Download or read book Analysis Methods for the Study of Multimodal MRI and Individual Variability in Brain Structure and Function written by Mohammed Patel and published by . This book was released on 2022 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: "The past two decades have seen significant advances in the field of neuroimaging. Progress in magnetic resonance imaging (MRI) and increasing availability of large scale public datasets have made it more common for researchers to study the brain via multiple measures of brain structure and function. These rich datasets are accompanied by in depth behavioural phenotyping as well, so that researchers may relate neuroanatomical measurements to cognitive function. This offers a unique and exciting opportunity, but necessitates corresponding advances in analysis methods. Traditional univariate and single modality approaches suffer from limitations in the context of current large-scale multivariate analyses. The main contribution of this thesis is the integration of multimodal MRI data into a novel analytical framework which, using non-negative matrix factorization, enables the study of inter-individual variation and its relation to behavioural data. Chapter 3 presents a novel analytical framework for parcellating brain anatomy based on multimodal MRI data. Non-negative matrix factorization (NMF) is applied to structural and diffusion MRI data of the human hippocampus in a sample of healthy young adults. This approach identifies four distinct hippocampus subregions, each displaying different anatomical properties. Additionally, we perform a multivariate brain-behaviour analysis to show that individual variation within each of the four regions demonstrates strong relationships to a wide variety of behavioural and demographic features. Chapter 4 studies the relationship between cortical anatomy and longitudinal cognitive trajectories. Here we study a unique sample of healthy elderly individuals from Whitehall II Imaging Sub Study, with structural and diffusion MRI data collected in late life and cognitive performance assessed from mid-life to late life at 5 year intervals. Applying the methods developed in Chapter 3, we identify two latent dimensions relating late life cortical anatomy and mid to late life cognitive trajectories. Each contains a mixture of maintenance and decline, suggesting a heterogenous relationship between brain and behaviour. Finally, we find that mid-life features are the dominant factor in determining late life phenotypes which adds substantial evidence towards using a full lifespan approach when studying aging. Chapter 5 studies structure-function relationships in the brain. Previous studies have shown that regions of the brain with similar structural properties are likely to share similar functional activity properties. We applied NMF to structural and functional measurements in a sample of healthy young adults to show that previous group level findings had indeed obscured individual level variability. This approach shows that in certain regions, some but not all individuals display strong structure-function coupling. This finding demonstrates how the NMF framework used in this thesis can go beyond group level findings to highlight individual variability. The techniques proposed in this thesis are adaptable to a variety of neuroimaging modalities and data types, and will thus provide advancements for future works to fully capitalize on the growth of the neuroimaging field to build towards individual level applications"--

Download or read book Probing Brain Behavior Relationship with Multimodal Imaging Methods and Clinical Applications written by Bin Jing and published by Frontiers Media SA. This book was released on 2024-04-10 with total page 197 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nowadays, exploring the brain-behavior relationship via MRI, EEG, fNIRS, and MEG has become a research hotspot further accelerated by the emergence of large-sample open-source datasets, such as UK Biobank, Human Connectome Project, the Adolescent Brain Cognitive Development, the National Institute of Mental Health (NIMH) Intramural Healthy Volunteer Dataset, the TUH EEG CORPUS, and many other multimodal datasets. Many prior studies have conducted various prediction tasks in different populations (from infants to adults; from healthy subjects to patients) with miscellaneous imaging modalities, however, to construct a precise, generalizable, and reproducible brain-behavior relationship is still facing many challenges, for example, individual variability, multi-site heterogeneity, imaging result interpretability, model generalization, low prediction performance, and lack of clinical applications

Download or read book Multimodal Imaging in Neurology written by Hans-Peter Müller and published by Morgan & Claypool Publishers. This book was released on 2008 with total page 85 pages. Available in PDF, EPUB and Kindle. Book excerpt: The field of brain imaging is developing at a rapid pace and has greatly advanced the areas of cognitive and clinical neuroscience. The availability of neuroimaging techniques, especially magnetic resonance imaging (MRI), functional MRI (fMRI), diffusion tensor imaging (DTI) and magnetoencephalography (MEG) and magnetic source imaging (MSI) has brought about breakthroughs in neuroscience. To obtain comprehensive information about the activity of the human brain, different analytical approaches should be complemented. Thus, in "intermodal multimodality" imaging, great efforts have been made to combine the highest spatial resolution (MRI, fMRI) with the best temporal resolution (MEG or EEG). "Intramodal multimodality" imaging combines various functional MRI techniques (e.g., fMRI, DTI, and/or morphometric/volumetric analysis). The multimodal approach is conceptually based on the combination of different noninvasive functional neuroimaging tools, their registration and cointegration. In particular, the combination of imaging applications that map different functional systems is useful, such as fMRI as a technique for the localization of cortical function and DTI as a technique for mapping of white matter fiber bundles or tracts. This booklet gives an insight into the wide field of multimodal imaging with respect to concepts, data acquisition, and postprocessing. Examples for intermodal and intramodal multimodality imaging are also demonstrated.

