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Neuroscience is the study of the brain. It is an interdisciplinary field. At one level, behavioral tasks are carefully designed to understand behavior and cognition. At other levels, different devices and technologies are used to acquire neural data (the brain communicates via electrical signals) at different scales and link such data to behavior. The interdisciplinary nature is not just evident in the data acquisition but also in the processing and analyses of the data. Signal processing and other system theory-based techniques, statistical methods and computational modeling can be used to identify useful information in brain-acquired signals (electrical, blood flow, volume, etc.) and link them to behavior and cognition in healthy and diseased states. As a field, neuroscience has made numerous meaningful discoveries primarily using the traditional hypothesis driven, top-down, deductive approach. In this approach, the goal is to identify local phenomena that can account for macroscopic (behavioral) effects. This approach provides answers to the specific questions or hypotheses tested. My early work follows this approach. In my first deductive-approach study, I developed a behavioral task that enables controlled delivery of rodent enrichment. I invented an Obstacle Course, which is a track with built-in obstacles that rodents must overcome to complete a lap and receive reward. Comparing this track with traditional enrichment (toys in larger home-cages) we found that animals running this track outperformed animals receiving traditional enrichment. This track then improves upon the rodent model for enrichment, which is used to test the hypothesis that enriched human life experience plays a protective role against myriad debilitating neurological diseases including dementia. In the second deductive-approach study, I analyzed data from surgically implanted depth electrode recordings of electrical brain activity in rats engaged in a behavioral task where they were tested on their memory for a sequence of odors (memory for temporal order). Spectral analysis on this data revealed that the hippocampal area CA1 (a region important for memory processing) recruits power in the 20-40 Hz range during odor-processing, and that the steady-state dynamics of this neural synchrony occurs after a decision is made about temporal order. 20-40 Hz power during this post-decision state increases with knowledge of the odor-sequence. Lastly, machine learning analysis revealed that power in this post-decision state is predictive of sequence memory response accuracy. 20-40 Hz power is generally suggested to gate information within a brain network implicated in a given cognitive process (suppress distractors and maintain representations in facilitating sensori-motor integration); here we extend its role to sequence memory processing in the hippocampus. The third deductive study was similar in nature to the aforementioned one, but in humans. Neural electrical signals were recorded from the brains of patients suffering from epilepsy, using surgically implanted electrodes for clinical monitoring, while they engaged in a memory task. Spectral analysis revealed increased 4-5 Hz power in the hippocampus and neocortex, two key memory systems in the brain, during successful discrimination between similar memories. In this work, it was essential to make inferences about the presence and directionality of interactions between the two memory systems recruiting 4-5 Hz power. This led to my fourth deductive project -- expansion of two methodologies; 1) measuring 4-5 Hz phase transfer entropy but as a function of time, and 2) using the Kalman filter to estimate parameters of a time-varying autoregressive model for subsequent Granger causality analyses – both methods enabled inferences about the direction of communication between the two memory systems. Using these methods, I identified a pattern of directional communication between the hippocampus and neocortex that is consistent with predictions from computational models. These deductive works led to new discoveries. However, I encountered a boundary point in deductive research – I can only know the answers to the specific hypotheses tested. But my knowledge about the general operational range and dynamics of the underlying brain circuits was absent. Given the astounding complexity of the brain, and the numerous behavioral phenomena it supports, deductive approaches alone do not suffice, as they may leave us with incomplete and perhaps misleading information regarding the underlying brain circuits. So I changed my approach to an inductive one.An inductive, bottom-up approach, which is conspicuously absent in the field, reveals physiological rules that link biological phenomena with behavior. I therefore employed Volterra series-based system identification as an inductive approach and comprehensively, agnostically, and rigorously identified the operations of a given brain area, the hippocampal CA1. This was implemented by stimulating and recording from rodent brain slices that were kept live through an artificial physiological environment. Nearly the entirety of the operational range of the CA1 is captured in a single formula, an input-output nonlinear transfer function. Using this function alone, the CA1 output to a random input in a new set of animals can be predicted with high accuracy. Moreover, examining this formula led to new discoveries and provided insight about the CA1 system software, despite this being one of the most heavily studied nodes in the brain. Contrary to the fields popular belief, the formula revealed the presence of system nonlinearity in CA1. Additionally, intuition is gained by examining this formula regarding how the CA1 treats inputs (amplification, suppression, harmonic generation) based on the content of the input.All in all, across species, and using different modalities and approaches I summarize work concerned with first identifying specific neural electrical activity for specific behavior. Then I transition to a different approach -- identifying the fundamental rules of a candidate brain area, capturing nearly the entirety of its processes and operations in a single input-output transfer function. Potential future work could extend this approach to other brain nodes and link them together appropriately based on known anatomical connectivity. An exciting possible outcome of such a research program would be to ultimately characterize the entire brain circuit, through iterative system identification, such that a physically realizable brain can be built.

