Download or read book Electrocorticographic Representations of Semantic Information in the Human Cortex written by Nicholas Paul Szrama and published by . This book was released on 2018 with total page 224 pages. Available in PDF, EPUB and Kindle. Book excerpt: Semantics is a broad field of research that examines the literal meanings behind words, objects, concepts, and actions. Semantic memory is a critical component of our daily interactions with the world and it describes the cumulative knowledge that we acquire throughout our lifetime. Despite its importance, there is an incomplete understanding of how semantic information is organized, accessed, and retrieved in the brain. In this body of work, electrocorticographic (ECoG) potentials are recorded from five subjects while they perform a variant of the Deese, Roediger, and McDermott false memory experiment. By design, the auditory word stimuli used in this experiment were chosen to have strong semantic relationships with multiple non-presented semantic concepts. This design allowed the neural correlates to semantic information to be examined without an excessive repetition of identical word stimuli. In addition to these predefined semantic concepts, higher order semantic relationships across all sets of words were also studied using word2vec word embeddings. The DRM task was found to elicit strong high gamma ECoG power increases along the superior temporal gyrus during the auditory presentation of the stimuli. However, ECoG spectral power estimates did not distinguish individual semantic concepts or low-level semantic categories. Weak but significant correlations with semantic word embeddings particularly in the delta band were observed both in the within-electrode univariate ECoG spectral power patterns and the cross-electrode spatial ECoG power patterns. Additionally, repetition suppression patterns in ECoG power were unable to significantly discriminate different semantic concepts. Event-related potentials were also unable to distinguish individual semantic categories. In contrast to semantics, ECoG power at multiple frequencies were shown to reliably track the auditory envelope with a high correlation, statistically distinguish multiple vowels and consonants, and significantly (negatively) correlated with estimates of word imageability and word frequency. Taken together, these findings illustrate the degree of language-based information available within macroscale electrocorticographic recordings.
Download or read book Semantic Representation in the Human Brain written by Alexander Huth and published by . This book was released on 2013 with total page 127 pages. Available in PDF, EPUB and Kindle. Book excerpt: The goal of the human sensory system is to build a useful internal representation of the world. In vision, this means that the brain categorizes and identifies all the objects and actions that are being observed. In language, it means that the brain understands the meaning of each word that is being perceived, and integrates across words to understand the meaning of a narrative. Both of these processes can be seen as extracting the meaning, or semantic content, from a dense stream of sensory information. We know very little about how the brain accomplishes these feats. Indeed, entire fields of research (computer vision and natural language processing) are devoted to reproducing on a computer feats of understanding that the human brain accomplishes with ease. We may be able to gain insight into these processes by studying how the semantic information extracted from visual and linguistic stimuli is represented in the brain. This dissertation describes three functional magnetic resonance imaging (fMRI) experiments that have helped to reveal how visual and linguistic semantic information are represented across the human cerebral cortex. These experiments relied on a relatively new fMRI analysis methodology known as voxel-wise modeling (VM). Although this methodology was developed for modeling how the brain represents the structure of visual information, it was adapted here for modeling representation of the extremely complex semantic information present in natural movies and natural narrative stories. The first experiment (Chapter 2) showed that information about object and action categories present in natural movies is represented in a low-dimensional semantic space that is shared across subjects. Projecting this semantic space across the cortex revealed that semantic information is represented in broad cortical gradients that cover a surprising amount of the cortical surface. The second experiment (Chapter 3) showed that information about the semantic content of narrative spoken stories is also represented in a low-dimensional space that is shared across subjects. To model the complex cortical maps for this semantic space a new technique was developed called PrAGMATiC (Probabilistic And Generative Model of Areas Tiling the Cortex). This new technique revealed that the cortical semantic maps can be explained by about 230 functional areas that cover much of the prefrontal cortex, temporoparietal junction, precuneus, and temporal cortex. Finally, the third experiment (Chapter 4) showed that a novel hierarchical logistic regression (HLR) model could accurately decode the categories of objects and actions present in natural movies from fMRI responses.
Download or read book Brain Computer Interface Research written by Christoph Guger and published by Springer Nature. This book was released on 2024-02-01 with total page 149 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book showcases recent trends in brain-computer interface development. It highlights fascinating results in areas such as language decoding, spinal cord stimulation to enable gait and to restore hand functions. The contributions are based on the 12 nominated brain-computer interface projects of the BCI Award 2022. Every year an international jury selects the most innovate BCI projects and nominates 12 projects before selecting the 1st, 2nd and 3rd place winners. In the book, each project is described in detail by the team of scientists behind it, and the editors provide a concluding discussion of the highlights and overall progress in the field.
