Prospective Memory Retrieval Research Articles

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.

Prospective memory and what costs do not reveal about retrieval processes: A commentary on Smith, Hunt, McVay, and McConnell (2007).

On the basis of consistently finding significant overall costs to the ongoing task with a single salient target event, Smith, Hunt, McVay, and McConnell (2007) concluded that preparatory attentional processes are required for prospective remembering and that spontaneous retrieval does not occur. In this article, we argue that overall costs are not completely informative in terms of specifying the underlying processes mediating prospective memory retrieval, and we suggest more promising approaches for testing for the existence of these processes. We also argue that counterbalancing in a within-subjects design is one of several proper methods for assessing costs.

Encoding the future: Successful processing of intentions engages predictive brain networks

Evidence from cognitive, patient and neuroimaging research indicates that “remembering to remember” intentions, i.e., prospective memory (PM) retrieval, requires both general memory systems involving the medial temporal lobes and an executive system involving rostral PFC (BA 10). However, it is not known how prospective memories are initially formed. Using fMRI, we investigated whether brain activity during encoding of future intentions and present actions differentially predicted later memory for those same intentions (PM) and actions (retrospective memory). We identified two significant patterns of neural activity: a network linked to overall memory and another linked specifically to PM. While overall memory success was predicted by temporal lobe activations that included the hippocampus, PM success was also uniquely predicted by activations in additional regions, including left rostrolateral PFC and the right parahippocampal gyrus. This finding extends the role of these structures to the formation of individual intentions. It also provides the first evidence that PM encoding, like PM retrieval, is supported by both a common episodic memory network and an executive network specifically recruited by future-oriented processing.

An Assessment of Prospective Memory Retrieval in Women with Chronic Fatigue Syndrome Using a Virtual-Reality Environment: An Initial Study

People with chronic fatigue syndrome (CFS) have increased rates of depression, anxiety, and illness intrusiveness; they may also suffer from cognitive problems such as retrospective memory (RM) deficits and concentration difficulties that can stem from diminished information-processing capability. We predicted that this diminished capacity may also lead to deficits in other cognitive functions, such as prospective memory (ProM). Event-, time-, and activity-based ProM was assessed in 11 women with CFS and 12 healthy women using a computer-generated virtual environment (VE). RM was assessed using a free-recall test, and subjective assessment of both ProM and RM was assessed by questionnaire. Groups were equivalent in age and measures of IQ. People with CFS performed slightly worse than healthy controls on both the event- and time-based ProM measures, although these were not statistically significant. However, the CFS group performed significantly worse than the healthy controls on both the free recall-task and on subjective assessment of both RM and ProM. Women with CFS do have some subtle decrements in memory, particularly RM. However, it is possible that the decrements found in the present sample would be greater in real life. Further studies utilizing both healthy controls and illness controls are now needed to ascertain how sensitive the VE measure is and to inform the development of tasks in the VE that place progressively increasing demands on working memory capacity.

Threat-related processing supports prospective memory retrieval for people with obsessive tendencies

Obsessive-compulsive disorder can result in a variety of deficits to cognitive performance, including negative consequences for attention and memory performance. The question addressed in the current study concerned whether this disorder influenced performance in an event-based prospective memory task. The results from a subclinical population indicated that, relative to non-anxious controls and mildly depressed controls, people with obsessive-compulsive tendencies (washing compulsions) incur decrements in remembering to respond to cues related to a neutral intention (respond to animals). This deficit was ameliorated by giving the subclinical group an intention about a threat-related category (respond to bodily fluids) and cueing them with concepts that they had previously rated as particularly disturbing to them. Thus, their normal attentional bias for extended processing of threat-related information overcame their natural deficit in event-based prospective memory.

Brain regions and their dynamics in prospective memory retrieval: A MEG study

We measured brain activity using magnetoencephalography in five participants during ongoing tasks that included prospective memory, retrospective memory, and oddball trials. Sources were identified in the hippocampal formation and posterior parietal and frontal lobes. Posterior parietal cortex activation had an earlier onset in the prospective memory condition than retrospective memory or oddball conditions, a higher level of theta activity in the retrospective condition, and higher levels of upper alpha in the prospective and oddball conditions. Activation of the hippocampal formation had a longer duration in the retrospective memory and prospective memory conditions than the oddball condition, but prominent alpha and theta band activity was present in all three conditions. We interpret the early (87 ms) onset of activity in parietal cortex as evidence for an initial noticing of appropriate conditions for a PM response. Hippocampal activity may reflect a subsequent memory search for the intended action.

