Memory Content Research Articles

The Relationship between Faith and Knowledge in the Works of Mykhailo Maksymovych

The paper deals with images of faith and knowledge in the works of Mykhailo Maksymovych, a famous botanist, folklorist, and historian of the 19th century and the first rector of the University of Saint Volodimir in Kyiv. Mykhailo Maksymovych’s way of solving the problem of the relationship between religion and science is analysed in the general context of the intellectual processes in Eastern Europe of the 19th century. The study is based on Mykhailo Maksymovych’s published works, memoirs, letters, and unpublished texts, held in the Institution of Manuscript at the Vernadsky National Library of Ukraine (Kyiv). The methodological foundation is the approaches of the Cambridge School of Intellectual History, theorising on cultural memory and quantitative content analysis with MAXQDA-2022. The paper shows that Mykhailo Maksymovych’s attitude to the demarcation problem of knowledge and faith resulted from a combination of his personal religiosity and his fascination with the ideas of Friedrich Schelling. Mykhailo Maksymovych perceived the Bible as a relevant description of the “factual” dimension of human history. He represented the philosophy of the heart, widespread in Ukrainian intellectual life of that period. Maksymovych’s deep personal religiosity, combined with his theoretical ideas about the correlation between faith and knowledge, led him to the idea of Orthodox coherence between Russia and Ukraine. This was an actualisation of the early modern idea, elaborated in the Kyivan Synopsis of the late 17th century. Mykhailo Maksymovych actualised these ideas on the basis of Romanticism. Early modern ideas were close to Maksymovych’s consciousness because he was religious in the traditional Orthodox sense. Religious images of Ukraine in the works of Mykhailo Maksymovych were similar to the ideas of Konstantin Leontiev, a famous Russian conservative philosopher of the second half of the 19th century.

Integration of history information Drives Serial Dependence and Stabilizes Working Memory Representations.

Serial dependence has shown seemingly contradictory effects on visual perception and working memory. While serial dependence promotes perpetual and mnemonic stability, it biases behavioral reports toward prior information. The neural mechanisms that drive both biasing and adaptive stabilizing effects are not well understood. We proposed and tested a reactivation and integration mechanism that can account for these contradictory effects. We used multivariate pattern analyses of EEG data (26 human participants, 17 females, 9 males) to examine the reactivation of prior reported orientation during the delay period of a visual working memory task. The reactivation strength of prior reports, but not prior sensory items, was predictive of the magnitude of serial dependency biases. These reactivated representations integrated with the representation of the current memory item and improved the ability to decode the current contents of memory. Overall, our data provide convergent evidence suggesting that prior reports in a visual working memory task are reactivated on the subsequent trial and become integrated with current memory representations. This similarity-dependent reactivation mechanism drives both report biasing and stabilization effects attributed to serial dependence in working memory.

Neuronal representation of visual working memory content in the primate primary visual cortex.

The human ability to perceive vivid memories as if they "float" before our eyes, even in the absence of actual visual stimuli, captivates the imagination. To determine the neural substrates underlying visual memories, we investigated the neuronal representation of working memory content in the primary visual cortex of monkeys. Our study revealed that neurons exhibit unique responses to different memory contents, using firing patterns distinct from those observed during the perception of external visual stimuli. Moreover, this neuronal representation evolves with alterations in the recalled content and extends beyond the retinotopic areas typically reserved for processing external visual input. These discoveries shed light on the visual encoding of memories and indicate avenues for understanding the remarkable power of the mind's eye.

It takes two: A dyadic approach to the content and functions of vicarious memories.

It takes two: A dyadic approach to the content and functions of vicarious memories.

