Memory Performance Research Articles

NXP031 restores memory function by dual effects degrading Aβ accumulation and facilitating antioxidant pathway in Alzheimer's disease models

Alzheimer’s disease (AD) is a representative neurodegenerative disease that is characterized by the overaccumulation of amyloid beta (Aβ) proteins. Since AD is accompanied by excessive oxidative stress, which aggravates neurological pathologies, the use of antioxidants has been considered to prevent disease development. NXP031, a combination of vitamin C (VitC) and an optimized aptamer that binds to VitC and stabilizes the reactivity of VitC, was designed. This study aimed to evaluate the effects of NXP031 on AD pathology, including Aβ accumulation, Aβ-induced oxidative stress, neuronal damage, and neuroinflammation. When NXP031 was administered to 5xFAD transgenic mice, NXP031 exerted a strong inhibitory action on Aβ accumulation, superior to that of VitC, by inducing an increase in Aβ-degrading endopeptidase expression. NXP031 diminished lipid peroxidation levels, activated Nrf2-mediated antioxidant pathways, and suppressed overactivated neuroinflammation. An in vitro study using Neuro2a cells revealed that NXP031 protects the cells against oxidative stress by regulating the MAPK signaling pathway-mediated apoptosis. Additionally, the neuroprotective effects of NXP031 were confirmed in a dose-dependent manner when administered to intrahippocampal Aβ-injected mice, as NXP031 attenuated memory decline, neuronal apoptosis, synaptic degeneration, and excessive glial activation, and reduced NOX-2 expression in the hippocampus. Taken together, NXP031 reduced the Aβ burden by regulating Aβ-degeneration and attenuated memory impairment, neuronal death, synaptic degeneration, and neuroinflammation induced by Aβ toxicity. These results suggest the potential of NXP031 as a therapeutic agent for AD.

Gradient Mo1−xWxSe2 monolayer Alloys: Synthesis and multifunctional applications

With the continuous and rapid development of electronic information technology, the demand for new materials with miniaturization, high integration, high performance, and multifunction is becoming increasingly urgent. However, it is difficult for existing photodetectors based on a single material to achieve multi-functionality while maintaining excellent performance, and the devices based on heterostructures are faced with complex preparation and compatibility problems. In this work, gradient Mo1−xWxSe2 monolayer alloys with high crystal quality have been synthesized by an evaporation-assisted chemical vapor deposition method. The composition of the synthesized Mo1−xWxSe2 monolayer alloys varies gradually with x ranging from 0 to 1. The Mo1−xWxSe2 based photodetector shows superior photoresponse performance in the visible wavelength with maximum responsivity of 26 A/W and external quantum efficiency up to 6320 % under 520 nm laser irradiation. Besides, the Mo1−xWxSe2 device is capable of high-resolution imaging, which can be used as image sensor. Moreover, nonvolatile memory function has also been realized in the device because the band gap of Mo1−xWxSe2 can be effectively adjusted by the gradient distribution of the component and the deep energy levels caused by Se vacancies can be modulated to shallow energy levels. A thrilling discovery is that the gradient Mo1−xWxSe2 alloy device can simulate the biological synapses successfully, including paired-pulse facilitation, short-term plasticity, long-term plasticity and learning process. The realization of high-performance photodetection, visualization, nonvolatile memory and synaptic simulation based on a single gradient crystal offers a new type of material to develop advanced optoelectronic devices with multiple functions.

Machine learning in additive manufacturing——NiTi alloy’s transformation behavior

The laser powder bed fused NiTi alloys (LPBF-NiTi) demonstrate shape memory functionality and superelasticity as a result of their distinctive phase transition characteristics. Nevertheless, achieving precise control and regulation of the phase transition temperature poses a challenge, influenced by factors like powder composition and process parameter. In this study, a feature screening strategy and machine learning (ML) method were employed to predict and regulate the phase transition temperature of LPBF-NiTi alloy, offering a more efficient and cost-effective alternative to traditional experimental methods of regulation and control. Specifically, accuracy analysis was performed on LPBF-NiTi phase transition datasets with varying compositions and process conditions utilizing generalized regression neural network (GRNN), and other methods. The findings indicate that the interpretable features extracted through the selection strategy outlined in this study when combined with the GRNN model, demonstrate a high level of prediction accuracy (R2 = 0.97). To investigate the accuracy of the model, this study utilized various process parameters to fabricate NiTi alloys with different compositions from Ni50.8Ti49.2 alloy powder. Using this model, the study identified a novel, larger window of optimal LPBF processing that allows for controllable complex phase transitions.

