The use of partial temporal information in dating personal events

Memory & Cognition - The use of different types of partial temporal information is shown to affect dating accuracy and the distribution of errors in event dating. Several different types of...     

Hypnosis versus relaxation: accuracy and confidence in dating international news events

This study compared participants who were administered either a hypnosis (n=50) or a relaxation (n=44) recall priming procedure in terms of the ability to estimate the dates of 20 relatively memorable (‘easy’) vs. less memorable (‘difficult’) international news events. The hypnosis and relaxation groups performed comparably in terms of the accuracy of estimates of when the events occurred, self‐reported confidence in estimates, and the memorability and emotionality of the events that were reported during hypnosis and relaxation. After these initial ratings, participants were informed that ‘at least one’ of their estimates was incorrect, and they were given the opportunity to change their estimates of the date of when one or more of the events occurred. Participants who generated their initial estimates during hypnosis were less likely to change their previous estimates of both easy and difficult events, than were participants in the relaxation condition. The measure of self‐reported confidence and a behavioural measure of willingness to change initial reports were largely dissociated from one another. Copyright © 2005 John Wiley & Sons, Ltd.     

Reminiscence bump in memory for public events

People tend to recall more personal events from adolescence and early adulthood than from other lifetime periods. Most evidence suggests that differential encoding causes this reminiscence bump. However, the question why personal events are encoded better in those periods is still unanswered. To shed more light on this discussion, we examined memory for public events. Since it is often impossible to ascertain that queried events are equally difficult, we circumvented the issue of equivalence by calculating deviation scores for each trial. We found that participants more frequently answered questions correctly about events that occurred in the period in which they were between 10 and 25 years old. Furthermore, we found that the reminiscence bump was more pronounced for cued recall than for recognition. We argue that these results support the biological account that events are stored better, because the memory system is working more efficiently during adolescence and early adulthood. These results do not falsify the other accounts for differential encoding, because they are not mutually exclusive.     

Characteristics of proper names and temporal memory of social news events

Long-term memory of social news events was investigated by means of a questionnaire methodology with a large sample of participants. In Experiment 1, a total of 501 university students were asked to give proper names (i.e., persons and places) that related to a certain news event, and to estimate the date of the event. The accuracy of proper names (especially person names) was superior to that of estimated date (i.e., year). In addition, telescoping effects were found in the events that occurred more than 3 years ago, but time expansion effects emerged in the events that occurred less than 2 years ago. In Experiment 2, in which 182 students participated, the accuracy of proper names and the date estimates tended to be high on the events that participants judged to be given frequent exposure by the mass media. Based on these results, we discuss long-term memory and temporal schemata regarding social news events.     

Characteristics of proper names and temporal memory of social news events

Long-term memory of social news events was investigated by means of a questionnaire methodology with a large sample of participants. In Experiment 1, a total of 501 university students were asked to give proper names (i.e., persons and places) that related to a certain news event, and to estimate the date of the event. The accuracy of proper names (especially person names) was superior to that of estimated date (i.e., year). In addition, telescoping effects were found in the events that occurred more than 3 years ago, but time expansion effects emerged in the events that occurred less than 2 years ago. In Experiment 2, in which 182 students participated, the accuracy of proper names and the date estimates tended to be high on the events that participants judged to be given frequent exposure by the mass media. Based on these results, we discuss long-term memory and temporal schemata regarding social news events.     

Assessing remote memory with an improved public events questionnaire

In the present research, public events recall and recognition tests were developed that appear to be psychometrically stronger than those used in the past. Following test construction, these tests were administered to older and middle-aged participants in order to examine the effects of chronological age and historical time period on memory for remote news events. Results indicated that middle-aged participants generally exhibited a better memory for news events than did older participants for the time periods that both age groups lived through. Across the life span, a common pattern was observed. Specifically, there was an increase in memory for events until the teenage years and fairly constant performance thereafter for both age groups. From these findings, we can clearly argue against a loss theory of remote memory. Some gender differences were observed on the recall and recognition tasks, but they were not as global or as frequent as Botwinick and Storandt (1980) suggested. The clinical potential of the remote memory tests is briefly considered.     

Remote memory: recalling autobiographical and public events from across the lifespan.

In this study the recall of autobiographical and public events across the lifespan was examined in a sample of middle-aged and older-aged adults. The tasks were modified versions of one first introduced by Galton (1879), and they required subjects to recall events from specific time periods across their entire lifespan. The four tasks differed in the nature of the episodes requested (autobiographical or public) and whether recall was word-cued or non-word-cued. Verification of public events was assessed archivally, and autobiographical events were verified by a sample of relatives for a subgroup of the subjects and reported events. The results indicated that memory for public events decreases with increased age of the subject, but this effect is not generally found for the recall of autobiographical events. The older-aged subjects were able to recall an equal number of autobiographical episodes from all life segments, whereas recall of news events tended to decrease with remoteness of the episode. These data are contrary to those models that posit general memory loss as a function of age or of remoteness of the events.     

Effect of personal involvement in traumatic events on memory: The case of the Dolphinarium explosion

The association between memories of the terrorist explosion at the Dolphinarium discotheque in Tel Aviv and the level of personal involvement in the explosion was investigated. Memories of injured victims, uninjured eyewitnesses, and uninvolved controls who learned about the explosion from the mass media were compared. It was expected that memory of the explosion would be most and least detailed and accurate among the victims and the controls, respectively. The participants responded to an open-ended question about the explosion, as well as to specific and multiple-choice questions. Data analyses showed that the victims and the eyewitnesses remembered more details than the controls, and that the victims remembered both central and peripheral details more accurately than the other participants. Degree of involvement in the same traumatic experience was thus shown to be differentially associated with memory accuracy.     