Shift happens: aging alters the content but not the organization of memory for complex events

ABSTRACT While cognitive aging research has compared episodic memory accuracy between younger and older adults, less work has described differences in how memories are encoded and recalled. This is important for memories of real-world experiences, since there is immense variability in which details can be accessed and organized into narratives. We investigated age effects on the organization and content of memory for complex events. In two independent samples (N = 45; 60), young and older adults encoded and recalled the same short-movie. We applied a novel scoring on the recollections to quantify recall accuracy, temporal organization (temporal contiguity, forward asymmetry), and content (perceptual, conceptual). No age-effects on recall accuracy nor on metrics of temporal organization emerged. Older adults provided more conceptual and non-episodic content, whereas younger adults reported a higher proportion of event-specific information. Our results indicate that age-related differences in episodic recall reflect distinctions in what details are assembled from the past.

Transient global amnesia - benign memory blackout

Transient global amnesia (TGA) is a typical clinical syndrome characterized by acute, predominantly anterograde amnesia. New epidemiological data assume a significantly higher annual incidence than previously assumed, namely around 15 cases per 100,000 people. Those affected, usually over the age of 50, cannot remember new memory content for longer than 30-180 seconds and therefore ask repetitive questions about current events. All other cognitive functions are unimpaired, and everything previously learnt, e.g. driving or cooking, can be carried out. The episodes are self-limiting and by definition subside within 24 hours. At least 10% of those affected will experience 1-5 recurrences in the future. The punctate lesions in the hippocampus, which are found on MRI in at least 50% of patients after 24-72 hours, are distributed 2/3 unilaterally and 1/3 bilaterally. Using 7 Tesla MRI the frequency of detected lesions increases to 90% compared to 50% with 1.5 or 3 Tesla. Beyond the punctiform hippocampal lesions, other memory-related network disorders, including the default network, are also suggested to be involved in the pathomechanism of TGA. TGA etiology and pathophysiology are not known in detail. Vascular, migraine-like, epilepsy-like, and psychogenic mechanisms are discussed. Triggers of the episodes are often physical exertion with a Valsalva character. Management is aimed at identifying the syndrome based on the typical clinical presentation and ruling out possible differential diagnoses with similar symptoms. During the TGA, the usually anxious relatives should be reassured of the benign and inconsequential nature of the episode.

Linking Cognitive Integrity to Working Memory Dynamics in the Aging Human Brain.

Aging is accompanied by a decline of working memory, an important cognitive capacity that involves stimulus-selective neural activity that persists after stimulus presentation. Here, we unraveled working memory dynamics in older human adults (male and female) including those diagnosed with mild cognitive impairment (MCI) using a combination of behavioral modeling, neuropsychological assessment, and MEG recordings of brain activity. Younger adults (male and female) were studied with behavioral modeling only. Participants performed a visuospatial delayed match-to-sample task under systematic manipulation of the delay and distance between sample and test stimuli. Their behavior (match/nonmatch decisions) was fit with a computational model permitting the dissociation of noise in the internal operations underlying the working memory performance from a strategic decision threshold. Task accuracy decreased with delay duration and sample/test proximity. When sample/test distances were small, older adults committed more false alarms than younger adults. The computational model explained the participants' behavior well. The model parameters reflecting internal noise (not decision threshold) correlated with the precision of stimulus-selective cortical activity measured with MEG during the delay interval. The model uncovered an increase specifically in working memory noise in older compared with younger participants. Furthermore, in the MCI group, but not in the older healthy controls, internal noise correlated with the participants' clinically assessed cognitive integrity. Our results are consistent with the idea that the stability of working memory contents deteriorates in aging, in a manner that is specifically linked to the overall cognitive integrity of individuals diagnosed with MCI.

Jointly looking to the past and the future in visual working memory

Working memory enables us to bridge past sensory information to upcoming future behaviour. Accordingly, by its very nature, working memory is concerned with two components: the past and the future. Yet, in conventional laboratory tasks, these two components are often conflated, such as when sensory information in working memory is encoded and tested at the same location. We developed a task in which we dissociated the past (encoded location) and future (to-be-tested location) attributes of visual contents in working memory. This enabled us to independently track the utilisation of past and future memory attributes through gaze, as observed during mnemonic selection. Our results reveal the joint consideration of past and future locations. This was prevalent even at the single-trial level of individual saccades that were jointly biased to the past and future. This uncovers the rich nature of working memory representations, whereby both past and future memory attributes are retained and can be accessed together when memory contents become relevant for behaviour.

