Directed forgetting of autobiographical events

Two diary experiments demonstrated directed forgetting (DF) of autobiographical events, previously observed only for less complex memory items. Using a 2-week diary paradigm, we compared recall between a group of participants who were directed to forget Week 1 memories (forget group) and a group who did not receive a forget instruction (remember group). In Experiment 1, the forget group remembered fewer items from Week 1 than did the remember group. The effect was observed for negative and positive valence events, as well as for high and low emotional intensity events. The effect was replicated in Experiment 2 despite a memorable holiday (Valentine's Day) that occurred during the manipulation week. Forget participants remembered fewer low emotional intensity items in Experiment 2. We conclude that intentional forgetting is a plausible explanation for the loss of some autobiographical memories.     

Ordering the components of autobiographical events

Memory for the temporal order of the components of autobiographical events was examined in two experiments. Experiments 1 and 2 examined the relationship between reaction times to recognise photographs of the components of events and ordering of these photographs. Reaction times were not related to true event position, nor to assigned temporal position, in a manner consistent with an activation strength model of temporal ordering. In contrast, ordering performance was found to be related to event vividness ratings, ability to classify a photograph as one the participant had taken, and retention interval. These findings are all consistent with the hypothesis that the order of an autobiographical event's components is determined by the associative structure that links each component to its general event memory. Overall, memory for the order of the components of autobiographical events may be initially based on associations between the event components and their general event memory representation. These associations appear to decay rapidly leaving only reconstructive ability as the determinant of event component order.     

How to accurately detect autobiographical events

ABSTRACT— We describe a new method, based on indirect measures of implicit autobiographical memory, that allows evaluation of which of two contrasting autobiographical events (e.g., crimes) is true for a given individual. Participants were requested to classify sentences describing possible autobiographical events by pressing one of two response keys. Responses were faster when sentences related to truly autobiographical events shared the same response key with other sentences reporting true events and slower when sentences related to truly autobiographical events shared the same response key with sentences reporting false events. This method has possible application in forensic settings and as a lie-detection technique.     

Recall of odors: naming and autobiographical memories illustrate odor aftereffects

In the study phase, subjects had to encode either odors or the names there of by generating autobiographical memories, by judging the quality of the food source of the odors, or by labeling responses to odors. At the testing stage, explicit and implicit olfactory memory performance was assessed. With recognition testing, the provision of odors at study improved performance. Furthermore, recognition depended on elaborative encoding conditions with olfactory stimuli only. Implicit memory was measured by the correctness and speed of labeling responses at the testing stage. Old odors were named more correctly and faster than new ones, but only if subjects had encoded odors in the study phase. These results demonstrate that implicit memory in naming odors depends on olfactory stimulus processing and is not a purely verbal priming effect. As a further measure of implicit memory, the speed of autobiographical memory productions was assessed. We registered shorter reaction times for old versus new odors. But again, this effect of implicit memory was restricted to conditions of odor pre-experiences in the study phase. We conclude that olfactory memory is based on different types of memory traces. Implicit memory measures may prove to be useful in isolating sensory and other attributes of olfaction that seem to be interacting in making explicit memory judgments.     

Time scale similarity and long-term memory for autobiographical events

We examine the extent to which retrieval from very long-term autobiographical memory is similar when participants are asked to retrieve from widely differing periods of time. Three groups of 20 participants were given 4 min to recall autobiographical events from the last 5 weeks, 5 months, or 5 years. Following recall, the participants dated their events. Similar retrieval rates, relative recency effects, and relative lag-recency effects were found, despite the fact that the considered time scales varied by a factor of 52. These data are broadly consistent with the principle of recency, the principle of contiguity (Howard & Kahana, 2002), and scale similarity in the rates of recall (Brown, Neath, & Chater, 2007; Maylor, Chater, & Brown, 2001). These findings are taken as support for models of memory that predict time scale similarity in retrieval, such as SIMPLE (Brown et al., 2007) and TCM (Howard & Kahana, 2002).     

