Memory Errors Research Articles

Performance analysis of several common error correction codes

With the rapid development of information technology and advances in science and technology, people are constantly interacting with data and coding. Error correction codes are integral to ensuring the security, robustness, and accuracy of information and systems, used not only in various engineering fields but in our daily lives as well. Systems that incorporate error correction codes have been proven to perform significantly better than those that do not, which makes it essential to understand the principles behind coding, encoding techniques, and their performance in specific domains.This paper focuses on three widely used error correction codes: Hamming code, RS code, and convolutional code. By introducing each code separately and evaluating their performance in different practical areas using proper simulations and relevant research results, this paper provides a comprehensive understanding of the vital role of error correction codes in channel encoding. Each code has its strengths, weaknesses, and specific applications. Hamming code, for example, is suitable for correcting bit errors in computer memories and communication systems. RS code is widely used in digital storage and broadcast systems due to its high level of error correction capability. Convolutional code is ideal for correcting bit-errors in continuous channels, making it an excellent choice for wireless communication systems. Overall, the results demonstrate that these error correction codes are crucial to guaranteeing data transmission integrity and system robustness. Understanding their principles and performance can guide future research and development of coding techniques in advancing technological progress and improving our daily lives.

Characterizing and Improving Resilience of Accelerators to Memory Errors in Autonomous Robots

Motion planning is a computationally intensive and well-studied problem in autonomous robots. However, motion planning hardware accelerators (MPA) must be soft-error resilient for deployment in safety-critical applications, and blanket application of traditional mitigation techniques is ill-suited due to cost, power, and performance overheads. We propose Collision Exposure Factor (CEF), a novel metric to assess the failure vulnerability of circuits processing spatial relationships, including motion planning. CEF is based on the insight that the safety violation probability increases with the surface area of the physical space exposed by a bit-flip. We evaluate CEF on four MPAs. We demonstrate empirically that CEF is correlated with safety violation probability, and that CEF-aware selective error mitigation provides 12.3 ×, 9.6 ×, and 4.2 × lower dangerous Failures-In-Time rate on average for the same amount of protected memory compared to uniform, bit-position, and access-frequency-aware selection of critical data. Furthermore, we show how to employ CEF to enable fault characterization using 23, 000 × fewer fault injection (FI) experiments than exhaustive FI, and evaluate our FI approach on different robots and MPAs. We demonstrate that CEF-aware FI can provide insights on vulnerable bits in an MPA while taking the same amount of time as uniform statistical FI. Finally, we use the CEF to formulate guidelines for designing soft-error resilient MPAs.

Are False Memory and Creative Thinking Mediated by Common Neural Substrates? An fMRI Meta-Analysis

ABSTRACT Episodic retrieval plays a functional-adaptive role in supporting divergent creative thinking, the ability to creatively combine different pieces of information. However, the same constructive memory process that provides this benefit can also lead to memory errors. Prior behavioral work has shown that there is a positive correlation between the false recognition of lure items in the Deese-Roediger-McDermott paradigm, and divergent creative thinking as assessed on the alternate uses task. Here, we conducted a meta-analysis of functional magnetic resonance imaging studies to test for convergence in the neural substrates associated with these cognitive linkages. Our individual meta-analyses of false recognition-related activity as well as divergent thinking-related neural activity replicated prior meta-analyses. However, there was no significant statistical overlap across the neural regions associated with false recognition and divergent creative thinking. These null findings may reflect the operation of distinct generative retrieval processes engaged during divergent thinking relative to false recognition.

