Download or read book The CA3 Region of the Hippocampus How is it What is it for How does it do it written by Enrico Cherubini and published by Frontiers Media SA. This book was released on 2015-08-19 with total page 167 pages. Available in PDF, EPUB and Kindle. Book excerpt: The CA3 hippocampal region receives information from the entorhinal cortex either directly from the perforant path or indirectly from the dentate gyrus via the mossy fibers (MFs). According to their specific targets (principal/mossy cells or interneurons), MFs terminate with large boutons or small filopodial extensions, respectively. MF-CA3 synapses are characterized by a low probability of release and pronounced frequency-dependent facilitation. In addition MF terminals are endowed with mGluRs that regulate their own release. We will describe the intrinsic membrane properties of pyramidal cells, which can sometimes fire in bursts, together with the geometry of their dendritic arborization. The single layer of pyramidal cells is quite distinct from the six-layered neocortical arrangement. The resulting aligned dendrites provides the substrate for laminated excitatory inputs. They also underlie a precise, diversity of inhibitory control which we will also describe in detail. The CA3 region has an especially rich internal connectivity, with recurrent excitatory and inhibitory loops. In recent years both in vivo and in vitro studies have allowed to better understand functional properties of the CA3 auto-associative network and its role in information processing. This circuit is implicated in encoding spatial representations and episodic memories. It generates physiological population synchronies, including gamma, theta and sharp-waves that are presumed to associate firing in selected assemblies of cells in different behavioral conditions. The CA3 region is susceptible to neurodegeneration during aging and after stresses such as infection or injury. Loss of some CA3 neurones has striking effects on mossy fiber inputs and can facilitate the generation of pathologic synchrony within the CA3 micro-circuit. The aim of this special topic is to bring together experts on the cellular and molecular mechanisms regulating the wiring properties of the CA3 hippocampal microcircuit in both physiological and pathological conditions, synaptic plasticity, behavior and cognition.We will particularly emphasize the dual glutamatergic and GABAergic phenotype of MF-CA3 synapses at early developmental stages and the steps that regulate the integration of newly generated neurons into the adult dentate gyrus-CA3 circuit.
Download or read book Structure function and plasticity of hippocampal dentate gyrus microcircuits written by Peter Jonas and published by Frontiers Media SA. This book was released on 2015-02-13 with total page 134 pages. Available in PDF, EPUB and Kindle. Book excerpt: The hippocampus mediates several higher brain functions, such as learning, memory, and spatial coding. The input region of the hippocampus, the dentate gyrus, plays a critical role in these processes. Several lines of evidence suggest that the dentate gyrus acts as a preprocessor of incoming information, preparing it for subsequent processing in CA3. For example, the dentate gyrus converts input from the entorhinal cortex, where cells have multiple spatial fields, into the spatially more specific place cell activity characteristic of the CA3 region. Furthermore, the dentate gyrus is involved in pattern separation, transforming relatively similar input patterns into substantially different output patterns. Finally, the dentate gyrus produces a very sparse coding scheme in which only a very small fraction of neurons are active at any one time. How are these unique functions implemented at the level of cells and synapses? Dentate gyrus granule cells receive excitatory neuron input from the entorhinal cortex and send excitatory output to the hippocampal CA3 region via the mossy fibers. Furthermore, several types of GABAergic interneurons are present in this region, providing inhibitory control over granule cell activity via feedback and feedforward inhibition. Additionally, hilar mossy cells mediate an excitatory loop, receiving powerful input from a small number of granule cells and providing highly distributed excitatory output to a large number of granule cells. Finally, the dentate gyrus is one of the few brain regions exhibiting adult neurogenesis. Thus, new neurons are generated and functionally integrated throughout life. How these specific cellular and synaptic properties contribute to higher brain functions remains unclear. One way to understand these properties of the dentate gyrus is to try to integrate experimental data into models, following the famous Hopfield quote: “Build it, and you understand it.” However, when trying this, one faces two major challenges. First, hard quantitative data about cellular properties, structural connectivity, and functional properties of synapses are lacking. Second, the number of individual neurons and synapses to be represented in the model is huge. For example, the dentate gyrus contains ~1 million granule cells in rodents, and ~10 million in humans. Thus, full scale models will be complex and computationally demanding. In this Frontiers Research Topic, we collect important information about cells, synapses, and microcircuit elements of the dentate gyrus. We have put together a combination of original research articles, review articles, and a methods article. We hope that the collected information will be useful for both experimentalists and modelers. We also hope that the papers will be interesting beyond the small world of “dentology,” i.e., for scientists working on other brain areas. Ideally, the dentate gyrus may serve as a blueprint, helping neuroscientists to define strategies to analyze network organization of other brain regions.