Emotion regulation and interpersonal psychotherapies that do not require trauma memory processing have been shown to be effective in treating posttraumatic stress disorder (PTSD). This study used a novel method to assess in vivo outcomes in a randomized clinical trial with women (N = 147; ages 18–54; 61% of color; 94% low income) with full (79%) or partial (21%) PTSD. Participants were assigned to affect regulation or interpersonal therapy, or wait-list, and completed daily self-reports for 2 to 4 weeks at baseline and up to 30 days at posttest. Mixed model regression analyses tested pre-post change on five factor analytically derived aggregated daily self-report scores. Emotion regulation-focused therapy was associated with reduced PTSD symptoms, dysregulation, and negative affect, and improvement in adaptive self-regulation and positive affect. Interpersonal-focused therapy was associated with reduced PTSD symptoms and dysregulation. Although both therapies were associated with reduced PTSD symptoms, whether this was due to nonspecific factors rather than the treatments per se could not be determined. Daily self-report data warrant further investigation in psychotherapy research with disorders such as PTSD, in order to assess affective and interpersonal dysregulation and adaptive regulation as they occur in daily life.

We examine the novel hypothesis that physical exercise and sleep have synergistic effects on memory. Exercise can trigger mechanisms that can create an optimal brain state during sleep to facilitate memory processing. The possibility that exercise could counteract the deleterious effects of sleep deprivation on memory by protecting neuroplasticity also is discussed.

In this article, we introduce Mementos the first multimodal corpus for computational modelling of affect and memory processing in response to video content. It was collected online via crowdsourcing and captures 1995 individual responses collected from 297 unique viewers responding to 42 different segments of music videos. Apart from webcam recordings of their upper-body behaviour (totaling 2012 minutes) and self-reports of their emotional experience, it contains detailed descriptions of the occurrence and content of 989 personal memories triggered by the video content. Finally, the dataset includes self-report measures related to individual differences in participants' background and situation (Demographics, Personality, and Mood), thereby facilitating the exploration of important contextual factors in research using the dataset. We describe enumerate 1) the construction and contents of the corpus itself, 2) analyse the validity of its content by investigating biases and consistency with existing research on affect and memory processing, review previously published work that demonstrates the usefulness of the multimodal data in the corpus for research on automated detection and prediction tasks, and 3) provide suggestions for how the dataset can be used in future research on modeling Video-Induced Emotions, Memory-Associated Affect, and Memory Evocation.

Many current treatments for posttraumatic stress disorder (PTSD) emphasize processing and engaging with trauma memories as the key mechanism of therapeutic change. However, promising emerging research indicates links between PTSD symptoms and positive memories. Processing positive memories, to therapeutically impact health outcomes for trauma-exposed individuals, may have several benefits, including (a) increasing access to positive coping mechanisms via activating positive affect and thoughts; (b) addressing avoidance of positive affect and thoughts; and (c) honing skills that will aid in the eventual processing of trauma memories. The present article demonstrates the utility and effects of a novel Processing of Positive Memories Technique (PPMT) with three clients who reported a history of traumatic experiences. We outline the procedures of a 5-session PPMT, that incorporates symptom assessment, detailed imaginal experiencing of positive memories, and processing of associated positive values, affect, strengths, and thoughts. We utilize longitudinal assessment data to demonstrate the clinical benefits of PPMT, such as less PTSD severity, improved mood (e.g., less negative affect), and greater self-esteem. Finally, we discuss treatment considerations based on unique client factors and treatment modalities (i.e., in-person vs. video telehealth).