Intrusive-like memory errors associate with positive schizotypy

Schizophrenia is characterized by memory impairments, yet the relationships between its distinct symptom clusters (i.e., positive, negative, disorganized) and specific aspects of memory dysfunction remain poorly characterized. In the present study, we compiled a large analog sample (N = 795) to test whether positive symptoms, versus negative and disorganized symptoms, were uniquely and differentially related to false alarm versus miss errors during recognition memory. Mixed-effects beta regression analyses revealed that both positive schizotypy and paranoia were more strongly associated with false alarms than misses. Disorganized schizotypy showed a similar pattern, though to a lesser extent; negative schizotypy showed a significant relationship with neither false alarm nor miss errors. We suggest that those higher in positive schizotypy are especially prone to misattribute signal to noise stimuli during recognition memory – characteristic of an “intrusive-like” profile of memory impairment, wherein context-irrelevant stimuli trigger spurious retrieval events – and speculate on the neural processes that might give rise to this asymmetry.

H - 29 Delivering Culturally Sensitive Neuropsychological Assessment Feedback: a Case Study of Atypical Neurosyphilis.

To demonstrate the neuropsychological correlates of atypical neurosyphilis and the importance of delivering assessment results in a culturally sensitive manner. The patient was a 52-year-old African American male with 12years of education who was raised in a rural, southern town and worked as a delivery driver. He was hospitalized after three weeks of altered mental status, memory loss, and seizures. Electroencephalography (EEG) showed left lateralized periodic discharges. Magnetic resonance imaging (MRI) showed hyperintensities in the left hippocampus and amygdala consistent with limbic encephalitis. Cerebrospinal fluid studies revealed lymphocytic pleocytosis and hypoglycorrhachia. Rapid plasma regain and venereal disease tests were positive for syphilis in serum and CSF. He was initially treated with empiric antibiotics and antiseizures medications with modest improvement. His mental status improved after penicillin treatment, and he was discharged after 14days. Repeat MRI showed cortical atrophy in the left medial frontal lobe and left hippocampus. The patient demonstrated executive dysfunction (e.g., set-loss and source memory errors) and poor performance across verbal and visual memory tasks. He also demonstrated an inaccurate understanding of the possible causes of his illness. Feedback was delivered across two sessions: one session to discuss test results and a second session with the patient and his wife to discuss syphilis as a sexually transmitted infection and address the historical context of syphilis among African American men. Neurosyphilis can present as limbic encephalitis and can mimic autoimmune encephalitis and other infectious diseases. Tailoring assessment feedback to a patient's sociocultural context is vital for encouraging continued treatment.

Treadmill exercise prevents the hyperexcitability of pyramidal neurons in medial entorhinal cortex in the 3xTg-AD mouse model of Alzheimer's disease

Neuronal hyperactivity is a key abnormality in early stage Alzheimer's disease (AD). Medial entorhinal cortex (mEC) plays a vital role in memory function and is affected early in AD. Growing evidence indicates benefits of regular exercise on memory and cognitive function in humans with AD, although, the underlying mechanisms are not clear. Therefore, this study was designed to test the effects of 16 weeks treadmill exercise on spatial learning memory and the underlying cellular mechanisms in 6-month-old 3xTg-AD mice. Whole-cell patch clamp was used to examine neuronal intrinsic excitability, spontaneous excitatory postsynaptic currents (sEPSCs) and spontaneous inhibitory postsynaptic currents (sIPSCs) of mEC layer II/III pyramidal neurons in the following groups: wild type (WT + sham), 3xTg-AD (AD+sham), WT receiving exercise (WT + Ex), and AD receiving exercise (AD+Ex). We found that at a behavioral level, treadmill exercise decreased working memory errors in radial arm maze (RAM) test in 6-month-old AD mice. At a cellular level, we found that treadmill exercise prevented the abnormal increase in mEC pyramidal neuron input resistance and action potential firing in 6-month-old 3xTg-AD mice compared with WT + sham and AD+Ex mice; further, sEPSC amplitude and frequency were normal in AD+Ex but overactive in AD+sham; additionally, GABAergic inhibition was normal in AD+Ex mice but reduced in AD+sham. In conclusion, our results indicate that treadmill exercise improves spatial learning memory and prevents network hyperexcitability in mEC by reducing pyramidal neuronal intrinsic excitability and normalizing excitatory and inhibitory synaptic transmission in 3xTg-AD mice.

