largely share its processing with the ongoing task.     

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.     

Commission errors in delay–execute prospective memory tasks

Individuals frequently retrieve an intention, but the execution of the task needs to be delayed due to ongoing task demands - so-called delay-execute prospective memory (PM) tasks. We investigated commission errors in the delay-execute paradigm. Participants were told that a PM task is finished (PM task has been executed and is now finished for a final phase) or cancelled (PM task has been cancelled immediately after introduction). We observed commission errors and ongoing task performance in the final phase which included several irrelevant PM cues. In two experiments, we observed significantly more commission errors for cancelled compared to the finished intentions. In Experiment 2, commission errors were eliminated if the final phase required divided attention, regardless of PM task status. In addition, we observed significantly more PM cue interference on the ongoing task in the cancelled compared to the finished group, indicating that the PM task was retrieved in the cancelled group but not in the finished group. As retrieval and execution of the PM task were separated by a delay, the results indicate that commission errors are not always the result of a quick, spontaneous retrieval-execution sequence and may also occur when retrieval and execution are temporally separated.     

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.     

Prior task experience and comparable stimulus exposure nullify focal and nonfocal prospective memory retrieval differences

We explored the nature of focal versus nonfocal event-based prospective memory retrieval. In the context of a lexical decision task, people received an intention to respond to a single word (focal) in one condition and to a category label (nonfocal) for the other condition. Participants experienced both conditions, and their order was manipulated. The focal instruction condition was a single word presented multiple times. In Experiment 1, the stimuli in the nonfocal condition were different exemplars from a category, each presented once. In the nonfocal condition retrieval was poorer and reaction times were slower during the ongoing task as compared to the focal condition, replicating prior findings. In Experiment 2, the stimulus in the nonfocal condition was a single category exemplar repeated multiple times. When this single-exemplar nonfocal condition followed in time the single-item focal condition, focal versus nonfocal performance was virtually indistinguishable. These results demonstrate that people can modify their stimulus processing and expectations in event-based prospective memory tasks based on experience with the nature of prospective cues and with the ongoing task.     

The effects of search criteria and retrieval cue availability on memory for words

The effects of search criteria upon recall performance following a word classification task were investigated. Rival hypotheses were tested, one based on the number of cues available at retrieval and the other on the amount of processing carried out during classification. After being presented with two-component category names, subjects classified words on the basis of either category membership or the number of semantic components the words shared with a target category, and then they received an unexpected recall test. Experiment 1 favored an amount-of-processing explanation, but it was felt that redundancy in the stimulus materials might invalidate this conclusion. Experiment 2 confirmed this suspicion and clearly supported an explanation in terms of retrieval cue availability. The notion of partial semantic processing of words is discussed, and it is argued that the number of congruent encodings formed during classification can be used as an index of elaboration and subsequent memory performance.     

前瞻记忆需要经过策略加工:来自眼动的证据

基于视觉搜索范式,采用多目标刺激呈现的眼动测量方法探索事件性前瞻记忆的加工过程。行为结果显示,对靶目标以及干扰目标的击中率比前瞻记忆目标的击中率均更高,只有前瞻线索和干扰目标比只有靶目标的反应时更长。眼动结果显示,第一注视时间和总注视时间从干扰目标、靶目标到前瞻目标逐渐增长,在前瞻漏报中存在注视到前瞻线索的可能性,搜索序列中靶目标的存在会干扰对前瞻线索的注意。行为和眼动的结果表明,前瞻线索是否被注视到并不会决定前瞻记忆是否会成功,对于意向的实现需要目标检查或者预备注意加工过程,支持策略控制理论。     

Effects of context expectation on prospective memory performance among older and younger adults

This experiment examined the impact of context expectation on prospective memory (PM) performance among older and younger adults. Participants responded to PM target words embedded in an ongoing lexical decision task (LDT). Older and younger adults performed similarly on the PM task. Regardless of age, PM was significantly better for participants in the correct context expectation condition and significantly worse in the incorrect context expectation condition relative to participants who held no expectations about the context in which targets would appear. Participants’ LDT response latencies were used to assess cost of the PM task to the ongoing task. Latencies were discernibly longer in the LDT block where the PM targets were expected compared to the block where they were not expected. The findings provide new information about how context can be used to support PM aging and suggest that contextual information can be equally beneficial for older and younger adults.     

