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Behavioural Neurology 2020Patients with Alzheimer's Disease (AD) not only are suffering from amnesia but also are prone to memory distortions, such as experiencing detailed and vivid... (Review)
Review
Patients with Alzheimer's Disease (AD) not only are suffering from amnesia but also are prone to memory distortions, such as experiencing detailed and vivid recollections of episodic events that have never been encountered (i.e., false memories). To describe and explain these distortions, we offer a review to synthesize current knowledge on false memory in AD into a framework allowing for better understanding of the taxonomy and phenomenology of false memories and of the cognitive mechanisms that may underlie false memory formation in AD. According to this review, certain phenomenological characteristics of memories (e.g., high emotional load, high vividness, or high familiarity) result in misattributions in AD. More specifically, this review proposes that generalized decline in cognitive control and inhibition in AD may result in difficulties in suppressing irrelevant information during memory monitoring, especially when irrelevant (i.e., false) information is characterized by high emotion, vividness, or familiarity. This review also proposes that binding deficits in AD decrease the ability to retrieve relevant contextual details, leading to source monitoring errors and false memories. In short, this review depicts how phenomenological characteristics of memories and failures of monitoring during retrieval contribute to the occurrence of false memory in AD.
Topics: Alzheimer Disease; Amnesia; Humans; Inhibition, Psychological; Memory; Memory Disorders; Memory, Episodic; Mental Recall; Neuropsychological Tests
PubMed: 32148564
DOI: 10.1155/2020/5284504 -
Journal of Integrative Neuroscience Jan 2022Converging evidence from biopsychosocial research in humans and animals demonstrates that chronic sensory stimulation (via excessive screen exposure) affects brain... (Review)
Review
Digital dementia in the internet generation: excessive screen time during brain development will increase the risk of Alzheimer's disease and related dementias in adulthood.
Converging evidence from biopsychosocial research in humans and animals demonstrates that chronic sensory stimulation (via excessive screen exposure) affects brain development increasing the risk of cognitive, emotional, and behavioural disorders in adolescents and young adults. Emerging evidence suggests that some of these effects are similar to those seen in adults with symptoms of mild cognitive impairment (MCI) in the early stages of dementia, including impaired concentration, orientation, acquisition of recent memories (anterograde amnesia), recall of past memories (retrograde amnesia), social functioning, and self-care. Excessive screen time is known to alter gray matter and white volumes in the brain, increase the risk of mental disorders, and impair acquisition of memories and learning which are known risk factors for dementia. Chronic sensory overstimulation (i.e., excessive screen time) during brain development increases the risk of accelerated neurodegeneration in adulthood (i.e., amnesia, early onset dementia). This relationship is affected by several mediating/moderating factors (e.g., IQ decline, learning impairments and mental illness). We hypothesize that excessive screen exposure during critical periods of development in Generation Z will lead to mild cognitive impairments in early to middle adulthood resulting in substantially increased rates of early onset dementia in later adulthood. We predict that from 2060 to 2100, the rates of Alzheimer's disease and related dementias (ADRD) will increase significantly, far above the Centres for Disease Control (CDC) projected estimates of a two-fold increase, to upwards of a four-to-six-fold increase. The CDC estimates are based entirely on factors related to the age, sex, race and ethnicity of individuals born before 1950 who did not have access to mobile digital technology during critical periods of brain development. Compared to previous generations, the average 17-19-year-old spends approximately 6 hours a day on mobile digital devices (MDD) (smartphones, tablets, and laptop computers) whereas individuals born before 1950 at the same age spent zero. Our estimates include the documented effects of excessive screen time on individuals born after 1980, Millennials and Generation Z, who will be the majority of individuals ≥65 years old. An estimated 4-to-6-fold increase in rates of ADRD post-2060 will result in widespread societal and economic distress and the complete collapse of already overburdened healthcare systems in developed countries. Preventative measures must be set in place immediately including investments and interventions in public education, social policy, laws, and healthcare.