This article discusses the high-performance near-memory neural network (NN) accelerator architecture utilizing the logic die in three-dimensional (3D) High Bandwidth Memory– (HBM) like memory. As most of the previously reported 3D memory-based near-memory NN accelerator designs used the Hybrid Memory Cube (HMC) memory, we first focus on identifying the key differences between HBM and HMC in terms of near-memory NN accelerator design. One of the major differences between the two 3D memories is that HBM has the centralized through- silicon-via (TSV) channels while HMC has distributed TSV channels for separate vaults. Based on the observation, we introduce the Round-Robin Data Fetching and Groupwise Broadcast schemes to exploit the centralized TSV channels for improvement of the data feeding rate for the processing elements. Using synthesized designs in a 28-nm CMOS technology, performance and energy consumption of the proposed architectures with various dataflow models are evaluated. Experimental results show that the proposed schemes reduce the runtime by 16.4–39.3% on average and the energy consumption by 2.1–5.1% on average compared to conventional data fetching schemes.

STUDY OBJECTIVES: Obstructive sleep apnea (OSA) prevalence increases with age, but whether OSA-related sleep disruption could interrupt the processing of previously encoded wake information thought to normally occur during sleep in cognitively normal older adults remains unknown. METHODS: Fifty-two older (age = 66.9 ± 7.7 years, 56% female), community-dwelling, cognitively normal adults explored a 3-D maze environment and then performed 3 timed trials before (evening) and after (morning) sleep recorded with polysomnography with a 20-minute morning psychomotor vigilance test. RESULTS: Twenty-two (22) participants had untreated OSA [apnea-hypopnea index (AHI4%) ≥ 5 events/h] where severity was mild on average [median (interquartile range); AHI4% = 11.0 (20.7) events/h] and 30 participants had an AHI4% < 5 events/h. No significant differences were observed in overnight percent change in completion time or in the pattern of evening presleep maze performance. However, during the morning postsleep trials, there was a significant interaction between OSA group and morning trial number such that participants with OSA performed worse on average with each subsequent morning trial, whereas those without OSA showed improvements. There were no significant differences in morning psychomotor vigilance test performance, suggesting that vigilance is unlikely to account for this difference in morning maze performance. Increasing relative frontal slow wave activity was associated with better overnight maze performance improvement in participants with OSA (r = .51, P = .02) but not in those without OSA, and no differences in slow wave activity were observed between groups. CONCLUSIONS: OSA alters morning performance in spatial navigation independent of a deleterious effect on morning vigilance or evening navigation performance. Relative frontal slow wave activity is associated with overnight performance change in older participants with OSA, but not those without. CITATION: Mullins AE, Williams MK, Kam K, et al. Effects of obstructive sleep apnea on human spatial navigational memory processing in cognitively normal older individuals. J Clin Sleep Med. 2021;17(5):939–948.

People are known to offload memory processing tasks to devices, such as cameras. We examined whether body-worn cameras (BWCs) are used in this way by police officers. Fifty officers responded to a simulated domestic dispute that resulted in lethal force. Half the sample was provided a BWC and told their footage would be available to assist with post-event recall, but it was later feigned that there was a technological issue. The remaining officers were not equipped with a BWC and thus were aware they would not have any footage to rely on. The amount, accuracy, and type of details reported by officers were coded and subjected to analysis. The results revealed that wearing a camera did not promote cognitive offloading in officers, suggesting that the training officers receive, or other factors that might be unique to policing, may mitigate an effect that has been observed in other contexts.

Paired behavioral and ERP measures were used to track change over time in 17 third- and fourth-grade struggling readers. Word and nonword reading on standardized tests improved, but differentiation of words and letter strings, measured by N170 and N400 amplitude, did not significantly change. Sound awareness scores improved, but the ERP rhyming effect did not significantly change. Both digit span scores and latency of the P300 oddball effect decreased. Correlations between the ostensibly matched behavioral and electrophysiological measures of change were not significant, indicating that use of ERP and behavioral measures can provide nonoverlapping insight into change during reading development.

