Memory Performance Research Articles

Examining Working Memory Training for Healthy Adults—A Second-Order Meta-Analysis

Background: Enhancing working memory performance in cognitively and physically healthy individuals is a popular area of research. The results from a large number of studies have now been summarized in multiple meta-analyses. In these reviews, various training methods have been examined, including mindfulness training, adaptive working memory training, physical activity training, and video game training, to examine whether working memory capacity can be improved. This report aggregated the results of these meta-analyses using second-order meta-analytic approaches to ascertain the extent to which working memory functioning can be enhanced in healthy adults. Methods: A total of six meta-analyses of randomized controlled trials that compared working memory interventions to a control group were included in the analyses. These studies were identified after systematically searching three electronic databases: APA PsycInfo, ERIC and Medline. Collectively, the meta-analyses investigated the effects of cognitive programs, mindfulness, video games and physical activity on working memory. Only meta-analyses undertaken with healthy adults aged between 18 and 55 years were included in the report. Results: The results revealed an average improvement in working memory across the included studies compared to the control groups. The findings indicated a small yet significant enhancement in working memory, with a standardized mean difference of 0.335 (95% CI [0.223; 0.447], p < .001). Further analysis tests for superiority effects between the different working memory training programs revealed no significant differences between intervention effect sizes. Conclusion: Based on the findings, it can be concluded that the working memory capacity of healthy adults can be improved through training. However, the effect size is small, so the utility of this type of training in real-life improvements in cognition may be minimal. The evidence does not indicate that one type of working memory training is superior to another.

Organic Optoelectronic Synaptic Transistor with Enhanced UV Light Response Based on Insulating Polymer-Assisted p-n Heterojunction.

Optoelectronic synaptic transistors possess the capability to simultaneously accomplish perception and process functions within a single device, thereby not only addressing the limitations of von Neumann architectures but also serving as a promising candidate for emulating neural vision systems. The extensive range of organic semiconductor materials offers a plethora of possibilities for device fabrication; however, the severe recombination of photogenerated carriers imposes limitations on the utilization of organic p-n bulk heterostructures in synaptic transistor construction. By incorporating an insulating polymer and implementing a p-n planar heterojunction architecture, the 30% PCBM@PAN-DPPDTT transistor was constructed using the PCBM/DPPDTT heterojunction and the PCBM@PAN photoresponsive charge trapping layer. Due to the effect of the photoresponsive charge trapping layer and interface traps, the device not only overcomes the shortcomings of p-n bulk heterojunction and exhibits typical synaptic properties but also demonstrates a significantly enhanced response to ultraviolet (UV) light, exhibiting nearly four times more excitatory postsynaptic current (ΔEPSC) compared to the device lacking PCBM. The transistor matrix was employed to simulate the image perception and memory functions of the human neural vision system. Furthermore, an artificial neural network with high recognition accuracy (∼95%) of handwritten numbers was constructed. This study proposes an additional approach for mitigating the issue of rapid recombination of photogenerated charge carriers in the construction of optoelectronic synaptic transistors by utilizing p-n heterojunction.

Rectified activity-dependent population plasticity implicates cortical adaptation for memory and cognitive functions.

Cortical network undergoes rewiring everyday due to learning and memory events. To investigate the trends of population adaptation in neocortex overtime, we record cellular activity of large-scale cortical populations in response to neutral environments and conditioned contexts and identify a general intrinsic cortical adaptation mechanism, naming rectified activity-dependent population plasticity (RAPP). Comparing each adjacent day, the previously activated neurons reduce activity, but remain with residual potentiation, and increase population variability in proportion to their activity during previous recall trials. RAPP predicts both the decay of context-induced activity patterns and the emergence of sparse memory traces. Simulation analysis reveal that the local inhibitory connections might account for the residual potentiation in RAPP. Intriguingly, introducing the RAPP phenomenon in the artificial neural network show promising improvement in small sample size pattern recognition tasks. Thus, RAPP represents a phenomenon of cortical adaptation, contributing to the emergence of long-lasting memory and high cognitive functions.

Asthma and Memory Function in Children.

