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Ever since Tulving's influential 1985 article 'Memory and consciousness', it has become traditional to think of autonoetic consciousness as necessary for episodic memory. This paper questions this claim. Specifically, it argues that the construct of autonoetic consciousness lacks validity and that, even if it was valid, it would still not be necessary for episodic memory. The paper ends with a proposal to go back to a functional/computational characterization of episodic memory in which its characteristic phenomenology is a contingent feature of the retrieval process and, as a result, open to empirical scrutiny. The proposal also dovetails with recent taxonomies of memory that are independent of conscious awareness and suggests strategies to evaluate within- and between-individual variability in the conscious experience of episodic memories in human and non-human agents. This article is part of the theme issue 'Elements of episodic memory: lessons from 40 years of research'. [ABSTRACT FROM AUTHOR]

How do our bodies influence who we are? Recent research in cognitive neuroscience has examined consciousness associated with the self and related multisensory processing of bodily signals, the so-called bodily self-consciousness. A parallel line of research has highlighted the concept of the autobiographical self and the associated autonoetic consciousness, which enables us to mentally travel in time. The subjective re-experiencing of past episodes is described as re-living them from within or outside one’s body. In this brief perspective, I aim to explore the underlying characteristics of self-consciousness and its relation to bodily signals and episodic memory. I will outline some recent behavioral and neuroimaging evidence indicating that bodily cues play a fundamental role in autobiographical memory. Finally, I will discuss these emerging concepts regarding the current understanding of bodily-self, autobiographical-self, their links to self-consciousness, and suggest directions for future research.

Episodic memories are experienced as belonging to a self that persists in time. We review evidence concerning the nature of human episodic memory and of the sense of self and how these emerge during development, proposing that the younger child experiences a persistent self that supports a subjective experience of remembering. We then explore recent research in cognitive architectures for robotics that has investigated the possibility of forms of synthetic episodic and autobiographical memory. We show that recent advances in generative modeling can support an understanding of the emergence of self and of episodic memory, and that cognitive architectures which include a language capacity are showing progress towards the construction of a narrative self with autobiographical memory capabilities for robots. We conclude by considering the prospects for a more complete model of mental time travel in robotics and the implications of this modeling work for understanding human episodic memory and the self in time. This article is part of the theme issue 'Elements of episodic memory: lessons from 40 years of research'. [ABSTRACT FROM AUTHOR]

\nIntroduction: Beyond the memory deficits classically observed in individuals with alcohol use disorder (IwAUD), research has recently focused on the study of autobiographical memory (AM) processes in IwAUD by analysing the content of AM narratives, and the implications for self-conception have been discussed. However, little is known about how IwAUD subjectively experience autobiographical recall. Methods: Thirty-seven IwAUD and 37 control participants were invited to perform an AM task that involved recalling memories for 4 life periods (2 important memories per period). Then, they assessed their subjective experience during AM recall using 6 phenomenological scales evaluating emotional valence, emotional intensity, sensory details, distancing, sharing, and vividness. Anxiety and depression symptoms, interoceptive sensibility, and difficulties in emotion regulation were also measured. Results: The IwAUD experienced greater distancing during AM recall, except during childhood AM recall, indicating that IwAUD are more prone to feeling that the person they are today is different from the person in their retrieved AMs. Very few intergroup differences were observed for AMs from childhood, adolescence-young adulthood, and adulthood, and a greater number of differences were observed for AMs from the last year: the IwAUD experienced AMs with a more negative valence, greater emotional intensity, fewer sensory details, greater distancing, and less sharing. A positive correlation was observed between distancing and interoceptive sensibility in the IwAUD group. Conclusion: Although these results suggest good preservation of autonoetic consciousness in IwAUD, except for more recent AMs, it is insufficient for IwAUD to experience a sense of self-continuity. This difficulty in maintaining a continuous sense of self may constitute a risk for AUD relapse. Beyond the memory deficits classically observed in individuals with alcohol use disorder (IwAUD), research has recently focused on the study of autobiographical memory (AM), which is the memory of personal experiences and facts about the self. By analysing the content of AM narratives in IwAUD, recent studies have reported a degradation of AMs content that may impact the self-conception of IwAUD. However, little is known about how IwAUD subjectively experience autobiographical recall. Thirty-seven IwAUD and 37 control participants were invited to perform an AM task that involved recalling memories for 4 life periods (2 important memories per period) and to assess their subjective experience during AM recall using 6 phenomenological scales. Anxiety and depression symptoms, interoceptive sensibility, and difficulties in emotion regulation were also measured. The IwAUD were more likely to feel that the person they are today is different from the person in their retrieved AMs (greater distancing), except during childhood AM recall. Very few intergroup differences were observed for AMs from childhood, adolescence-young adulthood, and adulthood, and a greater number of differences were observed for AMs from the last year: the IwAUD experienced AMs with a more negative valence, greater emotional intensity, fewer sensory details, greater distancing, and less sharing. A positive correlation was observed between distancing and interoceptive sensibility in the IwAUD group, indicating that the greater their interoceptive sensibility was, the more the IwAUD felt that they were a different person from the person in their AMs. [ABSTRACT FROM AUTHOR]

