Recent Memory Research Articles

Content-specific vulnerability of recent episodic memories in Alzheimer's disease

Endel Tulving's episodic memory framework emphasizes the multifaceted re-experiencing of personal events. Indeed, decades of research focused on the experiential nature of episodic memories, usually treating recent episodic memory as a coherent experiential quality. However, recent insights into the functional architecture of the medial temporal lobe show that different types of mnemonic information are segregated into distinct neural pathways in brain circuits empirically associated with episodic memory. Moreover, recent memories do not fade as a whole under conditions of progressive neurodegeneration in these brain circuits, notably in Alzheimer's disease. Instead, certain memory content seem particularly vulnerable from the moment of their encoding while other content can remain memorable consistently across individuals and contexts. We propose that these observations are related to the content-specific functional architecture of the medial temporal lobe and consequently to a content-specific impairment of memory at different stages of the neurodegeneration. To develop Endel Tulving's inspirational legacy further and to advance our understanding of how memory function is affected by neurodegenerative conditions such as Alzheimer's disease, we postulate that it is compelling to focus on the representational content of recent episodic memories.

Forecasting crude oil price volatility out-of-sample using news-based geopolitical risk index: What forms of nonlinearity help improve forecast accuracy the most?

We evaluate the degree to which the geopolitical risk (GPR) index suggested in Caldara and Iacoviello (2018) helps improve the accuracy of one-month ahead out-of-sample point (density) forecasts of West Texas Intermediate (WTI) crude oil price log-realized volatility, and what forms of nonlinearity offer the largest degree of relative forecast accuracy gains. The central finding in this study is to demonstrate that contrary to what is perceived in the current literature, the form of nonlinearity that delivers the largest degree of point (density) forecast accuracy gains relative to the benchmark does not have to do with asymmetry (i.e. positive or negative GPR changes) or higher than average GPR increases, but rather GPR increases beyond the maximum GPR value over the last twelve months. In other words, GPR increases help deliver the highest degree of forecast accuracy gains relative to the benchmark if they exceed the maximum value in recent memory. However, GPR decreases below recent minimums do not help deliver relative accuracy gains.

Reading Mark’s Gospel as a Text From Collective Memory

Reading Mark’s Gospel as a Text From Collective Memory

Corticosterone differentially modulates time-dependent fear generalization following mild or moderate fear conditioning training in rats

Stressful and emotionally arousing experiences create strong memories that seem to lose specificity over time. It is uncertain, however, how the stress system contributes to the phenomenon of time-dependent fear generalization. Here, we investigated whether post-training corticosterone (CORT-HBC) injections, given after different training intensities, affect contextual fear memory specificity at several time points. We trained male Wistar rats on the contextual fear conditioning (CFC) task using two footshock intensities (mild CFC, 3 footshocks of 0.3 mA, or moderate CFC, 3x 0.6 mA) and immediately after the training session we administered CORT-HBC systemically. We first tested the animals in a novel context and then in the training context at different intervals following training (2, 14, 28 or 42 days). By measuring freezing in the novel context and then contrasting freezing times shown in both contexts, we inferred contextual fear generalization for each rat, classifying them into Generalizers or Discriminators. Following mild CFC training, the glucocorticoid injection promoted an accurate contextual memory at the recent time point (2 days), and increase the contextual memory accuracy 28 days after training. In contrast, after the moderate CFC training, CORT-HBC facilitated contextual generalization at 14 days, compared to the control group that maintained contextual discrimination at this timepoint. For this training intensity, however, CORT-HBC did not have any effect on recent memory specificity. These findings indicate that treatment with CORT-HBC immediately after the encoding of mild or moderately arousing experiences may differentially modulate memory consolidation and time-dependent fear generalization.

Russia and peak-oil demand

Russia relies on oil income to fund its government budget and to manage its macroeconomic affairs. The decline of crude-oil prices in 2014–16 and in 2020 - the first due to oversupply and the second to a pandemic-related drop in demand - was a painful reminder of this fact. It was also a preview of the moment in the future when global demand for oil will begin to permanently decline. It is unclear when this will occur, but when it does, it could threaten the political economy of the Russian government in a more comprehensive way than any prior economic or political challenge in recent memory.

COVID-19 Is Becoming A '9/11 Moment' For Borders And Health.