Download or read book Research Awards Index written by and published by . This book was released on 1989 with total page 742 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Human Auditory Cortex written by David Poeppel and published by Springer Science & Business Media. This book was released on 2012-04-12 with total page 404 pages. Available in PDF, EPUB and Kindle. Book excerpt: We live in a complex and dynamically changing acoustic environment. To this end, the auditory cortex of humans has developed the ability to process a remarkable amount of diverse acoustic information with apparent ease. In fact, a phylogenetic comparison of auditory systems reveals that human auditory association cortex in particular has undergone extensive changes relative to that of other species, although our knowledge of this remains incomplete. In contrast to other senses, human auditory cortex receives input that is highly pre-processed in a number of sub-cortical structures; this suggests that even primary auditory cortex already performs quite complex analyses. At the same time, much of the functional role of the various sub-areas in human auditory cortex is still relatively unknown, and a more sophisticated understanding is only now emerging through the use of contemporary electrophysiological and neuroimaging techniques. The integration of results across the various techniques signify a new era in our knowledge of how human auditory cortex forms basis for auditory experience. This volume on human auditory cortex will have two major parts. In Part A, the principal methodologies currently used to investigate human auditory cortex will be discussed. Each chapter will first outline how the methodology is used in auditory neuroscience, highlighting the challenges of obtaining data from human auditory cortex; second, each methods chapter will provide two or (at most) three brief examples of how it has been used to generate a major result about auditory processing. In Part B, the central questions for auditory processing in human auditory cortex are covered. Each chapter can draw on all the methods introduced in Part A but will focus on a major computational challenge the system has to solve. This volume will constitute an important contemporary reference work on human auditory cortex. Arguably, this will be the first and most focused book on this critical neurological structure. The combination of different methodological and experimental approaches as well as a diverse range of aspects of human auditory perception ensures that this volume will inspire novel insights and spurn future research.
Download or read book Cortical Representation Underlying the Semantic Processing of Numerical Symbols written by Stephan E. Vogel and published by . This book was released on 2013 with total page 392 pages. Available in PDF, EPUB and Kindle. Book excerpt: Humans possess the remarkable ability to process numerical information using numerical symbols such as Arabic digits. A growing body of neuroimaging work has provided new insights into the neural correlates associated with symbolic numerical magnitude processing. However, little is known about the cortical specialization underlying the representation of symbolic numerical magnitude in adults and children. To constrain our current knowledge, I conducted a series of functional Magnetic Resonance Imaging (fMRI) studies that aimed to better understand the functional specialization of symbolic numerical magnitudes representation in the human brain. Using a number line estimation task, the first study contrasted the brain activation associated with processing symbolic numerical magnitude against the brain activation associated with non-numerical magnitude (brightness) processing. Results demonstrated a right lateralized parietal network that was commonly engaged when magnitude dimensions were processed. However, the left intraparietal sulcus (IPS) was additionally activated when symbolic numerical magnitudes were estimated, suggesting that number is a special category amongst magnitude dimensions and that the left hemisphere plays a critical role in representing number. The second study tested a child friendly version of an fMRI-adaptation paradigm in adults. For this participant's brain response was habituated to a numerical value (i.e., 6) and signal recovery in response to the presentation of numerical deviants was investigated. Across two different brain normalization procedures results showed a replication of previous findings demonstrating that the brain response of the IPS is modulated by the semantic meaning of numbers in the absence of overt response selection. The last study aimed to unravel developmental changes in the cortical representation of symbolic numerical magnitudes in children. Using the paradigm tested in chapter 2, results demonstrated an increase in the signal recovery with age in the left IPS as well as an age-independent signal recovery in the right IPS. This finding indicates that the left IPS becomes increasingly specialized for the representation of symbolic numerical magnitudes over developmental time, while the right IPS may play a different and earlier role in symbolic numerical magnitude representation. Findings of these studies are discussed in relation to our current knowledge about symbolic numerical magnitude representation.
Download or read book Electrocorticographic Brain Computer Interfaces written by Mikhail Lebedev and published by Frontiers Media SA. This book was released on 2022-02-22 with total page 227 pages. Available in PDF, EPUB and Kindle. Book excerpt: Topic Editor Christoph Guger is the CEO of Guger Technologies. All other topic editors declare no competing interests with regards to the Research Topic subject.