Asthma is a chronic respiratory disease affecting approximately 5 million children in the US. Rodent models of asthma indicate memory deficits, but little is known about whether asthma alters children's memory development. To assess whether childhood asthma is associated with lower memory abilities in children. This cohort study used observational data from the Adolescent Brain Cognitive Development (ABCD) Study, a multisite longitudinal investigation that began enrollment in 2015. Approximately 11 800 children aged 9 to 10 years were enrolled at baseline with follow-up at 1 and 2 years. Participants were selected based on exposures described subsequently to determine longitudinal and cross-sectional associations between asthma and memory. Data were analyzed from Month year to Month year. Asthma was determined from parent reports. For the longitudinal analysis, children were selected if they had asthma at baseline and at the 2-year follow-up (earlier childhood onset), at the 2-year follow-up only (later childhood onset), or no history of asthma. For the cross-sectional analysis, children were selected if they had asthma at any time point, or no history of asthma. The comparison group of children with asthma history was matched on demographic and health covariates for each analysis. The primary outcome was episodic memory. Secondary outcomes included processing speed, inhibition and attention. Four hundred seventy-four children were included in the longitudinal analysis (earlier childhood onset: 135 children; mean [SD] age, 9.90 [0.63] years; 76 [56%] male; 53 [28%] Black, 29 [21%] Hispanic or Latino, and 91 [48%] White; later childhood onset: 102 children; mean [SD] age 9.88 [0.59] years; 54 [53%] female; 22 [17%] Black, 19 [19%] Hispanic or Latino, and 83 [63%] White; comparison: 237 children; mean [SD] age, 9.89 [0.59] years; 121 [51%] male; 47 [15%] Black, 48 [20%] Hispanic or Latino, and 194 [62%] White). Children with earlier onset of asthma exhibited lower rates of longitudinal memory improvements relative to the comparison group (β = -0.17; 95% CI, -0.28 to -0.05; P = .01). Two thousand sixty-two children were selected for the cross-sectional analysis (with asthma: 1031 children; mean [SD] age, 11.99 [0.66] years; 588 [57%] male; 360 [27%] Black, 186 [18%] Hispanic or Latino, and 719 [54%] White; without asthma: 1031 children; mean [SD] age 12.00 [0.66] years; 477 [54%] female; 273 [21%] Black, 242 [23%] Hispanic or Latino, and 782 [59%] White). Children with asthma (1031 children) showed lower scores on episodic memory (β = -0.09; 95% CI, -0.18 to -0.01; P = .04), processing speed (β = -0.13; 95% CI, -0.22 to -0.03; P = .01), and inhibition and attention (β = -0.11; 95% CI, -0.21 to -0.02; P = .02). In this cohort study, asthma was associated with memory difficulties in children, which may be more severe if asthma onset is earlier in childhood and may extend to executive function abilities.

NCMP-06. GENOTYPE AND SEX IMPACT MEMORY FUNCTION AFTER BRAIN IRRADIATION

Abstract PURPOSE/OBJECTIVE Cognitive changes are a serious complication that can occur after brain radiotherapy. There is a need to better understand which individuals are more susceptible to develop strategies to preserve their function. The apolipoprotein E type 4 allele (APOEe4) APOE4 is the most prevalent genetic risk factor for Alzheimer Disease. We hypothesized that APOE genotype influences memory function after a subtherapeutic dose of whole brain irradiation in male and female mice. MATERIALS/METHODS Age-matched adult female and male mice engineered with either human APOE3 or APOE4 gene knocked-in were randomized to no treatment or whole brain irradiation (0 Gy or 5 Gy x 2), then evaluated with longitudinal neurobehavioral tests of learning, memory, pain threshold and anxiety. We performed immunohistochemical analyses of mouse brain sections at 1 month and at 4 months post-radiation to quantify extracellular amyloid beta plaques and other neuropathologic hallmarks associated with neurodegeneration. RESULTS Neurobehavioral testing identified significant sex and genotype-dependent changes in memory and anxiety measures developing longitudinally after brain irradiation. At baseline (unirradiated), APOE4 mice (male and female) performed worse on multiple memory measures. However after irradiation, sex and genotype each independently impacted multiple neurobehavioral function tests and also interacted with each other to significantly influence the timing and magnitude of changes in memory function. ApoE4 significantly impacted the toxicity of radiation in a sex-dependent manner. Neuropathologic analyses including amyloid beta plaque deposition and ApoE levels are ongoing. CONCLUSIONS After brain irradiation of relatively moderate dose, neurobehavioral performance including memory are impacted in a genotype and sex-dependent manner and dynamically over time. In addition to suggesting important sex-dependent differences in memory vulnerability, these data point to new opportunities for personalizing care for patients receiving brain irradiation.

