Neuroscience
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Long-term potentiation (LTP) is a widely studied phenomenon since the underlying molecular mechanisms are widely believed to be critical for learning and memory and their dysregulation has been implicated in many brain disorders affecting cognitive functions. Central to the induction of LTP, in most pathways that have been studied in the mammalian CNS, is the N-methyl-D-aspartate receptor (NMDAR). Philippe Ascher discovered that the NMDAR is subject to a rapid, highly voltage-dependent block by Mg2+. ⋯ It explains how this unusual molecular mechanism underlies the Hebbian nature of synaptic plasticity and the hallmark features of NMDAR-LTP (input specificity, cooperativity and associativity). Then the role of the Mg2+ block of NMDARs is discussed in the context of memory and dementia. In particular, the idea that alterations in the voltage-dependent block of the NMDAR is a component of cognitive decline during normal ageing and neurodegenerative disorders, such as Alzheimer's disease, is discussed.
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From the start of pregnancy, mother and child induce reciprocal neurobiological changes in the brain that will prove critical for neurodevelopment and survival of both. Molecular communication between mother and fetus is constantly active and persists even after the fetus starts to synthesize its hormones in late gestation. Intriguingly, some mother and fetus exchange cells remain in the other's brain and body with long-lasting effects and memories that do not follow the laws of classical genetics but involve complex epigenetic mechanisms. ⋯ The interplay between these two "limbo" states allows for an easier transition to the subsequent phases of development. In this review, we will trace mother's and child's path from pregnancy to the months following birth and, in particular, unravel i) the key features of pregnancy and brain development and the reciprocal influences; ii) how a transitory pattern of functioning characterize mother and child, moving them toward more flexible and evolved forms; and iii) how mother and fetus act during childbirth to promote neuroprotection, pain reduction, and neurophysiological changes. Therefore, this review covers a wide range of topics, integrating neuroanatomical, neurological, biochemical, neurophysiological, and psychological studies in a meaningful way, trying to integrate them in a holistic view of the mother-child interface that is usually neglected.
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Chronic pain is prevalent among aging adults. Epidemiologic evidence has demonstrated that individuals with chronic pain have accelerated memory decline and increased probability of dementia. ⋯ We validate this with multiple independent data sets and identify cortical microglia as a likely mechanism by which chronic pain can increase dementia risk. Our analyses support the molecular hypothesis for the role of chronic pain in cognitive decline and identifies several potential therapeutic targets.
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Meta Analysis
Mendelian randomization in Alzheimer's disease and mild cognitive impairment: Hippocampal volume associations.
This study investigates the association between cognitive dysfunction and hippocampal volumes in Alzheimer's Disease (AD) and Mild Cognitive Impairment (MCI) using Mendelian randomization. A meta-analysis of 503 healthy controls, 562 MCI patients, and 389 CE patients revealed significant reductions in hippocampal and subregion volumes in MCI and AD compared to controls. While various subregions showed volume reductions, no causal relationship between hippocampal volume and AD was established through Mendelian randomization analysis. In conclusion, significant volume reductions were observed in MCI and AD patients, highlighting the complexity of the relationship between hippocampal volume and cognitive impairment.
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Review
Dualism, Materialism, and the relationship between the brain and the mind in experiencing pain.
Characterizing the relationship between the brain and the mind is essential, both for understanding how we experience sensations and for attempts to create machine-based artificial intelligence. Materialists argue that the brain and the mind are both physical/material in nature whereas Cartesian dualists posit that the brain is material, the mind is non-material, and that they are separate. Recent investigations into the mechanisms responsible for pain can resolve this issue. ⋯ The material brain and immaterial mind are therefore separate and we can no longer attribute painfulness solely to the activities of the brain. This is a radical departure from the contemporary view of brain functions and supports Cartesian Dualism. Consequently, consciousness and higher mental functions cannot be duplicated by mimicking the activities of the brain.