Memories Of Personal Events Research Articles

The influence of electroconvulsive therapy on reconsolidation of autobiographical memories: A retrospective quasi-experimental study in patients with depression

Background/ObjectiveElectroconvulsive therapy (ECT) is effective for treatment-resistant and psychotic depression. One previously reported side effect of ECT is the disruption of memory reconsolidation. This study examines whether this disruption induced by ECT can be detected in routine neuropsychological assessments. MethodsIn this retrospective study, the Autobiographical Memory Interview (AMI) was applied before and after ECT. Memories of the same events and facts were tested pre and post ECT treatments. 38 patients, receiving ECT for the treatment of unipolar or bipolar depression, were matched for age, sex, and stimulus intensity and divided into two groups: Group A was tested on the day before the first ECT treatment, whereas group B two or more days before. ResultsPatients who were tested by AMI on the day before ECT and thus reactivated memorie shortly before the first ECT treatment deteriorated in AMI score. Patients who had at least two days between memory activation and treatment improved regarding the number of recalled memories. Memory impairment was not associated with depression severity. ConclusionThis finding suggests that ECT might be capable of impairing reconsolidation. The study demonstrates that memories of personal events can potentially be affected by ECT within a time interval of 24 h of memory vulnerability after reactivation. Implications for practice and future research are discussed.

The Mood Repair Effect of Positive Involuntary Autobiographical Memory Among Japanese Adults: An Experimental Study

Involuntary autobiographical memories are memories of personal events that come to mind without an intentional attempt at retrieval. Previous studies have shown that positive involuntary autobiographical memory retrieval improves negative mood, known as the mood repair effect, in daily life. However, the cues relating to involuntary autobiographical memories were not controlled in these previous studies, and the mood repair effect has not been shown experimentally. Therefore, this study aimed to experimentally examine the mood repair effect of positive involuntary autobiographical memory among Japanese adults. After a pilot study to select cue words, we examined whether positive involuntary autobiographical memory retrieval could improve negative mood. As a result, mood improvement was enhanced by positive memory being recalled involuntarily, while mood improvement was shown with and without the retrieval of the positive involuntary autobiographical memory. Therefore, the mood repair effect by positive IAM was shown even after preventing the influence of the emotional valence of retrieval cues. From these results, the mood repair effect of positive involuntary autobiographical memory retrieval was experimentally demonstrated among Japanese adults.

How do we remember public events? Pioneering a new area of everyday memory research

Although most of us consume news reports about public events day by day, little is known about how memories of public events are remembered in everyday life. Across three studies, we examined voluntary (deliberately retrieved) and involuntary (spontaneously arising) public event memories by directly comparing them with voluntary and involuntary personal event memories. In particular, we examined the relative frequency of public event memories, correlations with individual differences measures, the emotional tone of remembered public events, phenomenological characteristics associated with remembering, and functions of public event memories. Against a background of replications of well-established findings from the autobiographical memory literature, several novel findings on public event memories emerged: Public event memories arose both deliberately and spontaneously in daily life, but they were less frequent and less positive than memories of personal events. Similar to personal memories, frequency estimates for involuntary public event memories correlated significantly with individual differences measures of daydreaming as well as depressive and PTSD symptoms. The phenomenological characteristics of public event memories showed large differences to personal event memories. For example, they were judged to be more emotionally negative, less specific, less vivid and to come with a lower sense of reliving. Moreover, public event memories seemed to predominantly serve a social function. The results suggest that deliberate and involuntary memory retrieval of public events in daily life may support the formation and maintenance of collective memories.

Autobiographical Memory Fluency Reductions in Cognitively Unimpaired Middle-Aged and Older Adults at Increased Risk for Alzheimer's Disease Dementia.

Recent research has revealed that cognitively unimpaired older adults who are at higher risk for developing Alzheimer's disease (AD) dementia often exhibit subtle cognitive alterations in their neuropsychological profiles. Emerging evidence suggests that autobiographical memory, which is memory for personal events and knowledge, may be sensitive to early AD-related cognitive alterations. In the present study, we investigated whether the rapid generation of autobiographical memory category exemplars, a retrieval process that taxes the neural network that is vulnerable to early AD, is compromised in cognitively unimpaired middle-aged and older carriers of the e4 allele of the apolipoprotein E gene (APOE4), which increases risk for AD dementia. In addition to standard neuropsychological tests, we administered a fluency task that requires generating exemplars for two types of autobiographical memory, namely episodic memories and personal semantics, to a group of cognitively unimpaired middle-aged and older adults (n = 45) enriched with APOE4 carriers (n = 20). While no APOE4 deficits were found on standard neuropsychological tests, episodic and personal semantic exemplar generation was reduced in the APOE4 group. Autobiographical memory aberrations associated with a higher risk for AD are evident in fluency and affect both episodic memory and personal semantics.