The COVID-19 pandemic has had a dramatic impact on the cross-border movement of people. As governments begin to reopen their borders and cautiously restart travel, their attention is shifting to border procedures that could facilitate travel while protecting the homeland from travelers who may be infected. This is not the first time in recent memory that border management has had to be rethought under the pressure of large external forces. This article examines parallels between the current situation and the early 2000s, when the September 11, 2001, attacks on US targets caused a seismic shift in managing borders. We find echoes of today's responses in the initial fragmentation and chaos of two decades ago, which eventually gave way to a coordinated international system. We also analyze the implications of the emerging border health infrastructure for other migration challenges-particularly addressing irregular crossings and the border "crises" they create. Because the aftershocks of the pandemic on all aspects of people on the move could be felt for decades, immigration, mobility management, and public health priorities must be considered alongside one another.

Flood Risk and River Conservation: Mapping Citizen Perception to Support Sustainable River Management

Involving citizens in river and flood risk management is critical for risk reduction and sustainable development within river basins, but local community input is often limited. This is partly due to the difficulty of quantifying the perceived values and risks related to the rivers, because these are based on personal knowledge and opinions. There is a need for more data on locals’ opinions and how they are spatially distributed across the river basin. Studies analyzing how perceived risks match evidence-based data can be a first step to including local knowledge in the decision-making process and pose the basis to enhance preparedness. Here, we present a blueprint questionnaire to characterize the perception of flood risk and its spatial distribution across the river basin. Respondents are asked their perception of the role of the river in terms of flood risk and management, as well as to pinpoint on a map the areas they identify as the most dangerous during floods. The approach is tested on the Tagliamento River in the Italian Alps, characterized by debates regarding flood protection, flood management and ecological conservation. The flood risk perception map shows good agreement between perceived risk and existing flood risk assessment maps in the lower basin, where major floods happened in recent memory (1966). In the upper basin, despite having suffered frequent floods, participants are more uncertain about the risks. There is interest in being involved in the risk management debate, and most respondents believe that risk reduction and river conservation are compatible. Land use planning is identified as a factor that can increase flood risk. The results point to the necessity to tackle together conservation, risk management and land use planning in order to develop risk-oriented river management strategies. Our study demonstrates how online participatory mapping can be used to improve the understanding of citizens’ perceptions and expectations with regards to their river, and support participation in sustainable river management.

Expression of IGF-2 Receptor in the Auditory Cortex Improves the Precision of Recent Fear Memories and Maintains Detailed Remote Fear Memories Over Time.

Traumatic memories may become less precise over time and lead to the development of fear responses to novel stimuli, a process referred to as time-dependent fear generalization. The conditions that cause the growth of fear generalization over time are poorly understood. Here, we found that, in male rats, the level of discrimination at the early time point contributes to determining whether fear generalization will develop with the passage of time or not, suggesting a link between the precision of recent memory and the stability of remote engrams. We also found that the expression of insulin-like growth factor 2 receptor in layer 2/3 of the auditory cortex is linked to the precision of recent memories and to the stability of remote engrams and the development of fear generalization over time. These findings provide new insights on the neural mechanisms that underlie the time-dependent development of fear generalization that may occur over time after a traumatic event.

Diversity in Serine/Threonine Protein Kinase-4 Deficiency and Review of the Literature

Serine/threonine kinase-4 (STK4) deficiency is an autosomal recessive combined immunodeficiency. We aimed to define characteristic clinical and laboratory features to aid the differential diagnosis and determine the most suitable therapy. In addition to nine STK4 deficiency patients, we reviewed 15 patients from the medical literature. We compared B lymphocyte subgroups of the cohort with age-matched healthy controls. In the cohort, median age at symptom onset and age at diagnosis were 6 years 8 months (range, 6-248 months) and 7 years 5 months (range, 6-260 months), respectively. The main clinical findings were infections (in all nine patients [9 of 9]), autoimmune or inflammatory diseases (7 of 9), and atopy (4 of 9). CD4 lymphopenia (9 out 9), lymphopenia (7 out 9), intermittent eosinophilia (4 out 9), transient neutropenia (3 out 9), low IgM (4 out 9), and high IgE (4 out 9) were common. Decreased recent thymic emigrants, naive and central memory T cells, but increased effector memory T cells were present. The increase in plasmablasts (P= .003) and decrease in switched memory B cells (P= .022) were significant. When 24 patients are analyzed, cutaneous viral infections (n= 20), recurrent pneumonia (n= 18), Epstein Barr virus-associated lymphoproliferation (n= 11), atopic dermatitis (n= 10), autoimmune cytopenia (n= 7), and lymphoma (n= 6) were frequent. Lymphopenia, CD4 lymphopenia, high IgG, IgA, and IgE were common laboratory characteristics. The differential diagnosis with autosomal recessive hyper-IgE syndrome is crucial. Because, atopy and CD4 lymphopenia are common in both diseases. Immunoglobulins, antibacterial, and antiviral prophylaxis are the mainstays of treatment. Clinicians may use immunomodulatory therapies during inflammatory or autoimmune complications. However, more data are needed to recommend hematopoietic stem cell transplantation as a safe therapy.

