Intrinsic Inter-subject Variability in Functional Neuroimaging
Intrinsic Inter-subject Variability in Functional Neuroimaging

Author: Shruti Gopal Vij

Publisher:

Published: 2016

Total Pages: 256

ISBN-13:

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"The holy grail of brain imaging is the identification of a biomarker, which can identify an abnormality that can be used to diagnose disease and track the effectiveness of treatment and disease progression. Typically approaches that search for biomarkers start by identifying mean differences between groups of patients and healthy controls. However, combining data from different subjects and groups to be able to make meaningful inferences is not trivial. The structure of the brain in each individual is unique in size and shape as well as in the relative location of anatomical landmarks (e.g. sulci and gyri). When looking for mean differences in functional images, this issue is exacerbated by the presence of variability in functional localization, i.e. variability in the location of functional regions in the brain. This is notably an important reason to focus on looking for inter-individual differences or variability. Inter-subject variability in neuroimaging experiments is often viewed as noise. The analyses are setup in a manner to ignore this variability assuming that a global spatial normalization brings the data into the same space. Nonetheless, functional activation patterns can be impacted by variability in multiple ways for e.g., there could be spatial variability of the maps or variability in the spectral composition of the timecourses or variability in the connectivity between the activation patterns identified. The overarching problem this thesis seeks to contribute to, is seeking improved measures to quantify biologically significant spatial, spectral and connectivity based variability and to identify associated cognitive or behavioral differences in the distribution of brain networks. We have successfully shown that different (spatial and spectral) measures of variability in blind source separated functional activation patterns underline previously unexplained characteristics that help in discerning schizophrenia patients from healthy controls. Additionally, we show that variance measures in dynamic connectivity between networks in healthy controls can justify relationship between connectivity patterns and executive functioning abilities."--Abstract.

Quantification of Inter-subject Variability in Human Brain and Its Impact on Analysis of FMRI Data
Quantification of Inter-subject Variability in Human Brain and Its Impact on Analysis of FMRI Data

Author:

Publisher:

Published: 2004

Total Pages:

ISBN-13:

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In functional magnetic resonance imaging (fMRI) studies, inter-subject anatomical variability of the human brain has been a major challenge in finding reliable functional/anatomical correspondences. Assessment of brain-behavior relations involves a series of geometrical/statistical operations on brain images to minimize such inter-subject variability, so that group maps of brain activity relative to brain anatomy can be developed. Various methods of image registration, segmentation, and analysis have been proposed for mapping functional activity on to anatomical atlases of the brain. The two most common techniques that have been widely accepted and used by neuroimaging scientists are volume-based (VB) analysis using group registration methods and region-of-interest (ROI)-based methods using automated segmentation algorithms or macro/microanatomical probabilistic atlases for labeling. Nevertheless, the analysis results based on these techniques are significantly affected by the accuracy of the selected segmentation and/or registration methods. Furthermore, conventional fMRI data analysis techniques (VB, and ROI-based methods) mainly rely on the assumption that brain processes are common and universal among individual humans; however, besides anatomical differences, there also exist cognitive and behavioral variability among individuals due to differential engagement of brain networks even when performing an identical cognitive task. In this thesis, I have assessed the impact of anatomy-based alignment techniques (VB, and ROI-based methods) on sensitivity of fMRI data group analysis. I evaluated the effect of the type of inter-subject registration used and related factors on sensitivity of group-level fMRI data analysis. Furthermore, I have also assessed the goodness of fit of probabilistic maps by proposing an evidence-based framework for evaluation of probabilistic maps. As a test model, I have selected the human auditory cortex. Auditory cortex is an interesting ye.