Limited carry-over effects of socioemotional manipulations on subsequent unrelated memory tasks.

Although age is typically associated with significant impairments in memory performance, several domains exist in which these impairments are reduced or even eliminated. These "pockets of preservation" in older adults' memory can be seen in tasks involving socioemotional processing and may be supported by distinct encoding or retrieval modes relative to neutral content. The current study examines whether engaging in socioemotional tasks prior to encoding or retrieval allows older adults to enter an encoding or retrieval mode that better supports memory performance. In two online studies, adults across the lifespan were asked to complete a memory task where they incidentally encoded and retrieved neutral (Experiment 1, N = 1621) or emotional (Experiment 2, N = 409) word-image pairs. Participants were randomly assigned to a control (i.e., no manipulation), pre-encoding, or pre-retrieval socioemotional manipulation condition. There were no main effects of manipulation condition, suggesting that such manipulations may not reliably enhance memory. However, future research is needed to follow up on exploratory analyses that highlighted particular conditions under which these manipulations may convey benefits. There were also no age-by-manipulation interactions. While these null effects may suggest that these manipulations are not better suited to older adults, this may also be a result of the unexpected age-related increases (Experiment 1) and age invariance (Experiment 2) in overall memory accuracy in the current study. Socioemotional manipulations should also be examined in older adults who underperform younger adults.

Efficacy and Mechanism of Schisandra chinensis Fructus Water Extract in Alzheimer's Disease: Insights from Network Pharmacology and Validation in an Amyloid-β Infused Animal Model.

Schisandra chinensis Fructus (SCF) is a traditional medicinal herb containing lignans that improves glucose metabolism by mitigating insulin resistance. We aimed to investigate the therapeutic potential and action mechanism of SCF for Alzheimer's disease (AD) using a network pharmacology analysis, followed by experimental validation in an AD rat model. The biological activities of SCF's bioactive compounds were assessed through a network pharmacology analysis. An AD rat model was generated by infusing amyloid-β peptide (Aβ) (25-35) into the hippocampus to induce Aβ accumulation. The AD rats were fed either 0.5% dextrin (AD-Con) or 0.5% SCF (AD-SCF group) in a high-fat diet for seven weeks. The rats in the normal/control group received an Aβ (35-25) infusion (no Aβ deposition) and were fed a control diet (Normal-C). Aβ deposition, memory function, inflammation, and glucose/lipid metabolism were evaluated. The network analysis revealed significant intersections between AD-related targets and bioactive SCF compounds, like gomisin A, schisandrin, and longikaurin A. Key AD genes prostaglandin-endoperoxide synthase-2 (PTGS2, cyclooxygenase-2) and acetylcholinesterase (AChE) were linked to SCF compounds. In the rats with AD induced by bilaterally infusing amyloid-β (25-35) into the hippocampus, the 0.5% SCF intake mitigated hippocampal amyloid-β deposition, neuroinflammation, memory deficits, and dysregulated glucose and lipid metabolism versus the AD controls. SCF reduced hippocampal AChE activity, inflammatory cytokine expression related to PTGS2, and malondialdehyde contents and preserved neuronal cell survival-related factors such as brain-derived neurotrophic factor and ciliary neurotrophic factor similar to normal rats. The neuroprotective effects validated the network analysis findings. SCF could be a potential AD therapeutic agent by activating the parasympathetic nervous system to reduce hippocampal oxidative stress and inflammation, warranting further clinical investigations of its efficacy.

Effects of active breaks on educational achievement in children with and without ADHD: study protocol and rationale of the Break4Brain project