Involuntary autobiographical memories and their relation to other forms of spontaneous thoughts.

Involuntary autobiographical memories are memories of personal events that come to mind spontaneously-that is, with no conscious initiation of the retrieval process. Such spontaneously arising memories were long ignored in cognitive psychology, which generally has focused on controlled and strategic forms of remembering, studied in laboratory settings. Recent evidence shows that involuntary memories of past events are highly frequent in daily life, and that they represent a context-sensitive, and associative way of recollecting past events that involves little executive control. They operate by constraints that favour recent events and events with a distinct feature overlap to the current situation, which optimizes the probability of functional relevance to the ongoing situation. In addition to adults, they are documented in young children and great apes and may be an ontogenetic and evolutionary forerunner of strategic retrieval of past events. Findings suggest that intrusive involuntary memories observed clinically after traumatic events should be viewed as a dysfunctional subclass of otherwise functional involuntary autobiographical memories. Because of their highly constrained, situation-dependent and automatic nature, involuntary autobiographical memories form a distinct category of spontaneous thought that cannot be equated with mind wandering. This article is part of the theme issue 'Offline perception: voluntary and spontaneous perceptual experiences without matching external stimulation'.

Eye movements of recent and remote autobiographical memories: fewer and longer lasting fixations during the retrieval of childhood memories

There is an increased interest in the study of eye movements during the retrieval of autobiographical memories. Following this trend, the aim of the current study was to evaluate eye movements during the retrieval of remote and recent autobiographical memories. We instructed 71 participants to retrieve memories of personal events from early childhood (6-10years), late childhood/early adolescence (11-14years), late adolescence (15-18years), and the last month. During the retrieval of these memories, participants wore eye-tracking glasses. Analyses showed that early childhood memories triggered fewer fixations and fixations with longer durations than memories from the last month. However, no significant differences were observed for the number of saccades, saccade durations, or total amplitude of the saccades. The fewer and longer lasting fixations during the retrieval of early childhood memories can be attributed either to the visual system reconstructing remote memories from an observer perspective or to difficulties when reconstructing remote memories.

“I Remember the Fall”: Memory of Falls in Older Adults

ABSTRACT Objectives While there is a large body of research on falls and their consequences in older adults, little is known about how older adults remember them. We addressed this gap by inviting older adults to remember falls and control memories. Methods We analyzed specificity of memories and invited participants to rate emotional valence, mental time travel, visual imagery, importance, and rehearsal, as experienced during retrieval. Results Although analysis demonstrated no significant differences between memories of falls and control memories regarding specificity, participants rated memories of falls as more negative than control memories. Furthermore, they rated memories of falls as triggering higher mental time travel, higher visual imagery, higher importance, and higher rehearsal than control memories. Conclusions The negative emotional valence of memories of falls, as well as their ability to trigger significant levels of mental time travel, visual imagery, importance, and rehearsal, demonstrate how these memories are different from other memories in older adults. Clinical implications The findings demonstrate how falls can modulate memory of personal events in older adults.

A causal role for the precuneus in network-wide theta and gamma oscillatory activity during complex memory retrieval.

Complex memory of personal events is thought to depend on coordinated reinstatement of cortical representations by the medial temporal lobes (MTL). MTL-cortical theta and gamma coupling is believed to mediate such coordination, but which cortical structures are critical for retrieval and how they influence oscillatory coupling is unclear. We used magnetoencephalography (MEG) combined with continuous theta burst stimulation (cTBS) to (i) clarify the roles of theta and gamma oscillations in network-wide communication during naturalistic memory retrieval, and (ii) understand the causal relationship between cortical network nodes and oscillatory communication. Retrieval was associated with MTL-posterior neocortical theta phase coupling and theta-gamma phase-amplitude coupling relative to a rest period. Precuneus cTBS altered MTL-neocortical communication by modulating theta and gamma oscillatory coupling. These findings provide a mechanistic account for MTL-cortical communication and demonstrate that the precuneus is a critical cortical node of oscillatory activity, coordinating cross-regional interactions that drive remembering.