The idea that episodic memory is distinguished from semantic memory by the fact that it involves autonoetic consciousness, initially introduced by Tulving, has been influential not only in psychology but also in philosophy, where a variety of approaches to autonoesis and to its relationship to episodicity have been developed. This article provides a critical review of the available philosophical approaches. Distinguishing among representational, metacognitive, and epistemic accounts of autonoesis, it considers these in relation to objective and subjective conceptions of episodicity and assesses them against immediacy and source criteria that any philosophical account of autonoesis should arguably aim to satisfy. This article is categorized under:Philosophy > Psychological CapacitiesPhilosophy > ConsciousnessPsychology > Memory [ABSTRACT FROM AUTHOR]

This study aimed to investigate whether people with borderline personality disorder (BPD) can benefit from reliving positive autobiographical memories in terms of mood and state self-esteem and elucidate the neural processes supporting optimal memory reliving. Particularly the role of vividness and brain areas involved in autonoetic consciousness were studied, as key factors involved in improving mood and state self-esteem by positive memory reliving. Women with BPD (N = 25), Healthy Controls (HC, N = 33) and controls with Low Self-Esteem (LSE, N = 22) relived four neutral and four positive autobiographical memories in an MRI scanner. After reliving each memory mood and vividness was rated. State self-esteem was assessed before and after the Reliving Autobiographical Memories (RAM) task. Overall, mood and state self-esteem were lower in participants with BPD compared to HC and LSE, but both the BPD and LSE group improved significantly after positive memory reliving. Moreover, participants with BPD indicated that they relived their memories with less vividness than HC but not LSE, regardless of valence. When reliving (vs reading) memories, participants with BPD showed increased precuneus and lingual gyrus activation compared to HC but not LSE, which was inversely related to vividness. Women with BPD seem to experience more challenges in reliving neutral and positive autobiographical memories with lower vividness and less deactivated precuneus potentially indicating altered autonoetic consciousness. Nevertheless, participants with BPD do benefit in mood and self-esteem from reliving positive memories. These findings underline the potential of positive autobiographical memory reliving and suggest that interventions may be further shaped to improve mood and strengthen self-views in people with BPD. • The therapeutic potential of positive memories was studied in Borderline Personality Disorder (BPD). • Women with BPD are compared to a healthy (HC) and low self-esteem control group (LSE). • Vividly reliving positive memories has the potential to improve mood and state self-esteem in women with BPD. • Lower overall vividness and less deactivated precuneus indicate more challenges in reliving for women with BPD. • There is scope for positive memory reliving in a clinical setting for individuals with BPD. [ABSTRACT FROM AUTHOR]

How do our bodies influence who we are? Recent research in cognitive neuroscience has examined consciousness associated with the self and related multisensory processing of bodily signals, the so-called bodily self-consciousness. A parallel line of research has highlighted the concept of the autobiographical self and the associated autonoetic consciousness, which enables us to mentally travel in time. The subjective re-experiencing of past episodes is described as re-living them from within or outside one's body. In this brief perspective, I aim to explore the underlying characteristics of self-consciousness and its relation to bodily signals and episodic memory. I will outline some recent behavioral and neuroimaging evidence indicating that bodily cues play a fundamental role in autobiographical memory. Finally, I will discuss these emerging concepts regarding the current understanding of bodily-self, autobiographical-self, their links to self-consciousness, and suggest directions for future research. [ABSTRACT FROM AUTHOR]

Episodic memory (EM) allows us to remember and relive past events and experiences and has been linked to cortical-hippocampal reinstatement of encoding activity. While EM is fundamental to establish a sense of self across time, this claim and its link to the sense of agency (SoA), based on bodily signals, has not been tested experimentally. Using real-time sensorimotor stimulation, immersive virtual reality, and fMRI we manipulated the SoA and report stronger hippocampal reinstatement for scenes encoded under preserved SoA, reflecting recall performance in a recognition task. We link SoA to EM showing that hippocampal reinstatement is coupled with reinstatement in premotor cortex, a key SoA region. We extend these findings in a severe amnesic patient whose memory lacked the normal dependency on the SoA. Premotor-hippocampal coupling in EM describes how a key aspect of the bodily self at encoding is neurally reinstated during the retrieval of past episodes, enabling a sense of self across time. This study describes a premotor-hippocampal coupling in episodic memory, revealing how the bodily sensory context and in particular the sense of agency of the observer at encoding is neurally reinstated during the retrieval of past episodes. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Although involuntary autobiographical memories (IAMs) and déjà vu have important shared characteristics, in this commentary, we focus on potential differences that may question the argument that two phenomena lie on a continuum. We propose that differences in their frequency and autonoetic consciousness could be explained by different types of cues and memory representations involved in experiencing IAMs and déjà vu. [ABSTRACT FROM AUTHOR]