Topics: Adolescent; Adult; Aged; Alzheimer Disease; Amnesia; Brain; Child; Cognitive Dysfunction; Human Development; Humans; Middle Aged; Screen Time; Young Adult
PubMed: 35164464
DOI: 10.31083/j.jin2101028 -
Korean Journal of Anesthesiology Aug 2022Intravenous anesthetic agents such as midazolam, propofol, and ketamine are routinely used to provide anesthesia and sedation. They have been shown to effectively induce... (Review)
Review
Intravenous anesthetic agents such as midazolam, propofol, and ketamine are routinely used to provide anesthesia and sedation. They have been shown to effectively induce and maintain amnesia, sedation, and hypnosis in various patient groups and clinical settings. However, all anesthetic agents have the potential to cause unwanted side effects such as hemodynamic instability, respiratory depression, or slow recovery due to prolonged post-procedural sedation. Remimazolam, a recently approved benzodiazepine for general anesthesia and procedural sedation in Korea, has been successfully used for these purposes. To date, inconclusive knowledge has been obtained regarding the use of remimazolam in different patient populations and under various surgical conditions. With respect to the specific pharmacokinetic and pharmacodynamic characteristics of remimazolam, the use of remimazolam is expected to increase providing safe general anesthesia and sedation. This review aims to provide an overview of the basic and clinical pharmacology of remimazolam and to compare it with midazolam and propofol.
Topics: Anesthesia, General; Anesthetics, Intravenous; Benzodiazepines; Double-Blind Method; Humans; Hypnotics and Sedatives; Midazolam; Propofol
PubMed: 35585830
DOI: 10.4097/kja.22297 -
Viruses Nov 2022The immune system deploys a complex network of cells and signaling pathways to protect host integrity against exogenous threats, including measles virus (MeV). However,... (Review)
Review
The immune system deploys a complex network of cells and signaling pathways to protect host integrity against exogenous threats, including measles virus (MeV). However, throughout its evolutionary path, MeV developed various mechanisms to disrupt and evade immune responses. Despite an available vaccine, MeV remains an important re-emerging pathogen with a continuous increase in prevalence worldwide during the last decade. Considerable knowledge has been accumulated regarding MeV interactions with the innate immune system through two antagonistic aspects: recognition of the virus by cellular sensors and viral ability to inhibit the induction of the interferon cascade. Indeed, while the host could use several innate adaptors to sense MeV infection, the virus is adapted to unsettle defenses by obstructing host cell signaling pathways. Recent works have highlighted a novel aspect of innate immune response directed against MeV unexpectedly involving DNA-related sensing through activation of the cGAS/STING axis, even in the absence of any viral DNA intermediate. In addition, while MeV infection most often causes a mild disease and triggers a lifelong immunity, its tropism for invariant T-cells and memory T and B-cells provokes the elimination of one primary shield and the pre-existing immunity against previously encountered pathogens, known as "immune amnesia".
Topics: Humans; Immune Evasion; Immunity, Innate; Interferons; Measles; Measles virus; Signal Transduction
PubMed: 36560645
DOI: 10.3390/v14122641 -
ELife Jun 2020Deep inside the temporal lobe of the brain, the hippocampus has a central role in our ability to remember, imagine and dream.
Deep inside the temporal lobe of the brain, the hippocampus has a central role in our ability to remember, imagine and dream.
Topics: Brain; Dreams; Hippocampus; Mental Recall
PubMed: 32508304
DOI: 10.7554/eLife.58874 -
American Family Physician Jan 2022Transient global amnesia (TGA) is a clinical syndrome characterized by anterograde amnesia, mild retrograde amnesia, and confusion up to 24 hours. Most commonly seen in...
Transient global amnesia (TGA) is a clinical syndrome characterized by anterograde amnesia, mild retrograde amnesia, and confusion up to 24 hours. Most commonly seen in patients older than 50 years, TGA results from the temporary impairment of short-term memory formation. Clinically, patients have time disorientation and often ask repeated questions regarding the day's events. Vomiting, headache, blurry vision, dizziness, and nausea may be present. A physically or psychologically stressful precipitating event, such as emotional stress, significant physical exertion, exposure to extreme temperatures, high-altitude conditions, Valsalva maneuver, acute illness, or sexual intercourse, is often the cause. The pathophysiology of TGA is not well understood but may be related to impaired venous drainage of the hippocampus. The diagnosis is primarily clinical, but recent studies suggest that magnetic resonance imaging may be helpful. TGA is self-limited and resolves within 24 hours. There is no established treatment for episodes. The lifetime recurrence rate is 2.9% to 23.8%. Recent evidence suggests an association between TGA and migraine headaches as well as takotsubo cardiomyopathy. No apparent increased risk of cerebrovascular events occurs in patients who have had an episode of TGA. There is conflicting evidence as to whether an episode of TGA predisposes to future seizures or dementia.
