The role of lifetime periods in the organisation of episodic memories

ABSTRACT

Research on the nature of episodic memory associations has suggested that episodic memories are associated by conceptual knowledge, where memories cluster around the same content (e.g. memories about the same people) or general-event knowledge, where memories cluster around extended events (e.g. a holiday in London), repeated events (e.g. Sunday walks in the park), or causally related events (i.e. where one event leads to another). Research has also suggested that episodic memories are associated by lifetime periods (e.g. when I was in high school), where memories cluster within lifetime periods. However, it is unclear whether episodic memories can be associated solely by lifetime periods, or if such associations are subordinate to conceptual or general-event associations. To answer this question, we reanalysed a large sample of involuntary memory chains (Mace, J. H., Clevinger, A. M., & Bernas, R. S. (2013). Involuntary memory chains: What do they tell us about autobiographical memory organisation? Memory, 21, 324–335). The results of this analysis suggested that lifetime periods associations are subordinate to conceptual and general-event associations, as lifetime periods were found to cluster within the latter two associations. The potential functions of this organisation are discussed.     

Mental time travel into the episodic future,episodic past,and episodic counterfactual past in everyday life

To date, studies exploring the relationship of counterfactual thoughts with episodic memories and episodic future thoughts have focused mainly on voluntary mental time travel. We explore mental time travel in everyday life and find that episodic counterfactual thinking occurs to a much lesser extent than thinking about the past or the future (12%, 22%, and 54%, respectively), is used mainly for mood regulation purposes, and the temporal distribution decreases as a function of time. We observe similarities in phenomenological detail: memories and counterfactual thoughts sharing similar ratings of sensory detail, memories and future thoughts sharing similar ratings of positivity, and counterfactual and future thoughts sharing similar ratings of mental time travel. We discuss the implications of episodic counterfactual thinking in everyday life.     

心理时间旅行与自我:发展中关系模式的转换

该研究分别考察了儿童中晚期(9~12岁)、少年期(13~15岁)和青年早期(17岁、19岁、21岁)个体心理时间旅行的发展模式,并进一步探讨了不同年龄阶段,情景记忆和自我对情景预见作用模式的转换。研究采用访谈法评估心理时间旅行,以自我描述(儿童期和少年期)或自我连续性(青年早期)作为评估自我的指标。研究发现:(1)儿童中晚期,想象未来情景细节的数量随年龄增长而增加,少年期和青年早期的情景预见能力则趋于平稳,与情景记忆的发展趋势一致;(2)无论在哪个年龄段,情景记忆对情景预见都是有效的预测源;(3)自我描述在少年期才开始对情景预见产生预测作用;(4)青年早期,情景记忆以自我连续性为中介变量作用于情景预见。     

Changes in Children's Episodic Narratives Through Long-Term Repeated Recall: Longitudinal Case Studies1

This study aimed to investigate whether a child's narrative of a particular past episode would change in repeated reporting over the long term, and if so, how it would change. To answer these questions, I conducted longitudinal case studies of episodic reports by children every 2–6 months, from their early childhood to the age of 10–15 years. Criteria for inclusion were set in advance; seven episodic narratives meeting these criteria were analyzed. Two types of changes in the narratives were observed, as expected: that of including other information, and that of an event suddenly being reported after no recall for several years. Information from the children's surroundings seemed to be substantially involved in these changes in their episodic narratives. The present results also indicate that mothers' episodic memories are not always reliable and that the schema children have can influence their episodic memories.     

儿童心理时间之旅的发展

人类在心理上把自我投射到过去以重新经历过去事件以及把自我投射到未来以预先经历未来事件的能力被称为心理时间之旅。心理时间之旅是认知心理学、认知神经科学、进化心理学、比较心理学、发展心理学等多个学科共同关注的研究领域。目前有关个体心理时间之旅的发展研究表明,心理时间之旅大约出现在儿童3~5岁时。未来有关个体心理时间之旅的发展性研究应从研究范式、研究技术、认知机制、文化差异等方面加以改进。     

Psychobiological evidence for the distinction between episodic and semantic memory

The evidence for discrete neurobiological mechanisms that underlie episodic and semantic memory is reviewed. Published data from three separate lines of research are considered: studies of human amnesic patients, psychopharmacological studies of normal human subjects, and studies of working and reference memory in rodents, a distinction that is arguably analogous to the episodic/semantic dichotomy. It is concluded that the available evidence does not indicate that episodic and semantic memory are mediated by discrete neural subsystems. An alternative model of human memory is discussed, based on the concept of parallel distributed processing.An earlier version of this paper was submitted as part of the author's qualifying examination at Emory University.     