Neuroticism and autobiographical memory for positive and negative events

Highly neurotic individuals tend to ruminate about negative aspects of their lives. Using an autobiographical memory task, the relation between neuroticism and recall latency of specific events was studied. It was predicted that the inverse relation between neuroticism and recall latency would be (a) strongest when subjects were given negative affect prompts and a negative prime; and (b) weakest when subjects were given positive affect prompts and a positive prime. Eighty college students completed a neuroticism scale and were randomly assigned to one of four cells formed by crossing Affect Prompt (positive vs negative) with Affect Prime (positive vs negative). Response times were analyzed using analysis of covariance (ANCOVA). Contrary to the hypothesis, no significant effects were observed. Based upon a two component model of autobiographical memory, it was suggested that highly neurotic individuals may be fast at searching for negative experiences, but because they are under chronic psychological distress, they find it difficult to link specific negative emotions with particular classes of daily events.     

Ageing and autobiographical memory for emotional and neutral events

We investigated age-related effects in recall of emotional and neutral autobiographical memories. Protocols were scored according to episodic and non-episodic detail categories using the Autobiographical Interview. Young adults recalled a greater number of episodic details compared to older adults, whereas older adults recalled more semantic details, replicating previous findings. Both young and older adults' emotional memories contained more overall detail than neutral ones, with the enhancement from emotion-specific to episodic details, but this did not alter the effect of age group on the pattern of episodic and semantic details. However, the age effect on episodic details was attenuated for neutral autobiographical memories. The findings suggest that age differences for emotional autobiographical recollection might reflect a more general pattern of age-related changes in memory, with impaired recall of episodic components and relative sparing of semantic aspects of autobiographical memory in older adults when compared to young adults.     

A test of the peak-end rule with extended autobiographical events

Forty-nine students went on vacation for an average of 7 days and sent daily text messages about the happiness they had experienced over the previous 24 h. After their vacation, they were questioned on the overall happiness they had experienced and were asked to recall the daily record of their happiness. The duration of the vacation had no effect on the subsequent evaluations, and participants were not able to recall the detail of their day-to-day changes in happiness. A number of summary measures provided reasonable prediction of the recalled overall happiness of the vacation. The peak-end rule was not an outstandingly good predictor. Overall, the results indicate much reconstruction of the affective states.     

Themes,events, and episodes in autobiographical memory

The process by which experience is divided into events was examined. Experiment 1 involved diarists recording their experiences over a 3-month period. Diary entries were later transcribed onto cards and the diarists arranged their cards so as to define events they had experienced, and in a separate phase arranged their cards so as to describe the themes that reflected their life. Examination of event- and theme-building strategies indicated that boundaries were frequently used, and events and themes were often formed from clusters of experience combined using content association rather than temporal sequence. Experiment 2 involved photographs taken by the participants, employed the same procedures as in Experiment 1, and revealed event- and theme-building strategies similar to those identified in Experiment 1. In Experiment 3 the size of the stimulus set from which events and themes were constructed was manipulated; this did not influence construction strategies. Overall, the experiments show that both autobiographical events and themes frequently consist of episodes taken from more than 1 day.     

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.     

Placing events in time: the role of autobiographical recollection

Episodic experience is argued to be rich in temporal information, but it remains unclear whether temporal information is directly coded in the event memory or is reconstructed at retrieval. The two experiments reported here emphasise the role of reconstructive processes of autobiographical context in establishing the date of memories. Younger and older participants were presented with famous public events, although only the latter had actually lived through them. Participants were asked to make forced-choice judgements about the date of the event and other event-related facts. Overall, while the older group showed better fact knowledge of the events, this did not translate into better dating performance. This older group showed similar dating performance across events with high and low factual knowledge. In contrast, the younger group's dating accuracy was determined by their level of knowledge. This suggests that older individuals who have direct episodic experience of an event may perform the task in a qualitatively different manner, eschewing semantic facts in favour of other sources of information. Crucially, this process does not appear to enhance performance. A second experiment addressed the issue of whether older participants date events based on general qualities of the event memory (e.g., vividness), the availability of other event-related semantic facts, or autobiographical context. It was found that the ability to place an event in autobiographical context is related to dating accuracy, but not to other aspects of memory.     