The Psychology of Memory and the Study of the Gospels

New Testament scholars who have some acquaintance with the cognitive psychology of memory have tended to conclude that memory is generally unreliable. Research in cognitive psychology does not support that view. These New Testament scholars have been misled especially by failure to distinguish different types of memory, by relying heavily on study of eyewitness testimony in court (a special category from which it is not legitimate to draw broader conclusions), and by misunderstanding the deliberate focus on the failures of memory in much of the research (which is not because failures are common but because failures are interesting). For research in this field to be useful in the study of the Gospels, we need to distinguish personal event memory from other types and to specify the conditions under which this type of memory tends to be either accurate or misleading.

Words-In-Sequence Memory Formed by Eye Movement Sequences During Reading: A Network Model Based on Theta Phase Coding

Revealing the neuronal mechanisms enabling the hippocampus to maintain episodic memory (i.e., memory for personal events) is a fundamental issue for our understanding of human intelligence. A temporal compression mechanism based on theta phase coding has been shown to be essential for the encoding of episodic memory occurring on a behavioral timescale (>a few seconds) and capable of operating sequential and spatial memory. However, episodic memory models should be developed to handle more semantic-rich contents. Here, memory from the reading of a passage of literature was evaluated using a network model based on theta phase coding. Two types of input were simultaneously applied: word inputs, defined by the eye movement sequence obtained during the reading, with each fixated word encoded by a vector computed from a statistical language model with a large text corpus; and sequence inputs, defined by random activations and representing a gradually changing input pattern, independent of the eye movement. The results successfully demonstrated a memory generated by the word sequence from the 6-min reading session, and the memory network for the sequence input was shown to be essential for the retrieval. This result was characterized by a words-in-sequence structure in the network formed by theta phase coding, of which, the unidirectional connections among sequence units dominantly evoked the sequential activation, which further conveyed word unit activations through the unidirectional connections from the sequence to the word units. This suggests a general role for theta phase coding in the formation of episodic memory.

Why Narrating Changes Memory: A Contribution to an Integrative Model of Memory and Narrative Processes.

This paper aims to reflect on the relation between autobiographical memory (ME) and autobiographical narrative (NA), examining studies on the effects of narrating on the narrator and showing how studying these relations can make more comprehensible both memory's and narrating's way of working. Studies that address explicitly on ME and NA are scarce and touch this issue indirectly. Authors consider different trends of studies of ME and NA: congruency vs incongruency hypotheses on retrieving, the way of organizing memories according to gist or verbatim format and their role in organizing positive and negative emotional experiences, the social roots of ME and NA, the rules of conversation based on narrating. Analysis of investigations leads the Authors to point out three basic results of their research. Firstly, NA transforms ME because it narrativizes memories according to a narrative format. This means that memories, when are narrated, are transformed in stories (verbal language) and socialised. Secondly, the narrativization process is determined by the act of telling something within a communicative situation. Thus, relational situation of narrating act, by modifying the story, modifies also memories. The Authors propose the RE.NA.ME model (RElation, NArration, MEmory) to understand and study ME and NA. Finally, this study claims that ME and NA refer to two different types of processes having a wide area of overlapping. This is due to common social, developmental and cultural roots that make NA to include part of ME (narrative of memory) and ME to include part of NA (memory of personal events that have been narrated).

Impaired coherence of life narratives of patients with schizophrenia.

Self-narratives of patients have received increasing interest in schizophrenia since they offer unique material to study patients’ subjective experience related to their illness, in particular the alteration of self that accompanies schizophrenia. In this study, we investigated the life narratives and the ability to integrate and bind memories of personal events into a coherent narrative in 27 patients with schizophrenia and 26 controls. Four aspects of life narratives were analyzed: coherence with cultural concept of biography, temporal coherence, causal-motivational coherence and thematic coherence. Results showed that in patients cultural biographical knowledge is preserved, whereas temporal coherence is partially impaired. Furthermore, causal-motivational and thematic coherence are significantly impaired: patients have difficulties explaining how events have modeled their identity, and integrating different events along thematic lines. Impairment of global causal-motivational and thematic coherence was significantly correlated with patients’ executive dysfunction, suggesting that cognitive impairment observed in patients could affect their ability to construct a coherent narrative of their life by binding important events to their self. This study provides new understanding of the cognitive deficits underlying self-disorders in patients with schizophrenia. Our findings suggest the potential usefulness of developing new therapeutic interventions to improve autobiographical reasoning skills.