The Break4Brain project aims to elucidate the effects of both acute and chronic physical activity (PA) on educational achievement in children with and without Attention Deficit Hyperactivity Disorder (ADHD). This study will be conducted in two phases: a cross-over design followed by a hybrid type 1 implementation-effectiveness trial, which includes both a cluster randomized controlled trial (RCT) and a qualitative study. In phase I, 60 children aged 10–12, with 30 each from ADHD and non-ADHD groups, will participate in a laboratory-based study over 4 days within 1 month. They will participate in three counterbalanced experimental conditions: (i) PA with cognitive engagement, (ii) PA without cognitive engagement, and (iii) a cognitively engaging control. This phase will assess acute changes in brain function, academic performance, working memory, inhibitory control, and sustained attention. Phase II will involve 600 children aged 10–12, randomly assigned to either a video-based PA program or a control group (300 children per group) in an 8-week cluster RCT. This phase will also incorporate a qualitative approach to explore the implementation context through pre- and post-intervention semi-structured interviews with teachers and school staff, and questionnaires for students. The outcomes of interest in this phase will include working memory, cognitive flexibility, selective attention, and academic performance. For the cross-over study, we hypothesize that PA conditions will enhance the studied outcomes compared to the control condition. In the RCT, we anticipate that the 8-week active breaks program will result in significant improvements in the selected outcomes compared to the control group. This study is expected to make pioneering contributions by including novel variables and focusing on the ADHD population. Furthermore, if the cluster RCT proves effective, it could offer a practical and cost-effective resource for integrating active breaks into daily school routines.

Postmodern Vision of Absolute Truth in "Atonement" by Ian McEwan

This paper explores Ian McEwan's "Atonement" and its postmodern interpretation of the concept of ultimate truth. The novel, which takes place in the early 20th century, examines the difficulties associated with memory, narrative, and the search for the truth. This essay examines how the novel reflects the postmodern rejection the idea of ultimate truth through a study of the text. It is possible to see the novel "Atonement" as a postmodern attack on the idea of ultimate truth. It is proposed that the novel's postmodern is a conception of reality highlights the importance of memory and narrative in the construction of truth. This paper is important because it applies postmodernism theory to the novel "Atonement" by Ian McEwan, giving it a fresh viewpoint. The study underlines the significance of subjective experiences and viewpoints in our perception of reality and underscores the function of memory and narrative in truth construction. Postmodernism theory is used as a literary movement that rejects the conventional belief in objective truth and emphasizes the importance of subjectivity and fragmentation in understanding of reality. This paper attempts to analyze the notion of absolute truth in Ian McEwan's novel. The primary aim of this paper is to examine the postmodern vision of absolute truth in "Atonement" and its implications for our understanding of truth and reality. This paper aims to demonstrate how the novel challenges traditional notions of truth and offers a vision of truth that is subjective and fragmented.

The neurocognitive correlates of DTI indicators of white matter disorganization in pediatric moderate-to-severe traumatic brain injury.

Neuroimaging has expanded our understanding of pediatric brain disorders in which white matter organization and connectivity are crucial to functioning. Paralleling the known pathobiology of many neurodevelopmental disorders, traumatic brain injury (TBI) in childhood can alter trajectories of brain development. Specifically, diffusion tensor imaging (DTI) studies in TBI have demonstrated white matter (WM) abnormalities that suggest microstructural disruptions that may underlie atypical neurodevelopment. The neurocognitive correlates of these previous findings will be explored in this study. Indicators of WM organization were collected in 44 pediatric patients with moderate/severe TBI and 76 controls over two post-injury time points: T1 (8-20 weeks) and T2 (54-96 weeks). Our previous work identified two TBI subgroups based on information processing differences: one with slower interhemispheric transfer times (IHTT) of visual information than controls and another with comparable IHTT. We extend this prior work by evaluating neurocognitive trajectories associated with divergent WM structure post-injury in slow and normal IHTT TBI subgroups. At T1, both TBI subgroups performed significantly worse than controls on a norm-referenced working memory index (WMI), but only the Normal IHTT TBI subgroup significantly improved over the 12-month follow-up period (p = 0.014) to match controls (p = 0.119). In contrast, the Slow IHTT TBI subgroup did not show any recovery in working memory performance over time and performed more poorly than the control group (p < 0.001) at T2. Improvement in one of the two WMI subtests was associated with DTI indicators of WM disorganization in CC tracts to the precentral, postcentral, frontal, and parietal cortices. IHTT and WM mean diffusivity predicted 79% of the variance in cognitive recovery from T1 to T2 when also accounting for other known predictors of TBI recovery. In the year following TBI, some pediatric patients experienced persisting working memory disturbance while others exhibited recovery; stratification was based on an event-related potential marker. More or less improvement in neurocognition was also associated with the degree of WM disorganization. IHTT, measured post-acutely after TBI, and progression of WM disorganization over time predicted neurocognitive trajectories at the chronic timeframe - potentially representing a prognostic biomarker.

Neurocognitive correlates of cerebral mitochondrial function and energy metabolism using phosphorus magnetic resonance spectroscopy in older adults.