Jointly looking to the past and the future in visual working memory.

Working memory enables us to bridge past sensory information to upcoming future behaviour. Accordingly, by its very nature, working memory is concerned with two components: the past and the future. Yet, in conventional laboratory tasks, these two components are often conflated, such as when sensory information in working memory is encoded and tested at the same location. We developed a task in which we dissociated the past (encoded location) and future (to-be-tested location) attributes of visual contents in working memory. This enabled us to independently track the utilisation of past and future memory attributes through gaze, as observed during mnemonic selection. Our results reveal the joint consideration of past and future locations. This was prevalent even at the single-trial level of individual saccades that were jointly biased to the past and future. This uncovers the rich nature of working memory representations, whereby both past and future memory attributes are retained and can be accessed together when memory contents become relevant for behaviour.

Prospects for epistemic generationism about memory

A source of epistemic justification can be either preservative or generative, in that it can either just preserve justification that was provided by some other source or generate justification on its own. This paper asks what is required for generationism about memory to be true and argues that there are rather demanding conditions that a case of memory justification needs to satisfy in order to count as epistemically generative in a substantive sense. By considering a parallel argument for epistemically generative cases of imagination and drawing from empirical data on event completion, we argue that there are such cases of memory justification because the way in which memory processes fill in the content of event memories suggests that memory is fit to provide justification about past events that is not due to a source other than memory.

Streaming Algorithms with Few State Changes

In this paper, we study streaming algorithms that minimize the number of changes made to their internal state (i.e., memory contents). While the design of streaming algorithms typically focuses on minimizing space and update time, these metrics fail to capture the asymmetric costs, inherent in modern hardware and database systems, of reading versus writing to memory. In fact, most streaming algorithms write to their memory on every update, which is undesirable when writing is significantly more expensive than reading. This raises the question of whether streaming algorithms with small space and number of memory writes are possible. We first demonstrate that, for the fundamental F p moment estimation problem with p ≥ 1, any streaming algorithm that achieves a constant factor approximation must make Ω(n 1-1/p ) internal state changes, regardless of how much space it uses. Perhaps surprisingly, we show that this lower bound can be matched by an algorithm which also has near-optimal space complexity. Specifically, we give a (1+ε)-approximation algorithm for F p moment estimation that use a near-optimal ~O ε (n 1-1/p ) number of state changes, while simultaneously achieving near-optimal space, i.e., for p∈[1,2), our algorithm uses poly(log n,1/ε) bits of space for, while for p>2, the algorithm uses ~O ε (n 1-1/p ) space. We similarly design streaming algorithms that are simultaneously near-optimal in both space complexity and the number of state changes for the heavy-hitters problem, sparse support recovery, and entropy estimation. Our results demonstrate that an optimal number of state changes can be achieved without sacrificing space complexity.

Memory, mood and associated neuroanatomy in individuals with steroid sulphatase deficiency (X-linked ichthyosis).