Background:Cannabidiol (CBD) is being investigated as a potential treatment for several medical indications, many of which are characterised by altered memory processing. However, the mechanisms underlying these effects are unclear.Aims:Our primary aim was to investigate how CBD influences cerebral blood flow (CBF) in regions involved in memory processing. Our secondary aim was to determine if the effects of CBD on CBF were associated with differences in working and episodic memory task performance.Methods:We used a randomised, crossover, double-blind design in which 15 healthy participants were administered 600 mg oral CBD or placebo on separate days. We measured regional CBF at rest using arterial spin labelling 3 h after drug ingestion. We assessed working memory with the digit span (forward, backward) and n-back (0-back, 1-back, 2-back) tasks, and we used a prose recall task (immediate and delayed) to assess episodic memory.Results:CBD increased CBF in the hippocampus (mean (95% confidence intervals) = 15.00 (5.78–24.21) mL/100 g/min, t14= 3.489, Cohen’s d = 0.75, p = 0.004). There were no differences in memory task performance, but there was a significant correlation whereby greater CBD-induced increases in orbitofrontal CBF were associated with reduced reaction time on the 2-back working memory task ( r= −0.73, p = 0.005).Conclusions:These findings suggest that CBD increases CBF to key regions involved in memory processing, particularly the hippocampus. These results identify potential mechanisms of CBD for a range of conditions associated with altered memory processing, including Alzheimer’s disease, schizophrenia, post-traumatic stress disorder and cannabis-use disorders.

Systems memory consolidation describes a gradual process which shifts the dependence of memories from rapidly plastic hippocampal networks to slower-learning neocortical regions for ultimate long-term storage. Sleep is thought to be crucial for this reorganization. Research over the recent years, however, has discovered rapid neocortical plasticity, and thus questions not only the timescales on which systems consolidation occurs, but also the role of sleep therein. At the same time, new ways to manipulate neural activity have furthered our understanding of how different brain areas interact during sleep and have clarified the relevance of this night-time interchange for systems consolidation. Together, these findings suggest that we need to rethink the “wheres” and “whens” of sleep-dependent memory processing.

Alzheimer’s disease (AD) is a neuro-degenerative disease, causing gradual decline in memory function in the affected patients. The loss of memory makes their existence miserable. It is first noticed and reported by the patient’s care takers. The clinicians objectively assess the type and degree of the memory loss by a specific battery of tests, specially designed for the purpose (like Montreal Cognitive Assessment (MoCA) test., Mini-Mental State Exam (MMSE etc.)). Understanding the symptoms of AD, arising out of memory loss, requires deeper insights into what initiates the memory (the sensory inputs from the five sense organs), the different types of memories (explicit, implicit memories, their sub types and associative memory etc.), how the memory signals are modified at the level of the neuron, (analog to digital signals) and the synapse (sensitization, habituation and Long term potentiation / depression etc.), the processing that the inputs received , undergo (encoding, consolidation /organization, storage and retrieval) in higher brain centres (amygdala, hippocampus prefrontal vortex etc.) and also the role played by the various receptors (NMDA, AMPA and the kinase receptors), the neurotransmitters (acetylcholine, Norepineprine, Gama aminobutic acid, serotonin etc.), the central network systems involved (central executive network, salience network, and the default mode network). In short, it is the study all about, of the physiology of memory. The next step is to integrate this knowledge to interpret symptoms of patients with AD. Accordingly, the subject under discussion is dealt with in two parts. Firstly, how the memory is affected in AD and secondly the physiology behind these changes.

Numerous studies have found that previous information can affect the current explicit working memory processing. However, the study that investigate the effect of previous episodes on the implicit working memory processing has been limited. The present study investigated this issue in healthy older adults and patients with mild cognitive impairment (MCI). A hybrid delayed-match-to-sample task was used to examine the implicit working memory processing regardless of explicit memory components. Functional magnetic resonance imaging data was collected. The behavioral results demonstrated that the previously studied information was able to facilitate the following implicit working memory processing. Nevertheless, this effect was impaired in MCI patients, although both healthy older adults and MCI patients have shown significant implicit working memory processing. Whole-brain activation analysis revealed that there were significant interactions between group and previous information (Studied and Non-studied) in the left cuneus. The psychophysiological-interaction analysis showed that the functional connectivity between left cuneus and regions in bilateral middle occipital gyrus as well as dorsal regions of left precuneus was modulated by previous episodic information in healthy older adults. However, no significant region was found in MCI patients. The current study for the first time revealed that the previous episodic information can facilitate the following implicit working memory procession in healthy older adults, and demonstrated the key cortical structure and cortical pathways underlying the interactions between previous episodic information and current implicit working memory processing.