Collective memory and autobiographical memory: Similar but not the same

Sociologists and psychologists have independently identified the same general period in individual development for the formation of many memories. Yet the cross-disciplinary similarity is rarely recognized, because most psychologists study autobiographical memories of personal events, while sociologists focus on collective memories of national and world events. We examine autobiographical and collective memories together within a large national cross-section survey of Americans. Both types of memory are located primarily in the same broad period, identified here as ages 5–30 years. However, within that period, autobiographical personal memories as measured by cue-word associations typically refer to earlier ages, while collective memories assessed with a standard open-ended question typically refer to somewhat later ages. Other types of questions yield still other memory content and ages. Reconceptualizing the reminiscence bump or critical period reconciles these diverse results.

Social cognition in a case of amnesia with neurodevelopmental mechanisms.

Episodic–autobiographical memory (EAM) is considered to emerge gradually in concert with the development of other cognitive abilities (such as executive functions, personal semantic knowledge, emotional knowledge, theory of mind (ToM) functions, language, and working memory). On the brain level its emergence is accompanied by structural and functional reorganization of different components of the so-called EAM network. This network includes the hippocampal formation, which is viewed as being vital for the acquisition of memories of personal events for long-term storage. Developmental studies have emphasized socio-cultural-linguistic mechanisms that may be unique to the development of EAM. Furthermore it was hypothesized that one of the main functions of EAM is the social one. In the research field, the link between EAM and social cognition remains however debated. Herein we aim to bring new insights into the relation between EAM and social information processing (including social cognition) by describing a young adult patient with amnesia with neurodevelopmental mechanisms due to perinatal complications accompanied by hypoxia. The patient was investigated medically, psychiatrically, and with neuropsychological and neuroimaging methods. Structural high resolution magnetic resonance imaging revealed significant bilateral hippocampal atrophy as well as indices for degeneration in the amygdalae, basal ganglia, and thalamus, when a less conservative threshold was applied. In addition to extensive memory investigations and testing other (non-social) cognitive functions, we employed a broad range of tests that assessed social information processing (social perception, social cognition, social regulation). Our results point to both preserved (empathy, core ToM functions, visual affect selection, and discrimination, affective prosody discrimination) and impaired domains of social information processing (incongruent affective prosody processing, complex social judgments). They support proposals for a role of the hippocampal formation in processing more complex social information that likely requires multimodal relational handling.

Growing Up with Asperger’s Syndrome: Developmental Trajectory of Autobiographical Memory

Autobiographical memory (AM) and social cognition share common properties and both are affected in autism spectrum disorders (ASD). So far, most of the scant research in ASD has concerned adults, systematically reporting impairment of the episodic component. The only study to be conducted with children concluded that they have poorer personal semantic knowledge than typical developing children. The present study explores the development of both components of AM in an 8-year-old boy diagnosed with Asperger’s syndrome, based on three examinations in 2007, 2008, and 2010. On each occasion, he underwent a general neuropsychological assessment including theory of mind (ToM) tasks, and a specially designed AM task allowing us to test both the semantic and the episodic components for three lifetime periods (current year, previous year, and earlier years). We observed difficulties in strategic retrieval and ToM, with a significant improvement between the second and third examinations. Regarding AM, different patterns of performance were noted in all three examinations: (1) relative preservation of current year personal knowledge, but impairment for the previous and earlier years, and (2) impairment of episodic memory for the current and previous year, but performances similar to those of controls for the earlier years. The first pattern can be explained by abnormal forgetting and by the semanticization mechanism, which needs verbal communication and social interaction to be efficient. The second pattern suggests that the development of episodic memory only reached the stage of “event memory.” This term refers to memory for personal events lacking in details or spatiotemporal specificity, and is usually observed in children younger than five. We conclude that the abnormal functioning of social cognition in ASD, encompassing social, and personal points of view, has an impact on both components of AM.