Placing events in time: The role of autobiographical recollection

Episodic experience is argued to be rich in temporal information, but it remains unclear whether temporal information is directly coded in the event memory or is reconstructed at retrieval. The two experiments reported here emphasise the role of reconstructive processes of autobiographical context in establishing the date of memories. Younger and older participants were presented with famous public events, although only the latter had actually lived through them. Participants were asked to make forced-choice judgements about the date of the event and other event-related facts. Overall, while the older group showed better fact knowledge of the events, this did not translate into better dating performance. This older group showed similar dating performance across events with high and low factual knowledge. In contrast, the younger group's dating accuracy was determined by their level of knowledge. This suggests that older individuals who have direct episodic experience of an event may perform the task in a qualitatively different manner, eschewing semantic facts in favour of other sources of information. Crucially, this process does not appear to enhance performance. A second experiment addressed the issue of whether older participants date events based on general qualities of the event memory (e.g., vividness), the availability of other event-related semantic facts, or autobiographical context. It was found that the ability to place an event in autobiographical context is related to dating accuracy, but not to other aspects of memory.     

Overgeneral autobiographical memory and traumatic events: an evaluative review

Does trauma exposure impair retrieval of autobiographical memories? Many theorists have suggested that the reduced ability to access specific memories of life events, termed overgenerality, is a protective mechanism helping attenuate painful emotions associated with trauma. The authors addressed this question by reviewing 24 studies that assessed trauma exposure and overgenerality, examining samples with posttraumatic stress disorder, acute stress disorder, depression, traumatic event exposure, and other clinical disorders. Limitations are discussed, including variations in assessment of events, depression, and overgenerality and the need for additional comparison groups. Across studies, there was no consistent association between trauma exposure and overgenerality, suggesting that trauma exposure is unlikely to be the primary mechanism leading to overgenerality. Instead, psychopathology factors such as depression and posttraumatic stress appear to be more consistently associated with overgenerality. Alternative overgenerality theories may help identify key overgenerality mechanisms, improving current understanding of autobiographical memory processes underlying psychopathology.     

Memory conjunction errors for autobiographical events: more than just familiarity

Two diary studies investigated the prevalence of memory conjunction errors for real-life events. In both studies, participants completed detailed diary pages over the course of several weeks. Participants in both diary studies committed memory conjunction errors on a later recognition memory test. In the second diary study participants also made remember/know judgements. For a large proportion of their memory conjunction errors participants indicated that they "remembered" the event occurring in that context. These diary studies demonstrate that memory conjunction errors do occur for autobiographical memories, and these errors can seem compelling.     

Memory conjunction errors for autobiographical events: More than just familiarity

Two diary studies investigated the prevalence of memory conjunction errors for real‐life events. In both studies, participants completed detailed diary pages over the course of several weeks. Participants in both diary studies committed memory conjunction errors on a later recognition memory test. In the second diary study participants also made remember/know judgements. For a large proportion of their memory conjunction errors participants indicated that they “remembered” the event occurring in that context. These diary studies demonstrate that memory conjunction errors do occur for autobiographical memories, and these errors can seem compelling.     

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.     

Phenomenal characteristics of autobiographical memories for positive,negative, and neutral events

We investigated memory qualities for positive, negative, and neutral autobiographical events. Participants recalled two personal experiences of each type and then rated their memories on several characteristics (e.g. sensorial and contextual details). They also reported whether they ‘see’ the events in their memories from their own perspective (‘field’ memories) or whether they ‘see’ the self engaged in the event as an observer would (‘observer’ memories). Positive memories contained more sensorial (visual, smell, taste) and contextual (location, time) details than both negative and neutral events, whereas negative and neutral memories did not differ on most dimensions. Positive and negative events were more often recollected with a field perspective than neutral events. Finally, participants were classified in four groups according to the repressive coping style framework. Emotional memories of repressors were not less detailed than those of the other groups. Copyright © 2002 John Wiley & Sons, Ltd.     

Phenomenal characteristics of autobiographical memories for social and non-social events in social phobia

Previous studies failed to show clear differences between people with social phobia and non-anxious individuals regarding the specificity and affective intensity of their autobiographical memories for social events. However, these studies did not assess the subjective experience associated with remembering. In this study, people with social phobia and non-anxious control participants recalled social and non-social events, and rated the phenomenal characteristics of their memories. The memories of people with social phobia for social events contained fewer sensorial details but more self-referential information than controls' memories. In addition, people with social phobia remembered social situations from an observer perspective, viewing themselves as if from outside, to a greater extent than controls. By contrast, the two groups did not differ concerning their memories for non-social events. These findings are discussed in relation to cognitive models of social phobia.     

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.