How can automated linguistic analysis help to discern functional cognitive disorder from healthy controls and mild cognitive impairment?

AimsThe disease burden of cognitive impairment is significant and increasing. The aetiology of cognitive impairment can be structural, such as in mild cognitive impairment (MCI) due to early Alzheimer's disease (AD), or in functional cognitive disorder (FCD), where there is no structural pathology. Many people with FCD receive a delayed diagnosis following invasive or costly investigations. Accurate, timely diagnosis improves outcomes across all patients with cognitive impairment. Research suggests that analysis of linguistic features of speech may provide a non-invasive diagnostic tool. This study aimed to investigate the linguistic differences in conversations between people with early signs of cognitive impairment with and without structural pathology, with a view to developing a screening tool using linguistic analysis of conversations.MethodIn this explorative, cross-sectional study, we recruited 25 people with MCI considered likely due to AD, (diagnosed according to Petersen's criteria and referred to as PwMCI), 25 healthy controls (HCs) and 15 people with FCD (PwFCD). Participants’ responses to a standard questionnaire asked by an interactional virtual agent (Digital Doctor) were quantified using previously identified parameters. This paper presents statistical analyses of the responses and a discussion of the results.ResultPwMCI produced fewer words than PwFCD and HCs. The ratio of pauses to speech was generally lower for PwMCI and PwFCD than for HCs. PwMCI showed a greater pause to speech ratio for recent questions (such as ‘what did you do at the weekend?’) compared with the HCs. Those with FCD showed the greatest pause to speech ratio in remote memory questions (such as ‘what was your first job?’). The average age of acquisition of answers for verbal fluency questions was lower in the MCI group than HCs.ConclusionThe results and qualitative observations support the relative preservation of remote memory compared to recent memory in MCI due to AD and decreased spontaneous elaboration in MCI compared with healthy controls and patients with FCD. Word count, age of acquisition and pause to speech ratio could form part of a diagnostic toolkit in identifying those with structural and functional causes of cognitive impairment. Further investigation is required using a large sample.

Longitudinal study of primary progressive aphasia in a patient with pathologically diagnosed Alzheimer\u2019s disease: a case report

BackgroundAlzheimer’s disease is a neurodegenerative disease involving the deposition of pathologic amyloid-β and tau protein in the cerebral cortex. Alzheimer’s disease is commonly characterized by progressive impairment of recent memory. Primary progressive aphasia is also often observed in patients with Alzheimer’s disease. Moreover, language-associated symptoms, such as primary progressive aphasia, are diverse and varied in Alzheimer’s disease. However, nonfluent/agrammatic variant primary progressive aphasia is not generally considered a symptom of Alzheimer’s disease. To date, there has been no longitudinal study of primary progressive aphasia in Japanese-speaking patients or in patients speaking other languages with pathologically diagnosed Alzheimer’s disease. Here we present a longitudinal study of primary progressive aphasia in a Japanese patient pathologically diagnosed with Alzheimer’s disease.Case presentationA 75-year-old Japanese man, whose wife reported that his memory was impaired, also suffered from suspected aphasia. He was pathologically diagnosed with Alzheimer’s disease using 11C-Pittsburgh compound-B positron emission tomography and 18F-THK5351 positron emission tomography. Based on clinical observation and the results of the Japanese standard language test of aphasia, he was also diagnosed with nonfluent/agrammatic variant primary progressive aphasia. During the subsequent 2 years, his cognitive impairment, aphasia, and behavioral and psychological symptoms of dementia progressed. Furthermore, progression of pathologic amyloid-β and tau protein deposition was revealed through 11C-Pittsburgh compound-B positron emission tomography and 18F-THK5351 positron emission tomography. Although the results of [123I] iodoamphetamine single-photon emission computed tomography suggested corticobasal degeneration, this was not observed on the [123I] FP-CIT single-photon emission computed tomography (SPECT) (DaTscan). A previous study had reported that Alzheimer’s disease with a nonfluent/agrammatic variant primary progressive aphasia was accompanied by corticobasal degeneration; however, this was not true in our case.ConclusionsThis is possibly the first longitudinal study of nonfluent/agrammatic variant primary progressive aphasia in a Japanese-speaking patient with pathologically diagnosed Alzheimer’s disease, but without corticobasal degeneration.