A critical evaluation of cognitive inhibition in dissociative identity disorder as inferred by negative priming in the flanker task: Limitations and the episodic retrieval alternative

Studies examining negative priming in dissociative identity disorder (DID) using the flanker task have reported emotional context effects. Significant negative priming is evident when individuals with DID are assessed in a context deemed emotionally neutral, while in contexts designed to elevate anxiety, DID samples display reduced negative priming. Limitations and considerations are discussed around statistical power, generalizability and reliability, and the use of diagnostic groups over specific clinical symptoms. The negative priming findings in this growing body of work have been interpreted with reference to the functioning of cognitive inhibitory mechanisms. Explored is how the episodic retrieval account of negative priming, with its reliance on memory mechanisms, could account for the DID findings. Encoding and retrieval possibilities are discussed and it is concluded that a failure to encode the prime trial distractor stimulus, in contexts of heightened anxiety, could explain the experimental findings from an episodic retrieval perspective.     

预期想象对拖延的影响:想象过程和想象结果的效应分离

摘要 为了考察预期想象对不同拖延水平个体拖延行为的影响,本研究采用一般拖延量表(General Procrastination Scale)选取高拖延被试和低拖延被试,要求被试在进行模拟现实的拖延任务之前分别对任务过程和任务结果进行预期想象,比较不同拖延水平的被试在预期想象作用下拖延行为的变化。结果表明：(1)在两组被试中,相比于无想象条件下的拖延行为,对任务过程的预期想象增强拖延行为,对任务结果的预期想象削弱拖延行为;(2)对任务不同成分的预期想象所引发的情绪与拖延行为的变化相关显著。这说明情绪和预期想象是影响拖延的重要因素,合理地操纵对任务不同成分的预期想象可以有效干预拖延行为。     

Remembering the past and imagining the future: Examining the consequences of mental time travel on memory

Cognitive, neuropsychological, and neuroimaging evidence suggests that remembering the past and imagining the future rely on overlapping processes in episodic memory. The three experiments reported here examine the consequences of remembering the past and imagining the future on the accessibility of other information in memory. Participants first studied events associated with a specific context and then either (a) retrieved past autobiographical events associated with that same context or (b) imagined future autobiographical events associated with that same context. Replicating and extending evidence of retrieval-induced forgetting, remembering autobiographical events from the past caused participants to forget the related studied events. However, imagining future autobiographical events failed to cause participants to forget the related studied events. These results suggest an important difference in the memorial consequences of remembering and imagining.     

More to it than meets the eye: how eye movements can elucidate the development of episodic memory

The ability to recognise past events along with the contexts in which they occurred is a hallmark of episodic memory, a critical capacity. Eye movements have been shown to track veridical memory for the associations between events and their contexts (relational binding). Such eye-movement effects emerge several seconds before, or in the absence of, explicit response, and are linked to the integrity and function of the hippocampus. Drawing from research from infancy through late childhood, and by comparing to investigations from typical adults, patient populations, and animal models, it seems increasingly clear that eye movements reflect item–item, item–temporal, and item–spatial associations in developmental populations. We analyse this line of work, identify missing pieces in the literature and outline future avenues of research, in order to help elucidate the development of episodic memory.     

Superior episodic memory in inconsistent-handers: a replication and extension using fNIRS

A large body of evidence supports the existence of a robust handedness difference in episodic memory retrieval, with inconsistent-handedness being associated with superior memory across a wide variety of paradigms, including superior retrieval of lab-based and real world memories. Despite superior episidoc memory in inconsistent-handers, and despite neuroanatomical and neurophysiological differences in cortical regions between inconsistent- and consistent-handers, we are aware of no studies to date that have examined physiological activity in the brains of inconsistent- versus consistent-handers while engaged in memory tasks. The purpose of this paper, therefore, is to present a first look at this issue, using functional near-infrared spectroscopy (fNIRS) as a simple, non-invasive measure of frontal lobe activity during encoding and recall of list words in inconsistent- and consistent-handers. Behaviourally, we replicated prior studies, finding a significant inconsistent-handed advantage in free recall. Using fNIRS-derived oxygenated haemoglobin (O₂Hb) as a measure of frontal lobe activity, we found the first evidence for handedness differences in brain activity that are associated with the handedness differences in episodic retrieval. Specifically, the primary finding was that increased O₂Hb in the right hemisphere during recall was associated with better retrieval, but for consistent-handers only.     