Steroid sulphatase (STS) cleaves sulphate groups from steroid hormones, and steroid (sulphate) levels correlate with mood and age-related cognitive decline. In animals, STS inhibition or deletion of the associated gene, enhances memory/neuroprotection and alters hippocampal neurochemistry. Little is known about the consequences of constitutive STS deficiency on memory-related processes in humans. We investigated self-reported memory performance (Multifactorial Memory Questionnaire), word-picture recall and recent mood (Kessler Psychological Distress Scale, K10) in adult males with STS deficiency diagnosed with the dermatological condition X-linked ichthyosis (XLI; n = 41) and in adult female carriers of XLI-associated genetic variants (n = 79); we compared results to those obtained from matched control subjects [diagnosed with ichthyosis vulgaris (IV, n = 98) or recruited from the general population (n = 250)]. Using the UK Biobank, we compared mood/memory-related neuroanatomy in carriers of genetic deletions encompassing STS (n = 28) and non-carriers (n = 34,522). We found poorer word-picture recall and lower perceived memory abilities in males with XLI and female carriers compared with control groups. XLI-associated variant carriers and individuals with IV reported more adverse mood symptoms, reduced memory contentment and greater use of memory aids, compared with general population controls. Mood and memory findings appeared largely independent. Neuroanatomical analysis only indicated a nominally-significantly larger molecular layer in the right hippocampal body of deletion carriers relative to non-carriers. In humans, constitutive STS deficiency appears associated with mood-independent impairments in memory but not with large effects on underlying brain structure; the mediating psychobiological mechanisms might be explored further in individuals with XLI and in new mammalian models lacking STS developmentally.

Divergent roles of early visual cortex and inferior frontal junction in visual working memory

BackgroundRecent studies indicate that both prefrontal and visual regions play critical roles in visual working memory (VWM), with prefrontal regions mainly associated with executive functions, and visual cortices linked to representations of memory contents. VWM involves the selective filtering of irrelevant information, yet the specific contributions of the prefrontal regions and visual cortex in this process remain unclear. ObjectiveTo understand the dynamic causal roles of prefrontal and visual regions in VWM. MethodsThe differentiation of VWM components was achieved using a computational model that incorporated a swap rate for non-target stimuli. Single-pulse magnetic transcranial stimulation (spTMS) was delivered to the early visual cortex (EVC) and the inferior frontal junction (IFJ) across different phases of an orientation recall task that with or without distractors. ResultsOur results indicate that spTMS over the EVC and IFJ influences VWM particularly when distractors are present. VWM precision can be impacted by spTMS applied to either region during the early retention, while spTMS effect is especially prominent when EVC is stimulated during the late retention phase and when directed at the ipsilateral EVC. Conversely, the probability of accurately recalling the target exhibited comparable patterns when spTMS was administered to either the EVC or IFJ. ConclusionsWe highlight the “sensory recruitment” of VWM characterized by critical involvement of EVC particularly in the information-filtering process within VWM. The maintenance of memory content representations necessitates ongoing communication between the EVC and IFJ throughout the entirety of the VWM process in a dynamic pattern.

The Relationship Between Subjective Memory Experience and Objective Memory Performance Remains Stable Across the Lifespan

The way humans remember events changes across the lifespan. Older adults often rate the vividness of their memories as being greater or equal to younger adults, despite poorer performance on episodic memory tasks. This study explored how the content (place, person and object) and specificity (conceptual gist versus perceptual detail) of event memories relate to the subjective experience of memory vividness and memory confidence, and how this relationship is affected by healthy ageing. 100 healthy older adults and 100 young adults were tested online, using an adapted version of a paradigm developed by Cooper and Ritchey (2022). At encoding, participants generated a distinctive story to associate together (1) a theme word, and images of (2) a famous person, (3) a place, and (4) an object, to create unique events. At test, participants identified the event components using word labels (indexing conceptual gist), and the studied images (indexing perceptual details). Replicating Cooper and Ritchey (2022), we found that young adults’ memory vividness ratings were related to their memory for the conceptual gist of the events, with no modulation by the type of the content recalled. Strikingly, older adults showed the same relationship between vividness measures and objective performance as the young adults. Contrary to some previous studies, we found that older adults obtained lower scores for gist-based memory, and their vividness ratings were correspondingly lower than the younger adults. Across both age groups, vividness and confidence ratings followed a similar pattern, showing a stronger relationship with conceptual gist. Our results suggest that throughout the lifespan, the amount of conceptual information retrieved about an event relates to the ability to reexperience it vividly, and to have confidence in one’s memory.

