For decades, memory research has centered on the role of neurons, which do not function in isolation. However, astrocytes play important roles in regulating neuronal recruitment and function at the local and network levels, forming the basis for information processing as well as memory formation and storage. In this review, we discuss the role of astrocytes in memory functions and their cellular underpinnings at multiple time points. We summarize important breakthroughs and controversies in the field as well as potential avenues to further illuminate the role of astrocytes in memory processes.
Astrocytes ; Neuronal Plasticity/physiology* ; Memory/physiology* ; Neurons/physiology* ; Cognition/physiology*

Evidence suggests that explicit reappraisal has limited regulatory effects on high-intensity emotions, mainly due to the depletion of cognitive resources occupied by the high-intensity emotional stimulus itself. The implicit form of reappraisal has proved to be resource-saving and therefore might be an ideal strategy to achieve the desired regulatory effect in high-intensity situations. In this study, we explored the regulatory effect of explicit and implicit reappraisal when participants encountered low- and high-intensity negative images. The subjective emotional rating indicated that both explicit and implicit reappraisal down-regulated negative experiences, irrespective of intensity. However, the amplitude of the parietal late positive potential (LPP; a neural index of experienced emotional intensity) showed that only implicit reappraisal had significant regulatory effects in the high-intensity context, though both explicit and implicit reappraisal successfully reduced the emotional neural responses elicited by low-intensity negative images. Meanwhile, implicit reappraisal led to a smaller frontal LPP amplitude (an index of cognitive cost) compared to explicit reappraisal, indicating that the implementation of implicit reappraisal consumes limited cognitive control resources. Furthermore, we found a prolonged effect of implicit emotion regulation introduced by training procedures. Taken together, these findings not only reveal that implicit reappraisal is suitable to relieve high-intensity negative experiences as well as neural responses, but also highlight the potential benefit of trained implicit regulation in clinical populations whose frontal control resources are limited.
Humans ; Emotional Regulation ; Electroencephalography ; Evoked Potentials/physiology* ; Cognition/physiology* ; Emotions/physiology*

Audiovisual integration is a vital information process involved in cognition and is closely correlated with aging and Alzheimer's disease (AD). In this review, we evaluated the altered audiovisual integrative behavioral symptoms in AD. We further analyzed the relationships between AD pathologies and audiovisual integration alterations bidirectionally and suggested the possible mechanisms of audiovisual integration alterations underlying AD, including the imbalance between energy demand and supply, activity-dependent degeneration, disrupted brain networks, and cognitive resource overloading. Then, based on the clinical characteristics including electrophysiological and imaging data related to audiovisual integration, we emphasized the value of audiovisual integration alterations as potential biomarkers for the early diagnosis and progression of AD. We also highlighted that treatments targeted audiovisual integration contributed to widespread pathological improvements in AD animal models and cognitive improvements in AD patients. Moreover, investigation into audiovisual integration alterations in AD also provided new insights and comprehension about sensory information processes.
Animals ; Humans ; Alzheimer Disease/pathology* ; Brain/pathology* ; Aging/physiology* ; Cognition

Alzheimer's disease (AD) is a typical cognitive disorder with an increasing incidence in recent years. AD is also one of the main causes of disability and death of the elderly in current aging society. One of the most common symptoms of AD is spatial memory impairment, which occurs in more than 60% of patients. This memory loss is closely related to the impairment of cognitive maps in the brain. The entorhinal grid cells and the hippocampal place cells are important cellular basis for spatial memory and navigation functions in the brain. Understanding the abnormal firing pattern of these neurons and their impaired coordination to neural oscillations in transgenic rodents is crucial for identifying the therapeutic targets for AD. In this article, we review recent studies on neural activity based on transgenic rodent models of AD, with a focus on the changes in the firing characteristics of neurons and the abnormal electroencephalogram (EEG) rhythm in the entorhinal cortex and hippocampus. We also discuss potential cell-network mechanism of spatial memory disorders caused by AD, so as to provide a scientific basis for the diagnosis and treatment of AD in the future.
Animals ; Mice ; Alzheimer Disease/genetics* ; Animals, Genetically Modified ; Cognition ; Cognitive Dysfunction ; Hippocampus/physiology* ; Memory Disorders ; Mice, Transgenic ; Neurons/physiology*

