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Digital Enhancement of EEG/MEG Signals
48,80 € *
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Electroencephalography (EEG) and Magnetoencephalography (MEG) recordings are commonly used for analyzing the brain. However, in most cases, the recordings not only contain brain waves, but also artifacts of physiological (ocular, muscle, ECG artifacts) or technical (electrode popping, power-line) origins, and noise from different sources. The main aim of the work described in this thesis is the noise reduction and artifact suppression from EEG and MEG signals.Different techniques for artifact suppression have been used: A Low-Pass Filter (LPF), an instantaneous Independent Component Analysis (ICA) algorithm, a combination of ICA and LPF, a combination of ICA and State-Space Modeling (SSM), a combination of ICA and Wiener filters, and a hybrid filter (i.e., a filter that works in the time- and frequency-domains). These techniques have been tested only offline in the present work.Additionally, two artifact suppression methods that could work either offline or in real-time have been tested in real-time. The first one is a recent approach used for signal enhancement, called Empirical Mode Decomposition (EMD). This method is employed in this work for denoising, for detrending, and for suppressing the muscle artifacts from EEG signals. The second method is an algorithm here called Classification-based Signal Enhancement (CBSE). It was also used to suppress muscle artifacts in EEG signals, in real-time, using Wiener filters for signal enhancement.In order to use any artifact suppression technique, the artifacts to be removed have to be previously identified. If the artifact suppression is done offline, the detection can be carried out by visual inspection of the data by an expert, or in an automatic way. On the other hand, if the suppression of artifacts has to be done in real-time, the artifacts have to be detected automatically. A detection technique is proposed in the present work. First, different features are extracted from the independent components, and then a threshold-based classification is performed to determine which components are contaminated, what kind of artifacts they contain, and how the suppression of the artifacts is realized. This method was tested in an offline manner in this thesis.The effectiveness of the proposed artifact suppression techniques was demonstrated by application to either “semi-simulated” EEG signals artificially contaminated with artifacts, or to real EEG/MEG data from a healthy subject or a patient suffering from epilepsy (inherently contaminated with different kinds of artifacts). It is shown by visual inspection and in a quantitative manner that, after applying the different techniques, the EEG/MEG signals are enhanced.To reduce the noise, an equalizer and a Wiener filter have been used. The signals employed for this purpose correspond to those from the newly developed magnetoelectric (ME) sensors at Kiel University.

Anbieter: Dodax AT
Stand: 19.01.2020
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Digital Enhancement of EEG/MEG Signals
48,80 € *
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Digital Enhancement of EEG/MEG Signals ab 48.8 € als Taschenbuch: . Aus dem Bereich: Bücher, Wissenschaft, Technik,

Anbieter: hugendubel
Stand: 19.01.2020
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Optical Imaging of Brain Function and Metabolism 2
181,89 € *
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This volume covers the latest developments in optical imaging of the brain which is becoming an increasingly important functional neuroimaging method. Optical intrinsic signals offer unrivaled temporal and spatial resolution of functional measurements of the exposed brain cortex in animals and humans. Near-infrared spectroscopy and imaging ap proaches permit the noninvasive functional assessment of the human brain at bedside. Main advantages of these optical techniques are the biochemical specificity of the meas urements and the potential of measuring correlates of intracellular and intravascular oxy genation simultaneously. Recent data indicate that one may also measure a more direct correlate of neuronal activity associated with changes in light scattering. In this volume, recent technical progress of the optical method is covered as well as the physiological basis of the measurements. In simultaneous studies, near-infrared spec troscopy measurements are directly compared to other functional methods, especially PET and fMRI and examples are given for new applications of the NIRS-method. Based on re sults obtained with optical methods and other functional techniques the latest in our under standing of the coupling of neuronal activity and cerebral blood flow response is reviewed. This is an important basis for a better understanding of all functional neuroi maging methods which rely on neurovascular coupling such as PET, SPET and fMRI. Fi nally the optical method is put into the perspective of presently available functional neuroimaging methods including fMRI, PET, MEG and EEG.

Anbieter: Dodax
Stand: 19.01.2020
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Optical Imaging of Brain Function and Metabolism 2
186,99 € *
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This volume covers the latest developments in optical imaging of the brain which is becoming an increasingly important functional neuroimaging method. Optical intrinsic signals offer unrivaled temporal and spatial resolution of functional measurements of the exposed brain cortex in animals and humans. Near-infrared spectroscopy and imaging ap proaches permit the noninvasive functional assessment of the human brain at bedside. Main advantages of these optical techniques are the biochemical specificity of the meas urements and the potential of measuring correlates of intracellular and intravascular oxy genation simultaneously. Recent data indicate that one may also measure a more direct correlate of neuronal activity associated with changes in light scattering. In this volume, recent technical progress of the optical method is covered as well as the physiological basis of the measurements. In simultaneous studies, near-infrared spec troscopy measurements are directly compared to other functional methods, especially PET and fMRI and examples are given for new applications of the NIRS-method. Based on re sults obtained with optical methods and other functional techniques the latest in our under standing of the coupling of neuronal activity and cerebral blood flow response is reviewed. This is an important basis for a better understanding of all functional neuroi maging methods which rely on neurovascular coupling such as PET, SPET and fMRI. Fi nally the optical method is put into the perspective of presently available functional neuroimaging methods including fMRI, PET, MEG and EEG.