Emerging evidence suggests that autobiographical memory (ABM) is altered in Huntington's disease (HD). While these impairments are typically attributed to frontostriatal dysfunction, the neural substrates of ABM impairment in HD remain unexplored. To this end, we assessed ABM in 30 participants with genetically confirmed HD (18 premanifest, 12 manifest) and 24 age-matched healthy controls. Participants completed the Autobiographical Interview to assess free and probed ABM recall and underwent structural brain imaging. Whole-brain voxel-based morphometry (VBM) was used to explore voxel-wise associations between ABM performance and grey matter intensity (False Discovery Rate corrected at q = 0.05). Relative to controls, HD participants displayed significantly less detailed ABM retrieval across free and probed recall conditions, irrespective of disease stage. Recall performance did not differ significantly between manifest and premanifest HD groups. VBM analyses indicated that poorer ABM performance was associated with atrophy of a distributed cortico-subcortical network. Key regions implicated irrespective of ABM condition included the bilateral occipital cortex, left precuneus, right parahippocampal gyrus and right caudate nucleus. In addition, probed ABM recall was associated with the superior and inferior frontal gyri, frontal pole, right hippocampus, nucleus accumbens, paracingulate gyrus and cerebellum. Overall, our findings indicate that ABM impairments in HD reflect the progressive degeneration of a distributed cortico-subcortical brain network comprising medial temporal, frontal, striatal and posterior parietal cortices. Our findings advance our understanding of the neurocognitive profile of HD, providing an important foundation for future interventions to support memory function in this population., (© 2024 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.)

This chapter reviews some directions along which Craig's proposal of subjective time as emergent from interoceptive and bodily dynamics allows to frame recent findings on prospective and retrospective time processing. Behavioral and neuroimaging evidence from prospective timing studies demonstrates that an interoceptive-insular system may support the development of a primary representation of time in the context of large-scale networks involved in duration processing. Studies showing a tight link between episodic memory and interoceptive, emotional, and sensorimotor states further provide insights on processes supporting retrospective timing. These lines of evidence show that acknowledging its dependence on bodily states is most likely a crucial step toward a mechanistic understanding of time perception., (© 2024. The Author(s), under exclusive license to Springer Nature Switzerland AG.)

Urbach-Wiethe disease is an extremely rare genetically-based syndrome which usually leads to dermatological and neurological changes. Neurologically, the amygdaloid region is primarily bilaterally affected. Therefore, several functions modulated by the amygdala are changed in patients with Urbach-Wiethe disease. As the neurological alterations evolve only gradually, it is particularly important to determine the cognitive and brain status of a juvenile. The patient described here was seen briefly at age 9 and tested neuropsychologically at age 19; furthermore, computer tomography and magnetic resonance imaging of his head was done. There were no important abnormalities in the brain, which is unusual in the light of previous data from other patients. On the cognitive level, the patient was generally within normal limits. However, he had mild problems in attention and concentration, and more prominent problems in emotional processing domain, and in personality dimensions. It is concluded that amygdala calcifications in Urbach-Wiethe disease take place progressively-possibly underpinned by genetic and gender variables; this can subsequently allow psychosocial-social factors (such a proper education and socialization) and biological factors (compensatory neuroplasticity) to retard and diminish the development of socio-emotional and cognitive deteriorations, though the outcome of questionnaires indicates that such patients may develop substantial concerns as to their future life and well-being. • Brain and behavior of a man with a rare, genetically based disease were investigated. • The patient was young (19-years) and had Urbach-Wiethe disease. • The patient was cognitively intact, but showed emotional and personality changes. • Contrary to most patients with Urbach-Wiethe disease he showed no amygdala changes. • Education, gender, and a possible gene variation might have retarded amygdala damage. [ABSTRACT FROM AUTHOR]

The qualities of remembered experiences are often used to inform "reality monitoring" judgments, our ability to distinguish real and imagined events. Previous experiments have tended to investigate only whether reality monitoring decisions are accurate or not, providing little insight into the extent to which reality monitoring may be affected by qualities of the underlying mnemonic representations. We used a continuous-response memory precision task to measure the quality of remembered experiences that underlie two different types of reality monitoring decisions: self/experimenter decisions that distinguish actions performed by participants and the experimenter and imagined/perceived decisions that distinguish imagined and perceived experiences. The data revealed memory precision to be associated with higher accuracy in both self/experimenter and imagined/perceived reality monitoring decisions, with lower precision linked with a tendency to misattribute self-generated experiences to external sources. We then sought to investigate the possible neurocognitive basis of these observed associations by applying brain stimulation to a region that has been implicated in precise recollection of personal events, the left angular gyrus. Stimulation of angular gyrus selectively reduced the association between memory precision and self-referential reality monitoring decisions, relative to control site stimulation. The angular gyrus may, therefore, be important for the mnemonic processes involved in representing remembered experiences that give rise to a sense of self-agency, a key component of "autonoetic consciousness" that characterizes episodic memory. [ABSTRACT FROM AUTHOR]

The assessment of autobiographical memory is challenging in clinical settings. The Autobiographical Fluency Task (AFT) - that is designed to test both Episodic Autobiographical Memory (EAM) and experience-near Personal Semantics (enPS) - may represent a feasible and rapid method to test access to autobiographical memories. Here we tested the reliability and the construct validity of the AFT. A total number of 51 individuals participated in the present study, with 24 included in Experiment 1 and 27 in Experiment 2. In Experiment 1, participants performed both the AFT and the Survey of Autobiographical Memory (SAM). In Experiment 2, participants completed the AFT and the Autobiographical Interview (AI). The AFT showed a moderate-to-high reliability. Also, EAM and enPS scores significantly correlated with the episodic subscale of the SAM. Results of Experiment 1 were replicated and expanded in Experiment 2. Again, the AFT showed a high reliability. Both EAM and enPS showed a significant correlation with the number of internal details produced during the AI; enPS also correlated with the number of external details. Overall, the present results show that the AFT may be a feasible instrument to assess autobiographical memory, especially for testing episodic autobiographical memory and experience-near personal semantics in clinical settings., (© 2023 The Authors. Journal of Neuropsychology published by John Wiley & Sons Ltd on behalf of The British Psychological Society.)