Aging is a natural process accompanied with a progressive deterioration of cognitive functions. With an aging population, more and more elderly people are suffering from cognitive impairment. Previous studies have paid more attention to the impact of inflammation and oxidative stress on cognitive function during aging. Recently, it has been discovered that neurovascular coupling (NVC), a mechanism regulating cerebral blood flow, may play a significant role in aging-related cognitive impairment. NVC responses regulate the supply of energy substances and oxygen during brain activity, which in turn enhances cognitive function. However, as people grow older, NVC responses gradually weaken, which may be one of the mechanisms underlying aging-induced cognitive impairment. Given the important role of NVC responses in the brain, it is necessary to search for intervention methods that can improve NVC responses and promote cognitive function. Exercise is an effective means to delay aging and improve cognitive function. It also has a certain promoting effect on NVC responses. This article reviews the regulatory mechanisms of NVC responses, the relationship between NVC responses and cognitive function, and explores the effects of aging and exercise intervention on NVC responses, hoping to provide new research ideas for exercise intervention to improve NVC responses and promote cognitive function in the elderly.
Humans ; Aged ; Neurovascular Coupling/physiology* ; Aging ; Cerebrovascular Circulation/physiology* ; Cognition ; Brain

With the widespread use of electrical equipment, cognitive functions such as working memory (WM) could be severely affected when people are exposed to 50 Hz electromagnetic fields (EMF) for long term. However, the effects of EMF exposure on WM and its neural mechanism remain unclear. In the present paper, 15 rats were randomly assigned to three groups, and exposed to an EMF environment at 50 Hz and 2 mT for a different duration: 0 days (control group), 24 days (experimental group I), and 48 days (experimental group II). Then, their WM function was assessed by the T-maze task. Besides, their local field potential (LFP) in the media prefrontal cortex (mPFC) was recorded by the in vivo multichannel electrophysiological recording system to study the power spectral density (PSD) of θ and γ oscillations and the phase-amplitude coupling (PAC) intensity of θ-γ oscillations during the T-maze task. The results showed that the PSD of θ and γ oscillations decreased in experimental groups I and II, and the PAC intensity between θ and high-frequency γ (hγ) decreased significantly compared to the control group. The number of days needed to meet the task criterion was more in experimental groups I and II than that of control group. The results indicate that long-term exposure to EMF could impair WM function. The possible reason may be the impaired communication between different rhythmic oscillations caused by a decrease in θ-hγ PAC intensity. This paper demonstrates the negative effects of EMF on WM and reveals the potential neural mechanisms from the changes of PAC intensity, which provides important support for further investigation of the biological effects of EMF and its mechanisms.
Humans ; Rats ; Animals ; Memory, Short-Term/physiology* ; Electromagnetic Fields/adverse effects* ; Prefrontal Cortex ; Cognition

Major depressive disorder (MDD) is characterized by emotion dysregulation. Whether implicit emotion regulation can compensate for this deficit remains unknown. In this study, we recruited 159 subjects who were healthy controls, had subclinical depression, or had MDD, and examined them under baseline, implicit, and explicit reappraisal conditions. Explicit reappraisal led to the most negative feelings and the largest parietal late positive potential (parietal LPP, an index of emotion intensity) in the MDD group compared to the other two groups; the group difference was absent under the other two conditions. MDD patients showed larger regulatory effects in the LPP during implicit than explicit reappraisal, whereas healthy controls showed a reversed pattern. Furthermore, the frontal P3, an index of voluntary cognitive control, showed larger amplitudes in explicit reappraisal compared to baseline in the healthy and subclinical groups, but not in the MDD group, while implicit reappraisal did not increase P3 across groups. These findings suggest that implicit reappraisal is beneficial for clinical depression.
Humans ; Depressive Disorder, Major/psychology* ; Emotional Regulation ; Depression ; Emotions/physiology* ; Cognition/physiology*