Regulation of Glass Transition Temperature in Thermo‐Responsive Epoxy Shape Memory Polymers: The Roles of Chemical Crosslinking Density and Chain Flexibility

ABSTRACTShape memory polymers (SMPs) are novel kinds of smart materials whose shape can be changed in external conditions such as heat stimulus. Due to their excellent structural versatility and high elastic strain, they have important applications in the field of biomaterials. Here, a series of amorphous shape memory polymer materials are prepared and their shape memory properties and glass transition temperature (Tg) are also investigated. A special kind of epoxy polymer, whose shape can be changed at around physiological temperature, is synthesized by regulating the crosslinking density and introducing flexible aliphatic epoxy chains. The shape memory function of this epoxy polymer is studied by deformation test. In addition, to explore their application in the field of biomedical materials, the biocompatibility of the materials are evaluated, including the effects on the erythrocyte hemolysis rate and cell activity. The experimental results show that this kind of epoxy polymer has good shape memory function and biocompatibility.

Connectome-based predictive modelling of ageing, overall cognitive functioning and memory performance.

Resting-state functional magnetic resonance imaging (rs-fMRI) and brain functional connectome (we use 'brain connectome' hereafter for simplicity) have advanced our understanding of the ageing brain and age-related changes in cognitive function. Previous studies have investigated the association among brain connectome and age, global cognition, and memory function separately. However, very few have predicted age, overall cognitive functioning and memory performance in a single study to better understand their complex relationship. In this cross-sectional study, we applied an exploratory, data-driven method to investigate the brain connectome markers that could predict ageing, overall cognitive functioning assessed as intelligence quotient (IQ, measured by Wechsler Memory Scale) and memory performance assessed as memory quotient (MQ, measured by Wechsler Memory Scale) in a carefully designed, multicentre, normal ageing cohort (n = 313). Our results showed that brain connectome could predict ageing and IQ, but the association with MQ was weak. We found that the connectivity with orbital frontal cortex was associated with both ageing and IQ. Mediation analysis further showed that the brain connectome mediated the relationship between age and overall cognitive functioning, suggesting a protective brain connectomic mechanism for maintaining normal cognitive functions during healthy ageing. This work may shed light on the potential neural correlates of healthy ageing, overall cognitive functioning and memory performance.

Modality Matters: Evidence for the Benefits of Speech-Based Adaptive Retrieval Practice in Learners with Dyslexia.

Retrieval practice-the process of actively calling information to mind rather than passively studying materials-has been proven to be a highly effective learning strategy. However, only recently, researchers have started to examine differences between learners in terms of the optimal conditions of retrieval practice in applied educational settings. In this study (N=118), we focus on learners with dyslexia. We compare their performance to the performance of typical learners in an adaptive retrieval practice task using both typing-based and speech-based response conditions. We find that typical learners outperform learners with dyslexia when they are asked to respond by typing, but that this difference disappears when learners respond by speech. Using a mathematical model to decompose response times, we demonstrate that this typing-specific disadvantage in learners with dyslexia is mainly a consequence of processing delays, rather than poorer memory performance. These findings contribute to a better understanding of the mechanisms underlying declarative learning in dyslexia, and they can be used to tailor educational technology toward the needs of neurodiverse learners.