Associations of subjective cognitive and memory decline with depression, anxiety, and two-year change in objectively-assessed global cognition and memory

ABSTRACT Research studies exploring the association of cognitive complaints with objectively assessed cognitive decline report inconsistent results. However, many of these have methodological limitations. We investigated whether 1) more severe subjective cognitive decline (SCD) and subjective memory decline (SMD) predict change in objectively assessed global cognition, remote memory, recent memory, learning; 2) the predictive value of more severe SMD over change in objectively assessed remote memory, recent memory, and learning is stronger for individuals that report an SMD that started within the past five years than for those that report an SMD that started five or more years previously and/or stronger for those that experienced SMD within the past two years than for those who had not; and 3) greater depression and anxiety are associated with more severe SCD and SMD. We used two-year longitudinal data from the CFAS-Wales study (N = 1,531; mean (SD) age = 73.0 (6.0) years). We fitted linear regression models. More severe SCD and SMD did not predict change in objectively assessed global cognition, remote memory, and recent memory but predicted lower scores in learning. The prediction of SMD over change in learning was not stronger when individuals reported an SMD that started within the past five years compared to when they reported an SMD that started five or more years previously nor when individuals reported an SMD that started within the past two years than those who did not. Greater depression and anxiety were associated with more severe SCD and SMD. More severe SMD may be useful for predicting lower learning ability and for identifying individuals experiencing depression and anxiety.

Frailty is Associated With Frontal Cortex-Related Cognitive Function in Patients With Alzheimer Disease

We compared the cognitive functions of Alzheimer disease (AD) patients who were robust, frail or pre-frail and hypothesized that declines in frontal cortex-related neuropsychological function would be associated with frailty. One hundred and sixty outpatients aged 65 years or older with mild AD were enrolled. Cognitive function was assessed using the Cognitive Ability Screening Instrument and further classified into 4 clusters (recent memory, frontal cortex cluster, posterior cortex cluster, and orientation). Other variables included depressive mood, daily activities, body mass index, handgrip strength (HGS), and normal gait speed (NGS). Performance in daily activities, and slower NGS than robust group. Both the frail and pre-frail groups had lower HGS and more depressive symptoms than robust group. Generalized linear with ordinal logistic analysis showed that increment in age, slowing in NGS, and worse frontal cortex cluster function associated with being in a higher level of frailty. The patients with depression symptoms were the odds of being in a higher level of frailty compared to those without depression symptoms. In addition to physical and psychological symptoms, frailty is associated with specific cognitive domains in patients with AD. A multidimensional approach should be used to assess the impact of intervention programs focusing on frail patients with AD.

Ecotoxicology of alpine streams in the West Carpathians-Alpine Bullhead (Cottus poecilopus) and high mountain flash flood effects.

Flash floods represent a serious threat to wildlife, water biota, and human life in pre-alpine regions, particularly in recent historical memory. The alpine bullhead is an established bioindicator of water quality in mountain streams, which can be adversely affected by an increased propensity for flash flooding. The aim of this study was to examine the effect of flash flooding on the variation of chemical elements found in the skull of alpine bullheads, with a focus on inter-annual effects. Their bone tissue reflects an increased concentration of K and Cl and a decreased concentration of biogenic Cr, Zn, and Mo, absorbed mainly through the gills, for up to 2 years following a flood. During autumn, following a summer flash flood, the amount of Mn and Fe present in skull tissues of fish was found to have increased, tapering off again over the following year. These metals are predominantly ingested by bullheads while feeding. The lack of specific types of biogenic concentration in the water may be critical to the definition of presence/absence patterns, as populations were shown to decline 2 to 3 years post-flood. Pre-alpine streams are particularly susceptible to this type of flooding. The decreases in biogenic elements and increase of K and Cl exhibited in bullhead tissues indicate that a negative ecological footprint due to flash floods can still be observed several years following the event.

Memorials to John Snow - Pioneer in anaesthesia and epidemiology.

John Snow was an English physician and a founding father of epidemiology, whose name is inextricably linked with tracing the source of the 1854 cholera outbreak in Soho, which killed over 600 people. Despite his recommendation to remove the water pump handle and thus reduce the spread of cholera, his theory of faecal-oral transmission was not widely believed until after his death. Furthermore, he also pioneered substantial achievements in the development of anaesthesia. He studied both chloroform and ether, improving the accuracy of their delivery. In his obstetric practice, he achieved the feat of obtaining satisfactory analgesia with a safer technique and is remembered for administering chloroform to Queen Victoria, during the delivery of her last two children. There are several interesting and unusual memorials to Snow, ranging from replica water pumps, blue plaques and a public house named after him. The most recent new memorial was erected in 2017, in his home town of York, which commemorates his origins and his subsequent contribution to curbing the cholera outbreak. All the memorials commemorate his achievements, which remain relevant today. Public health and epidemiology expertise is required in the current world of the COVID-19 pandemic, where his legacy remains as important as ever.