Probing the content of affective semantic memory following caregiving-related early adversity.

Cognitive science has demonstrated that we construct knowledge about the world by abstracting patterns from routinely encountered experiences and storing them as semantic memories. This preregistered study tested the hypothesis that caregiving-related early adversities (crEAs) shape affective semantic memories to reflect the content of those adverse interpersonal-affective experiences. We also tested the hypothesis that because affective semantic memories may continue to evolve in response to later-occurring positive experiences, child-perceived attachment security will inform their content. The sample comprised 160 children (ages 6-12 at Visit 1; 87F/73M), 66% of whom experienced crEAs (n=105). At Visit 1, crEA exposure prior to study enrollment was operationalized as parental-reports endorsing a history of crEAs (abuse/neglect, permanent/significant parent-child separation); while child-reports assessed concurrent attachment security. A false memory task was administered online ∼2.5 years later (Visit 2) to probe the content of affective semantic memories-specifically attachment schemas. Results showed that crEA exposure (vs. no exposure) was associated with a higher likelihood of falsely endorsing insecure (vs. secure) schema scenes. Attachment security moderated the association between crEA exposure and insecure schema-based false recognition. Findings suggest that interpersonal-affective semantic schemas include representations of parent-child interactions that may capture the quality of one's own attachment experiences and that these representations shape how children remember attachment-relevant narrative events. Findings are also consistent with the hypothesis that these affective semantic memories can be modified by later experiences. Moving forward, the approach taken in this study provides a means of operationalizing Bowlby's notion of internal working models within a cognitive neuroscience framework. RESEARCH HIGHLIGHTS: Affective semantic memories representing insecure schema knowledge (child needs + needs-not-met) may be more salient, elaborated, and persistent among youths exposed to early caregiving adversity. All youths, irrespective of early caregiving adversity exposure, may possess affective semantic memories that represent knowledge of secure schemas (child needs + needs-met). Establishing secure relationships with parents following early-occurring caregiving adversity may attenuate the expression of insecure semantic memories, suggesting potential malleability. Affective semantic memories include schema representations of parent-child interactions that may capture the quality of one's own attachment experiences and shape how youths remember attachment-relevant events.

Unifying network model links recency and central tendency biases in working memory

The central tendency bias, or contraction bias, is a phenomenon where the judgment of the magnitude of items held in working memory appears to be biased toward the average of past observations. It is assumed to be an optimal strategy by the brain and commonly thought of as an expression of the brain’s ability to learn the statistical structure of sensory input. On the other hand, recency biases such as serial dependence are also commonly observed and are thought to reflect the content of working memory. Recent results from an auditory delayed comparison task in rats suggest that both biases may be more related than previously thought: when the posterior parietal cortex (PPC) was silenced, both short-term and contraction biases were reduced. By proposing a model of the circuit that may be involved in generating the behavior, we show that a volatile working memory content susceptible to shifting to the past sensory experience – producing short-term sensory history biases – naturally leads to contraction bias. The errors, occurring at the level of individual trials, are sampled from the full distribution of the stimuli and are not due to a gradual shift of the memory toward the sensory distribution’s mean. Our results are consistent with a broad set of behavioral findings and provide predictions of performance across different stimulus distributions and timings, delay intervals, as well as neuronal dynamics in putative working memory areas. Finally, we validate our model by performing a set of human psychophysics experiments of an auditory parametric working memory task.

Unifying network model links recency and central tendency biases in working memory.