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.     

Telescoping in dating naturally occurring events

Telescoping effects in date estimation were examined in four diary studies. The data show that substantial telescoping can begin as soon as 8 weeks after an event occurs. These studies also found a slight, but typically nonreliable, tendency to make time expansion errors for recent events. Analyses of these data showed that telescoping cannot be attributed to the clarity-of-memory hypothesis proposed by Bradburn, Rips, and Shevell (1987) or to an artifact produced by guessing. An implicit strategy involving estimation of the number of intervening events was proposed to account for the results.     

Segmentation in the perception and memory of events

People make sense of continuous streams of observed behavior in part by segmenting them into events. Event segmentation seems to be an ongoing component of everyday perception. Events are segmented simultaneously at multiple timescales, and are grouped hierarchically. Activity in brain regions including the posterior temporal and parietal cortex and lateral frontal cortex increases transiently at event boundaries. The parsing of ongoing activity into events is related to the updating of working memory, to the contents of long-term memory, and to the learning of new procedures. Event segmentation might arise as a side effect of an adaptive mechanism that integrates information over the recent past to improve predictions about the near future.     

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.     

Photographs can distort memory for the news

In this experiment, we ask whether photographs can lead to false memories for elements of a newspaper story. Participants played the role of a newspaper editor, identifying minor typographical errors in three newspaper articles and marking the text where they thought an accompanying photo should be placed when the story was printed. The critical article described a hurricane's effects on a coastal region; the story made no mention of personal injury or death. We varied the accompanying critical photo: participants saw either a photo of a village before the hurricane hit or after. In a later memory test, both ‘Before’ and ‘After’ participants were equally good at correctly recognising old statements and rejecting weak lures. However, the ‘After’ participants claimed to have read information describing death and injury 32% of the time. By comparison, ‘Before’ participants claimed to have read these statements only 9% of the time. Copyright © 2007 John Wiley & Sons, Ltd.     

Interference and the representation of events in memory.

Most current models of memory predict that the presence of increasingly well-learned, or strong, items in memory will cause increasing interference. This phenomenon, the list-strength effect, occurs as predicted when memory is tested by free recall but not when a recognition test is used. Four experiments use end-of-session testing to demonstrate that redistribution of storage time or effort from strong to weak items on mixed lists does not occur and therefore cannot be masking interference by strong items. Delay between study and test is found to cause memory loss independent of the basic list-strength findings. It is concluded that the presence of strong items in memory does not interfere with recognition performance and that interference is due to failures of retrieval rather than to composition or other forms of destructive interaction during storage.     

Scaling of involvement in personal and global future events

Abstract.— Magnitude estimates of intensity of emotional involvement in 12 potential future events, assumed to occur at 5 alternative points of time within the next 46 years, were obtained from 75 subjects (mean age 19.1 yrs). Two types of relation between involvement and time were found, the dominant one being an exponential decrease of involvement with increasing temporal distance. The response patterns became less differentiated with increasing temporal distance. Differences in the response patterns between men and women, and between subjects differing in respect to satisfaction, activity, and optimism, are discussed.     

An exploration of the relationship among valence,fading affect,rehearsal frequency,and memory vividness for past personal events

The affect associated with negative (or unpleasant) memories typically tends to fade faster than the affect associated with positive (or pleasant) memories, a phenomenon called the fading affect bias (FAB). We conducted a study to explore the mechanisms related to the FAB. A retrospective recall procedure was used to obtain three self-report measures (memory vividness, rehearsal frequency, affective fading) for both positive events and negative events. Affect for positive events faded less than affect for negative events, and positive events were recalled more vividly than negative events. The perceived vividness of an event (memory vividness) and the extent to which an event has been rehearsed (rehearsal frequency) were explored as possible mediators of the relation between event valence and affect fading. Additional models conceived of affect fading and rehearsal frequency as contributors to a memory’s vividness. Results suggested that memory vividness was a plausible mediator of the relation between an event’s valence and affect fading. Rehearsal frequency was also a plausible mediator of this relation, but only via its effects on memory vividness. Additional modelling results suggested that affect fading and rehearsal frequency were both plausible mediators of the relation between an event’s valence and the event’s rated memory vividness.     

Reminiscence bump in autobiographical memory: Unexplained by novelty,emotionality, valence,or importance of personal events

People tend to recall a disproportionately large number of personal events from their adolescence and early adulthood. This “reminiscence bump” has been examined extensively, but its causes remain unclear. In this Internet-based experiment, nearly 3,500 participants were given 10 cue words and were asked to describe the personal events that came to mind. Furthermore, they were asked to date each event and to indicate whether it was a first-time experience. Finally, the participants were asked to rate the strength of the emotional reaction to the event or the valence or the importance of the event. Surprisingly, the reminiscence bump consisted of relatively fewer novel, emotional, important positive or negative events. This result increases the likelihood of an alternative explanation—namely, that memory is generally enhanced in adolescence and early adulthood. However, this account has not been tested directly.     

Scale effects in memory for the timeof events

This study addressed the question of how people remember the time of past events. Stimuli were 10 news events that had occurred from 6 months to 20 years before the study. In contrast to previous studies of memory for time, subjects were asked to provide estimates of the stimulus events on multiple time scales, including year, month, day of the month, day of the week, and hour. If judgments are based on direct information about the age of the memory, accuracy should decrease monotonically as one moves to finer scales. Alternatively, if subjects reconstruct the time from fragmentary information associated with the event, one would expect that estimates on finer time scales would often exceed grosser scales in accuracy. Results for accuracy, confidence, and number of recall cues supported the latter position. In addition, subjects reported a variety of types of recall cues, the most common being memory for personal experiences or events that were contiguous with the news event.