Neurocognitive impairment is a group of clinical syndromes characterized by impaired cognitive function and decreased motor ability. Non-pharmacological interventions such as physical exercise have advantages in the treatment of patients with neurocognitive impairment. Multicomponent exercise is a combination of various physical exercises, including strength training, endurance training, balance training and flexibility training, that can improve gait, balance and cardiopulmonary function by increasing muscle mass, strength and endurance in people with neurocognitive impairment, while also reducing the risk of falls in elders. This article reviews the benefits of multicomponent exercise for patients with neurocognitive impairment and its evaluation methods; also describes 4 intervention programs and their clinical application, to provide evidence for clinical practice and promote the application of multicomponent exercise in patients with neurocognitive impairment.
Accidental Falls ; Aged ; Cognition ; Exercise/physiology* ; Gait ; Humans ; Resistance Training

With the increasing prominence of population aging, the cognitive decline of the elderly has gradually become a hotspot of clinical research. As a traditional rehabilitation exercise, Tai Chi has been proved to have a positive effect on improving cognitive function and delaying cognitive decline in the elderly. However, the related brain function mechanism is still unclear. In this paper, we collected studies which observed the changes of Tai Chi on brain regions related to cognitive function in the elderly using magnetic resonance imaging (MRI), electroencephalogram (EEG) and functional near-infrared spectroscopy (fNIRS). We summarized relevant studies from perspective of structural and functional changes in the brain. The results showed that Tai Chi may delay and improve cognitive decline in the elderly by reshaping the structure and function of brain regions related to cognitive function such as memory, attention and execution. The effect of Tai Chi for cognitive function may be associated with positive regulation of cardiovascular function, emotion and meditation level of the elderly. In addition, the improvement of cognitive function further enhances the balance of the elderly. We also found that practice time, frequency and intensity of Tai Chi could be factors influencing the improvement of cognitive function and brain function in the elderly.
Aged ; Attention ; Brain/physiology* ; Cognition ; Humans ; Neuroimaging ; Tai Ji/psychology*

The aim of this paper was to investigate the effect of total saponins from Panax japonicus( SPJ) on cognitive decline of natural aging rats and its mechanism. Thirty male SD rats of eighteen month old were randomly divided into three groups: aged group,10 mg·kg~(-1) SPJ-treated group and 30 mg·kg~(-1) SPJ-treated group. The SPJ-treated groups were given SPJ at the dosages of 10 mg·kg~(-1) and 30 mg·kg~(-1),respectively,from the age of 18 to 24 months. Aged group were lavaged the same amount of saline,10 six-month-old rats were used as control group,with 10 rats in each group. The open field test,novel object recognition and Morris water maze were performed to detect the changes of cognitive function in each group. The changes of synaptic transmission of long-term potentiation( LTP) in hippocampal CA1 region were detected by field potential recording. Western blot was used to detect the protein levels of NLRP3,ASC,caspase-1 and the changes of Glu A1,Glu A2,CAMKⅡ,CREB and phosphorylation of CAMKⅡ,CREB in each group.The results showed that SPJ could improve the decline of cognitive function in aging rats,reduce the damage of LTP in the hippocampal CA1 region of aged rats,and decrease the expression of NLRP3,ASC,caspase-1 in aging rats. At the same time,SPJ could enhance the membrane expression of AMPA receptor( Glu A1 and Glu A2),and increase the expression of p-CAMKⅡand p-CREB in aging rats.SPJ could improve cognitive decline of natural aging rats,and its mechanism may be related to regulating NLRP3 inflammasome,thus regulating the membrane expression of AMPA receptor,and enhancing the expression phosphorylation of CAMKⅡ and CREB.
Aging ; Animals ; CA1 Region, Hippocampal ; physiology ; Cognition ; drug effects ; Inflammasomes ; metabolism ; Long-Term Potentiation ; Male ; NLR Family, Pyrin Domain-Containing 3 Protein ; metabolism ; Panax ; chemistry ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Saponins ; pharmacology