Download or read book The Statistical Analysis of Functional MRI Data written by Nicole Lazar and published by Springer Science & Business Media. This book was released on 2008-06-10 with total page 302 pages. Available in PDF, EPUB and Kindle. Book excerpt: The study of brain function is one of the most fascinating pursuits of m- ern science. Functional neuroimaging is an important component of much of the current research in cognitive, clinical, and social psychology. The exci- ment of studying the brain is recognized in both the popular press and the scienti?c community. In the pages of mainstream publications, including The New York Times and Wired, readers can learn about cutting-edge research into topics such as understanding how customers react to products and - vertisements (“If your brain has a ‘buy button,’ what pushes it?”, The New York Times,October19,2004),howviewersrespondtocampaignads(“Using M. R. I. ’s to see politics on the brain,” The New York Times, April 20, 2004; “This is your brain on Hillary: Political neuroscience hits new low,” Wired, November 12,2007),howmen and womenreactto sexualstimulation (“Brain scans arouse researchers,”Wired, April 19, 2004), distinguishing lies from the truth (“Duped,” The New Yorker, July 2, 2007; “Woman convicted of child abuse hopes fMRI can prove her innocence,” Wired, November 5, 2007), and even what separates “cool” people from “nerds” (“If you secretly like Michael Bolton, we’ll know,” Wired, October 2004). Reports on pathologies such as autism, in which neuroimaging plays a large role, are also common (for - stance, a Time magazine cover story from May 6, 2002, entitled “Inside the world of autism”).

Download or read book Handbook of Functional MRI Data Analysis written by Russell A. Poldrack and published by Cambridge University Press. This book was released on 2011-08-22 with total page 239 pages. Available in PDF, EPUB and Kindle. Book excerpt: Functional magnetic resonance imaging (fMRI) has become the most popular method for imaging brain function. Handbook of Functional MRI Data Analysis provides a comprehensive and practical introduction to the methods used for fMRI data analysis. Using minimal jargon, this book explains the concepts behind processing fMRI data, focusing on the techniques that are most commonly used in the field. This book provides background about the methods employed by common data analysis packages including FSL, SPM and AFNI. Some of the newest cutting-edge techniques, including pattern classification analysis, connectivity modeling and resting state network analysis, are also discussed. Readers of this book, whether newcomers to the field or experienced researchers, will obtain a deep and effective knowledge of how to employ fMRI analysis to ask scientific questions and become more sophisticated users of fMRI analysis software.

Download or read book Atlas of Regional Anatomy of the Brain Using MRI written by Jean C. Tamraz and published by Springer Science & Business Media. This book was released on 2006-02-08 with total page 344 pages. Available in PDF, EPUB and Kindle. Book excerpt: A unique review of the essential topographical anatomy of the brain from an MRI perspective, correlating high-quality anatomical plates with high-resolution MRI images. The book includes a historical review of brain mapping and an analysis of the essential reference planes used. It provides a detailed review of the sulcal and the gyral anatomy of the human cortex, guiding readers through an interpretation of the individual brain atlas provided by high-resolution MRI. The relationship between brain structure and function is approached in a topographical fashion with an analysis of the necessary imaging methodology and displayed anatomy. An extensive coronal atlas rounds off the book.