The essence of who we are depends on our brains. They enable us to think, to feel joy and sorrow, communicate through speech, reflect on the moments of our lives, and to anticipate, plan for, and worry about our imagined futures. Although some of our abilities are comparatively new, key features of our behavior have deep roots that can be traced to the beginning of life. By following the story of behavior, step-by-step, over its roughly four-billion-year trajectory, we come to understand both how similar we are to all organisms that have ever lived, and how different we are from even our closest animal relatives. We care about our differences because they are ours. But differences do not make us superior; they simply make us different. [ABSTRACT FROM AUTHOR]

Background: Cognitive networks impairments are common in neuropsychiatric disorders like Attention Deficit Hyperactivity Disorder (ADHD), bipolar disorder (BD), and schizophrenia (SZ). While previous research has focused on specific brain regions, the role of the procedural memory as a type of long-term memory to examine cognitive networks impairments in these disorders remains unclear. This study investigates alterations in resting-state functional connectivity (rs-FC) within the procedural memory network to explore brain function associated with cognitive networks in patients with these disorders. Methods: This study analyzed resting-state functional magnetic resonance imaging (rs-fMRI) data from 40 individuals with ADHD, 49 with BD, 50 with SZ, and 50 healthy controls (HCs). A procedural memory network was defined based on the selection of 34 regions of interest (ROIs) associated with the network in the Harvard-Oxford Cortical Structural Atlas (default atlas). Multivariate region of interest to region of interest connectivity (mRRC) was used to analyze the rs-FC between the defined network regions. Significant differences in rs-FC between patients and HCs were identified (P < 0.001). Results: ADHD patients showed increased Cereb45 l - Cereb3 r rs-FC (p = 0.000067) and decreased Cereb1 l - Cereb6 l rs-FC (p = 0.00092). BD patients exhibited increased rs-FC between multiple regions, including Claustrum r - Caudate r (p = 0.00058), subthalamic nucleus r - Pallidum l (p = 0.00060), substantia nigra l - Cereb2 l (p = 0.00082), Cereb10 r - SMA r (p = 0.00086), and Cereb9 r - SMA l (p = 0.00093) as well as decreased rs-FC in subthalamic nucleus r - Cereb6 l (p = 0.00013) and Cereb9 r - Cereb9 l (p = 0.00033). SZ patients indicated increased Caudate r– putamen l rs-FC (p = 0.00057) and decreased rs-FC in subthalamic nucleus r – Cereb6 l (p = 0.000063), and Cereb1 r – subthalamic nucleus r (p = 0.00063). Conclusions: This study found significant alterations in rs-FC within the procedural memory network in patients with ADHD, BD, and SZ compared to HCs. These findings suggest that disrupted rs-FC within this network may related to cognitive networks impairments observed in these disorders. Clinical trial number: Not applicable. [ABSTRACT FROM AUTHOR]

The hippocampus plays a critical role in the formation of declarative memories, and hippocampal damage leads to significant impairments in new memory formation. Drawing can serve as a form of multi-modal encoding that improves declarative memory performance relative to other multimodal encoding strategies such as writing. We examined whether, and to what extent, patients with hippocampal damage could benefit from the mnemonic strategy of drawing. Three patients with focal hippocampal damage, and one patient with both hippocampal and cortical lesions, in addition to 22 age-, sex-, and education-matched controls, were shown a list of words one at a time during encoding and instructed to either draw a picture or repeatedly write each word for 40 s. Following a brief filled delay, free recall and recognition memory for words from both encoding trial types were assessed. Controls showed enhanced recall and recognition memory for words drawn versus those that were written, an effect that was even more pronounced in patients with focal hippocampal damage. By contrast, the patient with both hippocampal and cortical lesions showed no drawing-mediated boost in either recall or recognition memory. These findings demonstrate that drawing is an effective encoding strategy, likely accruing from the engagement of extra-hippocampal processes including the integration of cortical-based motor, visual, and semantic processing, enabling more elaborative encoding. [ABSTRACT FROM AUTHOR]