The role of noticing in prospective memory forgetting

Two experiments used autonomic reactions (i.e., skin conductance responses; SCRs) in conjunction with behavioral responses to study retrieval processes in prospective memory. SCRs were recorded while participants performed a prospective memory task embedded in an ongoing task. Stimuli that received the same behavioral response (i.e., no prospective memory response) evoked different autonomic reactions as a function of whether they were versus were not prospective cues (Experiments 1 and 2) and as a function of whether they did versus did not share perceptual or conceptual features with prospective cues (Experiment 2). To the extent that SCRs provide an index of noticing a stimulus, increased SCRs for prospective cues and for stimuli that shared features with prospective cues (even though they were not responded to as prospective cues) provided evidence that noticing a stimulus is not invariably accompanied by recognizing the stimulus as a cue to perform an intended action. The results are consistent with the general 2-stages cue-focused view of prospective memory retrieval, which proposes that noticing a prospective cue prompts a directed memory search, which can result in recognizing the stimulus as a cue to perform an intended action and retrieving the intended action.

Discrepancy processes in prospective memory retrieval

Discrepancy processes may be helpful in noticing prospective memory targets (McDaniel, Guynn, Einstein, & Breneiser, 2004). We manipulated the discrepancy of prospective memory targets from the processing coherence established by the ongoing task by preexposing nontarget items in the ongoing task either five times (high discrepancy) or two times (low discrepancy). Prospective memory performance was significantly better in the high-discrepancy group than in the low-discrepancy group. These results support a discrepancy view of prospective remembering.

A Model for Integrating Elementary Neural Functions into Delayed-Response Behavior

It is well established that various cortical regions can implement a wide array of neural processes, yet the mechanisms which integrate these processes into behavior-producing, brain-scale activity remain elusive. We propose that an important role in this respect might be played by executive structures controlling the traffic of information between the cortical regions involved. To illustrate this hypothesis, we present a neural network model comprising a set of interconnected structures harboring stimulus-related activity (visual representation, working memory, and planning), and a group of executive units with task-related activity patterns that manage the information flowing between them. The resulting dynamics allows the network to perform the dual task of either retaining an image during a delay (delayed-matching to sample task), or recalling from this image another one that has been associated with it during training (delayed-pair association task). The model reproduces behavioral and electrophysiological data gathered on the inferior temporal and prefrontal cortices of primates performing these same tasks. It also makes predictions on how neural activity coding for the recall of the image associated with the sample emerges and becomes prospective during the training phase. The network dynamics proves to be very stable against perturbations, and it exhibits signs of scale-invariant organization and cooperativity. The present network represents a possible neural implementation for active, top-down, prospective memory retrieval in primates. The model suggests that brain activity leading to performance of cognitive tasks might be organized in modular fashion, simple neural functions becoming integrated into more complex behavior by executive structures harbored in prefrontal cortex and/or basal ganglia.

Multiple Processes in Prospective Memory Retrieval: Factors Determining Monitoring Versus Spontaneous Retrieval.

Theoretically, prospective memory retrieval can be accomplished either by controlled monitoring of the environment for a target event or by a more reflexive process that spontaneously responds to the presence of a target event. These views were evaluated in Experiments 1-4 by examining whether performing a prospective memory task produced costs on the speed of performing the ongoing task. In Experiment 5, the authors directly tested for the existence of spontaneous retrieval. The results supported the multiprocess theory (M. A. McDaniel & G. O. Einstein, 2000) predictions that (a) spontaneous retrieval can occur and can support good prospective memory and (b) depending on task demands and individual differences, people rely to different degrees on monitoring versus spontaneous retrieval for prospective remembering.

Neural correlates of prospective and retrospective memory

This study examines the event-related brain potential (ERP) correlates of retrieval processes in prospective and retrospective memory (i.e., recognition and cued-recall). In contrast to previous research that has compared performance on tasks measuring prospective and retrospective memory, the stimulus materials and encoding and response demands of the prospective and retrospective components of the tasks were reasonably well matched for the two forms of memory. This resulted in the primary difference between the assessments of prospective and retrospective memory being the requirement for self-initiated retrieval in prospective memory. Analyses of mean amplitude measures revealed modulations of the ERPs typically associated with prospective memory (i.e., N300 and prospective positivity) and retrospective memory (i.e., FN400, parietal positivity and frontal slow waves). Partial least squares analyses revealed one latent variable related to the retrieval of a previously studied item that contrasted retrospective hits and prospective hits from ongoing activity trials and prospective lures; and one latent variable uniquely associated with prospective hits. These findings indicate that similar neural processes support retrieval in prospective and retrospective memory and that the realization of intentions is additionally dependent on processes that are uniquely related to prospective memory.