The dentate gyrus is one of the only brain regions that continues its development after birth in rodents. Adolescence is a very sensitive period during which cognitive competences are programmed. We investigated the role of dentate granule neurons (DGNs) born during adolescence in spatial memory and compared them with those generated earlier in life (in embryos or neonates) or during adulthood by combining functional imaging, retroviral and optogenetic tools to tag and silence DGNs. By imaging DGNs expressing Zif268, a proxy for neuronal activity, we found that neurons generated in adolescent rats (and not embryos or neonates) are transiently involved in spatial memory processing. In contrast, adult-generated DGNs are recruited at a later time point when animals are older. A causal relationship between the temporal origin of DGNs and spatial memory was confirmed by silencing DGNs in behaving animals. Our results demonstrate that the emergence of spatial memory depends on neurons born during adolescence, a function later assumed by neurons generated during adulthood.

Purpose of Review Auditory stimulation is a technique that can enhance neural oscillations linked to overnight memory consolidation. In this review, we evaluate the impacts of auditory stimulation on the neural oscillations of sleep and associated memory processes in a variety of populations. Recent Findings Cortical EEG recordings of slow-wave sleep (SWS) are characterised by two cardinal oscillations: slow oscillations (SOs) and sleep spindles. Auditory stimulation delivered in SWS enhances SOs and phase-coupled spindle activity in healthy children and adults, children with ADHD, adults with mild cognitive impairment and patients with major depression. Under certain conditions, auditory stimulation bolsters the benefits of SWS for memory consolidation, although further work is required to fully understand the factors affecting stimulation-related memory gains. Recent work has turned to rapid eye movement (REM) sleep, demonstrating that auditory stimulation can be used to manipulate REM sleep theta oscillations. Summary Auditory stimulation enhances oscillations linked to overnight memory processing and shows promise as a technique for enhancing the memory benefits of sleep.

Many studies have focused on the role of the medial entorhinal cortex (MEC) in spatial memory and spatial processing. However, more recently, studies have suggested that the functions of the MEC may extend beyond the spatial domain and into the temporal aspects of memory processing. The current study examined the effect of MEC lesions on spatial and nonspatial tasks that require rats to learn and remember information about location or stimulus-stimulus associations across short temporal gaps. MEC- and sham-lesioned male rats were tested on a watermaze delayed match to position (DMP) task and trace fear conditioning (TFC). Rats with MEC lesions were impaired at remembering the platform location after both the shortest (1 min) and the longest (6 h) delays on the DMP task, never performing as precisely as sham rats under the easiest condition and performing poorly at the longest delay. On the TFC task, although MEC-lesioned rats were not impaired at remembering the conditioning context, they showed reduced freezing in response to the previously associated tone. These findings suggest that the MEC plays a role in bridging temporal delays during learning and memory that extend beyond its established role in spatial memory processing.

In this article we reconsider Homer’s poetry in the light of modern achievements in neuroscience. This perspective offers some clues for examining specific patterns of brain functioning. Homer’s epics, for instance, painted a synthetic picture of the human body, emphasizing some parts and neglecting others. This led to the formation of a body schema reminiscent of a homunculus, which we call the “Homeric homunculus.” Both poems were largely the product of centuries of oral tradition, in which the prodigious memory of courtly rhapsodists was essential to the performance of the epics. The underlying cognitive functions required a close interplay of memory and language skills, supported by the musical and rhythmic cadence of Homeric verse.