Extended trajectory of spatial memory errors in typical and atypical development: The role of binding and precision.

Spatial reconstruction, a method for evaluating how individuals remember the placement of objects, has traditionally been evaluated through the aggregate estimation of placement errors. However, this approach may obscure the nature of task errors. Specifically, recent data has suggested the importance of examining the precision of responses, as well as absolute performance on item-context bindings. In contrast to traditional analysis approaches based on the distance between the target and the reconstructed item, in this study we further explored three types of errors (swap error, global error, and local distance) that may all contribute to the distance, with particular emphasis on swap errors and local distance due to their associations with item-context bindings and memory precision, respectively. We examined these errors in children aged 3-18 years, making comparisons between children with typical development (TD) and children with Down syndrome (DS), a population with known memory challenges. As expected, older children outperformed younger children in terms of overall memory accuracy. Of importance is that we measured uneven maturational trajectories of memory abilities across the various error types. Specifically, both remembered locations (irrespective of object identity) and swap errors (object-location binding errors) align with the overall memory accuracy. Memory precision, as measured by local distance in simpler set size 2 trials, mirrored overall memory accuracy. However, for more complex set size 3 trials, local distance remained stable before age 8 and showed age-related change thereafter. The group with DS showed reduced precision compared to a TD matched group, and measures of precision, and to a lesser extent binding errors, correlated with standard neuropsychological outcomes. Overall, our study contributed to a fine-grained understanding of developing spatial memory ability in a large sample of typical developing children and a memory impaired population. These findings contribute to a growing body of research examining precision as a key factor in memory performance.

Insdel codes from subspace and rank-metric codes

Insertion and deletion (insdel in short) codes are designed to deal with synchronization errors in communication channels caused by insertions and deletions of message symbols. These codes have received a lot of attention due to their applications in diverse areas such as computational biology, DNA data storage, race-track memory error corrections, language processing, and synchronous digital communication networks. In the present work, we study constructions and limitations of insdel codes from rank metric and subspace codes. This paper studies and improves the idea of the work [4] by Hao Chen on the connection between insdel codes and subspace codes.We discuss why subspace code is a natural choice for constructing insdel codes and show that the interleaved Gabidulin codes can be used to construct nonlinear insdel codes approaching the Singleton bound. Then we show that the indexing scheme of transforming efficient Hamming metric codes to efficient insdel codes can be adapted for the class of rank metric codes. And that improves the base field size of the construction of insdel codes from lifted rank-metric codes. It is also shown that the size of the insdel code from a subspace code can be improved significantly than in the previously proposed construction. We give an algebraic condition for a linear Gabidulin rank metric code to be optimal insdel code adapting the condition proved for Reed-Solomon codes. Moreover, we give constructions of linear and nonlinear insdel codes from Sidon spaces.

Mechanism of Bugansan Decoction in ameliorating learning and memory impairment in D-galactose-induced aging rats based on AGEs/RAGE/NF-κB pathway