The goal of the current study was to learn about the role of cerebral mitochondrial function on cognition. Based on established cognitive neuroscience, clinical neuropsychology, and cognitive aging literature, we hypothesized mitochondrial function within a focal brain region would map onto cognitive behaviors linked to that brain region. To test this hypothesis, we used phosphorous (31P) magnetic resonance spectroscopy (MRS) to derive indirect markers of mitochondrial function and energy metabolism across two regions of the brain (bifrontal, left temporal). We administered cognitive tasks sensitive to frontal-executive or temporal-hippocampal systems to a sample of 70 cognitively unimpaired older adults with subjective memory complaints and a first-degree family history of Alzheimer's disease and predicted better executive function and recent memory performance would be related to greater frontal and temporal 31P MRS indirect markers, respectively. Results of separate hierarchical linear regressions indicated better recent memory scores were related to 31P MRS indirect markers of lower static energy and higher energy reserve within the left temporal voxel; these findings were associated with moderate effect sizes. Contrary to predictions, executive function performance was unrelated to 31P MRS indirect markers within the bilateral frontal voxel, which may reflect a combination of theoretical and/or methodological issues. Findings represent a snapshot of the relationship between cognition and 31P MRS indirect markers of mitochondrial function, providing potential avenues for future work investigating mitochondrial underpinnings of cognition. 31P MRS may provide a sensitive neuroimaging marker for differences in aspects of memory among persons at-risk for mild cognitive impairment or dementia.

Icariin is a potential neurodegenerative candidate against ammonia–glutamate excitotoxicity–oxidative stress pathway

BackgroundHepatic encephalopathy (HE) is a pathological state characterized by the abrupt or chronic failure of the liver. This study intends to conduct a comparative analysis of potential benefits of icariin (ICA), a primary component of flavonoids found in the Chinese medicinal plant Epimedium, with silymarin (SLY) as a hepatic and brain support agent in a model of HE rats, focusing on assessment of the behavioral and biochemical effects. Thioacetamide (TAA) was given intraperitoneally to rats at a dosage of 200 mg/kg on three separate days to induce HE. Oral gavage of silymarin or ICA (100 mg/kg) was given daily for 14 days following HE induction. All rats underwent behavioral assessments (open field and Y maze). Estimates were made for hepatic functions and brain cortex oxidative stress indicators as well as cytochrome c and caspase-3.ResultsThe findings demonstrated that the administration of ICA to rodents with HE induced by TAA led to a recovery of hepatic enzymes activities and behavioral adjustments as shown by an improvement in locomotor and memory functions. Furthermore, Icariin demonstrated a reduction in cortex biochemical indicators through the amelioration of hyperammonemia and enhancement of antioxidant status. This was achieved by reducing malondialdehyde, calcium, nitric oxide contents and downregulating lactate dehydrogenase activities. In addition, ICA maintains alteration of glutamate and glutamine contents.ConclusionICA suggested to possess the capacity to serve as a beneficial hepatotherapeutic and neurotherapeutic adjunct in brain disorders associated with hyperammonemia–glutamate-mediated excitotoxicity.

Depression Symptoms Moderate Associations between Daily Functioning and Neuropsychological Performance in Mexican American Adults.

The influence of depression on the relationship between cognition and daily living in aging Mexican American adults requires further investigation, given projected trends in general growth as well as prevalence of depression and Alzheimer's disease and related dementias (ADRD) in this population. In the present study, we examined the extent to which depression (assessed using the Geriatric Depression Scale - 15 item version) moderated the association between reported daily functioning (assessed using the Functional Activities Questionnaire [FAQ]) and objective neuropsychological performance in aging Mexican American adults in the National Alzheimer's Coordinating Center cohort. Worse reported daily functioning (higher FAQ scores) was associated with worse memory and language performance among participants without elevated depression symptoms (ps < .05), but no associations were observed among those with elevated symptoms (ps > .05). Moreover, depression did not moderate associations of reported daily functioning with performance in attention and working memory or executive functioning and processing speed (ps > .05). Aging Mexican American adults with elevated depression symptoms may have subjective informant reports of daily functioning that are discrepant from their objective performance on formal tests of memory and language. Within the context of neuropsychological evaluations for ADRD, failure to adequately assess mood to inform the nature of cognitive and/or functional changes could result in misdiagnosis and lead to delayed, premature, and/or improper intervention with this population.