Who Remembers Better? Sex Differences in Memory Among Higher Education Students in Nepal

There are manifestations that conclude sex plays a role in the memory function and thus sex tends to favour a memory type. This comparative study was conducted with higher education boy and girl students to assess the difference in different types of memory between sexes. The assessment done was based on Post Graduate Institute (PGI) memory scale developed by Pershad and Wig (1988). Sex was sole independent variable and dependent variables were ten memory subscales. Data collected were analysed by computing the mean and t-test. Comparison between two groups indicates significant difference in five subscales i.e., remote memory, recent memory, mental balance, attention and concentration and retention of dissimilar pairs. Among five subscales except in recent memory male score has outperformed and the difference in the score was significant. As such computing mean also demonstrated higher mean average in male side. However, the difference in memory between male and female has been demonstrated to some extent though it has followed distinct pattern.

The Sync-Fire/deSync model: Modelling the reactivation of dynamic memories from cortical alpha oscillations

We propose a neural network model to explore how humans can learn and accurately retrieve temporal sequences, such as melodies, movies, or other dynamic content. We identify target memories by their neural oscillatory signatures, as shown in recent human episodic memory paradigms. Our model comprises three plausible components for the binding of temporal content, where each component imposes unique limitations on the encoding and representation of that content. A cortical component actively represents sequences through the disruption of an intrinsically generated alpha rhythm, where a desynchronisation marks information-rich operations as the literature predicts. A binding component converts each event into a discrete index, enabling repetitions through a sparse encoding of events. A timing component – consisting of an oscillatory “ticking clock” made up of hierarchical synfire chains – discretely indexes a moment in time. By encoding the absolute timing between discretised events, we show how one can use cortical desynchronisations to dynamically detect unique temporal signatures as they are reactivated in the brain. We validate this model by simulating a series of events where sequences are uniquely identifiable by analysing phasic information, as several recent EEG/MEG studies have shown. As such, we show how one can encode and retrieve complete episodic memories where the quality of such memories is modulated by the following: alpha gate keepers to content representation; binding limitations that induce a blink in temporal perception; and nested oscillations that provide preferential learning phases in order to temporally sequence events.

Sustainability of 5G Green Network toward D2D Communication with RF- Energy Techniques

As the world pushes toward the utilization of greener innovation and limits energy squander, energy productivity in the remote organization has gotten more basic than any other time in recent memory. The cutting edge network, for example, 5G, are being intended to improve energy productivity and accordingly establish a basic part of the exploration and network planning. The 5G Green era required to convey a wide scope of administrations that incorporates upgraded versatile broadband, gigantic machine-type correspondence and ultra-dependability, and low inertness. Presently various difficulties and open doors for the plan of modern client affiliation instruments. Thus, considerable examination endeavours are committed to client relationship issues in HetNets, massive MIMO, mmWave, and energy harvesting. The paper further discussed the new security highlights including various innovations applied to 5G Green Communication, such as heterogeneous networks, gadget to-gadget interchanges or D2D Communication, enormous different info numerous yield, programming characterized networks, and the Internet of Things(IoT).

Left Hippocampus to Anterior Cingulate Cortex Connectivity Correlates with Worse Recent Verbal Memory in Pornography Addicted Juveniles (2702)

Left Hippocampus to Anterior Cingulate Cortex Connectivity Correlates with Worse Recent Verbal Memory in Pornography Addicted Juveniles (2702)

Food memory test to evaluate memory function.

To evaluate cognitive function with ease at bedside, we developed a novel neurologic exam called the "food memory test (FMT)" and evaluated its validity for use in clinical practice. In this prospective study in a neurology clinic, we asked patients about what they had eaten for the soup and main dish at the last meal [FMT1] and the second-to-last meal [FMT2]. If they answered correctly for both the soup and main dish, they received a "pass" score. If they did not answer or chose the wrong food, they received a "fail" score. We also performed conventional cognitive function tests for comparison. A total of 27 patients was enrolled, and 12 (44.4%) passed the FMT1 test. FMT1 has a strong correlation with conventional memory function tests, including time-place orientation, three-word recall, the Seoul Verbal Learning Test, and the Rey Complex Figure Test . FMT1 was not correlated with a depression score or with frontal lobe function tests. FMT2 showed less significant correlation with conventional memory tests. These results suggest that FMT1 is a reliable bedside test to evaluate recent memory. Clinical application of FMT in daily clinical practice is warranted.