Anbieter: Dodax AT
Stand: 19.01.2020
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Functional Neuroimaging in Exercise and Sport S...
235,39 € *
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Regular physical exercise is associated with substantial health benefits. Recent evidence not only holds for cardiovascular effects promoting "physical health", but also for the central nervous system believed to promote "brain health". Moderate physical exercise has been found to improve learning, memory, and attentional processing, with recent research indicating that neuroprotective mechanisms and associated plasticity in brain structure and function also benefit. Physical exercise is also known to induce a range of acute or sustained psychophysiological effects, among these mood elevation, stress reduction, anxiolysis, and hypoalgesia. Today, modern functional neuroimaging techniques afford direct measurement of the acute and chronic relation of physical exercise on the human brain, as well as the correlation of the derived physiological in vivo signals with behavioral outcomes recorded during and after exercise. A wide range of imaging techniques have been applied to human exercise research, ranging from electroencephalography (EEG), magnetoencephalography (MEG), near infrared spectroscopy (NIRS), magnetic resonance imaging (MRI) to positron emission tomography (PET). All of these imaging methods provide distinct information, and they differ considerably in terms of spatial and temporal resolution, availability, cost, and associated risks. However, from a "multimodal imaging" perspective, neuroimaging provides an unprecedented potential to unravel the neurobiology of human exercise, covering a wide spectrum ranging from structural plasticity in gray and white matter, network dynamics, global and regional perfusion, evoked neuronal responses to the quantification of neurotransmitter release. The aim of this book is to provide the current state of the human neuroimaging literature in the emerging field of the neurobiological exercise sciences and to outline future applications and directions of research.

Anbieter: Dodax
Stand: 19.01.2020
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Functional Neuroimaging in Exercise and Sport S...
241,99 € *
ggf. zzgl. Versand

Regular physical exercise is associated with substantial health benefits. Recent evidence not only holds for cardiovascular effects promoting "physical health", but also for the central nervous system believed to promote "brain health". Moderate physical exercise has been found to improve learning, memory, and attentional processing, with recent research indicating that neuroprotective mechanisms and associated plasticity in brain structure and function also benefit. Physical exercise is also known to induce a range of acute or sustained psychophysiological effects, among these mood elevation, stress reduction, anxiolysis, and hypoalgesia. Today, modern functional neuroimaging techniques afford direct measurement of the acute and chronic relation of physical exercise on the human brain, as well as the correlation of the derived physiological in vivo signals with behavioral outcomes recorded during and after exercise. A wide range of imaging techniques have been applied to human exercise research, ranging from electroencephalography (EEG), magnetoencephalography (MEG), near infrared spectroscopy (NIRS), magnetic resonance imaging (MRI) to positron emission tomography (PET). All of these imaging methods provide distinct information, and they differ considerably in terms of spatial and temporal resolution, availability, cost, and associated risks. However, from a "multimodal imaging" perspective, neuroimaging provides an unprecedented potential to unravel the neurobiology of human exercise, covering a wide spectrum ranging from structural plasticity in gray and white matter, network dynamics, global and regional perfusion, evoked neuronal responses to the quantification of neurotransmitter release. The aim of this book is to provide the current state of the human neuroimaging literature in the emerging field of the neurobiological exercise sciences and to outline future applications and directions of research.

Anbieter: Dodax AT
Stand: 19.01.2020
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Analyzing Neural Time Series Data
65,99 € *
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A comprehensive guide to the conceptual, mathematical, and implementational aspects of analyzing electrical brain signals, including data from MEG, EEG, and LFP recordings.

Anbieter: buecher
Stand: 19.01.2020
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Analyzing Neural Time Series Data
65,99 € *
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A comprehensive guide to the conceptual, mathematical, and implementational aspects of analyzing electrical brain signals, including data from MEG, EEG, and LFP recordings.

Anbieter: buecher
Stand: 19.01.2020
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Digital Enhancement of EEG/MEG Signals
48,80 € *
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Digital Enhancement of EEG/MEG Signals ab 48.8 EURO

Anbieter: ebook.de
Stand: 19.01.2020
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