Objective: Age-related hippocampal atrophy is associated with memory loss in older adults, and certain hippocampal subfields are more vulnerable to age-related atrophy than others. Cardiorespiratory fitness (CRF) may be an important protective factor for preserving hippocampal volume, but little is known about how CRF relates to the volume of specific hippocampal subfields, and whether associations between CRF and hippocampal subfield volumes are related to episodic memory performance. To address these gaps, the current study evaluates the associations among baseline CRF, hippocampal subfield volumes, and episodic memory performance in cognitively unimpaired older adults from the Investigating Gains in Neurocognition Trial of Exercise (IGNITE) (NCT02875301). Methods: Participants (N = 601, ages 65–80, 72% female) completed assessments including a graded exercise test measuring peak oxygen comsumption (VO2peak) to assess CRF, cognitive testing, and high-resolution magnetic resonance imaging of the hippocampus processed with Automated Segmentation of Hippocampal Subfields (ASHS). Separate linear regression models examined whether CRF was associated with hippocampal subfield volumes and whether those assocations were moderated by age or sex. Mediation models examined whether hippocampal volumes statistically mediated the relationship between CRF and episodic memory performance. Covariates included age, sex, years of education, body mass index, estimated intracranial volume, and study site. Results: Higher CRF was significantly associated with greater total left (B = 5.82, p = 0.039) and total right (B = 7.64, p = 0.006) hippocampal volume, as well as greater left CA2 (B = 0.14, p = 0.022) and dentate gyrus (DG; B = 2.34, p = 0.031) volume, and greater right CA1 (B = 3.99, p = 0.011), CA2 (B = 0.15, p = 0.002), and subiculum (B = 1.56, p = 0.004) volume. Sex significantly moderated left DG volume (B = −4.26, p = 0.017), such that the association was positive and significant only for males. Total left hippocampal volume [indirect effect = 0.002, 95% CI (0.0002, 0.00), p = 0.027] and right subiculum volume [indirect effect = 0.002, 95% CI (0.0007, 0.01), p = 0.006] statistically mediated the relationship between CRF and episodic memory performance. Discussion: While higher CRF was significantly associated with greater total hippocampal volume, CRF was not associated with all underlying subfield volumes. Our results further demonstrate the relevance of the associations between CRF and hippocampal volume for episodic memory performance. Finally, our results suggest that the regionally-specific effects of aging and Alzheimer's disease on hippocampal subfields could be mitigated by maintaining higher CRF in older adulthood. [ABSTRACT FROM AUTHOR]

Human imagination has garnered growing interest in many fields. However, it remains unclear how to characterize different forms of imaginative thinking and how imagination differs between young and older adults. Here, we introduce a novel scoring protocol based on recent theoretical developments in the cognitive neuroscience of imagination to provide a broad tool with which to characterize imaginative thinking. The scoring protocol distinguishes between concrete/perceptual forms of imagination termed the "mind's eye" and abstract/reflective forms of imagination termed the "mind's mind." The protocol also captures whether thoughts pertain to the self, others, or both. We applied this scoring protocol with high inter-rater reliability across two studies involving distinct participants and narrative-based imagination tasks. When compared to young adults, older adults showed a bias toward general content, which is a feature of the mind's mind form of thinking while describing aloud their memories of specific, past events (Study 1). Further, older adults made fewer references to the self. In a separate study of only older adults (Study 2), increasing age was not associated with a bias toward the mind's mind while describing specific past or future events. These results reveal that imaginative thinking can be characterized within the Mind's Eye Mind's Mind framework, with implications for understanding cognitively normal older age. [ABSTRACT FROM AUTHOR]

Patients with major depressive disorder (MDD) and borderline personality disorder (BPD) are reported to have disrupted autobiographical memory (AM). Using functional magnetic resonance imaging we investigated behavioral and neural processing of the recall of emotional (sad and happy) memories in 30 MDD, 18 BPD, and 34 healthy control (HC) unmedicated women. The behavioral results showed that the MDD group experienced more sadness than the HC after the sad recall, while BPD participants experienced less happiness than HC after the happy recall. The fMRI results for sad AMs, compared to happy AMs, elicited greater activation in multiple brain regions (i.e., medial prefrontal cortex, posterior cingulate cortex, insula) linked to self-related information, emotional processing, and semantic recollection across all groups. Functional connectivity analysis revealed a significant main effect of group between the occipital cortex and precuneus and between occipital cortex and posterior cingulate cortex. The effect was driven by stronger connectivity between the occipital cortex and precuneus in the clinical groups taken together than in the HC. Our results suggest a need for stronger coordination between visual imagery and contextual recall for vivid memory retrieval in these clinical groups. [ABSTRACT FROM AUTHOR]

NMDA receptor (NMDAR)-mediated calcium influx triggers the induction and initial expression of long-term potentiation (LTP). Here we report that in male rodents, ion flux-independent (metabotropic) NMDAR signaling is critical for a third step in the production of enduring LTP, i.e., cytoskeletal changes that stabilize the activity-induced synaptic modifications. Surprisingly, females rely upon estrogen receptor alpha (ERa) for the metabotropic NMDAR operations used by males. Blocking NMDAR channels with MK-801 eliminated LTP expression in hippocampal field CA1 of both sexes but left intact theta burst stimulation (TBS)-induced actin polymerization within dendritic spines. A selective antagonist (Ro25-6981) of the NMDAR GluN2B subunit had minimal effects on synaptic responses but blocked actin polymerization and LTP consolidation in males only. Conversely, an ERa antagonist thoroughly disrupted TBS-induced actin polymerization and LTP in females while having no evident effect in males. In an episodic memory paradigm, Ro25-6981 prevented acquisition of spatial locations by males but not females, whereas an ERa antagonist blocked acquisition in females but not males. Sex differences in LTP consolidation were accompanied by pronounced differences in episodic memory in tasks involving minimal (for learning) cue sampling. Males did better on acquisition of spatial information whereas females had much higher scores than males on tests for acquisition of the identity of cues (episodic "what") and the order in which the cues were sampled (episodic "when"). We propose that sex differences in synaptic processes used to stabilize LTP result in differential encoding of the basic elements of episodic memory. [ABSTRACT FROM AUTHOR]

