Separating past and future autobiographical events in memory: Evidence for a reality monitoring asymmetry

After thinking about the past and imagining the future, how do people separate these real and imagined events in memory? We had subjects engage in past and future autobiographical elaboration, then later take memory tests that required them to recollect these earlier generated events. In Experiment 1, testing memory for previously generated past or future autobiographical events led to fewer source memory confusions than did an elaborative control task, suggesting that the distinctive features of autobiographical elaboration improved subsequent retrieval monitoring accuracy. In Experiment 2, we directly compared retrieval monitoring accuracy for previously generated past and future autobiographical events and found that subjects made fewer source confusions when searching memory for future events. This asymmetry suggests that the features characterizing future elaborations (e.g., cognitive operations) were used more effectively during reality monitoring than were the features characterizing past elaborations (e.g., perceptual details), and has implications for future-oriented theories of memory.     

Prospective memory and aging: forgetting intentions over short delays

Retrieved intentions often cannot be performed immediately and must be maintained until there is an opportunity to perform them. In 3 experiments, on seeing a target event, younger and older participants were to withhold an action until they encountered the appropriate phase of the experiment. When initial retrieval was made facile by the use of a salient retrieval cue, the age-related decrements were often dramatic, even over unfilled delay intervals as brief as 10 s (Experiments 1 and 2). When initial retrieval was difficult, older adults showed no forgetting over the retention interval (Experiment 3). Several theoretical perspectives were offered as explanations for the age differences observed with salient retrieval cues, including those that focus on age differences in metamemory, the degree to which plans are reformulated, and the ability to nonstrategically maintain current concerns in working memory.     

Changing history: doctored photographs affect memory for past public events

We investigated how doctored photographs of past public events affect memory for those events. Italian participants viewed either original images or misleading digitally doctored images depicting the 1989 Tiananmen Square protest in Beijing and a 2003 protest in Rome against the war in Iraq, and they subsequently answered questions about those events. Viewing the doctored images affected the way participants remembered the events. Those who viewed the doctored photograph of the Beijing event estimated that a larger number of people participated in it. Those who viewed the doctored photograph of the Rome event rated the event as more violent and more negative, recalled more physical confrontation, damage to property, and injuries to demonstrators, and were less inclined to participate in future protests. Both younger and older adult participants were affected by the manipulation. Results indicate that doctored photographs of past public events can influence memory, attitudes and behavioural intentions. Copyright © 2007 John Wiley & Sons, Ltd.     

Children's temporal judgments for autobiographical past and future events

We compared the performance of twenty 5-7-year-olds on two spatial-temporal judgment tasks. In a semantic task, children located temporal distances from today that were described using conventional, temporal terms on a spatial timeline. In an autobiographical task, children judged temporal distances on the same spatial timeline for events that they had experienced, or were going to experience, presented without explicit temporal references. Six-year-olds were equally accurate in judging temporal distances in the semantic and autobiographical tasks, but 7-year-olds were more accurate in the semantic task. Older children were more accurate than younger children in the semantic task, but no significant age differences were found for autobiographical events. Surprisingly, children were equally accurate in locating past and future events in time. Children at both ages were more accurate judging temporal distances up to one week away (both past and future) as compared to distances of two to four weeks across both tasks. Results suggest that knowledge of recurring time patterns and conventional time measurement systems is necessary, but not sufficient, for locating autobiographical events in time, and temporal distance plays an important role in children's temporal judgments.     

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.     

Revisiting the past and back to the future: memory systems and the linguistic representation of social events.

Five studies were conducted to investigate the relationship between how people communicate about social events and how representations of these events are stored in memory. It was hypothesized that more distant events in memory would be described with more abstract linguistic predicates, and recent events with more concrete language. The 1st study supported this hypothesis. The 2nd and 3rd experiments demonstrated that abstract predicates used as prompts elicit memories that are significantly more removed in time than concrete predicates. Two final experiments showed that these outcomes are not merely a function of the type of semantic cue but an interaction between memory and preferential predicate use. The findings illustrate a link between memory and communicative behavior of a type that has not been previously studied. The results are discussed in terms of a recent, well-supported model of 2 separate fast-learning and slow-learning memory systems.     

Children's memory for the times of events from the past years

This study tested 8–12‐year‐olds' ability to localize in time parent‐reported events from four time intervals ranging from 6 months to 4 years ago. Memory for content was very accurate, and children's time estimates showed substantial agreement with the times provided by their parents. Accuracy of year judgments declined with retention interval, with the greatest change occurring between the 1–2‐year and 2–3‐year intervals. Season, month and time of day accuracy were much more stable over time. There were significant improvements with age in performance on measures of conventional time knowledge, and this performance was correlated with the accuracy of time estimates on the long time scales, controlling for age and general cognitive ability. Copyright © 2010 John Wiley & Sons, Ltd.     