Download or read book The Hippocampus Book written by Per Andersen and published by Oxford University Press. This book was released on 2007 with total page 892 pages. Available in PDF, EPUB and Kindle. Book excerpt: The hippocampus is one of a group of remarkable structures embedded within the brain's medial temporal lobe. Long known to be important for memory, it has been a prime focus of neuroscience research for many years. The Hippocampus Book promises to facilitate developments in the field in a major way by bringing together, for the first time, contributions by leading international scientists knowledgeable about hippocampal anatomy, physiology, and function. This authoritative volume offers the most comprehensive, up-to-date account of what the hippocampus does, how it does it, and what happens when things go wrong. At the same time, it illustrates how research focusing on this single brain structure has revealed principles of wider generality for the whole brain in relation to anatomical connectivity, synaptic plasticity, cognition and behavior, and computational algorithms. Well-organized in its presentation of both theory and experimental data, this peerless work vividly illustrates the astonishing progress that has been made in unraveling the workings of the brain. The Hippocampus Book is destined to take a central place on every neuroscientist's bookshelf.
Download or read book Epilepsy written by Jerome Engel and published by Lippincott Williams & Wilkins. This book was released on 2007-09-28 with total page 1272 pages. Available in PDF, EPUB and Kindle. Book excerpt: Written and edited by world-renowned authorities, this three-volume work is, to quote a reviewer, "the definitive textbook about seizures and epilepsy". This Second Edition is thoroughly updated and gives you a complete print and multimedia package: the three-volume set plus access to an integrated content Website. More than 300 chapters cover the spectrum of biology, physiology, and clinical information, from molecular biology to public health concerns in developing countries. Included are detailed discussions of seizure types and epilepsy syndromes; relationships between physiology and clinical events; psychiatric and medical comorbidity; conditions that could be mistaken for epilepsy; and an increasing range of pharmacologic, surgical, and alternative therapies, including vagus nerve stimulation and deep brain stimulation. This edition describes many new antiepileptic drugs, major advances in surgical treatment, and state-of-the-art neuroimaging, EEG, and other technologies for diagnosis and seizure prediction. A companion Website offers instant access to the complete, fully searchable text, plus an image bank of additional figures, video footage, and annual updates to selected chapters.
Download or read book Neuronal Networks of the Hippocampus written by Roger D. Traub and published by Cambridge University Press. This book was released on 1991-05-31 with total page 306 pages. Available in PDF, EPUB and Kindle. Book excerpt: The questions of how a large population of neurons in the brain functions, how synchronized firing of neurons is achieved, and what factors regulate how many and which neurons fire under different conditions form the central theme of this book. Important neurological techniques for the physiological reconstruction of a large biological neural network are presented.
Download or read book The Hippocampus written by Philippe Taupin and published by Nova Publishers. This book was released on 2007 with total page 156 pages. Available in PDF, EPUB and Kindle. Book excerpt: The hippocampus , the Greek word for seahorse, is one of the most fascinating and intriguing regions of the mammalian brain. It is a bilateral incurved seahorse-shaped structure of the cerebral cortex. The hippocampus has a highly distinctive morphology. It is composed of two regions, the dentate gyrus (DG) and the Cornu Ammonis (CA). The nerve cells of the main layer of the DG and CA regions, the granule cells and pyramidal cells respectively, are organised in a tri-synaptic lamellaire circuit. The granule and pyramidal cells are glutamatergic excitatory. The granule cells elicit unique histological, biochemical, developmental, physio- and pathological features. The hippocampus is also an area of the brain that elicits a high degree of plasticity, like synaptic and phenotypic plasticity. It is also one of the few regions of the brain where neurogenesis, the generation of new nerve cells, occurs throughout adulthood. The hippocampus is involved in physio-and pathological processes, like learning and memory.
