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Author: Karin Lundengård
Publisher: Linköping University Electronic Press
ISBN: 9176854418
Category :
Languages : en
Pages : 80
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Book Description
Functional Magnetic Resonance Imaging (fMRI) is a common technique for imaging brain activity in humans. However, the fMRI signal stems from local changes in oxygen level rather than from neuronal excitation. The change in oxygen level is referred to as the Blood Oxygen Level Dependent (BOLD) response, and is connected to neuronal excitation and the BOLD response are connected by the neurovascular coupling. The neurons affect the oxygen metabolism, blood volume and blood flow, and this in turn controls the shape of the BOLD response. This interplay is complex, and therefore fMRI analysis often relies on models. However, none of the previously existing models are based on the intracellular mechanisms of the neurovascular coupling. Systems biology is a relatively new field where mechanistic models are used to integrate data from many different parts of a system in order to holistically analyze and predict system properties. This thesis presents a new framework for analysis of fMRI data, based on mechanistic modelling of the neurovascular coupling, using systems biology methods. Paper I presents the development of the first intracellular signaling model of the neurovascular coupling. Using models, a feed-forward and a feedback hypothesis are tested against each other. The resulting model can mechanistically explain both the initial dip, the main response and the post-peak undershoot of the BOLD response. It is also fitted to estimation data from the visual cortex and validated against variations in frequency and intensity of the stimulus. In Paper II, I present a framework for separating activity from noise by investigating the influence of the astrocytes on the blood vessels via release of vasoactive sub- stances, using observability analysis. This new method can recognize activity in both measured and simulated data, and separate differences in stimulus strength in simulated data. Paper III investigates the effects of the positive allosteric GABA modulator diazepam on working memory in healthy adults. Both positive and negative BOLD was measured during a working memory task, and activation in the cingulate cortex was negatively correlated to the plasma concentration of diazepam. In this area, the BOLD response had decreased below baseline in test subjects with >0.01 mg/L diazepam in the blood. Paper IV expands the model presented in Paper I with a GABA mechanism so that it can describe neuronal inhibition and the negative BOLD response. Sensitization of the GABA receptors by diazepam was added, which enabled the model to explain how changes to the BOLD response described in Paper III could occur without a change in the balance between the GABA and glutamate concentrations. The framework presented herein may serve as the basis for a new method for identification of both brain activity and useful potential biomarkers for brain diseases and disorders, which will bring us a deeper understanding of the functioning of the human brain.
Author: Karin Lundengård
Publisher: Linköping University Electronic Press
ISBN: 9176854418
Category :
Languages : en
Pages : 80
Get Book Here
Book Description
Functional Magnetic Resonance Imaging (fMRI) is a common technique for imaging brain activity in humans. However, the fMRI signal stems from local changes in oxygen level rather than from neuronal excitation. The change in oxygen level is referred to as the Blood Oxygen Level Dependent (BOLD) response, and is connected to neuronal excitation and the BOLD response are connected by the neurovascular coupling. The neurons affect the oxygen metabolism, blood volume and blood flow, and this in turn controls the shape of the BOLD response. This interplay is complex, and therefore fMRI analysis often relies on models. However, none of the previously existing models are based on the intracellular mechanisms of the neurovascular coupling. Systems biology is a relatively new field where mechanistic models are used to integrate data from many different parts of a system in order to holistically analyze and predict system properties. This thesis presents a new framework for analysis of fMRI data, based on mechanistic modelling of the neurovascular coupling, using systems biology methods. Paper I presents the development of the first intracellular signaling model of the neurovascular coupling. Using models, a feed-forward and a feedback hypothesis are tested against each other. The resulting model can mechanistically explain both the initial dip, the main response and the post-peak undershoot of the BOLD response. It is also fitted to estimation data from the visual cortex and validated against variations in frequency and intensity of the stimulus. In Paper II, I present a framework for separating activity from noise by investigating the influence of the astrocytes on the blood vessels via release of vasoactive sub- stances, using observability analysis. This new method can recognize activity in both measured and simulated data, and separate differences in stimulus strength in simulated data. Paper III investigates the effects of the positive allosteric GABA modulator diazepam on working memory in healthy adults. Both positive and negative BOLD was measured during a working memory task, and activation in the cingulate cortex was negatively correlated to the plasma concentration of diazepam. In this area, the BOLD response had decreased below baseline in test subjects with >0.01 mg/L diazepam in the blood. Paper IV expands the model presented in Paper I with a GABA mechanism so that it can describe neuronal inhibition and the negative BOLD response. Sensitization of the GABA receptors by diazepam was added, which enabled the model to explain how changes to the BOLD response described in Paper III could occur without a change in the balance between the GABA and glutamate concentrations. The framework presented herein may serve as the basis for a new method for identification of both brain activity and useful potential biomarkers for brain diseases and disorders, which will bring us a deeper understanding of the functioning of the human brain.