Download or read book Multi template Analysis of Human Perirhinal Cortex in Brain MRI written by Long Xie and published by . This book was released on 2018 with total page 298 pages. Available in PDF, EPUB and Kindle. Book excerpt: The human brain is highly variable in terms of its folding pattern and the distribution of underlining cytoarchitecture. Current leading paradigms in brain structural MRI analysis have been almost completely based on methods that use a single template to capture variability between all subjects in a population, even when the underlying assumptions of these methods are not consistent with the actual anatomy. Failure to account for the anatomical variability in the analysis degrades the ability to reliably localize and accurately quantify brain regions in individual subjects. Although characterizing anatomical variability of the brain "on a whole" is desirable, it might not be feasible given an almost infinite number of anatomical configurations. However, when focusing on specific local brain regions, regional anatomical variability can often be described by discrete anatomical variants and thus can be characterized and modeled by multi-template analysis. This dissertation focuses on the human perirhinal cortex (PRC) in brain MRI. PRC is located in the medial temporal lobe (MTL) and plays important roles in semantic memory, episodic memory and visual processing systems. In addition, pathology studies have found that the PRC is the first site in the cortex that is affected by neurofibrillary tangle (NFT) pathology, the hallmark of Alzheimer's disease (AD) that is more directly linked to neurodegeneration. Thus, accurate quantification of morphometry features of the PRC may have important utility in diagnosis and monitoring of early AD, as well as brain-behavior studies in the MTL. Probably due to its large anatomical variability, PRC is surprisingly overlooked by the biomedical image analysis literature. What makes PRC an ideal structure for multi-template analysis is that 97% of its anatomical variability can be accounted by three discrete anatomical variants, defined by the depth and the branching pattern of the anterior portion of the collateral sulcus (CS) adjacent to the PRC.In this dissertation, I introduced a novel multi-template analysis pipeline for the PRC in structural brain MRI. Anatomical variants of the PRC are identified automatically from structural MRI scans. Then, we explicitly construct a template and model anatomical variability for each anatomical variant. Experimental results show that the proposed technique is able to generate templates that recover the dominant discrete variants of the PRC and establish more meaningful correspondences between subjects than a single-template approach. In the application of discriminating AD patients from cognitively normal adults, the proposed pipeline generates measurements that are more sensitive to disease status and yields results that are consistent with the patterns of NFT pathology distribution.In addition, since the cortex is organized like a sheet, it is likely that the location of the earliest NFT pathology within the PRC is itself variable across different anatomical subtypes. By applying the proposed multi-template analysis pipeline to a large dataset with subjects at different stages of the AD spectrum, we find, for the first time, discrete patterns of spatial distribution of cortical thinning between anatomical variants. Incorporating this variability in future studies will likely further improve the sensitivity of MRI-derived measures of the PRC to early detection and monitoring of AD.

Download or read book Investigating the human brainstem with structural and functional MRI written by Florian Beissner and published by Frontiers E-books. This book was released on 2014-07-30 with total page 93 pages. Available in PDF, EPUB and Kindle. Book excerpt: The brainstem is one of the least understood parts of the human brain despite its prime importance for the maintenance of basic vital functions. Owing to its role as a relay station between spinal cord, cerebellum and neocortex, the brainstem contains vital nodes of all functional systems in the central nervous system, including the visual, auditory, gustatory, vestibular, somatic and visceral senses, and the somatomotor as well as autonomic nervous systems. While the brainstem has been extensively studied in animals using invasive methods, human studies remain scarce. Magnetic resonance imaging (MRI) as a non-invasive and widely available method is one possibility to access the brainstem in humans and measure its structure as well as function. The close vicinity of the brainstem to large arteries and ventricles and the small size of the anatomical structures, however, place high demands on imaging as well as data analysis methods. Nevertheless, the field of brainstem-(f)MRI has significantly advanced in the past few years, largely due to the development of several new tools that facilitate studying this critical part of the human brain. Within this scope, the goal of this Research Topic is to compile work representing the state of the art in functional and structural MRI of the human brainstem.