Download or read book A Study of Long term Potentiation in the CA3 Region of the Hippocampus written by Karin Jane Feasey and published by . This book was released on 1986 with total page 432 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Postnatal Development of the Human Hippocampal Formation written by Ricardo Insausti and published by Springer Science & Business Media. This book was released on 2010 with total page 99 pages. Available in PDF, EPUB and Kindle. Book excerpt: The postnatal development of the human hippocampal formation (HF) is subject of increasing interest due to its implication in important pathologies that hamper the normal development of children. In this work, the authors present a glimpse of the main events that constitute important milestones in the development and shaping of some of the most important psychological capabilities such as autobiographical memory. Although they examined some cases in the last trimester of gestation, their description starts at birth, around 40 gestational weeks. Serial sections with thionin for Nissl analysis revealed that all fields of the HF were present and identifiable at birth. However, the relative growth of the cortical mantle was much higher relative to the HF. The main structural changes took place during the first postnatal year, in particular in the dentate gyrus and in the entorhinal cortex. At subsequent ages, a growth in size was noted in all components of the HF. This growth was more evident at the body and tail of the hippocampus, as evidenced by measurements of the neuroanatomical series. In addition, the authors examined in some cases the MRI appearance of the HF at different postnatal ages obtained by post-mortem imaging. MRI neuroanatomical series provided anatomically identified landmarks useful for the MRI identification of different components of the HF during postnatal development.
Download or read book Alterations to Synaptic Function and Connectivity in Area CA3 of the Hippocampus in Mouse Models of Mental Retardation written by Ricardo Andres Valenzuela and published by Stanford University. This book was released on 2011 with total page 165 pages. Available in PDF, EPUB and Kindle. Book excerpt: Down Syndrome and Fragile X Syndrome are disorders of mental retardation that are characterized by cognitive impairments and changes to other physical characteristics. A goal in the study of these diseases has been to understand the mechanisms that underlie the cognitive impairments present in these two disorders of mental retardation. A great deal of effort has been made to study synaptic function and structure in these disorders of mental retardation in order to determine whether there are any alterations present. Alterations to synaptic structure and function present during these disorders may give insight to the neural basis of the cognitive impairments that are characteristic of this disorder of mental retardation. An area of the brain that may be affected by these disorders is the hippocampus. This area of the brain has been extensively studied for its role in memory and alterations to synaptic function and structure may underlie some of the memory deficits present in these disorders of mental retardation. Both Down Syndrome patients and Fragile X Syndrome patients have deficits in their performance on memory tests. Down Syndrome patients also have a reduction in the number of neurons present in the hippocampus (Carlesimo et al., 1997). Fragile X Syndrome patients had structural abnormalities in the hippocampus including an enlargement of ventricular spaces (Jakala et al., 1997). Synaptic function and structure in the hippocampus of mouse models of Down Syndrome and Fragile X Syndrome were studied in order to determine this region of the brain was affected. Electrophysiology recordings in area CA3 of the hippocampus of the Ts65Dn Down Syndrome mouse model indicated there were disruptions to synaptic connectivity, decreases in excitatory and inhibitory synaptic transmission, and also a reduction in intrinsic interneuron activity. Imaging studies of CA3 in the Ts65Dn mouse did not show alterations to the number of synapses or structure of synapses suggesting that the alterations found with electrophysiology recordings are the result of functional changes to synapses. Electrophysiology study of the hippocampus in mouse models of Fragile X Syndrome has shown that inhibitory function was generally intact but that excitatory axons from neurons that lacked the Fragile X Mental Retardation Protein (FMRP) were less competitive at forming synapses in a mosaic expression system of the Fmr1 gene the lack of which causes the disease. These studies indicate that alterations to synaptic structure and function are present in the hippocampus of these mouse models of mental retardation. The differences however, were not the same in Down Syndrome and Fragile X Syndrome mouse models. Nonetheless, it is possible that the changes to synaptic function found in both of these mouse models leads to altered network function in the hippocampus which may, in turn, be the underlying cause of the memory deficits present in these disorders of mental retardation. The data presented in these studies indicate that the study of these mouse models of mental retardation can give insight to alterations caused by these disorders of mental retardation which may also lead to the development of new treatments.
