A conceptual space for episodic and semantic memory

Autobiographical phenomenology of memories of fiction

Most autobiographical memories are based on real-life experiences, but memories of fiction have many similarities to real-life autobiographical memories. However, the phenomenological nature of this similarity, the potential differences between media types, and the role of individual differences need further investigation. Based on previous findings, we expected differences between media types on emotional intensity, sensory vividness, and confidence about the recall. To provide insight into these issues, we collected one real-life autobiographical memory and one memory of fiction (book, film, or video game) from 291 participants. We asked them to rate their memories phenomenologically. The participants also provided information regarding their motivations for engaging with fictional stories. Our results show phenomenological differences in several dimensions between media types and differences in the similarity of media types to real-life memories. While absorption seems to be a good predictor for immersion, escapism tendency is a motivation to engage with fiction frequently.

The shared and unique neural correlates of personal semantic, general semantic, and episodic memory

One of the most common distinctions in long-term memory is that between semantic (i.e., general world knowledge) and episodic (i.e., recollection of contextually specific events from one's past). However, emerging cognitive neuroscience data suggest a surprisingly large overlap between the neural correlates of semantic and episodic memory. Moreover, personal semantic memories (i.e., knowledge about the self and one's life) have been studied little and do not easily fit into the standard semantic-episodic dichotomy. Here, we used fMRI to record brain activity while 48 participants verified statements concerning general facts, autobiographical facts, repeated events, and unique events. In multivariate analysis, all four types of memory involved activity within a common network bilaterally (e.g., frontal pole, paracingulate gyrus, medial frontal cortex, middle/superior temporal gyrus, precuneus, posterior cingulate, angular gyrus) and some areas of the medial temporal lobe. Yet the four memory types differentially engaged this network, increasing in activity from general to autobiographical facts, from autobiographical facts to repeated events, and from repeated to unique events. Our data are compatible with a component process model, in which declarative memory types rely on different weightings of the same elementary processes, such as perceptual imagery, spatial features, and self-reflection.

Memory of Fictional Information: A Theoretical Framework

Much of the information people encounter in everyday life is not factual; it originates from fictional sources, such as movies, novels, and video games, and from direct experience such as pretense, role-playing, and everyday conversation. Despite the recent increase in research on fiction, there is no theoretical account of how memory of fictional information is related to other types of memory or of which mechanisms allow people to separate fact and fiction in memory. We present a theoretical framework that places memory of fiction in relation to other cognitive phenomena as a distinct construct and argue that it is an essential component for any general theory of human memory. We show how fictionality can be integrated in an existing memory model by extending Rubin's dimensional conceptual memory model. By this means, our model can account for explicit and implicit memory of fictional information of events, places, characters, and objects. Further, we propose a set of mechanisms involving various degrees of complexity and levels of conscious processing that mostly keep fact and fiction separated but also allow information from fiction to influence real-world attitudes and beliefs: content-based reasoning, source monitoring, and an associative link from the memory to the concept of fiction.

Semantic-to-autobiographical memory priming is ubiquitous

It is now well established that the activation of semantic memories leads to the activation of autobiographical memories. Studies have shown that semantic processing of words or pictures primes autobiographical memories on voluntary and involuntary autobiographical memory tasks (the Crovitz cue-word task and the vigilance task). Known as semantic-to-autobiographical memory priming, our goal in the current study was to demonstrate the ubiquitous nature of this form of priming by showing that a wide variety of stimuli will prime involuntary autobiographical memories on the vigilance task. In Experiment 1, semantic-to-autobiographical priming was obtained on the vigilance task following the processing of sounds (e.g., the sound of bowling) and spoken words (e.g., the word bowling). In Experiment 2, semantic-to-autobiographical priming was observed on the vigilance task following tactile processing (e.g., the objects ball, glasses) and visual word processing (e.g., the words ball, glasses). In Experiment 3, semantic-to-autobiographical priming was observed on the vigilance task following the processing of videos (e.g., videos of a marching parade) and visual word processing (e.g., the word parade). The results of these experiments support the idea that semantic-to-autobiographical activations occur across a wide variety of stimuli (e.g., linguistic, perceptual). The results also further support the idea that semantic-to-autobiographical memory priming may play an important role in the production of involuntary memories in everyday life. Additional implications (for priming theory and autobiographical memory functions) are discussed.