A new concept of structural smart fabric activated by shape memory alloys

Abstract This work presents the development, prototyping and validation of a new concept of structure called Structural Smart Fabric (SSF). An SSF is a chainmail fabric composed by interconnected elements, called cells, which can be stiffened by reactive elements, such as those made by Shape Memory Alloy (SMA). Exploiting the shape memory functionality, SSFs are capable of sensing and reacting to external stimuli. Based on this concept, in this study we propose an SSF that integrates SMA wires into a 3D-printed chainmail structure. The shape memory effect of these wires is used as an actuating mechanism that, at high temperature, tightens the adjacent cells together and provides increased structural stiffness. In this study, finite element simulations were initially conducted to enhance the comprehension of the SSF’s mechanical behaviour. The influence of the initial cell spacing on the SSF stiffness and the wire stress profiles was evaluated during bending loading, as well as the evolution of contact pressure profiles between adjacent cells. This numerical approach enabled to tune the design of the SSF prototypes which were successively manufactured using Selective Laser Sintering (SLS) additive manufacturing technology with PA12. After the integration with the SMA wires, the SSF prototypes were tested under a 3-point bending configuration at different temperatures. The results revealed a remarkable increase in structural stiffness at elevated temperatures compared to ambient conditions. This study set the basis for a deeper understanding of SSF's unique capabilities and potential applications in fields where adaptive and responsive structures are required.&amp;#xD;

Ethyl gallate ameliorates diabetes-induced Alzheimer's disease-like phenotype in rats via activation of α7 nicotinic receptors and mitigation of oxidative stress

Cognitive decline, an important comorbidity of type 2 diabetes (T2D), is attributed to oxidative stress and impaired cholinergic signaling in the brain. The α7 nicotinic acetylcholine receptor (α7nAChR) is densely distributed in the hippocampus and cortex, and exerts neuroprotective and procognitive actions. Ethyl gallate (EG), a natural phenolic antioxidant compound, showed high in-silico binding affinity towards α7nAChR and brain penetrability. Therefore, the present study aimed to evaluate the involvement of α7nAChR in the potential of EG to ameliorate T2D-induced Alzheimer's disease-like condition. T2D was induced by intraperitoneal (i.p.) injection of streptozotocin (35 mg/kg) in rats on high-fat diet. Diabetic animals were treated with EG (10 and 20 mg/kg, i.p.) for four weeks, and their learning and memory performance was evaluated by the Morris water maze (MWM). Further, the brains were subjected to biochemical analysis of antioxidants like glutathione (GSH), superoxide dismutase (SOD), and catalase (CAT), and oxidative stress marker malonaldehyde (MDA). While diabetic rats showed a significant decline in cognitive performance in the MWM, a substantial improvement was noticed following EG treatment. Further, the diabetes-associated reductions in GSH, SOD, and CAT levels, along with increased MDA contents in the brain, were effectively restored by EG. Interestingly, pre-treatment with α7nAChR antagonist methyllycaconitine (1 mg/kg, i.p.) attenuated the effects of EG on behavioral and biochemical parameters. The results suggest that EG may augment cholinergic signaling in the brain via α7nAChR to mitigate oxidative stress, consequently alleviating T2D-associated dementia. Therefore, EG could be a potential candidate for addressing cognitive impairment comorbid with T2D.

Impact of Neuropsychological Assessment on Subjective Memory Complaints in Patients With Mild Cognitive Impairment.

Patients with Alzheimer's disease (AD), namely at an initial stage like amnestic cognitive impairment (aMCI), typically present with memory complaints. They also have difficulties regarding self-knowledge about their cognitive deficits. In clinical practice, a formal neuropsychological assessment is often done. The present study aimed to understand whether patients with aMCI retain the ability to monitor the success or failure in their performance during the neuropsychological assessment and adjust the report of memory complaints accordingly, as compared to healthy controls. Participants were patients with aMCI and healthy controls who were questioned about their own memory abilities using the Subjective Memory Complaints (SMC) scale, applied before and after the neuropsychological assessment protocol. A repeated measures General Linear Model was performed to analyze changes in SMC (within-subjects effects) after the neuropsychological assessment, in patients with aMCI and healthy controls (between-subjects effects). Eighty volunteers, 40 patients with aMCI and 40 healthy controls, participated in the study. Patients with aMCI showed lower MMSE scores, more depressive symptoms, and deficits in memory and learning, language and executive domains. Patients with aMCI had higher SMC scores [9.4(3.6)] than healthy controls [4.4(2.3)] before the neuropsychological assessment. A statistically significant interaction was found between the SMC and the diagnostic group, meaning that healthy controls decreased SMC [3.4(1.9)] after the neuropsychological assessment, whereas patients with aMCI kept high levels of SMC [9.6(3.9)]. In patients with aMCI, an inverse correlation between logical memory and the change in SMC was found, so that patients with lower scores in the logical memory test tended to increase their memory complaints after the assessment. Both patients with aMCI and healthy controls can monitor and update the impression about their memory abilities following a formal neuropsychological assessment. Patients with aMCI maintain a high SMC level, which is inversely associated with their memory performance. In practical terms, SMC should be measured consistently at a particular moment in time, preferably preceding the objective neuropsychological assessment.