Leisure-time physical activity, cardiorespiratory fitness, and cognitive decline in middle-aged and older adults - The ELSA-Brasil study

ObjectivesDementia is a fast-growing public health problem. This study examined the association of physical activity and estimated cardiorespiratory fitness (eCRF) with the risk of cognitive impairment. Study designMulticentric, prospective cohort study. MethodsWe analyzed 10,121 participants of the ELSA-Brasil study. We assessed leisure-time physical activity using the long version of the IPAQ questionnaire and defined moderate-to-vigorous physical activity (MVPA) per week. We applied a non-exercise prediction equation to estimate eCRF and classified participants as unfit (lowest tertile) and fit. Leisure-time MVPA and eCRF were measured at baseline and follow-up. Incident cognitive impairment was based on memory, language, and executive function assessed at baseline and follow-up. ResultsDuring a median of 8.1 (7.8–8.5) years of follow-up, we identified 396 (3.9 %) incident cases of cognitive impairment. There was an inverse, non-linear association between the incidence of cognitive impairment and both leisure time MVPA and eCRF. Low eCRF (IRR: 1.29; 95%CI: 1.02, 1.64) and low MVPA (IRR: 1.40; 1.09, 1.82) were independently associated with an increased incidence. Increasing 1 MET in eCRF from baseline to follow-up visit was associated with a lower incidence of cognitive impairment (IRR: 0.80; 95%CI: 0.71, 0.91), while a decrease of 13.7 min per day in leisure time MVPA is associated with an increased incidence (IRR: 1.16; 95%CI: 1.01, 1.33) of cognitive impairment. These associations remained statistically significant in adults under 65 but not in older adults. ConclusionLow eCRF and leisure time MVPA are strong and independent predictors of incident cognitive impairment especially in middle-aged adults.

Advancing Neuro-diagnostics through Virtual Reality (VR) Development of Immersive Tools for the Diagnosis of Neurodegenerative and Cognitive Disorders

This research aims to transform neurodiagnostic methodologies by employing Virtual Reality (VR) as an innovative tool for the early detection, diagnosis, and monitoring of neurodegenerative and cognitive disorders, particularly Alzheimer’s and Parkinson’s disease. The approach leverages VR-based, patient-centric simulations designed to assess cognitive and motor functions within realistic, immersive environments. By integrating machine learning algorithms, these simulations capture detailed motor and cognitive biomarkers, allowing for nuanced analysis and early identification of subtle neurodegenerative indicators. In clinical settings, the VR framework has proven to be a valuable diagnostic tool, offering enhanced engagement and precision over traditional methods. Key advancements include VR-based cognitive testing frameworks that simulate real-life tasks, significantly aiding in assessing memory, spatial orientation, and executive functions, and VR tools for motor function evaluation that incorporate tasks like gait analysis to detect early motor impairment linked to Parkinson's disease. Through interdisciplinary collaborations with neurologists, software engineers, and AI experts, we have clinically validated these VR tools and demonstrated their efficacy in various clinical trials against standard neuropsychological assessments. Ultimately, this research underscores the potential of VR and AI to contribute to a paradigm shift in the early diagnosis and intervention of neurodegenerative disorders.

Towards theoretically understanding how long-term memory semantics can support working memory performance.

Working memory is the system that supports the temporary storage and processing of information. It is generally agreed that working memory is a mental workspace, with a combination of resources operating together to maintain information in mind for potential use in thought and action. Theories typically acknowledge the contributions of long-term memory to this system. One particular aspect of long-term memory, namely semantic long-term memory, can effectively supplement or "boost" working memory performance. This may be a relatively automatic process via the semantic properties of the stimuli or more active via strategy development and implementation. However, the precise mechanisms require greater theoretical understanding. In this review of the literature, we critically discuss theoretical models of working memory and their proposed links with long-term memory. We also explore empirical research that contributes to our understanding of the ways in which semantics can support performance of both verbal and visuospatial working memory tasks, with a view to potential intervention development. This includes the possibility of training people with lower performance (e.g., older adults) to use semantics during working memory tasks. We conclude that semantics may offer an opportunity to maximise working memory performance. However, to realise this potential, more research is needed, particularly in the visuospatial domain.