The basolateral amygdala (BLA) is crucial for the encoding and expression of fear memory, yet it remains unexplored how neural activity in this region is dynamically influenced by distributed circuits across the brain to facilitate expression of fear memory of different ages. Using longitudinal multisite electrophysiological recordings in male mice, we find that the recall of older contextual fear memory is accompanied by weaker, yet more rhythmic, BLA gamma activity which is distally entrained by theta oscillations in both the hippocampal CA1 and the anterior cingulate cortex. Computational modeling with Light Gradient Boosting Machine using extracted oscillatory features from these three regions, as well as with Transformer using raw local field potentials, accurately classified remote from recent memory recall primarily based on BLA gamma and CA1 theta. These results demonstrate in a non-biased manner that multi-regional control of BLA activity serves as reliable neural signatures for memory age-dependent recall mechanisms. Differential neural dynamics in the amygdala that define recall of different ages of fear memory remain not fully understood. Here, the authors show by both experiments and modeling that multiregional control of amygdalar gamma activity encodes memory age. [ABSTRACT FROM AUTHOR]

Post-Traumatic Stress Disorder (PTSD) is a multifaceted psychiatric disorder triggered by traumatic events, leading to prolonged psychological distress and varied symptoms. Rat models have been extensively used to explore the biological, behavioral, and neurochemical underpinnings of PTSD. This review critically examines the strengths and limitations of commonly used rat models, such as single prolonged stress (SPS), stress–re-stress (S-R), and predator-based paradigms, in replicating human PTSD pathology. While these models provide valuable insights into neuroendocrine responses, genetic predispositions, and potential therapeutic targets, they face challenges in capturing the full complexity of PTSD, particularly in terms of ethological relevance and translational validity. We assess the degree to which these models mimic the neurobiological and behavioral aspects of human PTSD, highlighting areas where they succeed and where they fall short. This review also discusses future directions in refining these models to improve their utility for translational research, aiming to bridge the gap between preclinical findings and clinical applications. [ABSTRACT FROM AUTHOR]

Background: Borderline Personality Disorder (BPD) is a prevalent psychopathological condition, affecting 0.7–2.7% of the general population. Given the known link between identity formation and the temporal, metacognitive, and narrative processes that contribute to its coherence, the aim of the present systematic review is to synthesize the current literature about the relationship between identity diffusion and lived time in adult patients with BPD. This would enhance knowledge and treatments, leading to a better understanding of the implications of time processes on identity diffusion in BPD. Methods: According to PRISMA guidelines, the main databases were consulted, and specific eligibility criteria were applied. The selection leads to the inclusion of 15 articles, investigating through integrated techniques the lived time, memory, self-reported narratives, and metacognition in BPD subjects. Results: A general agreement among researchers was found, confirming greater difficulty for BPD subjects in producing autobiographical stories, logically and temporally integrated, characterized by positive content. Functional and structural alterations were detected to explain narrative incoherence, as well as symptoms such as emotional dysregulation and cognitive biases. Conclusions: The difficulty for BPD subjects in producing a coherent personal narrative has been interpreted as a correlation of anomalies in autobiographical memories and consequently identities, which were equally compromised by the experience of discontinuity in the temporal structure. This would confirm the hypothesis of the temporal fragmentation of the self in BPD. Although some limitations have been encountered, we suggest that the understanding of identity diffusion and lived time in BPD subjects could represent a useful guide for further research. [ABSTRACT FROM AUTHOR]

Background: Adequate sleep is essential for maintaining cognitive function, as evidenced by literature. Perilla frutescens var. acuta Kudo (PF) is a traditional medicinal herb reported to improve vascular cognitive impairment and induce sedation. However, the effects of PF on cognitive impairment caused by sleep deprivation (SD) have not yet been evaluated. This study aims to evaluate the effects of fermented PF (FPF) and its underlying mechanisms in a model of SD-induced cognitive impairment. Methods: Mice were subjected to SD to establish cognitive impairment, and FPF was administered once daily for 3 days. Cognitive performance was assessed using Y-maze and passive avoidance tests, followed by molecular mechanisms analyses. Results: FPF treatment improved SD-induced cognitive impairment, as evidenced by increased spontaneous alternation and extended latency time. Histological analysis revealed that SD impaired the hippocampus, and this impairment was alleviated by FPF treatment. FPF demonstrated antioxidant activity by increasing glutathione levels and decreasing malondialdehyde levels. Furthermore, the decreased levels of brain-derived neurotrophic factor (BDNF) observed in sleep-deprived mice were restored with FPF treatment. FPF also enhanced the phosphorylation of tropomyosin receptor kinase B, extracellular signal-regulated kinase, and cAMP response element-binding protein. Conclusions: These results indicate that FPF may have beneficial effects on SD-induced cognitive impairment by protecting against oxidative stress and increasing BDNF expression. [ABSTRACT FROM AUTHOR]

Autobiographical memory (AM) involves a rich phenomenological re-experiencing of a spatio-temporal event from the past, which is challenging to objectively quantify. The Autobiographical Interview (AI; Levine et al. Psychology and Aging, 17(4), 677-689, 2002) is a manualized performance-based assessment designed to quantify episodic (internal) and semantic (external) features of recalled and verbally conveyed prior experiences. The AI has been widely adopted, yet has not undergone a comprehensive psychometric validation. We investigated the reliability, validity, association to individual differences measures, and factor structure in healthy younger and older adults (N = 352). Evidence for the AI's reliability was strong: the subjective scoring protocol showed high inter-rater reliability and previously identified age effects were replicated. Internal consistency across timepoints was robust, suggesting stability in recollection. Central to our validation, internal AI scores were positively correlated with standard, performance-based measures of episodic memory, demonstrating convergent validity. The two-factor structure for the AI was not well supported by confirmatory factor analysis. Adjusting internal and external detail scores for the number of words spoken (detail density) improved trait estimation of AM performance. Overall, the AI demonstrated sound psychometric properties for inquiry into the qualities of autobiographical remembering., (© 2023. The Psychonomic Society, Inc.)