ObjectiveTo investigate the underlying mechanism of the compound Bugansan Decoction (补肝散, BGSD) in intervening learning and memory in D-galactose (D-gal)-induced aging rats. MethodsA total of 40 rats were randomly assigned to four groups: control, model, BGSD [14.06 g/(kg·d)], and piracetam [0.4 g/(kg·d)] groups, with 10 rats in each group. D-gal [400 mg/(kg·d)] was injected intraperitoneally to establish the aging rat model. The rats' body weight, water intake, food intake, and gripping strength were recorded each week. The eight-arm maze and step-down test were used to measure the rats' capacity for learning and memory. Liver, thymus, spleen, and brain tissues were weighed to calculate the corresponding organ indices; serum malondialdehyde (MDA) content and superoxide dismutase (SOD) activity were measured. Hematoxylin and eosin (HE) staining was adopted to observe the pathological changes of the hippocampus; enzyme-linked immunosorbent assay (ELISA) was used to detect the levels of tumor necrosis factor (TNF)-α, interleukin (IL)-6, and IL-1β in the hippocampus. Real-time quantitative polymerase chain reaction (RT-qPCR) was used to detect the expression of receptors for advanced glycation end products (RAGE), nuclear factor-κB (NF-κB), TNF-α, IL-6, and IL-1β mRNA in the hippocampus. Western blot (WB) was employed to detect the expression levels of advanced glycation end products (AGEs), RAGE, and NF-κB protein in the hippocampus. ResultsIn D-gal-induced aging rats, BGSD significantly increased food intake, water intake, body weight, gripping strength, and organ indices (P < 0.05), and significantly decreased working memory error (WME), reference memory error (RME), and total memory errors (TE) in an eight-arm maze (P < 0.05). In the step-down test, step-down latency was prolonged and the frequency of errors dropped (P < 0.05). Additionally, BGSD could lessen the harm done to hippocampus neurons, increase serum SOD activity, lower MDA levels, and down-regulate the expression levels of the pro-inflammatory molecules TNF-α, IL-6, and IL-1β (P < 0.05). Further findings showed that BGSD significantly decreased hippocampal AGEs, RAGE, and NF-κB expression (P < 0.05). ConclusionBy blocking the AGEs/RAGE/NF-κB signaling pathway, BGSD may regulate the neuroinflammatory damage in D-gal-induced aging rats, and thus improve learning and memory.

Exploration of Bitflip’s Effect on Deep Neural Network Accuracy in Plaintext and Ciphertext

Neural Networks (NNs) are increasingly deployed to solve complex classification problems and produce accurate results on reliable systems. However, its accuracy quickly degrades in the presence of bit flips from memory errors or targeted attacks on DRAM main memory. Prior work has shown that a few bit errors significantly reduce NN accuracies, but it is unclear which bits have an outsized impact on network accuracy and why. This paper first investigates the relationship of the number representation for NN parameters with the impacts of bit flips on NN accuracy. We then explore the Bit Flip Detection (BFD) framework— four software-based error detectors that detect bit flips independent of NN topology. We discuss exciting findings and evaluate the various detectors’ efficacy, characteristics, and trade-offs.

EEG-based neural networks approaches for fatigue and drowsiness detection: A survey

Drowsiness is a state of fatigue or sleepiness characterized by a strong urge to sleep. It is correlated with a progressive decline in response time, compromised processing of available information, more errors in short-term memory, and reduced vigilance behaviors. The electroencephalogram (EEG), a recording of the brain’s electrical activities, has demonstrated the most robust association with drowsiness. As a result, EEG is widely recognized as a dependable indicator for evaluating drowsiness, fatigue, and performance levels. In this survey paper, we thoroughly investigate the application of shallow and deep neural network approaches utilizing EEG signals for the detection of fatigue and drowsiness. As far as our knowledge extends, this is the pioneering survey paper dedicated to exploring this specific research domain. The paper presents a comprehensive overview of the diverse EEG features utilized in the detection of fatigue and drowsiness, the different types of neural networks, and the reported performance of these methods in the literature. Additionally, the paper thoroughly examines the challenges and limitations associated with EEG-based fatigue and drowsiness detection and highlights directions for future research. The survey aims to offer a comprehensive overview of the existing methods in EEG-based fatigue and drowsiness detection, serving as a valuable resource for researchers and practitioners working in the respective field.

I lie because I am good at: psychopathic traits do not influence the effects of fabrication on memory

ABSTRACT Studies have shown that lying can detrimentally affect memory. For example, when people fabricate a false account, this fabrication can turn into a false memory. The current experiment aimed to examine whether the typical effects on memory due to fabrication depend on psychopathy traits. 232 participants completed the Personality Psychopathy Inventory-Revised and watched a mock crime video. Subsequently, participants had to imagine being interviewed as the main suspect of the crime by either telling the truth or lying about the crime. After one-week, all participants were instructed to tell the truth. Fabrication led to false memories. Specific psychopathy traits influenced the recall in that higher psychopathic traits were associated with worse event-related memory (i.e. less correct details and more memory errors). However, psychopathic traits did not intervene in the mnemonic effects of fabrication. Findings can be useful for legal practitioners who deal with statements’ reliability.