Download or read book Magnetoencephalography written by Selma Supek and published by Springer. This book was released on 2014-08-07 with total page 999 pages. Available in PDF, EPUB and Kindle. Book excerpt: Magnetoencephalography (MEG) is an invaluable functional brain imaging technique that provides direct, real-time monitoring of neuronal activity necessary for gaining insight into dynamic cortical networks. Our intentions with this book are to cover the richness and transdisciplinary nature of the MEG field, make it more accessible to newcomers and experienced researchers and to stimulate growth in the MEG area. The book presents a comprehensive overview of MEG basics and the latest developments in methodological, empirical and clinical research, directed toward master and doctoral students, as well as researchers. There are three levels of contributions: 1) tutorials on instrumentation, measurements, modeling, and experimental design; 2) topical reviews providing extensive coverage of relevant research topics; and 3) short contributions on open, challenging issues, future developments and novel applications. The topics range from neuromagnetic measurements, signal processing and source localization techniques to dynamic functional networks underlying perception and cognition in both health and disease. Topical reviews cover, among others: development on SQUID-based and novel sensors, multi-modal integration (low field MRI and MEG; EEG and fMRI), Bayesian approaches to multi-modal integration, direct neuronal imaging, novel noise reduction methods, source-space functional analysis, decoding of brain states, dynamic brain connectivity, sensory-motor integration, MEG studies on perception and cognition, thalamocortical oscillations, fetal and neonatal MEG, pediatric MEG studies, cognitive development, clinical applications of MEG in epilepsy, pre-surgical mapping, stroke, schizophrenia, stuttering, traumatic brain injury, post-traumatic stress disorder, depression, autism, aging and neurodegeneration, MEG applications in cognitive neuropharmacology and an overview of the major open-source analysis tools.

Download or read book Example based Segmentation and Atlas Construction for the Analysis of Newborn Brain MRI written by Neil I. Weisenfeld and published by . This book was released on 2010 with total page 226 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: Magnetic Resonance Imaging (MRI) provides a non-invasive technique for studying brain structure and function. For the fragile newborn infant, it provides a low-risk means for collecting information about possible injury to the developing brain. In order to analyze this data quantitatively, structures or tissues of interest within the MRI image must first be identified. While this can be achieved through time-consuming, interactive hand-drawing, this method is subject to individual bias, and leads to intra- and inter-rater variability. This dissertation presents novel algorithms for segmentation and atlas construction, which together form a unique method for fully-automated labeling of cortical and subcortical gray matter, myelinated and unmyelinated white matter, and cerebrospinal fluid in Mill images of newborn brain. The key contributions of the segmentation algorithm are a novel method for training a supervised classifier from example images and a new machine learning technique based on classifier fusion and stochastic editing of training data. The atlas construction algorithm introduces a data-driven notion of group typical anatomy and a new solution, based on the Expectation-Maximization algorithm, which provides both an estimate of the group typical anatomy and transforms relating each subject to the group. This new technique is naturally resistant to outliers, converges to a stable result with fewer samples from a population than previous methods, and provides a label-specific measure of match useful for determining how well subjects match a group under a given transform model. Together these methods form the first fully-automatic newborn segmentation algorithm capable of distinguishing myelinated from unmyelinated white matter and cortical from sub-cortical gray matter. This new method makes possible reproducible, large scale studies of newborn brain with MRI and has generated preliminary results in a study of methadone exposure in utero, as well as a study of preterm infants receiving a novel intervention for complications of prematurity.

Download or read book Micro Meso and Macro Connectomics of the Brain written by Henry Kennedy and published by Springer. This book was released on 2016-03-10 with total page 173 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.

Download or read book Multimodal MRI Analysis of Structural and Functional Networks in the Human Brain written by Giovanni Battistella and published by . This book was released on 2013 with total page 105 pages. Available in PDF, EPUB and Kindle. Book excerpt: Thèse. Biologie. Médecine. 2013

Download or read book Quantification of Inter subject Variability in Human Brain and Its Impact on Analysis of FMRI Data written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.