Author: Matt A. Bernstein
Publisher: Elsevier
ISBN: 0080533124
Category : Mathematics
Languages : en
Pages : 1041
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Book Description
Magnetic Resonance Imaging (MRI) is among the most important medical imaging techniques available today. There is an installed base of approximately 15,000 MRI scanners worldwide. Each of these scanners is capable of running many different "pulse sequences", which are governed by physics and engineering principles, and implemented by software programs that control the MRI hardware. To utilize an MRI scanner to the fullest extent, a conceptual understanding of its pulse sequences is crucial. Handbook of MRI Pulse Sequences offers a complete guide that can help the scientists, engineers, clinicians, and technologists in the field of MRI understand and better employ their scanner. - Explains pulse sequences, their components, and the associated image reconstruction methods commonly used in MRI - Provides self-contained sections for individual techniques - Can be used as a quick reference guide or as a resource for deeper study - Includes both non-mathematical and mathematical descriptions - Contains numerous figures, tables, references, and worked example problems
Author: Bozzano G Luisa
Publisher: Elsevier
ISBN: 0323140203
Category : Science
Languages : en
Pages : 510
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Book Description
Mass Action in the Nervous System: Examination of the Neurophysiological Basis of Adaptive Behavior through the EEG focuses on the neural mechanisms and the behavioral significance of the electroencephalogram, with emphasis on observations made on the mammalian olfactory system. Organized into seven chapters, this book begins with a brief nonmathematical review of the concept of the neuron and the interrelations among neurons that lead to the formation of interactive masses. Some chapters follow on the linear properties of neurons and their parts; the ionic hypothesis; the nonlinear input-output relations of neurons in masses expressed in terms of amplitude-dependent coefficients in linear differential equations; and the relations between the states of activity of neurons. Subsequent chapters describe the properties resulting from feedback within neural masses; the effects of the nonlinearities in the input-output relations of neurons on the behavior of masses; and some inferences concerning the mechanisms of neural signal processing at the level of neural masses. The book is a model for an advanced text in neurophysiology, and some understanding is assumed of the elements of the fields of linear analysis, probability, statistics, theory of potential, neuroanatomy, electrophysiology, neuropharmacology, and experimental psychology.
Author: William D. Penny
Publisher: Elsevier
ISBN: 0080466508
Category : Psychology
Languages : en
Pages : 689
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Book Description
In an age where the amount of data collected from brain imaging is increasing constantly, it is of critical importance to analyse those data within an accepted framework to ensure proper integration and comparison of the information collected. This book describes the ideas and procedures that underlie the analysis of signals produced by the brain. The aim is to understand how the brain works, in terms of its functional architecture and dynamics. This book provides the background and methodology for the analysis of all types of brain imaging data, from functional magnetic resonance imaging to magnetoencephalography. Critically, Statistical Parametric Mapping provides a widely accepted conceptual framework which allows treatment of all these different modalities. This rests on an understanding of the brain's functional anatomy and the way that measured signals are caused experimentally. The book takes the reader from the basic concepts underlying the analysis of neuroimaging data to cutting edge approaches that would be difficult to find in any other source. Critically, the material is presented in an incremental way so that the reader can understand the precedents for each new development. This book will be particularly useful to neuroscientists engaged in any form of brain mapping; who have to contend with the real-world problems of data analysis and understanding the techniques they are using. It is primarily a scientific treatment and a didactic introduction to the analysis of brain imaging data. It can be used as both a textbook for students and scientists starting to use the techniques, as well as a reference for practicing neuroscientists. The book also serves as a companion to the software packages that have been developed for brain imaging data analysis. - An essential reference and companion for users of the SPM software - Provides a complete description of the concepts and procedures entailed by the analysis of brain images - Offers full didactic treatment of the basic mathematics behind the analysis of brain imaging data - Stands as a compendium of all the advances in neuroimaging data analysis over the past decade - Adopts an easy to understand and incremental approach that takes the reader from basic statistics to state of the art approaches such as Variational Bayes - Structured treatment of data analysis issues that links different modalities and models - Includes a series of appendices and tutorial-style chapters that makes even the most sophisticated approaches accessible
Author: J. P. Schadé
Publisher:
ISBN: 9780444409522
Category : Brain
Languages : en
Pages : 438
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Book Description
Author: Luca Saba
Publisher: Springer
ISBN: 3319480464
Category : Medical
Languages : en
Pages : 509
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Book Description
Authored by world renowned scientists, this book expertly reviews all the imaging techniques and exciting new methods for the analysis of the pain, including novel tracers, biomarker, metabolomic and gene-array profiling, together with cellular, genetic, and molecular approaches. Recent advances in human brain imaging techniques have allowed a better understand of the functional connectivity in pain pathways, as well as the functional and anatomical alterations that occur in chronic pain patients. Modern imaging techniques have permitted rapid progress in the understanding of networks in the brain related to pain processing and those related to different types of pain modulation. Neuroimaging of Pain is designed to be a valuable resource for radiologists, neuroradiologists, neurologists and neuroscientists, working in hospitals and universities from junior trainees to consultants.