Knowledge-based intervention improves older adult recognition memory for novel activity, but not event segmentation or temporal order memory

Although episodic memory declines with age, older adults are often able to make use of relevant knowledge to support episodic memory. More specifically, prior knowledge may support the perception of meaningful events through the process of event segmentation. We sought to test whether increasing older adults' knowledge for novel activities (i.e., Tai chi, making gyozas) would improve segmentation and memory. We conducted an online, pre-registered intervention in which eighty older adults were recruited based on being novices in each of the targeted activities. Participants completed segmentation and memory tests before and after being randomly assigned to one of two interactive virtual workshops (learning how to practice Tai chi or make gyozas). Each workshop consisted of two one-hour sessions during which an expert provided information about the activity and demonstrated it in a step-by-step fashion. We found that the intervention led to increased learning and recognition memory for the trained activity; however, there were no significant improvements in segmentation behavior, free recall, or memory of sequential information. These findings indicate that either more knowledge training is necessary to affect segmentation, or that segmentation is guided by perceptual features in the environment rather than one's conceptual understanding of the activity.

A virtual reality paradigm with dynamic scene stimuli for use in memory research

Episodic memory may essentially be memory for one's place within a temporally unfolding scene from a first-person perspective. Given this, pervasively used static stimuli may only capture one small part of episodic memory. A promising approach for advancing the study of episodic memory is immersing participants within varying scenes from a first-person perspective. We present a pool of distinct scene stimuli for use in virtual environments and a paradigm that is implementable across varying levels of immersion on multiple virtual reality (VR) platforms and adaptable to studying various aspects of scene and episodic memory. In our task, participants are placed within a series of virtual environments from a first-person perspective and guided through a virtual tour of scenes during a study phase and a test phase. In the test phase, some scenes share a spatial layout with studied scenes; others are completely novel. In three experiments with varying degrees of immersion, we measure scene recall, scene familiarity-detection during recall failure, the subjective experience of déjà vu, the ability to predict the next turn on a tour, the subjective sense of being able to predict the next turn on a tour, and the factors that influence memory search and the inclination to generate candidate recollective information. The level of first-person immersion mattered to multiple facets of episodic memory. The paradigm presents a useful means of advancing mechanistic understanding of how memory operates in realistic dynamic scene environments, including in combination with cognitive neuroscience methods such as functional magnetic resonance imaging and electrophysiology.

Taking the unreal seriously: enriching cognitive science with the notion of fictionality

Fictionality and fictional experiences are ubiquitous in people's everyday lives in the forms of movies, novels, video games, pretense and role playing, and digital technology use. Despite this ubiquity, though, the field of cognitive science has traditionally been dominated by a focus on the real world. Based on the limited understanding from previous research on questions regarding fictional information and the cognitive processes for distinguishing reality from fiction, we argue for the need for a comprehensive and systematic account that reflects on related phenomena, such as narrative comprehension or imagination embedded into general theories of cognition. This is important as incorporating cognitive processing of fictional events into memory theory reshapes the conceptual map of human memory. In this paper, we highlight future challenges for the cognitive studies of fictionality on conceptual, neurological, and computational levels. Taking on these challenges requires an interdisciplinary approach between fields like developmental psychology, philosophy, and the study of narrative comprehension. Our aim is to build on such interdisciplinarity and provide conclusions on the ways in which new theoretical frameworks of fiction cognition can aid understanding human behaviors in a wide range of aspects of people's daily lives, media consumption habits, and digital encounters. Our account also has the potential to inform technological innovations related to training intelligent digital systems to distinguish fact and fiction in the source material.

Opening a conceptual space for metamemory experience

The experiences associated with remembering, including metamemory feelings about the act of remembering and attempts at remembering, are not often integrated into general accounts of memory. For example, David Rubin (2022) proposes a unified, three-dimensional conceptual space for mapping memory states, a map that does not systematically specify metamemory feelings. Drawing on Rubin's model, we define a distinct role for metamemory in relation to first-order memory content. We propose a fourth dimension for the model and support the proposal with conceptual, neurocognitive, and clinical lines of reasoning. We use the modified model to illustrate several cases, and show how it helps to conceptualize a new category of memory state: autonoetic knowing, exemplified by déjà vu. We also caution not to assume that memory experience is directly correlated with or caused by memory content, an assumption Tulving (1989) labeled the doctrine of concordance.