Assessing stroke patients’ prospective memory using virtual reality

There is a dearth of empirical evidence about prospective memory (remembering to perform actions in the future) in stroke patients. A probable reason for this is that it is difficult to perform a realistic and controlled assessment of prospective memory ability in a rehabilitation setting. Virtual reality may provide a solution to this difficulty by allowing prospective memory to be tested in a simulation of a real-life situation whilst retaining a laboratory level of scientific control. This exploratory study assessed the performance of stroke patients and age-matched control participants on event-, time- and activity-based prospective memory retrieval tasks in a personal computer-based virtual environment. Stroke patients were severely impaired at the event- and activity-based tasks compared with age-matched controls, but only marginally impaired at the time-based task. The additional knowledge gained from this form of assessment could direct rehabilitation more effectively towards specific impairments of individual patients.

A two‐process model of strategic monitoring in event‐based prospective memory: Activation/retrieval mode and checking

Theorists have suggested that individuals may remember to execute event‐based intended actions by deploying executive or attentional resources to monitor for the markers or target events that indicate that it is appropriate to execute the intended actions (e.g., McDaniel & Einstein, 2000; Shallice & Burgess, 1991), but these strategic monitoring views are not specific about the processes that strategic monitoring entails. A more specific idea is outlined here (see also Guynn, 2001) and an experiment with results consistent with this view is reported. According to this two‐process view, strategic monitoring entails maintaining the cognitive system in a prospective memory retrieval mode, which may be mediated by increased activation of the prospective memory representation, plus checking whether the circumstances to execute the intended action are present. In the current experiment, concurrent task impairment on nontarget trials, on which participants were instructed to press a key if they saw a target event (i.e., experimental trials), relative to trials on which participants were not instructed to press a key if they saw a target event (i.e., control trials), provided a footprint of strategic monitoring. An interaction of trial type and whether the experimental and control trials alternated or were blocked revealed greater impairment on experimental trials relative to control trials when the trials were blocked than when the trials alternated. Performance on experimental trials did not vary whether the trials alternated or were blocked, while performance on control trials was significantly worse when the trials alternated than when the trials were blocked. The results are consistent with the two‐process view and the idea that participants maintained a retrieval mode/activation and checked on experimental trials, neither maintained a retrieval mode/activation nor checked on blocked control trials, and maintained a retrieval mode/activation but did not check on alternating control trials.

Strategic and automatic processes in prospective memory retrieval: a multiprocess framework

AbstractProspective memory situations involve forming intentions and then realizing those intentions at some appropriate time in the future. An interesting feature of most prospective remembering is that recollection of the intended action occurs without an explicit request to attempt retrieval, and we present two views on how this type of remembering can be accomplished. One could strategically monitor the environment for the presence of the target event, or one could rely on anticipated environmental conditions more or less automatically reinstating the intended action. We present data supporting both views and argue that people use multiple approaches for solving the problem of retrieving an intention (prospective memory) after a delay. Moreover, we suggest that the extent to which prospective remembering is supported by relatively automatic processes (versus strategic resource‐demanding monitoring) and the probability with which prospective memory is likely to be successful when relying on automatic processes varies as a function of the characteristics of the prospective memory task, target cue, ongoing task, and individual. We argue that the complexity of the empirical findings can best be understood by appealing to this multiprocess view of prospective memory. Copyright © 2000 John Wiley & Sons, Ltd.

Encoding Modality and Prospective Memory in Children

In three experiments, we investigated the effects of different cue encoding modalities on young and older children's prospective memory. In Experiments 1 and 2, younger subjects showed the highest performance when the cue prompting the action was visually presented, whereas older children's performance benefited from enactment of the response. However, results from Experiment 3 showed that, under conditions which emphasise the link between the cue and the action to be performed, even younger children's memory benefits from motoric enactment of the response. These results are discussed in terms of the development of specific integration processes necessary for prospective memory retrieval.