The central tendency bias, or contraction bias, is a phenomenon where the judgment of the magnitude of items held in working memory appears to be biased toward the average of past observations. It is assumed to be an optimal strategy by the brain and commonly thought of as an expression of the brain's ability to learn the statistical structure of sensory input. On the other hand, recency biases such as serial dependence are also commonly observed and are thought to reflect the content of working memory. Recent results from an auditory delayed comparison task in rats suggest that both biases may be more related than previously thought: when the posterior parietal cortex (PPC) was silenced, both short-term and contraction biases were reduced. By proposing a model of the circuit that may be involved in generating the behavior, we show that a volatile working memory content susceptible to shifting to the past sensory experience - producing short-term sensory history biases - naturally leads to contraction bias. The errors, occurring at the level of individual trials, are sampled from the full distribution of the stimuli and are not due to a gradual shift of the memory toward the sensory distribution's mean. Our results are consistent with a broad set of behavioral findings and provide predictions of performance across different stimulus distributions and timings, delay intervals, as well as neuronal dynamics in putative working memory areas. Finally, we validate our model by performing a set of human psychophysics experiments of an auditory parametric working memory task.

Control of working memory by phase–amplitude coupling of human hippocampal neurons

Retaining information in working memory is a demanding process that relies on cognitive control to protect memoranda-specific persistent activity from interference1,2. However, how cognitive control regulates working memory storage is unclear. Here we show that interactions of frontal control and hippocampal persistent activity are coordinated by theta–gamma phase–amplitude coupling (TG-PAC). We recorded single neurons in the human medial temporal and frontal lobe while patients maintained multiple items in their working memory. In the hippocampus, TG-PAC was indicative of working memory load and quality. We identified cells that selectively spiked during nonlinear interactions of theta phase and gamma amplitude. The spike timing of these PAC neurons was coordinated with frontal theta activity when cognitive control demand was high. By introducing noise correlations with persistently active neurons in the hippocampus, PAC neurons shaped the geometry of the population code. This led to higher-fidelity representations of working memory content that were associated with improved behaviour. Our results support a multicomponent architecture of working memory1,2, with frontal control managing maintenance of working memory content in storage-related areas3–5. Within this framework, hippocampal TG-PAC integrates cognitive control and working memory storage across brain areas, thereby suggesting a potential mechanism for top-down control over sensory-driven processes.

Differential effects of high-definition transcranial direct current stimulation (HD-tDCS) on attentional guidance by working memory in males with substance use disorder according to memory modality

Information stored in working memory can guide perception selection, and this process is modulated by cognitive control. Although previous studies have demonstrated that neurostimulation over the left dorsolateral prefrontal cortex (lDLPFC) contributes to restore cognitive control among individuals with substance use disorder (SUD), there remains an open question about the potential stimulation effects on memory-driven attention. To address this issue, the present study adopted a combined working memory/attention paradigm while employing high-definition transcranial direct current stimulation (HD-tDCS) to stimulate the lDLPFC. Observers were asked to maintain visual or audiovisual information in memory while executing a search task, while the validity of the memory contents for the subsequent search task could be either invalid or neutral. The results showed a faint memory-driven attentional suppression effect in sham stimulation only under the audiovisual condition. Moreover, anodal HD-tDCS facilitated attentional suppression effect in both the strength and temporal dynamics under the visual-only condition, whereas the effect was impaired or unchanged under the audiovisual condition. Surprisingly, cathodal HD-tDCS selectively improved temporal dynamics of the attentional suppression effect under the audiovisual condition. The present study revealed the differential enhancement of HD-tDCS on cognitive control over visual and audiovisual memory-driven attention among individuals with SUD.

Sfântul Augustin despre memoria lucrurilor și memoria spirituală

Augustine is fascinated by the domains that memory dominates, as well as by the mystery that envelops them. Their classification cannot lead to the inclusion of what it represents in the soul, but you can be surprised by the faculties that it can coordinate or stimulate in one way or another. More precisely, it surprises you to discover contents in your memory that we believe come from outside, from an objective reality that our senses probe and offer us. From the life of consciousness ‒ which, at every investigation, meets us as a mystery, which constitutes the originality of Augustine's thinking ‒ memory is also a part, but not only it is lived in this way, but also time, like any faculty or aspect over which consciousness falls in its movement of self-absorption.