Assessment of Vitamin B12 Efficacy on Cognitive Memory Function and Depressive Symptoms: A Systematic Review and Meta-Analysis

Assessment of Vitamin B12 Efficacy on Cognitive Memory Function and Depressive Symptoms: A Systematic Review and Meta-Analysis

Protective effects of a lactobacilli mixture against Alzheimer’s disease-like pathology triggered by Porphyromonas gingivalis

Porphyromonas gingivalis (P. gingivalis) is one of the pathogens involved in gingival inflammation, which may trigger neuroinflammatory diseases such as Alzheimer’s disease (AD). This study aimed to investigate the protective (preventive and treatment) effects of a lactobacilli mixture combining Lactobacillus reuteri PTCC1655, Lactobacillus brevis CD0817, Lacticaseibacillus rhamnosus PTCC1637, and Lactobacillus plantarum PTCC1058 against P. gingivalis-induced gingival inflammation and AD-like pathology in rats. These probiotic strains exhibited cognitive enhancement effects, but this study proposed to assess their activity in a mixture. To propose a probable mechanism for P. gingivalis cognitive impairments, the TEs balance were analyzed in hippocampus and cortex tissues. Animals were divided into five groups: the control, lactobacilli, P. gingivalis, lactobacilli + P. gingivalis (prevention), and P. gingivalis + lactobacilli group (treatment) groups. The behavioral and histopathological changes were compared among them. Finally, The Trace elements (TEs) levels in the hippocampus and cortex tissues were analyzed. The palatal tissue sections of the P. gingivalis infected rats showed moderate inflammation with dense infiltration of inflammatory cells, a limited area of tissue edema, and vascular congestion. Additionally, passive avoidance learning and spatial memory were impaired. Histopathological tests revealed the presence of Aβ-positive cells in the P. gingivalis group. While the Aβ-positive cells decreased in the treatment group, their formation was inhibited in the preventive group. Administration of a mixture of lactobacilli (orally) effectively mitigated the gingival inflammation, Aβ production, and improved learning and memory functions. Moreover, Zn, Cu, and Mn levels in the hippocampus were dramatically elevated by P. gingivalis infection, whereas lactobacilli mixture mitigated these disruptive effects. The lactobacilli mixture significantly prevented the disruptive effects of P. gingivalis on gingival and brain tissues in rats. Therefore, new formulated combination of lactobacilli may be a good candidate for inhibiting the P. gingivalis infection and its subsequent cognitive effects. The current study aimed to evaluate the effects of a lactobacilli mixture to manage the disruptive effects of P. gingivalis infection on memory.

The effect of fampridine on working memory: a randomized controlled trial based on a genome-guided repurposing approach.

Working memory (WM), a key component of cognitive functions, is often impaired in psychiatric disorders such as schizophrenia. Through a genome-guided drug repurposing approach, we identified fampridine, a potassium channel blocker used to improve walking in multiple sclerosis, as a candidate for modulating WM. In a subsequent double-blind, randomized, placebo-controlled, crossover trial in 43 healthy young adults (ClinicalTrials.gov, NCT04652557), we assessed fampridine's impact on WM (3-back d-prime, primary outcome) after 3.5 days of repeated administration (10 mg twice daily). Independently of baseline cognitive performance, no significant main effect was observed (Wilcoxon P = 0.87, r = 0.026). However, lower baseline performance was associated with higher working memory performance after repeated intake of fampridine compared to placebo (rs = -0.37, P = 0.014, n = 43). Additionally, repeated intake of fampridine lowered resting motor threshold (F(1,37) = 5.31, P = 0.027, R2β = 0.01), the non-behavioral secondary outcome, indicating increased cortical excitability linked to cognitive function. Fampridine's capacity to enhance WM in low-performing individuals and to increase brain excitability points to its potential value for treating WM deficits.