Download or read book The Dentate Gyrus written by Helen E. Scharfman and published by Elsevier Science Serials. This book was released on 2007 with total page 787 pages. Available in PDF, EPUB and Kindle. Book excerpt: A compilation of the fundamentals of the dentate gyrus, an area of the brain of intense scientific interest due to its capacity for plasticity.
Download or read book Hippocampus written by Douglas D. Burman and published by BoD – Books on Demand. This book was released on 2023-07-19 with total page 210 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ever since side effects from bilateral hippocampectomy were identified in Henry Molaison (patient “HM”) during the 1950s, a critical role of the hippocampus has been recognized in the formation of declarative episodic memories. Other cognitive functions have since been proposed, such as a role in navigation, but memory has often been suggested to explain hippocampal involvement. Proving a distinct functional role in cognition is difficult, as memory can be implicated in most cognitive activities. Even when a behavior relies on memory, however, the functionality of the hippocampus extends far beyond, especially evident during activities requiring interactions between cognitive systems. Relational memory is supported by hippocampal connections with widespread regions of the cortex; these interconnections also play a fundamental role in children’s writing abilities and expertise in musical performance. Besides enhancing individual lives, such activities can play a vital role in sustaining cultural values across generations. Interactions with the environment that do not directly depend on mnemonic activity can affect plasticity in hippocampal connections, modified through natural chemicals, pharmacological drugs, and non-pharmacological behaviors. Navigational properties of the hippocampal system are not limited to memory, containing the same navigational elements as our Global Positional System (GPS). Even cognitive deficits arising from hippocampal lesions in “HM” were not limited to memory, as they included deficits in understanding cognitive relationships available in visual scenes, novel sentence contexts, and humorous situations. This book shows an expansive role of the hippocampus in cognition that goes beyond its recognized role in generating new episodic memories.
Download or read book Contemporary Physics written by Jamil Aslam and published by World Scientific. This book was released on 2008 with total page 262 pages. Available in PDF, EPUB and Kindle. Book excerpt: This proceedings volume reviews the current status of research in major frontline areas of physics. With contributions from leading physicists, the areas of research covered in the various papers include condensed matter physics, particle physics, quantum optics, quantum computing and laser physics, nanosciences, synchrotron radiation, relativity, astrophysics and cosmology, and plasma physics.
Download or read book The Hippocampus Book written by Richard Morris and published by Oxford University Press. This book was released on 2024-11 with total page 1033 pages. Available in PDF, EPUB and Kindle. Book excerpt: Known to be important for memory, the hippocampus has long been a prime focus for neuroscience research. This second edition of The Hippocampus Book is written by experts in a wide range of disciplines, with new chapters summarizing how disorders of hippocampal function contribute to neurological and psychiatric conditions. The editors draw on their experience in hippocampal anatomy, physiology, cognitive neuroscience and disease pathobiology to weave together an authoritative book which will interest those working in numerous neuroscientific disciplines.
Download or read book Clinical Neuroimmunology written by Jack P. Antel and published by . This book was released on 2005 with total page 467 pages. Available in PDF, EPUB and Kindle. Book excerpt: Clinical Neurimmunology is the major reference text in the field, providing broad and comprehensive coverage of the interaction between the nervous and immune systems in both normal and diseased states. Understanding this interaction is fundamental to developing therapeutic approaches to disease and injury of the nervous system that are currently only marginally amenable to therapy. Neuroimmunology is a well-recognised and growing specialty world wide, both at the basic science and clinical level. It is a fast moving field and this is the most up to date text available. Chapters are dedicated to the role of the immune system in disorders affecting both the central and peripheral nervous systems, including important neurodegenerative diseases (such as multiple sclerosis and HIV-related neural degeneration) which cause life-long disability. Extensive coverage is given to a whole array of immune-directed therapies. The book has a strong international team of well respected, high profile editors and authors. The first edition published to extensive and positive reviews and has established itself as the principal reference source in the field. This second edition summarizes recent advances in clinical neuroimmunology in a comprehensive and unbiased way.