Topics: Adult; Amnesia, Transient Global; Coitus; Confusion; Female; Hippocampus; Humans; Magnetic Resonance Imaging; Male; Middle Aged; Migraine Disorders; Physical Exertion; Risk Factors; Stress, Psychological; Takotsubo Cardiomyopathy; Time Factors
PubMed: 35029951
DOI: No ID Found -
Cureus Nov 2021Opioid-associated amnestic syndrome (OAS) is a relatively new condition that is associated with opioid abuse and has increased in prevalence since the notable rise in...
Opioid-associated amnestic syndrome (OAS) is a relatively new condition that is associated with opioid abuse and has increased in prevalence since the notable rise in opioid-related deaths and opioid-related hospitalizations of the opioid crisis. Patients often present with acute anterograde amnesia and current opioid abuse, most commonly fentanyl. OAS is frequently diagnosed when other potentially infectious or metabolic conditions such as encephalitis and seizures are ruled out, as these conditions can also present similarly to OAS. This case highlights the signs, symptoms, and hallmark characteristics of OAS, including bilateral hippocampal edema and anterograde amnesia.
PubMed: 34877229
DOI: 10.7759/cureus.20056 -
Brain, Behavior, and Immunity Aug 2019(Background): Alzheimer's disease (AD), clinically characterized by the progressive neurodegenerative condition and cognitive impairment, is one of the main causes of...
OBJECTIVE
(Background): Alzheimer's disease (AD), clinically characterized by the progressive neurodegenerative condition and cognitive impairment, is one of the main causes of disability in elder people worldwide. Recently, several animal studies indicated that the 'gut-brain' axis might contribute to the amyloid deposition of AD. However, data about gut dysbiosis in human AD remains scarce in the literature, especially including the whole process of AD. In this prospective and cross-sectional study, we aimed at identifying differences in microbiome between patients with AD (Pre-onset stage amnestic mild cognitive impairment, aMCI; and AD) and the normal cognition healthy controls (HC). Additionally, the potential association between IM and clinical characteristics of AD was evaluated.
METHODS
A total of 97 subjects (33 AD, 32 aMCI, and 32 HC) were recruited in the study. The composition of gut bacterial communities was determined by 16S ribosomal RNA Miseq sequencing. In addition, Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) was used to predict function shift of intestinal microbiota. The Mini-Mental State Examination (MMSE), Montreal Cognitive Assessment (MoCA) or Clinical Dementia Rating (CDR) scores were used to evaluate the severity of cognitive impairment in patients.
RESULTS
The fecal microbial diversity was decreased in AD patients compared with aMCI patients and HC. And the microbial composition was distinct among aMCI, AD and healthy control groups. Among bacterial taxa, the proportion of phylum Firmicutes was significantly reduced (P = 0.008), whereas Proteobacteria (P = 0.024) was highly enriched in the AD compared with HC. In addition, similar alterations were observed at the order, class and family levels of these two phyla. And Gammaproteobacteria, Enterobacteriales and Enterobacteriaceae showed a progressive enriched prevalence from HC to aMCI and AD patients. Further, a significant correlation was observed between the clinical severity scores of AD patients and the abundance of altered microbiomes. Moreover, the KEGG results showed the increased modules related to glycan biosynthesis and metabolism in AD and aMCI patients and decreased pathways related to immune system in AD patients. Importantly, the discriminating models based on predominant microbiota could effectively distinguish aMCI and AD from HC (AUC = 0.890, 0.940, respectively), and also AD from aMCI (AUC = 0.925). Notably, the models based on the abundance of family Enterobacteriaceae could distinguish AD from both aMCI (AUC = 0.688) and HC (AUC = 0.698).
CONCLUSIONS
Distinct microbial communities, especially enriched Enterobacteriaceae, were associated with patients with AD when compared with predementia stage aMCI and healthy subjects. These novel findings will give new clues to understand the disease and provide new therapeutic target for intervention or a marker for this disease.
Topics: Aged; Aged, 80 and over; Alzheimer Disease; Amnesia; Area Under Curve; Asian People; Biomarkers; Brain; China; Cognition; Cognitive Dysfunction; Cohort Studies; Cross-Sectional Studies; Feces; Female; Gastrointestinal Microbiome; Humans; Male; Neuropsychological Tests; Prospective Studies; RNA, Ribosomal, 16S
PubMed: 31063846
DOI: 10.1016/j.bbi.2019.05.008 -
Stroke and Vascular Neurology Apr 2022
Topics: Amnesia, Transient Global; Humans; Ischemic Attack, Transient; Stroke
PubMed: 34750283
DOI: 10.1136/svn-2021-001384