The success of direct brain stimulation as a treatment for neurological disorders such as Parkinson's Disease has led to increased interest in developing stimulation-based therapeutic applications for other cognitive domains, such as learning and memory. Here, we review recent advances in using stimulation for memory modulation and enhancement in humans. An expanded set of stimulation targets have been studied that can modulate broad memory networks and behavioral performance. Using online neural decoding during memory processing, closed-loop systems have been used to deliver stimulation with greater precision and improve behavioral outcomes. The data suggest strategies for future therapeutic applications to treating memory dysfunction.

When exploring new environments animals form spatial memories that are updated with experience and retrieved upon re-exposure to the same environment. The hippocampus is thought to support these memory processes, but how this is achieved by different subnetworks such as CA1 and CA3 remains unclear. To understand how hippocampal spatial representations emerge and evolve during familiarization, we performed 2-photon calcium imaging in mice running in new virtual environments and compared the trial-to-trial dynamics of place cells in CA1 and CA3 over days. We find that place fields in CA1 emerge rapidly but tend to shift backwards from trial-to-trial and remap upon re-exposure to the environment a day later. In contrast, place fields in CA3 emerge gradually but show more stable trial-to-trial and day-to-day dynamics. These results reflect different roles in CA1 and CA3 in spatial memory processing during familiarization to new environments and constrain the potential mechanisms that support them., To understand how spatial representations emerge and evolve across hippocampal subfields, we compared trial-to-trial dynamics of place cells in CA1 and CA3 in new environments and across days. CA1 place fields form early, shift backwards and partially remap across days whereas in CA3 they develop gradually and are more stable, suggesting distinct functional roles in representing space.

Objective: To investigate neuropsychological functioning in children with and without Specific Learning Disorder. Methods: The comparative cross-sectional study was conducted in schools affiliated with Punjab Education Foundation, Gujrat, Pakistan, from January –to June 2019, and comprised children diagnosed with Specific Learning Disorder and age-matched and class matched high achievers as controls. Bender Gestalt Test II with copy test, recall test, perceptual test and motor test subscales was administered on both the groups for the assessment of neuropsychological functioning. Data was analysed using SPSS 21. Results: Of 116 subjects, 64(55.2%) were cases and 52(44.8%) controls. Overall, there were 64(55.2%) girls and 52(44.8%) boys with a mean age of 10.41(SD=1.14). There was significant difference on recall test (p

A cardinal feature of Post-traumatic stress-related disorder (PTSD) is a paradoxical memory alteration including both intrusive emotional hypermnesia and declarative/contextual amnesia. Most preclinical, but also numerous clinical, studies focus almost exclusively on the emotional hypermnesia aiming at suppressing this recurrent and highly debilitating symptom either by reducing fear and anxiety or with the ethically questionable idea of a rather radical erasure of traumatic memory. Of very mixed efficacy, often associated with a resurgence of symptoms after a while, these approaches focus on PTSD-related symptom while neglecting the potential cause of this symptom: traumatic amnesia. Two of our preclinical studies have recently demonstrated that treating contextual amnesia durably prevents, and even treats, PTSD-related hypermnesia. Specifically, promoting the contextual memory of the trauma, either by a cognitivo-behavioral, optogenetic or pharmacological approach enhancing a hippocampus-dependent memory processing of the trauma normalizes the fear memory by inducing a long-lasting suppression of the erratic traumatic hypermnesia.