Connectome
Connectome

Author: Sebastian Seung

Publisher: HMH

Published: 2012-02-07

Total Pages: 389

ISBN-13: 0547508174

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“Accessible, witty . . . an important new researcher, philosopher and popularizer of brain science . . . on par with cosmology’s Brian Greene and the late Carl Sagan” (The Plain Dealer). One of the Wall Street Journal’s 10 Best Nonfiction Books of the Year and a Publishers Weekly “Top Ten in Science” Title Every person is unique, but science has struggled to pinpoint where, precisely, that uniqueness resides. Our genome may determine our eye color and even aspects of our character. But our friendships, failures, and passions also shape who we are. The question is: How? Sebastian Seung is at the forefront of a revolution in neuroscience. He believes that our identity lies not in our genes, but in the connections between our brain cells—our particular wiring. Seung and a dedicated group of researchers are leading the effort to map these connections, neuron by neuron, synapse by synapse. It’s a monumental effort, but if they succeed, they will uncover the basis of personality, identity, intelligence, memory, and perhaps disorders such as autism and schizophrenia. Connectome is a mind-bending adventure story offering a daring scientific and technological vision for understanding what makes us who we are, as individuals and as a species. “This is complicated stuff, and it is a testament to Dr. Seung’s remarkable clarity of exposition that the reader is swept along with his enthusiasm, as he moves from the basics of neuroscience out to the farthest regions of the hypothetical, sketching out a spectacularly illustrated giant map of the universe of man.” —TheNew York Times “An elegant primer on what’s known about how the brain is organized and how it grows, wires its neurons, perceives its environment, modifies or repairs itself, and stores information. Seung is a clear, lively writer who chooses vivid examples.” —TheWashington Post

Micro-, Meso- and Macro-Connectomics of the Brain
Micro-, Meso- and Macro-Connectomics of the Brain

Author: Henry Kennedy

Publisher: Springer

Published: 2016-03-10

Total Pages: 173

ISBN-13: 3319277774

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This book has brought together leading investigators who work in the new arena of brain connectomics. This includes ‘macro-connectome’ efforts to comprehensively chart long-distance pathways and functional networks; ‘micro-connectome’ efforts to identify every neuron, axon, dendrite, synapse, and glial process within restricted brain regions; and ‘meso-connectome’ efforts to systematically map both local and long-distance connections using anatomical tracers. This book highlights cutting-edge methods that can accelerate progress in elucidating static ‘hard-wired’ circuits of the brain as well as dynamic interactions that are vital for brain function. The power of connectomic approaches in characterizing abnormal circuits in the many brain disorders that afflict humankind is considered. Experts in computational neuroscience and network theory provide perspectives needed for synthesizing across different scales in space and time. Altogether, this book provides an integrated view of the challenges and opportunities in deciphering brain circuits in health and disease.

Neuroscience in the 21st Century
Neuroscience in the 21st Century

Author: Donald W. Pfaff

Publisher: Springer

Published: 2016-10-27

Total Pages: 0

ISBN-13: 9781493934737

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Edited and authored by a wealth of international experts in neuroscience and related disciplines, this key new resource aims to offer medical students and graduate researchers around the world a comprehensive introduction and overview of modern neuroscience. Neuroscience research is certain to prove a vital element in combating mental illness in its various incarnations, a strategic battleground in the future of medicine, as the prevalence of mental disorders is becoming better understood each year. Hundreds of millions of people worldwide are affected by mental, behavioral, neurological and substance use disorders. The World Health Organization estimated in 2002 that 154 million people globally suffer from depression and 25 million people from schizophrenia; 91 million people are affected by alcohol use disorders and 15 million by drug use disorders. A more recent WHO report shows that 50 million people suffer from epilepsy and 24 million from Alzheimer’s and other dementias. Because neuroscience takes the etiology of disease—the complex interplay between biological, psychological, and sociocultural factors—as its object of inquiry, it is increasingly valuable in understanding an array of medical conditions. A recent report by the United States’ Surgeon General cites several such diseases: schizophrenia, bipolar disorder, early-onset depression, autism, attention deficit/ hyperactivity disorder, anorexia nervosa, and panic disorder, among many others. Not only is this volume a boon to those wishing to understand the future of neuroscience, it also aims to encourage the initiation of neuroscience programs in developing countries, featuring as it does an appendix full of advice on how to develop such programs. With broad coverage of both basic science and clinical issues, comprising around 150 chapters from a diversity of international authors and including complementary video components, Neuroscience in the 21st Century in its second edition serves as a comprehensive resource to students and researchers alike.