Download or read book Multimodality MRI based Brain Network Analysis written by Jesse Aaron Brown and published by . This book was released on 2013 with total page 143 pages. Available in PDF, EPUB and Kindle. Book excerpt: Whole-brain structural and functional connectivity networks can be assessed using diffusion-weighted MRI (DW-MRI) and functional MRI (fMRI), respectively. When the brain is parcellated into its constituent subregions, specific methods quantify the relative connectivity strengths between pairs of regions. The calculation of connectivity between all pairs of regions produces a connectivity matrix. With such a matrix, mathematical methods from graph theory characterize the network for global properties of integration, segregation, and robustness. At the regional level, these methods quantify specific properties such as connection density, convergence, and isolation. In this work, we apply these methods to understand how the possession of the Apolipoprotein E e4 allele, the primary genetic risk factor for late-onset Alzheimer's Disease (AD), contributes to global and local alterations of structural and functional connectivity. In Chapter 2, we find that DW-MRI-based fiber tractography networks in aging APOE-4 carriers exhibit accelerated negative correlations between age and clustering coefficient, a measure of local axonal connection density. This trend occurs simultaneously with reductions in global cortical thickness and decrease performance on episodic memory tests. In a highly similar population, we examined fMRI-based functional connectivity networks during performance on an episodic memory task (Chapter 3). APOE-4 carriers demonstrated reduced activation during memory encoding in the entorhinal cortex, a locus of early disease change in Alzheimer's disease. The degree of activation in this region correlated with the amount of functional brain integration, suggesting a global basis for local alterations in neuronal activity. In Chapter 4, we assessed hippocampal functional and structural connectivity during episodic memory consolidation in healthy young adults. Results indicate that elevated functional connectivity in a hippocampal-cortical network was important for the process of consolidation. The structural connections of this network all traversed the parahippocamal gyrus, an area of known structural atrophy in individuals at genetic risk for AD. In Chapter 5 we describe a web-based tool for the public sharing and analysis of brain connectivity matrices, and then apply it to reveal substantial differences in the topology of whole brain structural and functional networks. Finally, Chapter 6 contains a model of cortico-hippocampal connectivity that unifies the findings from these studies.

Download or read book Encyclopedia of Computational Neuroscience written by Dieter Jaeger and published by . This book was released on with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Atlas of Regional Anatomy of the Brain Using MRI written by JEAN TAMRAZ and published by Springer. This book was released on 2009-09-02 with total page 330 pages. Available in PDF, EPUB and Kindle. Book excerpt: A unique review of the essential topographical anatomy of the brain from an MRI perspective, correlating high-quality anatomical plates with high-resolution MRI images. The book includes a historical review of brain mapping and an analysis of the essential reference planes used. It provides a detailed review of the sulcal and the gyral anatomy of the human cortex, guiding readers through an interpretation of the individual brain atlas provided by high-resolution MRI. The relationship between brain structure and function is approached in a topographical fashion with an analysis of the necessary imaging methodology and displayed anatomy. An extensive coronal atlas rounds off the book.

Download or read book Comparing Image Processing Pipelines for Brain MRI Data and Examining Default Mode and Executive Control Network White Matter Correlates of Executive Function in Multiple Sclerosis written by Salina Pirzada and published by . This book was released on 2020 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Background: Multiple sclerosis is a neurodegenerative disease characterized by demyelinated lesions and axonal loss in white matter regions of the brain. Spatially normalizing brain MRI data is performed to better facilitate comparisons between individuals or groups. MS-related brain pathologies however, can compromise spatial normalization methods. This study therefore compared five normalization methods. This study then used that identified method to investigate relationships between executive function and microstructure throughout the default mode network and executive control network white matter. Methods: Using 20 MS participants and 1 healthy control, we lesion-filled each participant's T1-weighted brain image to the Montreal Neurological Institute template using 5 normalization approaches (total: 400 normalizations). Inter-subject variability was quantified using mutual information and coefficient of variation and normalization lesion volumes were evaluated using paired sample t-tests. Using SPMCAT12 we used diffusion tensor imaging metrics, FA and MD maps from 103 participants to extract values from DMN and ECN regions via the UManitoba-Functionally-Defined Human White Matter Atlases. Executive function was assessed using the Delis-Kaplan Executive Function System Color-Word Interference Test. One-tailed Spearman correlations assessed relations between DMN and ECN white matter microstructure and individual differences in executive function. Results: SPM CAT12 with lesion filling is the most robust method for spatially normalizing MS brain imaging data. Lowest average Coefficient of Variation maps were SPM: 9.6 and 21.4 was highest for FSL. This study then found executive function scores to be significantly correlated with individual differences in white matter MD measurements from both the DMN (rho = 0.194; 96% CI = 0.0031 to 0.0347; p = 0.027) and the ECN (rho= 0.192; 95% = 0.029 to 0.345; p= 0.029), but not from global white matter (rho = 0.106; 95% CI = -0.059 to 0.0266; p = 0.147). Conclusion: This thesis: 1) compared spatial normalization methods on brain MRI data in the presence of MS lesions and identified an optimal approach for comparing quantitative structural imaging metrics, and 2) used this robust method to investigate relationships between EF and microstructure throughout the DMN and ECN WM. These findings have expanded our understanding of best-practices in MRI data analysis and cognitive functioning in MS.