Blockage of calcium-sensing receptor improves chronic intermittent hypoxia-induced cognitive impairment by PERK-ATF4-CHOP pathway

Obstructive sleep apnea-hypopnea syndrome (OSAHS) is involved in cognitive impairment of children. Chronic intermittent hypoxia (CIH) is considered as the critical pathophysiological mechanism of OSAHS. Calcium sensitive receptor (CaSR) mediated apoptosis in many neurological disease models by endoplasmic reticulum stress (ERS)-related pathway. However, little is known about the role of CaSR in OSAHS-induced cognitive dysfunction. In this study, we explored the effect of CaSR on CIH-induced cognitive impairment and possible mechanisms on regulation of PERK-ATF4-CHOP pathway in vivo and in vitro. CIH exposed for 9 h in PC12 cells and resulted in the cell apoptosis, simulating OSAHS-induced neuronal injury. CIH upregulated the level of CaSR, p-PERK, ATF4 and CHOP, contributing to the cell apoptosis. Treated with CaSR inhibitor (NPS-2143) or p-PERK inhibitor (GSK2656157) before CIH exposure, CIH-induced PC12 cell apoptosis was alleviated via inhibition of CaSR by downregulating p-PERK, ATF4 and CHOP. In addition, we established CIH mice model. With CIH exposure for 4 weeks in mice, more spatial memory errors were observed during 8-arm radial maze test. CIH significantly increased apoptotic cells in hippocampus via upregulating cleaved Caspase-3 and downregulating ratio of Bcl-2 to Bax. Besides, treatment of CaSR inhibitor alleviated the hippocampal neuronal apoptosis following CIH with downregulated p-PERK, ATF4 and CHOP, suggesting that CaSR contributed to CIH-induced neuronal apoptosis in hippocampus via ERS pathway. Sum up, our results demonstrated that CaSR accelerated hippocampal apoptosis via PERK-ATF4-CHOP pathway, holding a critical function on CIH-mediated cognitive impairment. Conversely, inhibition of CaSR suppressed PERK-ATF4-CHOP pathway and alleviated cognitive impairment.

Effects of long-term individual housing of middle-aged female Octodon degus on spatial learning and memory in the Barnes maze task.

Prolonged social isolation is a form of passive chronic stress that has consequences on human and animal behavior. The present study was undertaken to elucidate whether the long-term isolation would precipitate age-related changes in anxiety and spatial learning and memory in degus. We investigated the effects of long-term social isolation on anxiety levels in the light-dark test, and spatial orientation abilities in the Barnes maze. Middle-aged female Octodon degus were allocated to either group-housed (3 animals per cage) or individually-housed for 5 months. Under this experimental condition, there were no significant group differences in the anxiety level tested in the light-dark test and in the motivation to escape from the Barnes maze. There were no significant differences in cortisol levels between individually- and group-housed animals. On the last acquisition training day of spatial learning, individually- housed animals had a significantly higher number of correct responses and a smaller number of reference and working memory errors than the group-housed animals. In addition, isolated animals showed a tendency for reference and working memory impairment on the retention trial, while group-housed degus showed improvement in these parameters. The present study indicates that prolonged social isolation during adulthood in female degus has a dual effect on spatial orientation. Specifically, it results in a significant improvement in acquisition skills but a slight impairment in memory retention. The obtained cognitive changes were not accompanied by modification in anxiety and cortisol levels.

Visual similarity structure a priori predicts memory errors for novel high-dimensional face stimuli

Visual similarity structure a priori predicts memory errors for novel high-dimensional face stimuli

Observation inflation and interrogative suggestibility: Different but related memory errors

Observation inflation and interrogative suggestibility: Different but related memory errors

Spatial Scene Memories Are Biased Towards a Fixed Amount of Semantic Information.