Author: Dajiang Zhu
Publisher: Frontiers Media SA
ISBN: 2832547575
Category : Science
Languages : en
Pages : 230
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Book Description
Brain mapping is dedicated to using brain imaging techniques such as MRI, CT, PET, EEG, and fNIRS to understand the brain anatomy, structure, and function, and how it contributes to cognition, behavior, and deficits of brain diseases. Recently, machine learning is in a stage of rapid development, and various new technologies are continuously introduced into the field, from traditional approaches
Author: Kamil Uludag
Publisher: Springer
ISBN: 1489975918
Category : Medical
Languages : en
Pages : 926
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Book Description
This volume explores the revolutionary fMRI field from basic principles to state-of-the-art research. It covers a broad spectrum of topics, including the history of fMRI's development using endogenous MR blood contrast, neurovascular coupling, pulse sequences for fMRI, quantitative fMRI; fMRI of the visual system, auditory cortex, and sensorimotor system; genetic imaging using fMRI, multimodal neuroimaging, brain bioenergetics and function and molecular-level fMRI. Comprehensive and intuitively structured, this book engages the reader with a first-person account of the development and history of the fMRI field by the authors. The subsequent sections examine the physiological basis of fMRI, the basic principles of fMRI and its applications and the latest advances of the technology, ending with a discussion of fMRI’s future. fMRI: From Nuclear Spins to Brain Function, co-edited by leading and renowned fMRI researchers Kamil Ugurbil, Kamil Uludag and Lawrence Berliner, is an ideal resource for clinicians and researchers in the fields of neuroscience, psychology and MRI physics.
Author: Nagehan Ersoy Tunalı
Publisher: BoD – Books on Demand
ISBN: 9533079533
Category : Science
Languages : en
Pages : 570
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Book Description
Huntington's Disease is one of the well-studied neurodegenerative conditions, a quite devastating and currently incurable one. It is a brain disorder that causes certain types of neurons to become damaged, causing various parts of the brain to deteriorate and lose their function. This results in uncontrolled movements, loss of intellectual capabilities and behavioural disturbances. Since the identification of the causative mutation, there have been many significant developments in understanding the cellular and molecular perturbations. This book, "Huntington's Disease - Core Concepts and Current Advances", was prepared to serve as a source of up-to-date information on a wide range of issues involved in Huntington's Disease. It will help the clinicians, health care providers, researchers, graduate students and life science readers to increase their understanding of the clinical correlates, genetic aspects, neuropathological findings, cellular and molecular events and potential therapeutic interventions involved in HD. The book not only serves reviewed fundamental information on the disease but also presents original research in several disciplines, which collectively provide comprehensive description of the key issues in the area.
Author: Richard E. Latchaw
Publisher:
ISBN:
Category : CD-ROMs
Languages : en
Pages : 1140
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Book Description
A comprehensive account of the latest imaging techniques for both diagnosis and image-guided therapy for the many diseases of the nervous system. The book provides summary boxes and tables covering the classification of pathology, key features of the disorder, and differential diagnosis, as well as, essential color images. An accompanying CD-ROM features additional illustrations, descriptions for a particular diagnosis or therapy, and video clips of specific procedures.