Reconstructing the times of past and future personal events

Humans have the remarkable ability to mentally travel through past and future times. However, while memory for the times of past events has been much investigated, little is known about how imagined future events are temporally located. Using a think-aloud protocol, we found that the temporal location of past and future events is rarely directly accessed, but instead mostly relies on reconstructive and inferential strategies. References to lifetime periods and factual knowledge (about the self, others, and the world) were most frequently used to determine the temporal location of both past and future events. Event details (e.g., places, persons, or weather conditions) were also used, but mainly for past events. Finally, the results showed that events whose temporal location was directly accessed were judged more important for personal goals. Together, these findings shed new light on the mechanisms involved in locating personal events in past and future times.     

Predicting future blood donor returns: past behavior, intentions, and observer effects.

A prospective design was used to explore the efficacy of 6 factors (e.g., intentions) to predict the number of future blood donations in an initial sample of 630 blood donors. Differential predictions are made for the roles of past behavior and intentions with respect to occasional (4 or fewer previous blood donations) and regular (5 or more previous blood donations) blood donors. Intentions were predictive for occasional donors, and past behavior was predictive for regular donors. Furthermore, for regular donors only, an inverted U-shaped curve explained the relationship between past behavior and future behavior. Finally, it is reported that observing others fainting produces a reduction in the number of future donations for occasional donors. The theoretical and practical implications of these findings are discussed.     

Monitoring the future: object and source memory for real and imagined events

In these experiments a memory‐monitoring decision is made, whereby subjects must decide not only whether or not to‐be‐learned stimuli will be remembered—the focus of all of the past research into the Judgement of Learning (JOL)—but also whether they will be able to assess the source of those stimuli, as assessed by a new measure, Judgement of Source (JOS). In Experiment 1 subjects had to judge whether they would remember the occurrence and the source of items that were either seen or imagined. Although seen items were better remembered and sourced than imagined, subjects were unable to predict this outcome: they underestimated their ability to recall seen items and overestimated their ability to recall imagined items. In Experiment 2 subjects had to discriminate between self‐performed or other‐performed enacted or imagined events. We expected that the motor cues associated with overt performance should provide more sensory information than had the visual input in Experiment 1, and this should help subjects to discriminate between real and imagined items. As predicted, JOL magnitude showed that subjects were now able to predict accurately that they would recall more enacted events than imagined events. JOS magnitude showed that subjects incorrectly predicted that self‐enactment would assist source memory compared to imagination. However, it was the source of other‐focused events which was more accurately remembered. The results are discussed in terms of Koriat's (1997) view about cue utility in making JOLs. Copyright © 1999 John Wiley & Sons, Ltd.     

A wrinkle in time: asymmetric valuation of past and future events

ABSTRACT— A series of studies shows that people value future events more than equivalent events in the equidistant past. Whether people imagined being compensated or compensating others, they required and offered more compensation for events that would take place in the future than for identical events that had taken place in the past. This temporal value asymmetry (TVA) was robust in between-persons comparisons and absent in within-persons comparisons, which suggests that participants considered the TVA irrational. Contemplating future events produced greater affect than did contemplating past events, and this difference mediated the TVA. We suggest that the TVA, the gain-loss asymmetry, and hyperbolic time discounting can be unified in a three-dimensional value function that describes how people value gains and losses of different magnitudes at different moments in time.     

The present projects past behavior into the future while the past projects attitudes into the future: How verb tense moderates predictors of drinking intentions

Three studies examined how the use of the present versus the past tense in recalling a past experience influences behavioral intentions. Experiment 1 revealed a stronger influence of past behaviors on drinking intentions when participants self-reported an episode of excessive drinking using the present tense. Correspondingly, there was a stronger influence of attitudes towards excessive drinking when participants self-reported the episode in the past tense. Experiments 2 and 3 liked this effect to changes in construal level (Liberman, Trope, & Stephan, 2007; Trope & Liberman, 2003), with the present tense being similar to a concrete construal level and the past tense being similar to an abstract construal level.     

Age-related positivity effects and autobiographical memory detail: evidence from a past/future source memory task

This study investigated whether the age-related positivity effect strengthens specific event details in autobiographical memory. Participants retrieved past events or imagined future events in response to neutral or emotional cue words. Older adults rated each kind of event more positively than younger adults, demonstrating an age-related positivity effect. We next administered a source memory test. Participants were given the same cue words and tried to retrieve the previously generated event and its source (past or future). Accuracy on this source test should depend on the recollection of specific details about the earlier generated events, providing a more objective measure of those details than subjective ratings. We found that source accuracy was greater for positive than negative future events in both age groups, suggesting that positive future events were more detailed. In contrast, valence did not affect source accuracy for past events in either age group, suggesting that positive and negative past events were equally detailed. Although ageing can bias people to focus on positive aspects of experience, this bias does not appear to strengthen the availability of details for positive relative to negative past events.     