Scene memory has known spatial biases. Boundary extension is a well-known bias whereby observers remember visual information beyond an image's boundaries. While recent studies demonstrate that boundary contraction also reliably occurs based on intrinsic image properties, the specific properties that drive the effect are unknown. This study assesses the extent to which scene memory might have a fixed capacity for information. We assessed both visual and semantic information in a scene database using techniques from image processing and natural language processing, respectively. We then assessed how both types of information predicted memory errors for scene boundaries using a standard rapid serial visual presentation (RSVP) forced error paradigm. A linear regression model indicated that memories for scene boundaries were significantly predicted by semantic, but not visual, information and that this effect persisted when scene depth was considered. Boundary extension was observed for images with low semantic information, and contraction was observed for images with high semantic information. This suggests a cognitive process that normalizes the amount of semantic information held in memory.

Rate-distortion theory of neural coding and its implications for working memory.

Rate-distortion theory provides a powerful framework for understanding the nature of human memory by formalizing the relationship between information rate (the average number of bits per stimulus transmitted across the memory channel) and distortion (the cost of memory errors). Here we show how this abstract computational-level framework can be realized by a model of neural population coding. The model reproduces key regularities of visual working memory, including some that were not previously explained by population coding models. We verify a novel prediction of the model by reanalyzing recordings of monkey prefrontal neurons during an oculomotor delayed response task.

Proces twórczy i sekrety błędów

This text presents a very special creative process, which is an absolute exception in world literature. It is about the formation of My Century by Aleksander Wat and about various types of errors that were revealed during the preparation of the new edition of this work. The errors that appear in previous editions of My Century are of a varied nature. These are primarily “memory errors” of the author himself, there are also errors resulting from faulty listening to the recordings or technical faults in several recordings, and finally errors that are difficult to classify and explain, and which may be associated with exceptional difficulties with establishing the facts.

Prevalence of Handwriting Difficulty among Second Grade School Students in North Chennai: A Cross-sectional Study

Abstract Background: Handwriting is one of the important skills, i.e., a child needs to meet the needs of the elementary school classroom. Handwriting difficulties affect children’s school performance. The prevalence of handwriting difficulties among the school children was 34%. Handwriting, a complicated perceptual-motor skill, requires a variety of talents, including visual-motor coordination, motor planning, cognitive and perceptual skills, as well as tactile and kinesthetic sensitivity. A child spends 30%–60% of their school day performing fine motor activities, mainly handwriting activities. Occupational therapy services are often recommended for children with handwriting problems. Handwriting interventions commonly focus on learning, acquisition, and maintaining a new skill. Thus, this study interprets the handwriting difficulties among school-going children. Objective: The objective of this study is to estimate the prevalence of handwriting difficulty among second grade school students in North Chennai. Study Design: The study design was a cross-sectional study. Methods: The students were selected based on the selection criteria. Multistage sampling method was used. The North Chennai wards were chosen first, and then, the areas within them, using the table of random numbers. The lottery method was used to choose a total of 9 schools and a total of 821 students were included. Prior to the child’s participation in the study, the parent’s consent was obtained. Then, the Screener of Handwriting Proficiency and student assessment were administered to all the participants. The collected data were analyzed and results were inferred. Results: Handwriting difficulty was prevalent among 240 students which accounted to be 29.2% of second grade students, while 581 students with 70.8% were found to have without handwriting difficulty. Out of 459 male students, 172 students (37.5%) and a total of 363 female students, 68 students (18.8%) have handwriting difficulty. Comparatively, male students were found to have more difficulty than female students. This difference of observation was identified statistically significant which denotes gender contributing factor with respect to handwriting difficulty. Conclusion: This study concludes that handwriting difficulties were more prevalent in boys than in girls. Errors in memory were more remarked when compared to other components and placement component was found to have least errors.