Download or read book The Clinical Neurobiology of the Hippocampus written by Thorsten Bartsch and published by Oxford University Press. This book was released on 2012-07-26 with total page 336 pages. Available in PDF, EPUB and Kindle. Book excerpt: The hippocampus is one of the most studied structures in the human brain and plays a pivotal role in human memory function. Its recognized function is reflected by the presence of an extensive body of neurophysiological, neuropsychological, anatomical and neurocomputational literature that presents basic mechanisms, theoretical models and psychological concepts. However, in the rapidly growing field of hippocampal research, the clinical aspects of diseases that affect the hippocampus are greatly under-represented in current literature, and clinical approaches and concepts are scattered throughout various clinical and basic scientific disciplines. The Clinical Neurobiology of the Hippocampus explores clinical approaches to the range of diseases that affect the hippocampus. It brings together and reviews the common methods, clinical findings, concepts, mechanisms and, where applicable, therapeutic strategies for these clinical approaches. The clinical spectrum of hippocampal dysfunction encompasses a wide range of neurological, behavioural and psychiatric symptoms and surpasses the ability to encode, store and retrieve information. The relevance of hippocampal involvement in clinical diseases goes beyond mere neuropsychological deficits and includes psychopathological states in various conditions, such as acute amnesic syndromes, Alzheimer's disease, temporal lobe epilepsy (TLE), sleep, stroke medicine, limbic encephalitis, neurodevelopmental disorders, stress- and trauma-related disorders, depression, and schizophrenia. The first part of the book covers the basic and integrative features of the hippocampus, such as the anatomy and imaging of this structure, and the basic mechanisms of hippocampal function, including the principles of hippocampus-dependent memory processing in amnesia and sleep, the mechanisms of vulnerability and adult neurogenesis as well as the effects of stress. The second part covers the various clinical manifestations in which the hippocampus is involved and in which the preceding basic mechanisms are reflected. Bringing together a broad team of experts on the basic and clinical aspects of the hippocampus, the book provides an integrative view of the hippocampus. It is invaluable for neurologists, neuroscientists, and psychiatrists, and will stimulate interdisciplinary discussions in clinical neuroscience.
Download or read book Neurobiology written by Georg F. Striedter and published by Oxford University Press. This book was released on 2016 with total page 644 pages. Available in PDF, EPUB and Kindle. Book excerpt: Focusing on the problems that brains help organisms solve, Neurobiology: A Functional Approach asks not only how the nervous system works but also why it works as it does. This text introduces readers to neurobiology through an evolutionary, organismal, and experimental perspective. With a strong emphasis on neural circuits and systems, it bridges the gap between the cellular and molecular end and the cognitive end of the neuroscience spectrum, allowing students to grasp the full breadth of the subject. Neurobiology covers not only what neuroscientists have learned about the brain in terms of facts and ideas, but also how they have learned it through key experiments.
Download or read book Traumatic Brain Injury written by Mark J. Ashley and published by CRC Press. This book was released on 2016-04-19 with total page 1082 pages. Available in PDF, EPUB and Kindle. Book excerpt: Since the bestselling second edition was published almost a decade ago, the field of brain injury treatment has undergone tremendous change, largely impacting access to treatment. But, while the healthcare marketplace has evolved, the needs of brain injury victims remain the same. With updated and expanded clinical coverage, Traumatic Brain Injury: Rehabilitation, Treatment, and Case Management, Third Edition delineates a broad spectrum of advanced theoretical clinical constructs and detailed diagnostic and treatment interventions for traumatic brain injury. Details Specific Diagnostic and Treatment Approaches for Nearly All Aspects of Dysfunction Observed Following Brain Injury With contributions from more than 50 authorities in both academia and industry, this highly respected text stands apart as a clinical guide to rehabilitative treatment of persons with traumatic brain injury following the acute phase of treatment. It provides a concise source of information about the scientific and therapeutic realms involved in the rehabilitation of a person with traumatic brain injury, specifically as they relate to persistent deficits. The book also details long-term consequences of brain injury and effective approaches to vocational rehabilitation and case management. Widening coverage from the previous edition, this book includes details on: Metabolic and bioenergetic factors in brain injury Neuroendocrine dysfunction following brain injury Blast injury Ethical issues in treatment of brain injury Neuropharmacological and neuropsychological interventions following brain injury Interventions for the minimally conscious patient Dietary and exercise considerations after brain injury Traumatic Brain Injury: Rehabilitation, Treatment, and Case Management, Third Edition is a complete source of pharmacological, anatomical, and physiological information for basic therapeutic rationales that are often not well understood in the field. It is an ideal reference for both new and experienced clinicians.