工作记忆模型的第四个组成部分——情景缓冲器

工作记忆的提出迄今已有30多年的历史了,随着实验方法和技术的发展对工作记忆的研究取得了很大的突破,但在很多问题上仍存在争议,特别是在工作记忆与长时记忆、语音回路与视空间模板的联结上的解释还有许多不足.基于此,Baddeley于2000年提出了工作记忆模型的第四个组成部分--情景缓冲器(episodic buffer).情景缓冲器是一个容量有限的暂时贮存多种编码信息的装置,它受中央执行系统的控制,而中央执行系统能够通过意识觉察从存贮中提取信息,反映信息,在必要的时候能够修正信息.新的工作记忆模型更加完整,更加有解释力.     

Sex Differences in Episodic Memory

ABSTRACT— Research shows sex differences in episodic memory. These differences vary in magnitude as a function of the type of material to be remembered. Throughout the life span, verbal episodic-memory tasks yield differences favoring women. In contrast, episodic-memory tasks requiring visuospatial processing result in differences favoring men. There are also sex differences favoring women on episodic-memory tasks requiring both verbal and visuospatial processing and on face-recognition tasks. Thus, there may be a small, general episodic-memory advantage for women—an advantage that can increase by the advantage women have over men in verbal production and can be reversed by the male advantage in visuospatial tasks. In addition, environmental factors affect the magnitude of the sex differences in episodic memory.     

Characteristics of personally important episodic memories,counterfactual thoughts,and future projections across age and culture

We have limited knowledge as to whether the phenomenological differences between episodic memories, counterfactuals, and future projections show the same pattern across age groups and diverse samples. Here we compared the characteristics of these mental events, reported by younger and older participants in a Turkish (Study 1) and in an American sample (Study 2). In both studies, memories contained more sensory-perceptual-spatial details, were easier to bring to mind, and more specific. Future projections were the most positive, whereas counterfactuals were the least emotionally intense. In Study 1, older participants rated the events more positively and experienced them with more perceptual detail, whereas younger participants reported the future to be more voluntarily rehearsed, important, and central. These age differences did not replicate in Study 2. Overall, phenomenological differences between the events are robust and replicate across diverse samples. However, age differences are more sensitive to cultural or individual differences.     

Remembering the past and imagining the future: attachment effects on production of episodic details in close relationships

Attachment theories and studies have shown that Internal Working Models (IWMs) can impact autobiographical memory and future-oriented information processing relevant to close relationships. According to the constructive episodic simulation hypothesis (CESH), both remembering the past and imagining the future rely on episodic memory. We hypothesised that one way IWMs may bridge past experiences and future adaptations is via episodic memory. The present study investigated the association between attachment and episodic specificity in attachment-relevant and attachment-irrelevant memory and imagination among young and older adults. We measured the attachment style of 37 young adults and 40 older adults, and then asked them to remember or imagine attachment-relevant and attachment-irrelevant events. Participants’ narratives were coded for internal details (i.e., episodic) and external details (e.g., semantic, repetitions). The results showed that across age group, secure individuals generated more internal details and fewer external details in attachment-relevant tasks compared to attachment-irrelevant tasks; these differences were not observed in insecure individuals. These findings support the CESH and provide a new perspective to understand the function of IWMs.     

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.     

Neural correlates of autobiographical memory retrieval in children and adults

Autobiographical memory (AM) is a critically important form of memory for life events that undergoes substantial developmental changes from childhood to adulthood. Relatively little is known regarding the functional neural correlates of AM retrieval in children as assessed with fMRI, and how they may differ from adults. We investigated this question with 14 children ages 8–11 years and 14 adults ages 19–30 years, contrasting AM retrieval with semantic memory (SM) retrieval. During scanning, participants were cued by verbal prompts to retrieve previously selected recent AMs or to verify semantic properties of words. As predicted, both groups showed AM retrieval-related increased activation in regions implicated in prior studies, including bilateral hippocampus, and prefrontal, posterior cingulate, and parietal cortices. Adults showed greater activation in the hippocampal/parahippocampal region as well as prefrontal and parietal cortex, relative to children; age-related differences were most prominent in the first 8?sec versus the second 8?sec of AM retrieval and when AM retrieval was contrasted with semantic retrieval. This study is the first to characterise similarities and differences during AM retrieval in children and adults using fMRI.