Download or read book The Oxford Handbook of Neurolinguistics written by Greig I. de Zubicaray and published by Oxford University Press. This book was released on 2019-03-01 with total page 1093 pages. Available in PDF, EPUB and Kindle. Book excerpt: Neurolinguistics is a young and highly interdisciplinary field, with influences from psycholinguistics, psychology, aphasiology, and (cognitive) neuroscience, as well as other fields. Neurolinguistics, like psycholinguistics, covers aspects of language processing; but unlike psycholinguistics, it draws on data from patients with damage to language processing capacities, or the use of modern neuroimaging technologies such as fMRI, TMS, or both. The burgeoning interest in neurolinguistics reflects that an understanding of the neural bases of this data can inform more biologically plausible models of the human capacity for language. The Oxford Handbook of Neurolinguistics provides concise overviews of this rapidly-growing field, and engages a broad audience with an interest in the neurobiology of language. The chapters do not attempt to provide exhaustive coverage, but rather present discussions of prominent questions posed by given topics. The volume opens with essential methodological chapters: Section I, Methods, covers the key techniques and technologies used to study the neurobiology of language today, with chapters structured along the basic divisions of the field. Section II addresses the neurobiology of language acquisition during healthy development and in response to challenges presented by congenital and acquired conditions. Section III covers the many facets of our articulate brain, or speech-language pathology, and the capacity for language production-written, spoken, and signed. Questions regarding how the brain comprehends meaning, including emotions at word and discourse levels, are addressed in Section IV. Finally, Section V reaches into broader territory, characterizing and contextualizing the neurobiology of language with respect to more fundamental neuroanatomical mechanisms and general cognitive domains.
Download or read book Semantic Cognition written by Timothy T. Rogers and published by MIT Press. This book was released on 2004 with total page 446 pages. Available in PDF, EPUB and Kindle. Book excerpt: A mechanistic theory of the representation and use of semantic knowledge that uses distributed connectionist networks as a starting point for a psychological theory of semantic cognition.
Download or read book Neural Mechanisms of Perceptual Categorization as Precursors to Speech Perception written by Einat Liebenthal and published by Frontiers Media SA. This book was released on 2017-05-03 with total page 188 pages. Available in PDF, EPUB and Kindle. Book excerpt: Perceptual categorization is fundamental to the brain’s remarkable ability to process large amounts of sensory information and efficiently recognize objects including speech. Perceptual categorization is the neural bridge between lower-level sensory and higher-level language processing. A long line of research on the physical properties of the speech signal as determined by the anatomy and physiology of the speech production apparatus has led to descriptions of the acoustic information that is used in speech recognition (e.g., stop consonants place and manner of articulation, voice onset time, aspiration). Recent research has also considered what visual cues are relevant to visual speech recognition (i.e., the visual counter-parts used in lipreading or audiovisual speech perception). Much of the theoretical work on speech perception was done in the twentieth century without the benefit of neuroimaging technologies and models of neural representation. Recent progress in understanding the functional organization of sensory and association cortices based on advances in neuroimaging presents the possibility of achieving a comprehensive and far reaching account of perception in the service of language. At the level of cell assemblies, research in animals and humans suggests that neurons in the temporal cortex are important for encoding biological categories. On the cellular level, different classes of neurons (interneurons and pyramidal neurons) have been suggested to play differential roles in the neural computations underlying auditory and visual categorization. The moment is ripe for a research topic focused on neural mechanisms mediating the emergence of speech representations (including auditory, visual and even somatosensory based forms). Important progress can be achieved by juxtaposing within the same research topic the knowledge that currently exists, the identified lacunae, and the theories that can support future investigations. This research topic provides a snapshot and platform for discussion of current understanding of neural mechanisms underlying the formation of perceptual categories and their relationship to language from a multidisciplinary and multisensory perspective. It includes contributions (reviews, original research, methodological developments) pertaining to the neural substrates, dynamics, and mechanisms underlying perceptual categorization and their interaction with neural processes governing speech perception.
Download or read book Event Related Dynamics of Brain Oscillations written by Christa Neuper and published by Elsevier. This book was released on 2006-12-03 with total page 465 pages. Available in PDF, EPUB and Kindle. Book excerpt: Research on brain oscillations and event-related electroencephalography (EEG) and event-related (de-) synchronization (ERD/ERS) in particular became a rapidly growing field in the last decades. A large number of laboratories worldwide are using ERD/ERS to study cognitive and motor brain function and the importance of this tool in neurocognitive research is widely recognized. This book is a summary of the most current research, methods, and applications of the study of event-related dynamics of brain oscillations. Facing the rapid progress in this field, it brings together, on the one side, fundamental questions of the underlying events, which still remain to be clarified and, on the other side, some of the most significant novel findings, which point to the key topics for future research. In particular, the chapters of this volume cover the neurophysiological fundamentals and models (Section I), new methodological approaches (Section II), current ERD research related to cognitive (Section III) and sensorimotor brain function (Section IV), invasive approaches and clinical applications (Section V), and novel developments of EEG-based brain-computer interfaces and neurofeedback (Section IV).
Download or read book Biomedical Index to PHS supported Research written by and published by . This book was released on 1991 with total page 1104 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Cognitive Neuroscience of Working Memory written by Naoyuki Osaka and published by . This book was released on 2007 with total page 418 pages. Available in PDF, EPUB and Kindle. Book excerpt: It is only relatively recently that it has been possible to study the neural processes that might underlie working memory, leading to a proliferation of research in this domain. This volume brings together leading researchers from around the world to summarise current knowledge of this field.