进行中任务加工类型对前瞻记忆TAP效应的影响

该研究采用基于双重任务的实验研究范式,采用双字词作为实验材料,考察了知觉和语义两种进行中任务加工类型对前瞻记忆TAP效应的影响。结果发现：进行中任务加工类型对前瞻记忆绩效的TAP效应有显著影响。当进行中任务为知觉加工时,前瞻记忆任务的绩效存在显著的TAP效应;当进行中任务为语义加工时,前瞻记忆任务绩效的TAP效应没有出现。     

Context-specific prospective-memory processing: Evidence for flexible attention allocation adjustments after intention encoding

Prospective memory (PM) is remembering to fulfill intentions in the future. Interference of unfulfilled intentions with ongoing activities reflects the allocation of attention to the PM task. Prior research has shown that, when people know in which specific context PM cues will occur, attention allocation is adaptive, with slower responses in the PM-relevant context. We examined whether people flexibly adjust their attention allocation when the PM–context association is unknown at intention encoding and must be learned on-task. Different stimulus shapes represented contexts in an ongoing task, with PM cues only occurring in trials with one specific shape. Participants informed about the PM-relevant shape responded more slowly on trials with this shape. Participants instructed that only one, unspecified shape was PM-relevant learned the PM–context association and also allocated attention flexibly, depending on context relevance. However, participants with no context-related information at intention encoding failed to learn the PM–context association, resulting in inflexible attention allocation and poorer PM performance. The present study provides evidence that people can flexibly update their attention-allocation policy, and thereby optimize their PM performance after initial intention encoding, but self-guided learning of intention–context associations appears to be limited.     

基于事件的前瞻记忆与认知控制

前瞻记忆和认知控制是人类认知能力的重要组成部分。Bugg等人(2013)发现前瞻记忆多重加工模型和双重认知控制理论具有共性。此后,越来越多的研究者关注认知控制在意图执行中和执行完成后的作用。本文对近年来关于前瞻记忆与认知控制的研究进行了梳理,发现认知控制对前瞻记忆的完成起支持作用,但二者也在脑机制层面存在差异。本研究能为未来更深入地探讨前瞻记忆的加工机制及生理基础提供新的视角。     

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。     

负性情绪对不同语义、空间关系联结记忆的影响

以负性项目-中性场景以及中性项目-中性场景组成的图片对为材料,通过操控项目-场景之间的语义联系和空间距离,考察了负性情绪对不同语义、空间关系联结记忆的影响。结果显示,当项目-场景空间距离较近时,无论项目-场景之间的语义是否相关,负性情绪始终不会影响项目-场景联结记忆;当项目-场景空间距离较远且语义不相关时,负性情绪会削弱项目-场景联结记忆;而当项目-场景空间距离较远且语义相关时,负性情绪会促进项目-场景联结记忆。结果表明,负性情绪对项目-场景联结记忆的影响会受到项目与场景之间语义关系和空间关系的调节,且语义关系在项目-场景空间距离较远时的作用更为突出。     

On the automatic nature of the task-appropriate processing effect in event-based prospective memory

This research tested competing predictions about the cognitive processes underlying the task-appropriate processing effect in prospective memory. Participants had to press a designated key whenever a word from the semantic category of animals or from the structural category of palindromes occurred in an ongoing lexical decision task. The availability of attentional resources was manipulated by varying the effort to the ongoing task in terms of speed or accuracy. In the task-appropriate semantic prospective memory task, performance was robust against the speed versus accuracy instructions. In the task-inappropriate structural prospective memory task, performance declined under speed instructions that detracted attentional resources. Accordingly, a facilitating effect of task-appropriate processing was observed under speed instructions but not accuracy instructions. The results support the notion that the task-appropriate processing effect is due to a larger contribution of automatic cue detection to prospective memory performance under task-appropriate than task-inappropriate conditions.     