Background: Self-disorders constitute a core feature of the schizophrenia spectrum, including early stages such as first-episode psychosis (FEP). These disorders impact the minimal Self, or bodily self-consciousness, which refers to the basic, pre-reflective sense of embodied experience. The minimal Self is intrinsically linked to episodic memory, which captures specific past experiences of the Self. However, research on this relationship in the schizophrenia spectrum remains scarce. This pilot study aimed to investigate how the minimal Self modulated episodic memory of naturalistic events in FEP, using immersive virtual reality. A secondary objective was to examine the relationships between sense of Self, embodiment, episodic memory, schizotypal personality traits in healthy participants (CTL), and psychopathology in FEP. Methods: A full-body illusion was induced in 10 FEP and 35 matched CTL, using a first-person avatar, with synchronous or asynchronous visuomotor stimulation (strong or weak embodiment conditions, respectively). Following embodiment induction, participants navigated a virtual city and encountered naturalistic daily life events, which were incidentally encoded. Episodic memory of these events was assessed through a comprehensive recognition task (factual and contextual information, retrieval phenomenology). Sense of Self, schizotypal personality traits, and psychopathology were assessed via self-reported questionnaires or clinical assessments. Results: Synchronous visuomotor stimulation successfully induced a stronger sense of embodiment in both FEP and CTL. The strong embodiment condition was associated with reduced perceived virtual space occupation by the body in FEP. Under strong embodiment, FEP performed significantly worse than CTL in contextual information recognition, but their ratings for retrieval phenomenology were comparable to CTL. Conversely, under weak embodiment, FEP performed similarly to CTL in contextual information recognition, but they rated retrieval phenomenology significantly lower. For CTL, we observed a slight, though non-significant, enhancement in recognition memory under strong compared to weak embodiment. Additionally, higher schizotypy in CTL correlated with a diminished sense of Self and poorer episodic memory. Conclusions: Disturbances in the minimal Self in FEP are associated with episodic memory impairments. These findings emphasise the importance of targeting minimal Self-disorders in schizophrenia spectrum disorders, since episodic memory impairments may negatively affect patients' quality of life and psychosocial outcomes. Additionally, they support a fully dimensional model of schizotypy. [ABSTRACT FROM AUTHOR]

Background: There is growing evidence that atrial fibrillation (AF) is a risk factor for cognitive impairment (CI) and dementia in the presence or absence of stroke. The purpose of this study was to explore the mechanism of CI caused by AF. Methods: Eighteen male canines were randomly divided into a sham group, a pacing group, and a pacing + GW4869 group. An experimental model of AF was established by rapid atrial pacing (450 beats/min) for 2 weeks, and the sham group received pacemaker implantation without atrial pacing. The GW4869 group received an intravenous GW4869 injection (0.3 mg/kg, once a day) during pacing. All canines were locally injected with Ad-CD63-RFP in epicardial adipose tissue (EAT) to trace the exosomes. Ultracentrifugation was employed to isolate EAT-derived exosomes, followed by RNA sequencing and quantitative real-time PCR (qRT-PCR) to assess RNA in both exosomes and hippocampal tissue. The miRanda database was used to predict the targeting relationships between miRNA and mRNA, which were further validated by luciferase reporter assays. Western blot analysis was conducted to detect exosomal markers (CD63, CD81, TSG101) in EAT exosomes, while immunofluorescence was used to detect Ad-CD63-RFP signals in both EAT and hippocampal tissues, as well as microglial activation marker IBA-1. To further explore the effects of exosomes on microglial cells, in vitro experiments using brain microvascular endothelial cells (bEnd3) and microglial cells (BV2) were conducted. IBA-1 expression and RNA levels in BV2 cells were analyzed by immunofluorescence and qRT-PCR, respectively. Results: After 14 days of pacing of the canine atrium, compared to the sham group, both the pacing and GW4869 groups exhibited an increased number of AF inductions, along with prolonged AF duration. The fluorescence intensity of Ad-CD63-RFP and the microglial activation marker IBA-1 were markedly greater in the hippocampus. RNA sequencing showed that the differentially expressed gene cfa-miR-22e in EAT exosomes was upregulated, and its target gene IL33 was downregulated in the hippocampus. qRT-PCR showed that the levels of cfa-miR-22e were increased in both EAT exosomes and the hippocampus, while the expression of IL-33, a target of cfa-miR-22e, was decreased in the hippocampus. The administration of GW4869 abolished these effects. The in vitro results from bEnd3 and BV2 cell experiments were consistent with the conclusions drawn from the in vivo studies. Conclusion: Our study indicated that the exosomes secreted by EAT in canines with AF can penetrate the BBB and activate microglia in the hippocampus through the cfa-miR-22e/IL33 signalling pathway. [ABSTRACT FROM AUTHOR]