“Family Stories” and Their Implications for Preschoolers’ Memories of Personal Events

Most adults experience childhood amnesia: They have very few memories of events prior to 3 to 4 years of age. Nevertheless, some early memories are retained. Multiple factors likely are responsible for the survival of early childhood memories, including external representations such as videos, photographs, and conversations about past experiences, which help sustain memories over time. The present research was an experimental test of whether repeated recounting of past events influences young children's recall during a year delay. Twenty-four mothers and their 4-year-old children talked repeatedly about two randomly selected personal events that were assigned to become family-story events. Mothers were asked not to initiate conversations about two other randomly selected events (control events). A year later, children were interviewed by an experimenter about all four events. In free recall, children retrieved more of the family-story than the control events. With the aid of Wh- questions, levels of retrieval no longer differed. Moreover, the completeness and organization of children's narratives did not depend on whether they were about family-story or control events. The pattern of results suggests that repeated conversations about a past event help to maintain accessibility of the memory but may not substantially impact the integrity of the memory trace itself. The role of family stories in children's social and autobiographical memory development is discussed.

Identity-related autobiographical memories and cultural life scripts in patients with Borderline Personality Disorder

Disturbed identity is one of the defining characteristics of Borderline Personality Disorder manifested in a broad spectrum of dysfunctions related to the self, including disturbances in meaning-generating self-narratives. Autobiographical memories are memories of personal events that provide crucial building-blocks in our construction of a life-story, self-concept, and a meaning-generating narrative identity. The cultural life script represents culturally shared expectations as to the order and timing of life events in a prototypical life course within a given culture. It is used to organize one's autobiographical memories. Here, 17 BPD-patients, 14 OCD-patients, and 23 non-clinical controls generated three important autobiographical memories and their conceptions of the cultural life script. BPD-patients reported substantially more negative memories, fewer of their memories were of prototypical life script events, their memory narratives were less coherent and more disoriented, and the overall typicality of their life scripts was lower as compared with the other two groups.

The unpredictable past: Spontaneous autobiographical memories outnumber autobiographical memories retrieved strategically

Involuntary autobiographical memories are spontaneously arising memories of personal events, whereas voluntary memories are retrieved strategically. Voluntary remembering has been studied in numerous experiments while involuntary remembering has been largely ignored. It is generally assumed that voluntary recall is the standard way of remembering, whereas involuntary recall is the exception. However, little is known about the actual frequency of these two types of remembering in daily life. Here, 48 Danish undergraduates recorded their involuntary versus voluntary autobiographical memories during a day using a mechanical counter. Involuntary memories were reported three times as frequently as voluntary memories. Compared to voluntary memories, they were associated less with problem solving and social sharing and more with day dreaming, periods of boredom, no reasons for remembering and predominantly came to mind during unfocused attention. The findings suggest that involuntary recall is a typical way of accessing the personal past.

Current concerns in involuntary and voluntary autobiographical memories

Involuntary autobiographical memories are conscious memories of personal events that come to mind with no preceding attempts at retrieval. It is often assumed that such memories are closely related to current concerns--i.e., uncompleted personal goals. Here we examined involuntary versus voluntary (deliberately retrieved) autobiographical memories in relation to earlier registered current concerns measured by the Personal Concern Inventory (PCI; Cox & Klinger, 2000). We found no differences between involuntary and voluntary memories with regard to frequency or characteristics of current concern-related contents. However, memories related to current concerns were rated as more central to the person's identity, life story and expectations for the future than non-concern-related memories, irrespective of mode of recall. Depression and PTSD symptoms correlated positively with the proportion of current concern-related involuntary and voluntary memories. The findings support the view that involuntary and voluntary remembering is subject to similar motivational constraints.

Simulation of Human Episodic Memory by Using a Computational Model of the Hippocampus

The episodic memory, the memory of personal events and history, is essential for understanding the mechanism of human intelligence. Neuroscience evidence has shown that the hippocampus, a part of the limbic system, plays an important role in the encoding and the retrieval of the episodic memory. This paper reviews computational models of the hippocampus and introduces our own computational model of human episodic memory based on neural synchronization. Results from computer simulations demonstrate that our model provides advantage for instantaneous memory formation and selective retrieval enabling memory search. Moreover, this model was found to have the ability to predict human memory recall by integrating human eye movement data during encoding. The combined approach between computational models and experiment is efficient for theorizing the human episodic memory.