Application of Multi-Input Multi-Output Brain-Computer Interface in Cognitive Assessment for Alzheimer’s Disease

This research aims to augment human cognitive abilities, particularly memory function, through the development of innovative prosthetics. The hippocampus, a crucial brain region involved in memory encoding and recall, has been the focal point of numerous studies seeking to develop prosthetics that can restore or enhance memory function in individuals with impairments such as Alzheimer’s disease. This review examines two studies that delve into the development and application of hippocampal neural prosthetics, highlighting the potential of these prosthetics to revolutionize the treatment of memory impairments. One study utilized static neural stimulation patterns to enhance memory for specific information content, while another developed a nonlinear Multiple Input Multiple Output (MIMO) dynamic model to predict and stimulate neural activity patterns during memory encoding. Both studies demonstrated significant improvements in memory performance. Additionally, this paper discusses the clinical significance and application prospects of hippocampal neural prosthetics, including the potential for implantable prosthetics and the widespread applicability of MIMO stimulation. Furthermore, the paper explores advanced modeling and classification techniques for neural ensembles and visual memory decoding, including Volterra-type hierarchical modeling, optimal multi-unit stimulation patterns, and a sparse classification model for decoding visual memories. Finally, the paper presents the implementation and evaluation of neural prosthesis systems, including an application-specific integrated circuit (ASIC) design for a hippocampal prosthesis and a high-performance, scalable system architecture for real-time estimation of neural activity. These advancements hold promise for future research and applications in neural prosthetics for memory enhancement.

Transition metal doping for tailoring magnetic properties of graphdiyne

Tailoring the magnetic properties of semiconductors is crucial for realizing spintronic devices with integrated logic and memory functions. Graphdiyne (GDY), a two-dimensional carbon semiconductor, has emerged as a promising material for this purpose. This work demonstrates an effective approach to induce robust room-temperature ferromagnetism in GDY through in-situ transition metal (Fe, Co, Ni) doping via an improved liquid-liquid interface synthesis method. Density functional theory calculations reveal that the ferromagnetism originates from the Kagome lattice formed by the doped transition metal atoms. Remarkably, Fe-doped GDY exhibits a saturation magnetization of 2.86 emu · g−1 at room temperature, substantially higher than Co- and Ni-doped counterparts. Furthermore, post synthesis annealing treatment allows modulating the magnetic properties by introducing hydroxyl groups, with Co-GDY annealed at 500°C showing optimal room-temperature ferromagnetic behavior (0.26 emu · g−1). This work paves the way for tailoring magnetic semiconductors for spintronic applications by leveraging transition metal doping and defect engineering in graphdiyne.

Retelling of Stories with Common Phrasal Expressions by High-Proficiency Learners: Implications for Learning and High-Stakes Testing

The goal of this research was to investigate how well L2 English speakers of different proficiency levels were able to perform on a test of auditory memory like that used in the Wechsler Memory Scale (WMS). In this test, participants must retell heard stories. While the validity of elicited imitation tests is well established in second-language acquisition research, the effectiveness of using retelling as a neuropsychological measurement when a language other than the test taker’s L1 is used is unclear. Further, due to their importance in memory function, this study also analyzed the role of common phrasal expressions in how well participants retold stories in three groups of different proficiency. The results indicated that the increase in scores in the retelling of stories aligned with the proficiency level of the non-native participants. Higher-proficiency NNSs were also able to use more of the commonly used spoken phrases in their retelling. Further, there was no difference in this measure between the higher-proficiency Second-Language English and First-Language English participants. While the effectiveness of this test method as a neuropsychological tool when a language other than the test taker’s L1 is used is unclear, these results indicate significant progress by the higher-proficiency participants. Nevertheless, given that this test is often used in this context with immigrants and minority language patients, doubts remain about its suitability for less proficient individuals.

