Fan effects in event-based prospective memory

Three experiments investigated whether event-based prospective memory was affected by the associative fan of the cues to be detected. The associative fan was operationally defined as the number of associates paired with event-based cues in a paired associate learning phase. Subsequent to the paired associate learning, participants were given a lexical decision task in which event-based cues were embedded. The results from Experiments 1 and 2 confirmed that a larger associative fan significantly reduced event-based cue detection. The third experiment confirmed that the absolute strength of an association does not affect performance, rather the number of associations does. As an ancillary issue, the authors tested whether cue detection was affected by the familiarity of the background words used in the lexical decision task. No consistent evidence for a discrepancy plus search model of prospective memory was found.     

Fan effects in event-based prospective memory

Three experiments investigated whether event-based prospective memory was affected by the associative fan of the cues to be detected. The associative fan was operationally defined as the number of associates paired with event-based cues in a paired associate learning phase. Subsequent to the paired associate learning, participants were given a lexical decision task in which event-based cues were embedded. The results from Experiments 1 and 2 confirmed that a larger associative fan significantly reduced event-based cue detection. The third experiment confirmed that the absolute strength of an association does not affect performance, rather the number of associations does. As an ancillary issue, the authors tested whether cue detection was affected by the familiarity of the background words used in the lexical decision task. No consistent evidence for a discrepancy plus search model of prospective memory was found.     

Interrupting intentions: Zeigarnik-like effects in prospective memory

In two experiments, we examined the effects of task interruption on memory for intentions. Participants studied a series of anagrams, of which they solved one-half (Exp. 1) or two-thirds (Exp. 2), whereas the solution of the remaining items was interrupted by the experimenter. Furthermore, four anagrams (prospective cue items) differed from the remaining anagrams in that the third letter of each item was underlined. Participants were instructed to decide whether a subsequently presented (target) anagram contained the same or a different third letter as the underlined letter of the cue item. The results of both experiments showed Zeigarnik-like effects in prospective memory, so that cue items that were associated with interruption in the anagram task were better reminders than were items that were associated with completion. These findings suggest that interruption of an ongoing activity facilitates subsequent prospective memory performance, possibly by increasing the level of activation of the underlying intention representation that, in turn, increases the individual's sensitivity to identify the target event.     

Importance effects on performance in event-based prospective memory tasks

In the present study we manipulated the importance of performing two event-based prospective memory tasks. In Experiment 1, the event-based task was assumed to rely on relatively automatic processes, whereas in Experiment 2 the event-based task was assumed to rely on a more demanding monitoring process. In contrast to the first experiment, the second experiment showed that importance had a positive effect on prospective memory performance. In addition, the occurrence of an importance effect on prospective memory performance seemed to be mainly due to the features of the prospective memory task itself, and not to the characteristics of the ongoing tasks that only influenced the size of the importance effect. The results suggest that importance instructions may improve prospective memory if the prospective task requires the strategic allocation of attentional monitoring resources.     

Varying the importance of a prospective memory task: differential effects across time- and event-based prospective memory

Only few studies have addressed the issue of task importance in prospective memory. Most of them, but not all, have shown that perceived task importance does improve prospective memory performance. However, there is little understanding of (1) the conditions under which importance of the prospective memory task makes a difference in performance and (2) the mechanisms by which perceived task importance has an effect on prospective memory performance. The present study reports two experiments that manipulate task importance in a time-based and an event-based prospective memory paradigm. Results show that importance has an effect on the time-based but not on the event-based task. Further analyses of the performance in the cover tasks as well as the monitoring behaviour indicate that importance improves prospective memory to the degree the task requires the strategic allocation of attentional resources.     

Prospective memory and aging: The effects of working memory and prospective memory task load

Abstract

A person's level of engagement in other actions may influence whether a prospective action is correctly performed. This study used a computerized prospective memory task in which participants remembered to perform an action when a specified background pattern appeared while they simultaneously performed a verbal working memory task. Amount of engagement in the working memory task was manipulated by increasing the number of words to be recalled. Prospective memory load was manipulated by varying the number of prospective targets. Older adults performed more poorly than younger adults on the prospective memory task under higher working memory load and also higher prospective load. Participants with lower working memory load performed better on the prospective task, regardless of age. There were no significant age differences in the absolute accuracy of performance postdictions (post experiment performance awareness). Age differences were also found with a second prospective memory task in which participants were told to write the day of the week (DOW) on the top of answer sheets for tasks performed later in the experiment. No significant correlations were observed between the two prospective memory tasks for either age group.     

Priming and semantic memory loss in Alzheimer's disease

Semantic memory (SM) was investigated in six patients with probable Alzheimer's disease (AD) by on-line measurement of semantic priming in a lexical decision task, and off-line tests of comprehension. Detailed assessment was carried out on naming, name comprehension, and probes of semantic knowledge with a battery of 150 items. The patients performed normally on perceptual tests and displayed an item-specific loss of knowledge on the semantic tests. In a primed lexical decision task, greater semantic priming was found relative to age-matched normals. The priming was substantially greater for items with "degraded" representations as determined by the off-line tests. Lexical decision was also performed more slowly on these items. These unexpected results demand a reevaluation of the concepts of the lexicon and semantic memory structure and their possible alteration in dementia.     