The Sexual Dimorphism of the Neuroimmune Response in the Brains of Taenia crassiceps-Infected Mice

Background: Helminth infections are associated with cognitive deficits, especially in school-age children. Deworming treatment in heavily infected children improves their short- and long-term memory recall. In mice, intraperitoneal helminth infection with Taenia crassiceps (T. crassiceps) shows sexual dimorphism in terms of the parasite load, immune response, hormone levels, and behavioral changes. We have previously shown poorer short-term memory performance and changes in the concentrations of cytokines and neurotransmitters in the hippocampus, which were replicated in this study. The molecular changes in other brain structures, such as those related to reproduction, are unknown. Methods: Male and female Balb/cAnN mice were chronically infected with T. crassiceps larvae. We determined the peritoneal parasite load and established the presence of cytokines and neurotransmitters in the hippocampus, olfactory bulb, and hypothalamus. Results: The parasite load was higher in female than male infected mice, as expected. In the hippocampus, the neurotransmitters norepinephrine and serotonin increased in males but decreased in females. In contrast, in the olfactory bulb and hypothalamus, the neurotransmitters assessed showed no statistical differences. The cytokine profiles were different in each brain structure. The TNF-α levels in the olfactory bulb and the IL-4 levels in the hippocampus of infected mice were dimorphic; IFN-γ was augmented in both male and female infected animals, although the increase was higher in infected males. Conclusions: The brain responds to peripheral infection with cytokine levels that vary from structure to structure. This could be a partial explanation for the dimorphic behavioral alterations associated with infection, it also demonstrates the synergic interaction between the immune, the endocrine, and the nervous systems.

Lateralization of memory function in temporal lobe epilepsy using scene memory fMRI.

Functional magnetic resonance imaging (fMRI) offers an alternative to the traditional Wada test for presurgical language and memory lateralization that carries almost no risk. However, fMRI lateralization of episodic memory remains challenging because the hippocampus, which is fundamental to episodic memory, is smaller, more prone to susceptibility artifact, and harder to functionally modulate than language regions. We previously showed that a complex scene memory task can lateralize memory function in the mesial temporal lobe. Using data acquired from N = 45 patients with temporal lobe epilepsy acquired with an improved stimulus paradigm and high-resolution fMRI, we now demonstrate that memory activation can be successfully lateralized within hippocampus proper. PLAIN LANGUAGE SUMMARY: Epilepsy surgery can improve seizure control in patients with temporal lobe epilepsy (TLE) that cannot be controlled with medications also, but ablation or removal of temporal lobe brain tissue can also cause cognitive deficits. Functional MRI (fMRI) can noninvasively map brain activation and perform well in lateralizing and localizing language function, but localizing and lateralizing memory function is more challenging. Building upon prior work using complex scene encoding to map memory function, we demonstrate that the use of high-resolution fMRI along with an optimized task paradigm allows memory activation to be detected within the hippocampus. Because the hippocampus is both a common site of TLE and a key region underlying memory, this approach is expected to contribute to presurgical evaluation of TLE.

USP15 as a Potential Therapeutic Target in Cerebral Ischemia: Modulation of Ferroptosis and Cognitive Dysfunction via the Nrf2/GPX4 Axis in Mice.

This study aimed to investigate the role of ubiquitin-specific peptidase 15 (USP15) in ischemic cognitive dysfunction using a mouse model and a cerebral ischemia (CI) cell model, its impact on ferroptosis and the underlying mechanisms. Oxygen-glucose deprivation/reoxygenation (OGD/ R)-induced HT-22 cells were used to establish the CI cell model, and mice induced with CI were used as the animal model for ischemic cognitive dysfunction. Cell damage was evaluated using Cell Counting Kit-8 (CCK-8), flow cytometry (FCM), immunoblotting, and immunofluorescence assays. Cognitive dysfunction in the CI mice was assessed through water maze experiments. Ferroptosis was examined with an iron detection kit and immunoblotting, oxidative stress was evaluated using 2',7'-dichlorofluorescin diacetate (DCF) and enzyme-linked immunosorbent assay (ELISA), and mechanistic experiments were performed via immunoblotting. USP15 knockdown alleviated OGD/ R-induced damage in HT-22 cells. In vivo, USP15 depletion mitigated brain injury in middle cerebral artery occlusion (MCAO) mice and improved learning and memory function. The absence of USP15 reduced oxidative stress in MCAO mice and attenuated ferroptosis by activating nuclear factor erythroid 2-related factor 2 (Nrf2). Mechanistic investigations confirmed that USP15 depletion ameliorated cognitive impairment and ferroptosis through the activation of the Nrf2/ GPX4 axis. USP15 is associated with ferroptosis and cognitive dysfunction in mice and could serve as a potential therapeutic target in CI.