Chronic Sleep Deprivation Altered the Expression of Memory-Related Genes and Caused Cognitive Memory Dysfunction in Mice.

Lack of sleep, whether acute or chronic, is quite common and negatively affects an individual's memory and cognitive function. The question of whether chronic sleep deprivation (CSD) causes cognitive impairment to arise and progress is not well studied. To investigate the effects of CSD on memory and cognition, this study began by establishing a CSD mouse model. Behavioral experiments on animals revealed that CSD induced cognitive behavioral abnormalities reminiscent of Alzheimer's disease. Western blot experiments further demonstrated a considerable increase in amyloid-β (Aβ) expression in the mouse brain following CSD. Meanwhile, the hub gene Prkcg was searched for in the cerebellum using RNA-seq and bioinformatics analysis. PKCγ (Prkcg) expression was significantly reduced, as demonstrated by RT-qPCR and Western blot validations. Additionally, CSD was associated with downregulated CREB expression, decreased expression of the endothelin-converting enzyme (ECE1), and increased phosphorylation of ERK1/2 downstream of PKCγ. These findings suggested that CSD down-regulated PKCγ expression, decreased ECE1 expression, impaired Aβ degradation, and affected the PKCγ/ERK/CREB pathway and the synthesis of memory-related proteins. Overall, this study highlighted how CSD modulated PKCγ-related metabolism, impacting Aβ clearance and the production of memory-related proteins. Such insights are crucial for understanding and preventing sporadic Alzheimer's disease (sAD) associated with CSD.

Application of Electrical Stimulation in BCI in Patients with Alzheimer’s Disease

This paper systematically discusses the application prospect of neuromodulation technology in the treatment of Alzheimer’s disease (AD). It focuses on the potential role of various techniques, including transcutaneous electrical nerve stimulation (TENS), deep brain stimulation (DBS), repeated transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (tDCS), in improving the cognitive function of AD patients. With the aggravation of the global aging problem, the incidence of AD is increasing year by year, and the existing treatment methods are difficult to effectively prevent the progress of the disease. Studies have shown that technologies such as TENS and DBS can improve patients’ memory and cognitive function to some extent. For example, a study by Smith et al. (2020) found that DBS applied to the fornix resulted in a 20% improvement in memory scores over a 6-month period. However, due to the small sample size and inconsistent experimental design, the universality and reliability of the existing research results are still limited. Future studies should aim for larger, more diverse sample sizes and standardized experimental protocols to enhance the robustness of findings. This article reviews the latest research results of these neuromodulation techniques, emphasizing the importance of optimizing treatment parameters and expanding the scale of clinical trials. The paper is structured as follows: first, this paper discusses each neuromodulation technique in detail; then, this paper analyzes their potential benefits and limitations; finally, this paper provides recommendations for future research directions.

Memristive Artificial Synapses Based on Brownmillerite for Endurable Weight Modulation.

Exploring a computing paradigm that blends memory and computation functions is essential for artificial synapses. While memristors for artificial synapses are widely studied due to their energy-efficient structures, random filament conduction in general memristors makes them less preferred for endurability in long-term synaptic modulation. Herein, the topotactic phase transition (TPT) in brownmillerite-phased (110)-SrCoO2.5 (SCO2.5) is harnessed to enhance the reversibility of oxygen ion migration through 1-D oxygen vacancy channels. By employing a heteroepitaxial structured 2-terminal configuration of Au/SCO2.5/SrRuO3/SrTiO3, the brownmillerite SCO2.5-based synapse artificial synapses are exploited. Demonstration of the TPT behavior is corroborated by comparing oxygen migration energy by density-functional theory calculations and experimental results, and by monitoring the voltage pulse-induced peak shift in the Raman spectra of SCO2.5. With the voltage pulse-driven TPT behaviors, it is reliably characterized by linear, symmetric, and endurable long-term potentiation and depression performances. Notably, the durability of the TPT-based weight control mechanism is demonstrated by achieving consistent and noise-free weight updates over 32 000 iterations across 640 cycles. Furthermore, learning performances based on deep neural networks and convolutional neural networks on various image datasets yielded very high recognition accuracy. The work offers valuable insights into designing memristive synapses that enable reliable weight updates in neural networks.