Priming effects in perceptual classification

Priming stimuli that spatially flank a fixated target stimulus may cause either facilitation or interference with target classification, depending on experimental context. Two experiments demonstrated distinct effects of response compatibility and semantic congruity between flankers and target. Response competition occurred when targets were flanked by context stimuli associated with the opposite response, but this effect diminished when the target was delayed relative to the flankers. Facilitative priming by response-compatible flankers, in contrast, required prior exposure of the flankers, and was strongly influenced by the semantic congruity of flankers and targets. These differing time courses suggest that perceptual priming encompasses a variety of distinct underlying cognitive and motor events.     

Priming effects in attentional gating

Three experiments were conducted to determine the effects of amount of prior target information (Experiment 1) and semantic priming (Experiment 2) in an attentional gating task. The goal was to determine some causes of the processing deficits commonly observed in perceiving successive visual stimuli. Items in a rapid serial visual presentation (RSVP) stream are subject to processing deficits before they are processed to the level of recognition (early selection) and after they have been recognized (late selection). Deficits in the former case presumably are due to an early filter that prevents complete recognition and semantic analysis, whereas deficits in the latter case arise from interference or response competition, producing forgetting among a set of recognized items. The semantic-priming effects found between a cue and a target (Experiment 2) and between two successive targets (Experiment 3) indicate that top-down processes can increase the subjective availability of related items. The results are consistent with the idea that most processing deficits observed in search through an RSVP sequence are due to limited capacity in our ability to form episodic representations of all the items in the sequence.     

The persistence of content-specific memory operations: Priming effects following a 24-h delay

The duration of long-term semantic priming is typically described in minutes. Woltz and Was (2007) found that priming effects following processing in working memory were relatively long-lasting, reporting there was no decrease in priming effects following 32 intervening Stroop-like trials. These findings were interpreted as an increased availability of long-term memory elements, in part due to memory for prior operations, and as not being solely explicable by spreading-of-activation accounts of priming. The present study was designed to test the persistence of these effects following a 24-h delay. In the present study, priming effects were found to be present following a minimum of a 24-h delay between processing of information in working memory and measures of increased availability of long-term memory elements. The results are discussed, in the context of long-term semantic priming, as being the result of persistent memory for prior cognitive operations.     

A diffusion model analysis of task interference effects in prospective memory

Holding an intention often interferes with other ongoing activities, indicating that resource-demanding processes are involved in maintaining the intention and noticing the appropriate event to fulfill it. Little is known, however, about the nature of the processes underlying this task interference effect. The goal of the present research was to decompose the processes contributing to the task interference effect by applying the diffusion model (Ratcliff, Psychological Review 85:59–108, 1978) to an event-based prospective memory task. In the first experiment, we validated the interpretation of the response criterion parameter (a) of the diffusion model as reflecting strategies to cope with the anticipated demands of a prospective memory task in the context of the ongoing task. The second experiment served to investigate which underlying processes contribute to the task interference often found with prospective memory tasks. Diffusion model analyses revealed that the task interference effect was due to (1) less efficient processing in the more demanding than in the less demanding prospective memory task and (2) a more conservative response criterion. We suggest that the anticipated demands and the additional processing demands of the prospective memory task jointly contribute to the task interference effect.     

Age effects in emotional prospective memory: cue valence differentially affects the prospective and retrospective component

While first studies suggested that emotional task material may enhance prospective memory performance in young and older adults, the extent and mechanisms of this effect are under debate. The authors explored possible differential effects of cue valence on the prospective and retrospective component of prospective memory in young and older adults. Forty-five young and 41 older adults performed a prospective memory task in which emotional valence of the prospective memory cue was manipulated (positive, negative, neutral). The multinomial model of event-based prospective memory was used to analyze effects of valence and age on the two prospective memory components separately. Results revealed an interaction indicating that age differences were smaller in both emotional valence conditions. For older adults positive cues improved the prospective component, while negative cues improved the retrospective component. No main effect of valence was found for younger adults on an overt accuracy measure, but model-based analyses showed that the retrospective component was enhanced in the positive compared with the negative cue condition. The study extends the literature in demonstrating that processes underlying emotional effects on prospective memory may differ depending on valence and age.     

