The CA3 Region of the Hippocampus: How is it? What is it for? How does it do it? PDF Download

Author: Enrico Cherubini
Publisher: Frontiers Media SA
ISBN: 2889196313
Category : Hippocampus (Brain)
Languages : en
Pages : 167

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Book Description
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.

Author: Roger D. Traub
Publisher: Cambridge University Press
ISBN: 0521364817
Category : Medical
Languages : en
Pages : 306

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Book Description
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.

Author: Helen E. Scharfman
Publisher: Elsevier
ISBN: 0080551750
Category : Science
Languages : en
Pages : 841

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Book Description
The dentate gyrus is a part of the brain that has been a topic of intense interest since the beginning of neuroscience, and pioneering studies from the distant and recent past attest to this. One of the reasons for such interest is that this structure provides some of the most remarkable examples of plasticity within the nervous system. In addition, it is critical to normal cognitive function, although exactly how and when is still a question that eludes answers. Furthermore, abnormalities within the dentate gyrus appear to play a role in diverse clinical conditions, from depression to epilepsy and traumatic brain injury. The primary goal of this book is to provide a context, or background, upon which the detailed knowledge of the current era can be appreciated. A series of overviews are provided to clarify essentials related to structural organization and development, cellular components, neurotransmitters and neuromodulators, plasticity, and clinical relevance. * Covers the topic comprehensively from anatomy to cellular and systems perspectives* Includes basic research and addresses translational implications, so it will be useful to both researchers in the laboratory and clinicians who conduct experiments in humans* Chapters provide fundamentals, but also details and ample references for further review of the topic

Author: Per Andersen
Publisher: Oxford University Press
ISBN: 9780195100273
Category : Medical
Languages : en
Pages : 892

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Book Description
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.

Author: Gordon M. Shepherd
Publisher: Oxford University Press
ISBN: 0190636114
Category : Medical
Languages : en
Pages : 625

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Book Description
In order to focus on principles, each chapter in this work is brief, organized around 1-3 wiring diagrams of the key circuits, with several pages of text that distil the functional significance of each microcircuit

Author: Jerome Engel
Publisher: Lippincott Williams & Wilkins
ISBN: 9780781757775
Category : Medical
Languages : en
Pages : 1272

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Book Description
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.

Author: Thorsten Bartsch
Publisher: OUP Oxford
ISBN: 0191628964
Category : Medical
Languages : en
Pages : 329

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Book Description
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.

Author: Peter Jonas
Publisher: Frontiers Media SA
ISBN: 288919387X
Category : Neurosciences. Biological psychiatry. Neuropsychiatry
Languages : en
Pages : 134

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Book Description
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.

Author: Ahmed A. Moustafa
Publisher: John Wiley & Sons
ISBN: 1119159075
Category : Psychology
Languages : en
Pages : 588

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Book Description
A comprehensive Introduction to the world of brain and behavior computational models This book provides a broad collection of articles covering different aspects of computational modeling efforts in psychology and neuroscience. Specifically, it discusses models that span different brain regions (hippocampus, amygdala, basal ganglia, visual cortex), different species (humans, rats, fruit flies), and different modeling methods (neural network, Bayesian, reinforcement learning, data fitting, and Hodgkin-Huxley models, among others). Computational Models of Brain and Behavior is divided into four sections: (a) Models of brain disorders; (b) Neural models of behavioral processes; (c) Models of neural processes, brain regions and neurotransmitters, and (d) Neural modeling approaches. It provides in-depth coverage of models of psychiatric disorders, including depression, posttraumatic stress disorder (PTSD), schizophrenia, and dyslexia; models of neurological disorders, including Alzheimer’s disease, Parkinson’s disease, and epilepsy; early sensory and perceptual processes; models of olfaction; higher/systems level models and low-level models; Pavlovian and instrumental conditioning; linking information theory to neurobiology; and more. Covers computational approximations to intellectual disability in down syndrome Discusses computational models of pharmacological and immunological treatment in Alzheimer's disease Examines neural circuit models of serotonergic system (from microcircuits to cognition) Educates on information theory, memory, prediction, and timing in associative learning Computational Models of Brain and Behavior is written for advanced undergraduate, Master's and PhD-level students—as well as researchers involved in computational neuroscience modeling research.

Author: Gordon L. Fain
Publisher: Harvard University Press
ISBN: 0674599217
Category : Medical
Languages : en
Pages : 766

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Book Description
Molecular and Cellular Physiology of Neurons, Second Edition is a comprehensive, up-to-date introduction to essential concepts of cellular neuroscience. Emphasizing experimental approaches and recent discoveries, it provides an in-depth look at the structure and function of nerve cells, from protein receptors and synapses to the biochemical processes that drive the mammalian nervous system. Starting with the basics of electrical current flow across cell membranes, Gordon Fain covers voltage gating and receptor activation in the context of channel diversity, excitatory and inhibitory synaptic transmission, neuromodulation, and sensory transduction. Emphasizing long-term processes of synaptic potentiation and depression involved in memory, consciousness, and attention, he demonstrates how cells produce neural signals and regulate signal flow to enhance or impede cell-to-cell communication. Fain also addresses the relation of molecular and cellular mechanisms to evolving theories of neurological disease and addiction. Enhanced by more than two hundred illustrations, Molecular and Cellular Physiology of Neurons, Second Edition is intended for anyone who seeks to understand the fundamentals of nerve cell function, including undergraduate and graduate students in neuroscience, students of bioengineering and cognitive science, and practicing neuroscientists who want to deepen their knowledge of recent discoveries in molecular and cellular neurophysiology.