Objective: Posttraumatic stress disorder (PTSD) symptoms may impact cognitive processes underlying encoding and retrieval of positive memories. Contractor and colleagues thus proposed a Positive Memory-PTSD model outlining hypothesized pathways (e.g., improved cognitions and affect) linking active processing of positive memories and PTSD symptoms. In the current study, we empirically explored direct and indirect pathways of the Positive Memory-PTSD model including relations between presence/types of processing memory methodology, posttrauma maladaptive cognitions, positive/negative affect, and PTSD symptom severity. Methods: We randomly assigned 65 students reporting trauma histories to time-matched narrating (identifying and sharing details of elicited positive memories), writing (identifying and writing details of elicited positive memories), or control conditions. Participants completed self-report measures (T0) and repeated their assigned task condition and self-report measures 6-8 days later (T1). Results: Half-longitudinal models demonstrated direct associations of (1) being in the narrating versus other conditions with decreases in posttrauma maladaptive cognitions and negative affect, and increases in positive affect; and (2) increases in posttrauma maladaptive cognitions and negative affect with greater PTSD symptom severity. Although, when controlling for posttrauma maladaptive cognitions and negative/positive affect, being in the narrating versus other conditions was associated with decreases in PTSD symptom severity, these constructs did not explain examined relations. Conclusions: Results suggest beneficial impacts of narrating positive memories on PTSD symptom severity (accounting for cognitions/affect) and improved cognitions/affect, and a need to examine moderating variables (e.g., emotion regulation) in the Positive Memory-PTSD model. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Receiver operating characteristic (ROC) analysis is the standard tool for studying recognition memory. In particular, the curvilinearity and the y-offset of recognition ROC curves have been interpreted as indicative of either memory strength (single-process models) or different memory processes (dual-process model). The distinction between familiarity and recollection has been widely studied in cognitive neuroscience in a variety of conditions, including lesions of different brain regions. We develop a computational model that explicitly shows how performance in recognition memory is affected by a complex and, as yet, underappreciated interplay of various factors, such as stimulus statistics, memory processing, and decision-making. We demonstrate that (1) the factors in the model affect recognition ROC curves in unexpected ways, (2) fitting R and F parameters according to the dual-process model is not particularly useful for understanding the underlying processes, and (3) the variability of recognition ROC curves and the controversies they have caused might be due to the uncontrolled variability in the contributing factors. Although our model is abstract, its functional components can be mapped onto brain regions, which are involved in corresponding functions. This enables us to reproduce and interpret in a coherent framework the diverse effects on recognition memory that have been reported in patients with frontal and hippocampal lesions. To conclude, our work highlights the importance of the rich interplay of a variety of factors in driving recognition memory performance, which has to be taken into account when interpreting recognition ROC curves.

Introduction: We hypothesized that diabetic patients without mild cognitive impairment would present deficiencies in visuospatial incidental/intentional memory processing and alterations in the und...

The relationship between space, time, and memory is discernable in many urban design theories, many projects, and many urbanism initiatives. By integrating the three, we see how interacting systems are developed, primarily through spatial and temporal aspects of memory development and memory processing (Eichenbaum, 2017).

During the first year of life, infants devote the majority of their time to sleep. Research in adults has shown that sleep supports a variety of memory processes. Surprisingly, sleep's function for infant memory has only started to receive attention in research. In this chapter, we will describe age-related changes in sleep and in memory processing over the first years of life, as well as methods to capture both sleep and memory. Then, we will review current findings on the effects of sleep on memory processing in infants. Lastly, we will also point out gaps in current knowledge and describe potential avenues for future research. Overall, the results of recent experimental studies provide evidence that timely, extended napping is involved in how memories are encoded and stored in the long-term and contribute to the formation of knowledge networks in infants.

Optoelectronic synapses integrating synaptic and optical-sensing functions exhibit large advantages in neuromorphic computing for visual information processing and complex learning, recognition, and memory in an energy-efficient way. However, electric stimulation is still essential for existing optoelectronic synapses to realize bidirectional weight-updating, restricting the processing speed, bandwidth, and integration density of the devices. Herein, a two-terminal optical synapse based on a wafer-scale pyrenyl graphdiyne/graphene/PbS quantum dot heterostructure is proposed that can emulate both the excitatory and inhibitory synaptic behaviors in an optical pathway. The simple device architecture and low-dimensional features of the heterostructure endow the optical synapse with robust flexibility for wearable electronics. This optical synapse features a linear and symmetric conductance-update trajectory with numerous conductance states and low noise, which facilitates the demonstration of accurate and effective pattern recognition with a strong fault-tolerant capability even at bending states. A series of logic functions and associative learning capabilities have been demonstrated by the optical synapses in optical pathways, significantly enhancing the information processing capability for neuromorphic computing. Moreover, an integrated visible information sensing memory processing system based on the optical synapse array is constructed to perform real-time detection, in situ image memorization, and distinction tasks. This work is an important step toward the development of optogenetics-inspired neuromorphic computing and adaptive parallel processing networks for wearable electronics.