Download or read book Integrating Computational and Neural Findings in Visual Object Perception written by Judith C. Peters and published by Frontiers Media SA. This book was released on 2016-06-29 with total page 139 pages. Available in PDF, EPUB and Kindle. Book excerpt: The articles in this Research Topic provide a state-of-the-art overview of the current progress in integrating computational and empirical research on visual object recognition. Developments in this exciting multidisciplinary field have recently gained momentum: High performance computing enabled breakthroughs in computer vision and computational neuroscience. In parallel, innovative machine learning applications have recently become available for datamining the large-scale, high resolution brain data acquired with (ultra-high field) fMRI and dense multi-unit recordings. Finally, new techniques to integrate such rich simulated and empirical datasets for direct model testing could aid the development of a comprehensive brain model. We hope that this Research Topic contributes to these encouraging advances and inspires future research avenues in computational and empirical neuroscience.
Download or read book The Terminal Experiment written by Robert J. Sawyer and published by Penguin. This book was released on 2011-08-30 with total page 295 pages. Available in PDF, EPUB and Kindle. Book excerpt: Dr. Peter Hobson has created three electronic simulations of his own personality. But they all have escaped from Hobson's computer into the web-and one of them is a killer.
Download or read book Youmans and Winn Neurological Surgery E Book written by H. Richard Winn and published by Elsevier Health Sciences. This book was released on 2022-01-21 with total page 7439 pages. Available in PDF, EPUB and Kindle. Book excerpt: Widely regarded as the definitive reference in the field, Youmans and Winn Neurological Surgery offers unparalleled, multimedia coverage of the entirety of this complex specialty. Fully updated to reflect recent advances in the basic and clinical neurosciences, the 8th Edition covers everything you need to know about functional and restorative neurosurgery, deep brain stimulation, stem cell biology, radiological and nuclear imaging, and neuro-oncology, as well as minimally invasive surgeries in spine and peripheral nerve surgery, and endoscopic and other approaches for cranial procedures and cerebrovascular diseases. In four comprehensive volumes, Dr. H. Richard Winn and his expert team of editors and authors provide updated content, a significantly expanded video library, and hundreds of new video lectures that help you master new procedures, new technologies, and essential anatomic knowledge in neurosurgery. - Discusses current topics such as diffusion tensor imaging, brain and spine robotic surgery, augmented reality as an aid in neurosurgery, AI and big data in neurosurgery, and neuroimaging in stereotactic functional neurosurgery. - 55 new chapters provide cutting-edge information on Surgical Anatomy of the Spine, Precision Medicine in Neurosurgery, The Geriatric Patient, Neuroanesthesia During Pregnancy, Laser Interstitial Thermal Therapy for Epilepsy, Fetal Surgery for Myelomeningocele, Rehabilitation of Acute Spinal Cord Injury, Surgical Considerations for Patients with Polytrauma, Endovascular Approaches to Intracranial Aneurysms, and much more. - Hundreds of all-new video lectures clarify key concepts in techniques, cases, and surgical management and evaluation. Notable lecture videos include multiple videos on Thalamotomy for Focal Hand Dystonia and a video to accompany a new chapter on the Basic Science of Brain Metastases. - An extensive video library contains stunning anatomy videos and videos demonstrating intraoperative procedures with more than 800 videos in all. - Each clinical section contains chapters on technology specific to a clinical area. - Each section contains a chapter providing an overview from experienced Section Editors, including a report on ongoing controversies within that subspecialty. - Enhanced eBook version included with purchase. Your enhanced eBook allows you to access all of the text, figures, and references from the book on a variety of devices.
Download or read book The Handbook of Psycholinguistics written by Eva M. Fernández and published by John Wiley & Sons. This book was released on 2020-10-27 with total page 784 pages. Available in PDF, EPUB and Kindle. Book excerpt: Incorporating approaches from linguistics and psychology, The Handbook of Psycholinguistics explores language processing and language acquisition from an array of perspectives and features cutting edge research from cognitive science, neuroscience, and other related fields. The Handbook provides readers with a comprehensive review of the current state of the field, with an emphasis on research trends most likely to determine the shape of psycholinguistics in the years ahead. The chapters are organized into three parts, corresponding to the major areas of psycholinguists: production, comprehension, and acquisition. The collection of chapters, written by a team of international scholars, incorporates multilingual populations and neurolinguistic dimensions. Each of the three sections also features an overview chapter in which readers are introduced to the different theoretical perspectives guiding research in the area covered in that section. Timely, comprehensive, and authoritative, The Handbook of Psycholinguistics is a valuable addition to the reference shelves of researchers in psychology, linguistics, and cognitive science, as well as advanced undergraduates and graduate students interested in how language works in the human mind and how language is acquired.