Memory and motivation in language revitalization practice

AbstractThis article examines the relationship between collective memory and individual second‐language (L2) learning motivation as articulated in a qualitative research study with language revitalization practitioners. These practitioners learn and teach their languages and engage in other activities in order to bring Indigenous or ancestral languages into new use following a period of loss. In this study, 28 revitalization practitioners from eight language communities were interviewed about why they choose to learn their languages, what challenges they face, and what supports them in their practice. Interviews were first analyzed using inductive thematic analysis and were subsequently analyzed deductively to engage with research on the functions of autobiographical memory. Findings show how collective memories are made salient in the language revitalization experience, how individuals grapple with painful memories of what their communities and families endured as a result of colonization, and how these collective memories impact individual L2 motivation. These findings illustrate the importance of collective memory in theorizing L2 motivation in order to enhance understanding of context, dismantle overly individualistic interpretations of L2 motivation models, and open avenues for critically engaging with historical trauma and resistance.

Tetrahedral framework nucleic acids inhibit Aβ-mediated ferroptosis and ameliorate cognitive and synaptic impairments in Alzheimer’s disease

BackgroundFerroptosis represents a nonapoptotic type of programmed cell death induced by excessive intracellular iron accumulation. Ferroptosis is an essential driver of the pathogenesis of Alzheimer’s disease (AD). Tetrahedral framework nucleic acids (tFNAs) are a novel type of nanoparticle with superior antiapoptotic capacity and excellent biocompatibility. However, the effect of tFNAs on Aβ triggered ferroptosis, cognitive and synaptic impairments in AD remains unknown.MethodsN2a cells were treated with Aβ combined with/without tFNAs. Cell viability and levels of Fe2+, lipid peroxidation, MDA, LDH, and GSH were examined. RNA sequencing was applied to explore dysregulated ferroptosis related genes. Seven-month-old APP/PS1 mice were intranasally administrated with tFNAs for two weeks. Fluorescence imaging was used to detect the tFNAs distribution in the brain. Novel object recognition (NOR) test followed by Morris water maze (MWM) was used to test the learning and memory performance of mice. Golgi staining, Western blot, and immunofluorescence staining were used to examine synaptic plasticity.ResultstFNAs promoted cell viability and GSH levels, reduced the levels of Fe2+, lipid peroxidation, MDA, and LDH in N2a cells treated with Aβ. RNA sequencing revealed that tFNAs reversed the promotive effect of Aβ on ferroptosis driver Atf3 gene and suppressive effect on ferroptosis suppressors Rrm2 and Furin genes. Fluorescence imaging confirmed the brain infiltration of tFNAs. tFNAs rescued synaptic and memory impairments, and ferroptosis in seven-month-old APP/PS1 mice.ConclusionsCollectively, tFNAs inhibited Aβ-mediated ferroptosis and ameliorated cognitive and synaptic impairments in AD mice. tFNAs may serve as novel option to deal with AD.Graphical abstract

No effect of napping on episodic foresight and prospective memory in kindergarten children.

Preschool children often have problems in remembering to carry out a planned behaviour. This study investigated the impact of napping on episodic foresight (planning for future events) and prospective memory (remembering to perform an action in the future) in 2-3-year-old children. In a quasi-experimental design, we compared children who napped (nap condition, n = 20) after receiving information about an upcoming problem (episodic foresight task) and a delayed intention (prospective memory task) with those who stayed awake (wake condition, n = 43). We hypothesised that napping would improve performance in the episodic foresight and the prospective memory tasks. Contrary to the hypothesis, napping did not significantly affect children's episodic foresight or prospective memory performance, even after controlling for the group difference in age. Task performance was primarily explained by memory effects and age. Further research that incorporates stricter controls and evaluates pre-nap memory strength is necessary fully to elucidate the complex interplay between napping, age, episodic foresight, and prospective memory performance in young children.