绝对重要性和认知负荷影响基于事件的前瞻记忆

操作前瞻记忆任务的重要性的方式有两种,研究发现相对重要性会造成进行中任务的损耗,而绝对重要性的研究较少且结果不尽一致,这种差异可能与进行中任务占用认知资源的情况有关。我们使用绝对重要性的指导语来操纵前瞻记忆任务的重要性高或者低,并且以Stroop任务作为进行中任务,来考察绝对重要性和认知资源占用的交互影响。结果发现,在进行中任务一致条件下,绝对重要性的增高促进了进行中任务的完成;而不一致条件下,则会阻碍进行中任务的完成。这说明,进行中任务的认知资源变化与前瞻记忆任务重要性对进行中任务的影响有着交互调节作用。     

前瞻记忆后效的加工机制：对自发提取观点和抑制观点的检验

摘 要 实验1探究前瞻记忆后效的产生是否消耗认知资源,实验2进一步探究前瞻记忆后效产生过程中消耗的认知资源的去向。实验1结果显示在完成阶段,相比于基线条件,其它四种实验条件的进行中任务反应速度均较慢,实验2结果显示无论线索是否显著,前瞻记忆后效均会随着认知负荷的提高而提高。结果表明前瞻记忆后效产生过程中会消耗认知资源对原意向进行抑制。本研究支持了抑制的观点。     

The role of temporal delay and repeated prospective memory cue exposure on the deactivation of completed intentions

Previous studies have shown that completed prospective memory (PM) intentions entail aftereffects in terms of ongoing-task-performance decrements in trials containing repeated PM cues which previously served as PM cues triggering the intended action. Previous research reported that PM aftereffects decrease over time, thus revealing a specific time course of PM aftereffects. In the present study, we tested two accounts for this pattern, assuming either that the decline of aftereffects is related to the temporal distance to PM task completion or may be a result of the repeated exposure of repeated PM cues in the ongoing task. In three experiments, we manipulated both the temporal distance to PM task completion and the frequency of repeated PM cues and demonstrated that aftereffects of completed intentions declined with repeated exposure of formerly relevant PM cues. In addition, effects of repeated exposure were not only limited to the repetition of specific PM-cue exemplars but also generalized to other semantically related PM cues within the PM-cue category. Together, findings show that decreased aftereffects of completed intentions are not related to the temporal duration of the subsequent test block, but crucially depend on the repeated exposure of the previously relevant PM cues.     

The impact of retrieval suppression on conceptual implicit memory

ABSTRACT

When people suppress retrieval of episodic memories, it can induce forgetting on later direct tests of memory for those events. Recent reports indicate that suppressing retrieval affects less conscious, unintentional retrieval of unwanted memories as well, at least on perceptually-oriented indirect tests. In the current study we examined how suppressing retrieval affects conceptual implicit memory for the suppressed content, using a category verification task. Participants studied cue-target words pairs in which the targets were exemplars of 22 semantic categories, such as vegetables or occupations. They then repeatedly retrieved or suppressed the targets in response to the cues for some of those pairs. Afterwards, they were exposed to the targets intermixed with novel items, one at a time, and asked to verify the membership of each of the words in a semantic category, as quickly as possible. Judgment response times to studied words were faster than to unstudied exemplars, reflecting repetition priming, as has been previously observed. Strikingly, the beneficial effects of prior exposure on response time were eliminated for targets that had been suppressed. Follow-up explicit memory tests also demonstrated that retrieval suppression continued to disrupt episodic recall for the items that had been just been re-exposed on the category verification test. These findings support the contention that the effects of retrieval suppression are not limited to episodic memory, but also affect indirect expressions of those memories on conceptually oriented tests, raising the possibility that underlying semantic representations of suppressed content are affected.