Quantification of Inter-subject Variability in Human Brain and Its Impact on Analysis of FMRI Data
Quantification of Inter-subject Variability in Human Brain and Its Impact on Analysis of FMRI Data

Author:

Publisher:

Published: 2004

Total Pages:

ISBN-13:

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In functional magnetic resonance imaging (fMRI) studies, inter-subject anatomical variability of the human brain has been a major challenge in finding reliable functional/anatomical correspondences. Assessment of brain-behavior relations involves a series of geometrical/statistical operations on brain images to minimize such inter-subject variability, so that group maps of brain activity relative to brain anatomy can be developed. Various methods of image registration, segmentation, and analysis have been proposed for mapping functional activity on to anatomical atlases of the brain. The two most common techniques that have been widely accepted and used by neuroimaging scientists are volume-based (VB) analysis using group registration methods and region-of-interest (ROI)-based methods using automated segmentation algorithms or macro/microanatomical probabilistic atlases for labeling. Nevertheless, the analysis results based on these techniques are significantly affected by the accuracy of the selected segmentation and/or registration methods. Furthermore, conventional fMRI data analysis techniques (VB, and ROI-based methods) mainly rely on the assumption that brain processes are common and universal among individual humans; however, besides anatomical differences, there also exist cognitive and behavioral variability among individuals due to differential engagement of brain networks even when performing an identical cognitive task. In this thesis, I have assessed the impact of anatomy-based alignment techniques (VB, and ROI-based methods) on sensitivity of fMRI data group analysis. I evaluated the effect of the type of inter-subject registration used and related factors on sensitivity of group-level fMRI data analysis. Furthermore, I have also assessed the goodness of fit of probabilistic maps by proposing an evidence-based framework for evaluation of probabilistic maps. As a test model, I have selected the human auditory cortex. Auditory cortex is an interesting ye.

Mental Processes in the Human Brain
Mental Processes in the Human Brain

Author: Jon Driver

Publisher: Oxford University Press (UK)

Published: 2008-02-21

Total Pages: 308

ISBN-13: 0199230617

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Advanced methods for imaging brain structure and activity are leading to sophisticated accounts of how mental processes are implemented in the brain. This title provides an overview of the advances and future challenges in understanding the neurobiological basis of mental processes that are characteristically human.

Statistical Parametric Mapping: The Analysis of Functional Brain Images
Statistical Parametric Mapping: The Analysis of Functional Brain Images

Author: William D. Penny

Publisher: Elsevier

Published: 2011-04-28

Total Pages: 689

ISBN-13: 0080466508

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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

fMRI Neurofeedback
fMRI Neurofeedback

Author: Michelle Hampson

Publisher: Academic Press

Published: 2021-10-09

Total Pages: 366

ISBN-13: 0128224363

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fMRI Neurofeedback provides a perspective on how the field of functional magnetic resonance imaging (fMRI) neurofeedback has evolved, an introduction to state-of-the-art methods used for fMRI neurofeedback, a review of published neuroscientific and clinical applications, and a discussion of relevant ethical considerations. It gives a view of the ongoing research challenges throughout and provides guidance for researchers new to the field on the practical implementation and design of fMRI neurofeedback protocols. This book is designed to be accessible to all scientists and clinicians interested in conducting fMRI neurofeedback research, addressing the variety of different knowledge gaps that readers may have given their varied backgrounds and avoiding field-specific jargon. The book, therefore, will be suitable for engineers, computer scientists, neuroscientists, psychologists, and physicians working in fMRI neurofeedback. - Provides a reference on fMRI neurofeedback covering history, methods, mechanisms, clinical applications, and basic research, as well as ethical considerations - Offers contributions from international experts—leading research groups are represented, including from Europe, Japan, Israel, and the United States - Includes coverage of data analytic methods, study design, neuroscience mechanisms, and clinical considerations - Presents a perspective on future translational development