Tonic immobility (freezing) during sexual and physical assaults produces stronger memory effects than other characteristics of the assaults

Tonic immobility (TI) is a phylogenetically conserved, passive, obligatory defense mechanism commonly engaged during sexual and physical assaults. During TI, people become immobile while remaining conscious and later reexperience intrusive memories of both their assault and of its accompanying immobility. Here we show that this well-studied biological process has powerful effects on memory and other processes. Participants had experienced either a serious sexual (n = 234) or physical (n = 137) assault. For both the assault and its accompanying immobility, the standard measure of the peritraumatic severity of TI correlated between .40 and .65 with post-assault effects on memory, including memory of the assault and memory of the immobility, the two memory-based self-concept measures of self-blame and event centrality, and post-assault anxiety and depression. The correlations with TI were much higher than other peritraumatic characteristics commonly used to predict and describe posttraumatic effects in assaults and other traumas. The results suggest that TI should be considered for a broader, more biologically based and ecologically valid understanding of the effects of trauma on memory and memory-based reactions.

Episodic Events as Spatiotemporal Memory: The Sequence of Information in the Episodic Buffer of Working Memory for Language Comprehension

Memory and language are the two higher-order cognitive abilities intertwined for communication and other cognitive skills. Memory is the storage capacity of all the information we perceive. Where the sensory memory perceives the stimuli, the working memory actively stores the information and passes it to the long-term memory. However, there is a question that how is the continuous perception of stimuli transformed into meaningful information and organized for proper execution and retrieval from the memory? This paper focuses on the episodic memory that perceives information that is spatial and temporal based on our everyday experiences. Though the spatiotemporal information we receive is continuous; the episodic memory arranges the information as to episodes in the working memory before the information is stored for a longer period. The episodic buffer is one of the components of the working memory model which holds the episodic memory that is organized concerning time. To this point, the paper tries to understand the working of the episodic buffer in maintaining the episodic memory and also about the process of episodic events into meaningful units. Further, the paper also concentrates on the hippocampus which is considered to be the location of the episodic buffer.

Lifespan effects of current age and of age at the time of remembered events on the affective tone of life narrative memories: Early adolescence and older age are more negative

The affective tone of autobiographical memories may be influenced by age in two ways-by the current age of the remembering individual and by the age of the remembered self at the time of the remembered event. While aging has been associated with more positive autobiographical memories, young adulthood is remembered more positively than other parts of life. We tested whether these effects also show in life story memories and how they act jointly on affective tone; also, we wanted to explore their effects on remembered lifetimes other than early adulthood. We tested effects of current age and age at event on affective tone with brief entire life narratives provided up to five times across 16 years by 172 Germans of both genders, ages 8 to 81 years. Multilevel analyses found an unexpected negativity effect of aging for current age and confirmed a "golden 20s" effect of remembered age. In addition, women told more negative life stories, and affective tone dipped in early adolescence for current age and was remembered as such up to mid-adulthood. Thus, the affective tone of life story memories is jointly influenced by current and remembered age. The absence of a positivity effect in aging is explained by the specific requirements of telling an entire life. We suggest the turmoil of puberty as a reason for the early adolescence dip. Gender differences are potentially explained by differences in narrative style, in depression rates, and in real-life challenges.

Chunking, boosting, or offloading? Using serial position to investigate long-term memory's enhancement of verbal working memory performance

Individuals can use information stored in episodic long-term memory (LTM) to optimize performance in a working memory (WM) task, and the WM system negotiates the exchange of information between WM and LTM depending on the current memory load. In this study, we assessed the ability of different accounts of interactions between LTM and WM to explain these findings, by investigating whether the position of pre-learnt information within a memory list encoded into WM affects the benefit it provides to immediate memory. In two experiments we varied the input position of previously learned word-word pairs within a set of four to-be-remembered pairs. We replicated previous findings of superior performance when these LTM pairs were included in the WM task and show that the position in the list in which these LTM pairs were included not seem to matter. These results are most consistent with the idea that having access to information in LTM reduces or removes the need to rely on WM for its storage, implying that people “offload” information in conditions containing LTM pairs.

Are involuntary autobiographical memory and déjà vu natural products of memory retrieval?

Involuntary autobiographical memories (IAMs) and déjà vu are phenomena that occur spontaneously in daily life. IAMs are recollections of the personal past, whereas déjà vu is defined as an experience in which the person feels familiarity at the same time as knowing that the familiarity is false. We present and discuss the idea that both IAMs and déjà vu can be explained as natural phenomena resulting from memory processing and, importantly, are both based on the same memory retrieval processes. Briefly, we hypothesise that both can be described as "involuntary" or spontaneous cognitions, where IAMs deliver content and déjà vu delivers only the feeling of retrieval. We map out the similarities and differences between the two, making a theoretical and neuroscientific account for their integration into models of memory retrieval and how the autobiographical memory literature can explain these quirks of daily life and unusual but meaningful phenomena. We explain the emergence of the déjà vu phenomenon by relating it to well-known mechanisms of autobiographical memory retrieval, concluding that IAMs and déjà vu lie on a continuum.