The effects of task instructor status on prospective memory performance in preschoolers

The present study applied a 2 × 2 experimental design to assess prospective memory (PM) development across preschool age and to examine the effect of task instructor status (researcher vs. significant other) on PM performance in 80 preschool children. Participants were required to name pictures (ongoing task [OT]), and to remember to refrain from naming but instead give a different response to certain target cues (PM task). Although the OT was of comparable difficulty for both age groups (as indicated by no performance differences), results still indicated significantly higher PM performance in 5-year-olds than in 3-year-olds, confirming the age-related increase of PM capacities between 3 and 5 years. Furthermore, results showed a performance-enhancing effect of significant others as task instructors on both age-groups. Post-hoc analysis revealed that 3-year-olds instructed by a significant other still performed marginally worse than 5-year-olds instructed by a researcher, underlining the finding that substantial changes of PM capacities take place during early childhood.     

The effects of ongoing task absorption on event-based prospective memory in preschoolers

The current study applied a 2 × 2 experimental design to investigate the effects of ongoing task absorption on event-based prospective memory performance of children aged 3 and 5 years. Children were required to label pictures as ongoing task but to remember to refrain from picture naming and to respond to the target cues in a different way as the prospective memory task. Two differently absorbing ongoing tasks (high absorbing scenario game task vs. low absorbing computer-based task) were administered. Results indicated that prospective memory performance of 5-year-old children was significantly better than that of 3-year-old children. Ongoing task absorption affected the ongoing task performance of preschoolers, but not overall prospective memory performance. Only the 3-year-olds were negatively affected by high ongoing task absorption, which was not the case for the 5-year-olds. The findings are discussed within the light of the multiprocess theory.     

The effects of working memory resource availability on prospective memory: a formal modeling approach

The PAM theory of event-based prospective memory (Smith, 2003; Smith & Bayen, 2004a) proposes that successful prospective memory performance demands upon the interaction of preparatory attentional processes and retrospective memory processes. The two experiments in the current study represent the first application of a formal model to investigate the sensitivity of these underlying processes to variations in working memory resource availability. Multinomial modeling of data from prospective-memory tasks showed that working memory span influenced preparatory attentional processes and retrospective-memory processes.     

Priming effects with ambiguous figures

We varied the format and semantic content of primes to determine the degree to which they would influence the interpretation of ambiguous figures. The primes were objects or object names that were related in some way to one of the two organizations of the ambiguous figures. In Experiment 1, we provided some normative data regarding the stimulus materials, whereas in Experiment 2, an orienting question was used to focus attention on the semantic relationship between the prime and the figure. In Experiment 3, we used the orienting question to divert attention away from the relationship by asking about physical features of the figures. Recognition responses to biased versions of the figures and to new figures were measured. Primes that were loosely and indirectly associated with one of the two interpretations of an ambiguous figure were found to be effective at biasing the interpretation of an ambiguous figure in the direction of the primed alternative but only if attention was focused on the semantic relationship between the two stimuli. Attention to the physical characteristics of the stimuli during encoding eliminated the prime's influence on complex object perception. These findings are consistent with the conceptual priming literature and extend those of some recent studies (Balcetis & Dale, 2007; Feist & Gentner, 2007), which show that the interpretation of complex figures can be biased by the advanced presentation of related verbal information.     

The effects of enactment and intention accessibility on prospective memory performance

The intention-superiority effect denotes faster response latencies to stimuli linked with a prospective memory task compared to stimuli linked with no prospective task or with a cancelled task. It is generally assumed that the increased accessibility of intention-related materials contributes to successful execution of prospective memory tasks at an appropriate opportunity. In two experiments we investigated the relationship between the intention-superiority effect and actual prospective memory performance under relatively realistic conditions. We also manipulated enactment versus observation encoding to further investigate the similarity in representations of enacted and to-be-enacted tasks. Additionally, Experiment 1 included a control condition to investigate the development of the intention-superiority effect over time. Participants were asked to perform prospective tasks at the end of the experiment to prepare the room for the next participant. They studied these preparatory tasks at the beginning of the experiment either by enacting them themselves or by observing the experimenter perform them. In Experiment 2, participants in a control condition did not intend to perform prospective tasks. We observed a smaller intention-superiority effect after enactment encoding than after observation encoding, but only if response latencies were assessed immediately before the prospective memory task. In addition, Experiment 2 suggested that the size of the intention-superiority effect is related to successful prospective memory performance, thus providing evidence for a functional relationship between accessibility and memory.     

The effects of cognitive load and encoding modality on prospective memory

Cognitive Processing - Successful execution of an intention as planned is necessary for people's normal life. However, people sometimes even forget intentions that they consider as...     

Mood and prospective memory

This study considered the relationship between mood states, prospective memory, and retrospective memory among a non-clinical sample of undergraduate students. Multiple regression analyses with simultaneous entry of variables were undertaken to examine the unique contributions of the alternate memory test and the emotional states to memory test performance. As expected, retrospective free recall performance and anxiety made unique and significant contributions to performance on the prospective memory task. However, only prospective memory performance emerged as a significant predictor of retrospective free recall. It is suggested that none of the mood measures emerged as a significant predictor of retrospective memory performance because they do not account for unique variance. In contrast, the relationship between anxiety and prospective memory appears to be due to factors uniquely associated with anxiety, and unrelated to depression.