Mental time travel (MTT), a cornerstone of human cognition, enables individuals to mentally project themselves into their past or future. It was shown that this self-projection may extend beyond the temporal domain to the spatial and social domains. What about higher cognitive domains? Twenty-eight participants underwent functional magnetic resonance imaging (fMRI) while self-projecting to different political, moral and temporal perspectives. For each domain, participants were asked to judge their relationship to various people (politicians, moral figures, personal acquaintances) from their actual or projected self-location. Findings showed slower, less accurate responses during self-projection across all domains. fMRI analysis revealed self-projection elicited brain activity at the precuneus, medial and dorsolateral prefrontal cortex, temporoparietal junction and anterior insula, bilaterally and right lateral temporal cortex. Notably, 23.5% of active voxels responded to all three domains and 27% to two domains, suggesting a shared brain system for self-projection. For ordinality judgement (self-reference), 52.5% of active voxels corresponded to the temporal domain specifically. Self-projection activity overlapped mostly with the frontoparietal control network, followed by the default mode network, while self-reference showed a reversed pattern, demonstrating MTT's implication in spontaneous brain activity. MTT may thus be regarded as a 'mental-experiential travel', with self-projection as a domain-general construct and self-reference related mostly to time. This article is part of the theme issue 'Elements of episodic memory: lessons from 40 years of research'. [ABSTRACT FROM AUTHOR]

In Tulving's initial characterization, episodic memory was one of multiple memory systems. It was postulated, in pursuit of explanatory depth, as displaying proprietary operations, representations and substrates such as to explain a range of cognitive, behavioural and experiential phenomena. Yet the subsequent development of this research programme has, paradoxically, introduced surprising doubts about the nature, and indeed existence, of episodic memory. On dominant versions of the 'common system' view, on which a single simulation system underlies both remembering and imagining, there are no processes unique to memory to support robust generalizations with inductive potential. Eliminativism about episodic memory seems to follow from the claim that it has no dedicated neurocognitive system of its own. After identifying this under-noticed threat, we push back against modern eliminativists by surveying recent evidence that still indicates specialized mechanisms, computations and representations that are distinctly mnemic in character. We argue that contemporary realists about episodic memory can retain lessons of the common system approach while resisting the further move to eliminativism. This article is part of the theme issue 'Elements of episodic memory: lessons from 40 years of research'. [ABSTRACT FROM AUTHOR]

In this article, we explore various arguments against the traditional distinction between episodic and semantic memory based on the metaphysical phenomenon of transitional gradation. Transitional gradation occurs when two candidate kinds A and B grade into one another along a continuum according to their characteristic properties. We review two kinds of arguments—from the gradual semanticization of episodic memories as they are consolidated, and from the composition of episodic memories during storage and recall from semantic memories—that predict the proliferation of such transitional forms. We further explain why the distinction cannot be saved from the challenges of transitional gradation by appealing to distinct underlying memory structures and applying our perspective to the impasse over research into 'episodic-like' memory in non-human animals. On the whole, we recommend replacing the distinction with a dynamic life cycle of memory in which a variety of transitional forms will proliferate, and illustrate the utility of this perspective by tying together recent trends in animal episodic memory research and recommending productive future directions. This article is part of the theme issue 'Elements of episodic memory: lessons from 40 years of research'. [ABSTRACT FROM AUTHOR]

The concept of episodic memory (EM) faces significant challenges by two claims: EM might not be a distinct memory system, and EM might be an epiphenomenon of a more general capacity for mental time travel (MTT). Nevertheless, the observations leading to these arguments do not preclude the existence of a mechanically and functionally distinct EM system. First, modular systems, like cognition, can have distinct subsystems that may not be distinguishable in the system's final output. EM could be such a subsystem, even though its effects may be difficult to distinguish from those of other subsystems. Second, EM could have a distinct and consistent low-level function, which is used in diverse high-level functions such as MTT. This article introduces the scenario construction framework, proposing that EM crucially rests on memory traces containing the gist of an episodic experience. During retrieval, EM traces trigger the reconstruction of semantic representations, which were active during the remembered episode, and are further enriched with semantic information, to generate a scenario of the past experience. This conceptualization of EM is consistent with studies on the neural basis of EM and resolves the two challenges while retaining the key properties associated with EM. This article is part of the theme issue 'Elements of episodic memory: lessons from 40 years of research'. [ABSTRACT FROM AUTHOR]

Tulving's concept of mental time travel (MTT), and the related distinction of episodic and semantic memory, have been highly influential contributions to memory research, resulting in a wealth of findings and a deeper understanding of the neurocognitive correlates of memory and future thinking. Many models have conceptualized episodic and semantic representations as existing on a continuum that can help to account for various hybrid forms. Nevertheless, in most theories, MTT remains distinctly associated with episodic representations. In this article, we review existing models of memory and future thinking, and critically evaluate whether episodic representations are distinct from other types of explicit representations, including whether MTT as a neurocognitive capacity is uniquely episodic. We conclude by proposing a new framework, the Multidimensional Model of Mental Representations (MMMR), which can parsimoniously account for the range of past, present and future representations the human mind is capable of creating. This article is part of the theme issue 'Elements of episodic memory: lessons from 40 years of research'. [ABSTRACT FROM AUTHOR]