Age-related positivity effects and autobiographical memory detail: Evidence from a past/future source memory task

This study investigated whether the age-related positivity effect strengthens specific event details in autobiographical memory. Participants retrieved past events or imagined future events in response to neutral or emotional cue words. Older adults rated each kind of event more positively than younger adults, demonstrating an age-related positivity effect. We next administered a source memory test. Participants were given the same cue words and tried to retrieve the previously generated event and its source (past or future). Accuracy on this source test should depend on the recollection of specific details about the earlier generated events, providing a more objective measure of those details than subjective ratings. We found that source accuracy was greater for positive than negative future events in both age groups, suggesting that positive future events were more detailed. In contrast, valence did not affect source accuracy for past events in either age group, suggesting that positive and negative past events were equally detailed. Although ageing can bias people to focus on positive aspects of experience, this bias does not appear to strengthen the availability of details for positive relative to negative past events.     

Children's reasoning about the temporal order of past and future events

Four- and five-year-olds completed two sets of tasks that involved reasoning about the temporal order in which events had occurred in the past or were to occur in the future. Four-year-olds succeeded on the tasks that involved reasoning about the order of past events but not those that involved reasoning about the order of future events, whereas 5-year-olds passed both types of tasks. Individual children who failed the past-event tasks were not particularly likely to fail the more difficult future-event tasks. However, children's performance on the reasoning tasks was predictive of their performance on a task assessing their comprehension of the terms “before” and “after.” Our results suggest that there may be a developmental change over this age range in the ability to flexibly represent and reason about the before-and-after relationships between events.     

Working memory involved in predicting future outcomes based on past experiences

Deficits in working memory have been shown to contribute to poor performance on the Iowa Gambling Task [IGT: Bechara, A., &; Martin, E.M. (2004). Impaired decision making related to working memory deficits in individuals with substance addictions. Neuropsychology, 18, 152–162]. Similarly, a secondary memory load task has been shown to impair task performance [Hinson, J., Jameson, T. &; Whitney, P. (2002). Somatic markers, working memory, and decision making. Cognitive, Affective, &; Behavioural Neuroscience, 2, 341–353]. In the present study, we investigate whether the latter findings were due to increased random responding [Franco-Watkins, A. M., Pashler, H., &; Rickard, T. C. (2006). Does working memory load lead to greater impulsivity? Commentary on Hinson, Jameson, and Whitney’s (2003). Journal of Experimental Psychology: Learning, Memory &; Cognition, 32, 443–447]. Participants were tested under Low Working Memory (LWM; n = 18) or High Working Memory (HWM; n = 17) conditions while performing the Reversed IGT in which punishment was immediate and reward delayed [Bechara, A., Dolan, S., &; Hindes, A. (2002). Decision making and addiction (part II): Myopia for the future or hypersensitivity to reward? Neuropsychologia, 40, 1690–1705]. In support of a role for working memory in emotional decision making, compared to the LWM condition, participants in the HWM condition made significantly greater number of disadvantageous selections than that predicted by chance. Performance by the HWM group could not be fully explained by random responding.     

The temporal distribution of past and future autobiographical events across the lifespan

Knowledge and awareness of past and future autobiographical events may be mediated by a common system that supports intentional, goal-directed behavior. The purpose of this study was to assess the correspondence of past and future autobiographical thought. In Experiment 1, 300 undergraduates aged 19 years generated and assigned dates to past and f utu re autobiographical events. Thetemporal distribution of past events replicated a power function for retention as has been described in past research. The intention function of future autobiographical events fit the inverse of this same power function, reflecting a temporality of past and future mental time travel centered around the present moment. In Experiment 2, these findings were extended to young, middle-aged, and older groups. These data provide empirical support for the notion that thinking outside of "now" is mediated by a common system, regardless of whether one is thinking about the past or the future.     

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.     

The comparative mind-set: from animal comparisons to increased purchase intentions

Stimulating people to state a preference for one of two commercial products can increase their willingness to purchase not only one of these products, but also other products in a totally unrelated domain. However, willingness to make a purchase in a given domain (e.g., computers) can also be increased by asking individuals (a) to indicate which of two stimuli in a different domain (e.g., vacation packages) they dislike more, (b) to compare the relative attractiveness of wild animals, (c) to compare the animals with respect to physical attributes, and (d) to estimate how similar one object is to another. Moreover, the effects generalize to decisions about dating partners, as well as consumer products. In short, making any type of comparative judgment appears likely to give rise to a comparative-judgment mind-set and, therefore, to influence decisions in subsequent situations.